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Sample records for community atmosphere model

  1. Performance Engineering in the Community Atmosphere Model

    SciTech Connect

    Worley, P; Mirin, A; Drake, J; Sawyer, W

    2006-05-30

    The Community Atmosphere Model (CAM) is the atmospheric component of the Community Climate System Model (CCSM) and is the primary consumer of computer resources in typical CCSM simulations. Performance engineering has been an important aspect of CAM development throughout its existence. This paper briefly summarizes these efforts and their impacts over the past five years.

  2. A Community Atmosphere Model with Superparameterized Clouds

    SciTech Connect

    Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim

    2013-06-18

    In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.

  3. The Whole Atmosphere Community Climate Model

    NASA Astrophysics Data System (ADS)

    Boville, B. A.; Garcia, R. R.; Sassi, F.; Kinnison, D.; Roble, R. G.

    The Whole Atmosphere Community Climate Model (WACCM) is an upward exten- sion of the National Center for Atmospheric Research Community Climate System Model. WACCM simulates the atmosphere from the surface to the lower thermosphere (140 km) and includes both dynamical and chemical components. The salient points of the model formulation will be summarized and several aspects of its performance will be discussed. Comparison with observations indicates that WACCM produces re- alistic temperature and zonal wind distributions. Both the mean state and interannual variability will be summarized. Temperature inversions in the midlatitude mesosphere have been reported by several authors and are also found in WACCM. These inver- sions are formed primarily by planetary wave forcing, but the background state on which they form also requires gravity wave forcing. The response to sea surface temperature (SST) anomalies will be examined by com- paring simulations with observed SSTs for 1950-1998 to a simulation with clima- tological annual cycle of SSTs. The response to ENSO events is found to extend though the winter stratosphere and mesosphere and a signal is also found at the sum- mer mesopause. The experimental framework allows the ENSO signal to be isolated, because no other forcings are included (e.g. solar variability and volcanic eruptions) which complicate the observational record. The temperature and wind variations asso- ciated with ENSO are large enough to generate significant perturbations in the chem- ical composition of the middle atmosphere, which will also be discussed.

  4. Ensemble data assimilation in the Whole Atmosphere Community Climate Model

    NASA Astrophysics Data System (ADS)

    Pedatella, N. M.; Raeder, K.; Anderson, J. L.; Liu, H.-L.

    2014-08-01

    We present results pertaining to the assimilation of real lower, middle, and upper atmosphere observations in the Whole Atmosphere Community Climate Model (WACCM) using the Data Assimilation Research Testbed (DART) ensemble adjustment Kalman filter. The ability to assimilate lower atmosphere observations of aircraft and radiosonde temperature and winds, satellite drift winds, and Constellation Observing System for Meteorology, Ionosphere, and Climate refractivity along with middle/upper atmosphere temperature observations from SABER and Aura MLS is demonstrated. The WACCM+DART data assimilation system is shown to be able to reproduce the salient features, and variability, of the troposphere present in the National Centers for Environmental Prediction/National Center for Atmospheric Research Re-Analysis. In the mesosphere, the fit of WACCM+DART to observations is found to be slightly worse when only lower atmosphere observations are assimilated compared to a control experiment that is reflective of the model climatological variability. This differs from previous results which found that assimilation of lower atmosphere observations improves the fit to mesospheric observations. This discrepancy is attributed to the fact that due to the gravity wave drag parameterizations, the model climatology differs significantly from the observations in the mesosphere, and this is not corrected by the assimilation of lower atmosphere observations. The fit of WACCM+DART to mesospheric observations is, however, significantly improved compared to the control experiment when middle/upper atmosphere observations are assimilated. We find that assimilating SABER observations reduces the root-mean-square error and bias of WACCM+DART relative to the independent Aura MLS observations by ˜50%, demonstrating that assimilation of middle/upper atmosphere observations is essential for accurate specification of the mesosphere and lower thermosphere region in WACCM+DART. Last, we demonstrate that

  5. CMIP5 Simulations with the Community Earth System Model - Whole Atmosphere Community Climate Model

    NASA Astrophysics Data System (ADS)

    Mills, M. J.; Marsh, D. R.; CalvoFernandez, N.; Kinnison, D. E.; Lamarque, J.

    2011-12-01

    We have used the Whole Atmosphere Community Climate Model (WACCM) to simulate the Earth's climate from pre-industrial conditions to the end of the 21st Century in several experiments following the Coupled Model Intercomparison Project Phase 5 (CMIP5) protocols. We present preliminary analysis of these coupled experiments, highlighting the effects of chemistry and physics above the troposphere on climate. WACCM was developed to understand the couplings between atmospheric layers, the role of chemical and physical processes in defining these couplings, and the interaction between the Earth's atmosphere and the Sun. The current version of WACCM spans the range of altitude from the Earth's surface to the lower thermosphere (~140 km) and is based on version 1 of the Community Earth System Model (CESM-1). WACCM has been used to predict the evolution of ozone and other radiatively active species in the middle and upper atmosphere; to study effects of the stratosphere on tropospheric climate, including the response to increased greenhouse gases; and for independent investigations. We compare climate trends in CMIP5 experiments from WACCM to those in the low-top version of CESM. We examine the coupling between the upper and lower atmosphere, including the quasi-biennial oscillation, sudden stratospheric warmings, the solar cycle, and surface climate.

  6. Subcycled dynamics in the Spectral Community Atmosphere Model, version 4

    SciTech Connect

    Taylor, Mark; Evans, Katherine J; Hack, James J; Worley, Patrick H

    2010-01-01

    To gain computational efficiency, a split explicit time integration scheme has been implemented in the CAM spectral Eulerian dynamical core. In this scheme, already present in other dynamical core options within the Community Atmosphere Model, version 4 (CAM), the fluid dynamics portion of the model is subcycled to allow a longer time step for the parameterization schemes. The physics parameterization of CAM is not subject to the stability restrictions of the fluid dynamics, and thus finer spatial resolutions of the model do not require the physics time step to be reduced. A brief outline of the subcycling algorithm implementation and resulting model efficiency improvement is presented. A discussion regarding the effect of the climate statistics derived from short model runs is provided.

  7. Reference aquaplanet climate in the Community Atmosphere Model, Version 5

    NASA Astrophysics Data System (ADS)

    Medeiros, Brian; Williamson, David L.; Olson, Jerry G.

    2016-03-01

    Fundamental characteristics of the aquaplanet climate simulated by the Community Atmosphere Model, Version 5.3 (CAM5.3) are presented. The assumptions and simplifications of the configuration are described. A 16 year long, perpetual equinox integration with prescribed SST using the model's standard 1° grid spacing is presented as a reference simulation. Statistical analysis is presented that shows similar aquaplanet configurations can be run for about 2 years to obtain robust climatological structures, including global and zonal means, eddy statistics, and precipitation distributions. Such a simulation can be compared to the reference simulation to discern differences in the climate, including an assessment of confidence in the differences. To aid such comparisons, the reference simulation has been made available via earthsystemgrid.org. Examples are shown comparing the reference simulation with simulations from the CAM5 series that make different microphysical assumptions and use a different dynamical core.

  8. Reference aquaplanet climate in the Community Atmosphere Model, Version 5

    SciTech Connect

    Medeiros, Brian; Williamson, David L.; Olson, Jerry G.

    2016-03-18

    In this study, fundamental characteristics of the aquaplanet climate simulated by the Community Atmosphere Model, Version 5.3 (CAM5.3) are presented. The assumptions and simplifications of the configuration are described. A 16 year long, perpetual equinox integration with prescribed SST using the model’s standard 18 grid spacing is presented as a reference simulation. Statistical analysis is presented that shows similar aquaplanet configurations can be run for about 2 years to obtain robust climatological structures, including global and zonal means, eddy statistics, and precipitation distributions. Such a simulation can be compared to the reference simulation to discern differences in the climate, including an assessment of confidence in the differences. To aid such comparisons, the reference simulation has been made available via earthsystemgrid.org. Examples are shown comparing the reference simulation with simulations from the CAM5 series that make different microphysical assumptions and use a different dynamical core.

  9. Reference aquaplanet climate in the Community Atmosphere Model, Version 5

    DOE PAGES

    Medeiros, Brian; Williamson, David L.; Olson, Jerry G.

    2016-03-18

    In this study, fundamental characteristics of the aquaplanet climate simulated by the Community Atmosphere Model, Version 5.3 (CAM5.3) are presented. The assumptions and simplifications of the configuration are described. A 16 year long, perpetual equinox integration with prescribed SST using the model’s standard 18 grid spacing is presented as a reference simulation. Statistical analysis is presented that shows similar aquaplanet configurations can be run for about 2 years to obtain robust climatological structures, including global and zonal means, eddy statistics, and precipitation distributions. Such a simulation can be compared to the reference simulation to discern differences in the climate, includingmore » an assessment of confidence in the differences. To aid such comparisons, the reference simulation has been made available via earthsystemgrid.org. Examples are shown comparing the reference simulation with simulations from the CAM5 series that make different microphysical assumptions and use a different dynamical core.« less

  10. The spectral element dynamical core in the Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Taylor, Mark

    2013-11-01

    I will describe our work developing CAM-SE, a highly scalable version of the Community Atmosphere Model (CAM). CAM-SE solves the hydrostatic equations with a spectral element horizontal descritization and the hybrid coordinate Simmons & Burridge (1981) vertical discretization. It uses a mimetic formulation of spectral elements which preserves the adjoint and annihilator properties of the divergence, gradient and curl operations. These mimetic properties result in local conservation (to machine precision) of mass, tracer mass and (2D) potential vorticity, and semi-discrete conservation (exact with exact time-discretization) of total energy. Hyper-viscsoity is used for all numerical dissipation. The spectral element method naturally supports unstructured/variable resolution grids. We are using this capability to perform simulations with 1/8 degree resolution over the central U.S., transitioning to 1 degree over most of the globe. This is a numerically efficient way to study the resolution sensitivity of CAM's many subgrid parameterizations.

  11. Energy considerations in the Community Atmosphere Model (CAM)

    DOE PAGES

    Williamson, David L.; Olson, Jerry G.; Hannay, Cécile; ...

    2015-06-30

    An error in the energy formulation in the Community Atmosphere Model (CAM) is identified and corrected. Ten year AMIP simulations are compared using the correct and incorrect energy formulations. Statistics of selected primary variables all indicate physically insignificant differences between the simulations, comparable to differences with simulations initialized with rounding sized perturbations. The two simulations are so similar mainly because of an inconsistency in the application of the incorrect energy formulation in the original CAM. CAM used the erroneous energy form to determine the states passed between the parameterizations, but used a form related to the correct formulation for themore » state passed from the parameterizations to the dynamical core. If the incorrect form is also used to determine the state passed to the dynamical core the simulations are significantly different. In addition, CAM uses the incorrect form for the global energy fixer, but that seems to be less important. The difference of the magnitude of the fixers using the correct and incorrect energy definitions is very small.« less

  12. Energy considerations in the Community Atmosphere Model (CAM)

    SciTech Connect

    Williamson, David L.; Olson, Jerry G.; Hannay, Cécile; Toniazzo, Thomas; Yudin, Valery; Taylor, Mark

    2015-06-30

    An error in the energy formulation in the Community Atmosphere Model (CAM) is identified and corrected. Ten year AMIP simulations are compared using the correct and incorrect energy formulations. Statistics of selected primary variables all indicate physically insignificant differences between the simulations, comparable to differences with simulations initialized with rounding sized perturbations. The two simulations are so similar mainly because of an inconsistency in the application of the incorrect energy formulation in the original CAM. CAM used the erroneous energy form to determine the states passed between the parameterizations, but used a form related to the correct formulation for the state passed from the parameterizations to the dynamical core. If the incorrect form is also used to determine the state passed to the dynamical core the simulations are significantly different. In addition, CAM uses the incorrect form for the global energy fixer, but that seems to be less important. The difference of the magnitude of the fixers using the correct and incorrect energy definitions is very small.

  13. Collaborative Project. A Flexible Atmospheric Modeling Framework for the Community Earth System Model (CESM)

    SciTech Connect

    Gettelman, Andrew

    2015-10-01

    In this project we have been upgrading the Multiscale Modeling Framework (MMF) in the Community Atmosphere Model (CAM), also known as Super-Parameterized CAM (SP-CAM). This has included a major effort to update the coding standards and interface with CAM so that it can be placed on the main development trunk. It has also included development of a new software structure for CAM to be able to handle sub-grid column information. These efforts have formed the major thrust of the work.

  14. Weakening of atmospheric information flow in a warming climate in the Community Climate System Model

    NASA Astrophysics Data System (ADS)

    Deng, Yi; Ebert-Uphoff, Imme

    2014-01-01

    We introduce a new perspective of climate change by revealing the changing characteristics of atmospheric information flow in a warming climate. The key idea is to interpret large-scale atmospheric dynamical processes as information flow around the globe and to identify the pathways of this information flow using a climate network based on causal discovery and graphical models. We construct such networks using the daily geopotential height data from the Community Climate System Model Version 4.0 (CCSM4.0)'s 20th century climate simulation and 21st century climate projection. We show that in the CCSM4.0 model under enhanced greenhouse gases (GHGs) forcing, prominent midlatitude information pathways in the midtroposphere weaken and shift poleward, while major tropical information pathways start diminishing. Averaged over the entire Northern Hemisphere, the atmospheric information flow weakens. The implications of this weakening for the interconnectivity among different geographical locations and for the intrinsic predictability of the atmosphere are discussed.

  15. Global Radiative-Convective Equilibrium in the Community Atmosphere Model: Understanding Model Sensitivities

    NASA Astrophysics Data System (ADS)

    Reed, K. A.; Medeiros, B.; Bacmeister, J. T.; Lauritzen, P. H.

    2014-12-01

    In our continued effort to understand the climate system and improve its representation in general circulation models (GCMs) it is crucial to develop new methods to evaluate these models. This is certainly true as the GCM community advances towards high horizontal resolutions (i.e., grid spacing less than 0.5 degrees), which will require interpreting and improving the performance of many model components. Of specific interest is the role of convective parameterizations at these spatial scales and its impact on tropical dynamics and precipitation processes. Idealized, or reduced complexity, frameworks can be used to investigate how model assumptions impact behavior across scales. A simplified global radiative-convective equilibrium (RCE) configuration is proposed to explore the implication of horizontal resolution on equilibrium climate. RCE is the statistical equilibrium in which the radiative cooling of the atmosphere is balanced by heating due to convection and has had a fundamental place in our understanding of the Earth system. In this work, the National Center for Atmospheric Research's Community Atmosphere Model 5 (CAM5) is configured in RCE to better understand tropical climate and extremes. The RCE setup consists of an ocean-covered earth with diurnally varying, spatially uniform insolation and no rotation effects. CAM5 is run with the spectral element dynamics package at two horizontal resolutions: a standard resolution of approximately 1 degree grid spacing and a high-resolution of approximately 0.25 degree grid spacing. Surface temperature effects are considered by comparing simulations using fixed, uniform sea surface temperature to simulations using an interactive slab ocean model. The various CAM5 configurations provide useful insights into the simulation of tropical climate at the high-resolution, as well as the model's ability to simulate extreme precipitation events. In particular, the manner in which convection organizes is shown to be dependent

  16. Integrating Cloud Processes in the Community Atmosphere Model, Version 5.

    SciTech Connect

    Park, S.; Bretherton, Christopher S.; Rasch, Philip J.

    2014-09-15

    This paper provides a description on the parameterizations of global cloud system in CAM5. Compared to the previous versions, CAM5 cloud parameterization has the following unique characteristics: (1) a transparent cloud macrophysical structure that has horizontally non-overlapped deep cumulus, shallow cumulus and stratus in each grid layer, each of which has own cloud fraction, mass and number concentrations of cloud liquid droplets and ice crystals, (2) stratus-radiation-turbulence interaction that allows CAM5 to simulate marine stratocumulus solely from grid-mean RH without relying on the stability-based empirical empty stratus, (3) prognostic treatment of the number concentrations of stratus liquid droplets and ice crystals with activated aerosols and detrained in-cumulus condensates as the main sources and evaporation-sedimentation-precipitation of stratus condensate as the main sinks, and (4) radiatively active cumulus. By imposing consistency between diagnosed stratus fraction and prognosed stratus condensate, CAM5 is free from empty or highly-dense stratus at the end of stratus macrophysics. CAM5 also prognoses mass and number concentrations of various aerosol species. Thanks to the aerosol activation and the parameterizations of the radiation and stratiform precipitation production as a function of the droplet size, CAM5 simulates various aerosol indirect effects associated with stratus as well as direct effects, i.e., aerosol controls both the radiative and hydrological budgets. Detailed analysis of various simulations revealed that CAM5 is much better than CAM3/4 in the global performance as well as the physical formulation. However, several problems were also identifed, which can be attributed to inappropriate regional tuning, inconsistency between various physics parameterizations, and incomplete model physics. Continuous efforts are going on to further improve CAM5.

  17. The effects of atmospheric chemistry on radiation budget in the Community Earth Systems Model

    NASA Astrophysics Data System (ADS)

    Choi, Y.; Czader, B.; Diao, L.; Rodriguez, J.; Jeong, G.

    2013-12-01

    The Community Earth Systems Model (CESM)-Whole Atmosphere Community Climate Model (WACCM) simulations were performed to study the impact of atmospheric chemistry on the radiation budget over the surface within a weather prediction time scale. The secondary goal is to get a simplified and optimized chemistry module for the short time period. Three different chemistry modules were utilized to represent tropospheric and stratospheric chemistry, which differ in how their reactions and species are represented: (1) simplified tropospheric and stratospheric chemistry (approximately 30 species), (2) simplified tropospheric chemistry and comprehensive stratospheric chemistry from the Model of Ozone and Related Chemical Tracers, version 3 (MOZART-3, approximately 60 species), and (3) comprehensive tropospheric and stratospheric chemistry (MOZART-4, approximately 120 species). Our results indicate the different details in chemistry treatment from these model components affect the surface temperature and impact the radiation budget.

  18. Polar ozone depletion and trends as represented by the Whole Atmospheric Community Climate Model (WACCM)

    NASA Astrophysics Data System (ADS)

    Kinnison, Douglas; Solomon, Susan; Ivy, Diane; Mills, Michael; Neely, Ryan, III; Schmidt, Anja; Garcia, Rolando; Smith, Anne

    2016-04-01

    The Whole Atmosphere Community Climate Model, Version 4 (WACCM4) is a comprehensive numerical model, spanning the range of altitude from the Earth's surface to the lower thermosphere [Garcia et al., JGR, 2007; Kinnison et al., JGR, 2007; Marsh et al., J. of Climate, 2013]. WACCM4 is based on the framework of the NCAR Community Atmosphere Model, version 4 (CAM4), and includes all of the physical parameterizations of CAM4 and a finite volume dynamical core for the tracer advection. This version has a detailed representation of tropospheric and middle atmosphere chemical and physical processes. Simulations completed for the SPARC Chemistry Climate Model Initiative (CCMI), REFC1, REFC2, SENSC2, and REFC1SD scenarios are examined (see Eyring et al., SPARC Newsletter, 2013). Recent improvements in model representation of orographic gravity wave processes strongly impact temperature and therefore polar ozone depletion as well as its subsequent recovery. Model representation of volcanic events will also be shown to be important for ozone loss. Evaluation of polar ozone depletion processes (e.g., dehydration, denitrification, chemical activation) with key observations will be performed and the impact on future ozone recovery will be identified.

  19. Evaluating carbon dioxide variability in the Community Earth System Model against atmospheric observations

    NASA Astrophysics Data System (ADS)

    Keppel-Aleks, G.; Randerson, J. T.; Lindsay, K. T.; Stephens, B. B.; Moore, J. K.; Doney, S. C.; Thornton, P. E.; Mahowald, N. M.; Hoffman, F. M.; Sweeney, C.; Tans, P. P.; Wennberg, P. O.; Wofsy, S. C.

    2012-12-01

    Changes in atmospheric CO_2 variability during the 21st century may provide insight on ecosystem responses to climate change and have implications for the design of carbon monitoring programs. We analyzed results from a fully coupled climate-carbon simulation using the Community Earth System Model (CESM1-BGC). We evaluated CO2 simulated for the historical period against surface, aircraft, and column observations. The mean annual cycle in total column atmospheric CO2 was underestimated throughout the northern hemisphere relative to TCCON observations, suggesting that the growing season net flux in the land component of CESM was too weak by 50%. Sampling CESM along HIPPO transects confirmed low growing season uptake, but also showed that spring drawdown in the Northern Hemisphere began too early. The vertical gradients in CESM generally agreed with HIPPO data and with NOAA aircraft profiles outside the growing season, but were too weak during the summer. The seasonal bias suggests that vertical transport in CAM4 (the atmospheric component of CESM) was too weak year round. Model evaluation and improvement based on atmospheric observations is crucial. The simulation of surface exchange and atmospheric transport of CO2 in coupled models such as CESM may help with the design of optimal detection strategies. For example, in the simulations of the 21st century, CESM predicted increases in the mean annual cycle of atmospheric CO2 and larger horizontal gradients. Both north-south and east-west contrasts in CO2 strengthened due to changing patterns in fossil fuel emissions and terrestrial carbon exchange, and northern hemisphere interannual variability increased as well. Our results suggest that using atmospheric observations to gain insight about changing terrestrial and ocean processes over the next several decades may become more challenging as anthropogenic contributions to variability on multiple temporal and spatial scales continue to grow.

  20. CAM-chem: description and evaluation of interactive atmospheric chemistry in the Community Earth System Model

    SciTech Connect

    Lamarque, J.-F.; Emmons, L.; Hess, Peter; Kinnison, Douglas E.; Tilmes, S.; Vitt, Francis; Heald, C. L.; Holland, Elisabeth A.; Lauritzen, P. H.; Neu, J.; Orlando, J. J.; Rasch, Philip J.; Tyndall, G. S.

    2012-03-27

    We discuss and evaluate the representation of atmospheric chemistry in the global Community Atmosphere Model (CAM) version 4, the atmospheric component of the Community Earth System Model (CESM). We present a variety of configurations for the representation of tropospheric and stratospheric chemistry, wet removal, and online and offline meteorology. Results from simulations illustrating these configurations are compared with surface, aircraft and satellite observations. Major biases include a negative bias in the high-latitude CO distribution, a positive bias in upper-tropospheric/lower-stratospheric ozone, and a positive bias in summertime surface ozone (over the United States and Europe). The tropospheric net chemical ozone production varies significantly between configurations, partly related to variations in stratosphere-troposphere exchange. Aerosol optical depth tends to be underestimated over most regions, while comparison with aerosol surface measurements over the United States indicate reasonable results for sulfate, especially in the online simulation. Other aerosol species exhibit significant biases. Overall, the model-data comparison indicates that the offline simulation driven by GEOS5 meteorological analyses provides the best simulation, possibly due in part to the increased vertical resolution (52 levels instead of 26 for online dynamics). The CAM-chem code as described in this paper, along with all the necessary datasets needed to perform the simulations described here, are available for download at www.cesm.ucar.edu.

  1. Coupling the Community Atmospheric Model (CAM) with the Statistical Spectral Interpolation (SSI) System under ESMF

    NASA Technical Reports Server (NTRS)

    daSilva, Arlindo

    2004-01-01

    The first set of interoperability experiments illustrates the role ESMF can play in integrating the national Earth science resources. Using existing data assimilation technology from NCEP and the National Weather Service, the Community Atmosphere Model (CAM) was able to ingest conventional and remotely sensed observations, a capability that could open the door to using CAM for weather as well as climate prediction. CAM, which includes land surface capabilities, was developed by NCAR, with key components from GSFC. In this talk we will describe the steps necessary for achieving the coupling of these two systems.

  2. An assessment of atmospheric mercury in the Community Multiscale Air Quality (CMAQ) model

    NASA Astrophysics Data System (ADS)

    Holloway, T.; Voigt, C.; Morton, J.; Spak, S. N.; Rutter, A. P.; Schauer, J. J.

    2012-01-01

    Quantitative analysis of three atmospheric mercury species - gaseous elemental mercury (Hg0), reactive gaseous mercury (RGHg) and particulate mercury (PHg) - has been limited to date by lack of ambient measurement data as well as by uncertainties in numerical models and emission inventories. This study employs the Community Multiscale Air Quality Model version 4.6 with mercury chemistry (CMAQ-Hg), to examine how local emissions, meteorology, atmospheric chemistry, and deposition affect mercury concentration and deposition the Great Lakes Region (GLR), and two sites in Wisconsin in particular: the rural Devil's Lake site and the urban Milwaukee site. Ambient mercury exhibits significant biases at both sites. Hg0 is too low in CMAQ-Hg, with the model showing a 6% low bias at the rural site and 36% low bias at the urban site. Reactive mercury (RHg = RGHg + PHg) is over-predicted by the model, with annual average biases >250%. Performance metrics for RHg are much worse than for mercury wet deposition, ozone (O3), nitrogen dioxide (NO2), or sulfur dioxide (SO2). Sensitivity simulations to isolate background inflow from regional emissions suggests that oxidation of imported Hg0 dominates model estimates of RHg at the rural study site (91% of base case value), and contributes 55% to the RHg at the urban site (local emissions contribute 45%). Limited evidence on the lifetime of RHg transported to the rural site suggests that modeled dry deposition rates are too high, possibly compensating for the erroneously high RHg values.

  3. Convective organization in the super-parameterized community atmosphere model with constant surface temperature

    NASA Astrophysics Data System (ADS)

    Kuang, Z.

    2015-12-01

    Organization in a moist convecting atmosphere is investigated using the super-parameterized community atmosphere model (SPCAM) in aquaplanet setting with constant surface temperature, with and without planetary rotation. Without radiative and surface feedbacks, convective organization is dominated by convectively coupled gravity waves without planetary rotation and convectively coupled equatorial waves when there is planetary rotation. This behavior is well captured when the cloud resolving model (CRM) in SPCAM is replaced by its linear response function, computed following Kuang (2010), for the state of radiative convective equilibrium (RCE). With radiative feedback, however, convection self-aggregates, and with planetary rotation, the tropical zonal wavenumber-frequency spectrum features a red noise background. These behaviors in the presence of the radiative feedback are not captured when the CRM is replaced by its linear response function around the RCE state with radiative feedback included in the construction. Implications to organization in a moist convecting atmosphere will be discussed. Kuang, Z., Linear response functions of a cumulus ensemble to temperature and moisture perturbations and implication to the dynamics of convectively coupled waves, J. Atmos. Sci., 67, 941-962, (2010)

  4. Aerosol specification in single-column Community Atmosphere Model version 5

    NASA Astrophysics Data System (ADS)

    Lebassi-Habtezion, B.; Caldwell, P. M.

    2015-03-01

    Single-column model (SCM) capability is an important tool for general circulation model development. In this study, the SCM mode of version 5 of the Community Atmosphere Model (CAM5) is shown to handle aerosol initialization and advection improperly, resulting in aerosol, cloud-droplet, and ice crystal concentrations which are typically much lower than observed or simulated by CAM5 in global mode. This deficiency has a major impact on stratiform cloud simulations but has little impact on convective case studies because aerosol is currently not used by CAM5 convective schemes and convective cases are typically longer in duration (so initialization is less important). By imposing fixed aerosol or cloud-droplet and crystal number concentrations, the aerosol issues described above can be avoided. Sensitivity studies using these idealizations suggest that the Meyers et al. (1992) ice nucleation scheme prevents mixed-phase cloud from existing by producing too many ice crystals. Microphysics is shown to strongly deplete cloud water in stratiform cases, indicating problems with sequential splitting in CAM5 and the need for careful interpretation of output from sequentially split climate models. Droplet concentration in the general circulation model (GCM) version of CAM5 is also shown to be far too low (~ 25 cm-3) at the southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site.

  5. Aerosol specification in single-column Community Atmosphere Model version 5

    DOE PAGES

    Lebassi-Habtezion, B.; Caldwell, P. M.

    2015-03-27

    Single-column model (SCM) capability is an important tool for general circulation model development. In this study, the SCM mode of version 5 of the Community Atmosphere Model (CAM5) is shown to handle aerosol initialization and advection improperly, resulting in aerosol, cloud-droplet, and ice crystal concentrations which are typically much lower than observed or simulated by CAM5 in global mode. This deficiency has a major impact on stratiform cloud simulations but has little impact on convective case studies because aerosol is currently not used by CAM5 convective schemes and convective cases are typically longer in duration (so initialization is less important).more » By imposing fixed aerosol or cloud-droplet and crystal number concentrations, the aerosol issues described above can be avoided. Sensitivity studies using these idealizations suggest that the Meyers et al. (1992) ice nucleation scheme prevents mixed-phase cloud from existing by producing too many ice crystals. Microphysics is shown to strongly deplete cloud water in stratiform cases, indicating problems with sequential splitting in CAM5 and the need for careful interpretation of output from sequentially split climate models. Droplet concentration in the general circulation model (GCM) version of CAM5 is also shown to be far too low (~ 25 cm−3) at the southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site.« less

  6. Evaluating and improving cloud phase in the Community Atmosphere Model version 5 using spaceborne lidar observations

    NASA Astrophysics Data System (ADS)

    Kay, Jennifer E.; Bourdages, Line; Miller, Nathaniel B.; Morrison, Ariel; Yettella, Vineel; Chepfer, Helene; Eaton, Brian

    2016-04-01

    Spaceborne lidar observations from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite are used to evaluate cloud amount and cloud phase in the Community Atmosphere Model version 5 (CAM5), the atmospheric component of a widely used state-of-the-art global coupled climate model (Community Earth System Model). By embedding a lidar simulator within CAM5, the idiosyncrasies of spaceborne lidar cloud detection and phase assignment are replicated. As a result, this study makes scale-aware and definition-aware comparisons between model-simulated and observed cloud amount and cloud phase. In the global mean, CAM5 has insufficient liquid cloud and excessive ice cloud when compared to CALIPSO observations. Over the ice-covered Arctic Ocean, CAM5 has insufficient liquid cloud in all seasons. Having important implications for projections of future sea level rise, a liquid cloud deficit contributes to a cold bias of 2-3°C for summer daily maximum near-surface air temperatures at Summit, Greenland. Over the midlatitude storm tracks, CAM5 has excessive ice cloud and insufficient liquid cloud. Storm track cloud phase biases in CAM5 maximize over the Southern Ocean, which also has larger-than-observed seasonal variations in cloud phase. Physical parameter modifications reduce the Southern Ocean cloud phase and shortwave radiation biases in CAM5 and illustrate the power of the CALIPSO observations as an observational constraint. The results also highlight the importance of using a regime-based, as opposed to a geographic-based, model evaluation approach. More generally, the results demonstrate the importance and value of simulator-enabled comparisons of cloud phase in models used for future climate projection.

  7. CMAQ (Community Multi-Scale Air Quality) atmospheric distribution model adaptation to region of Hungary

    NASA Astrophysics Data System (ADS)

    Lázár, Dóra; Weidinger, Tamás

    2016-04-01

    For our days, it has become important to measure and predict the concentration of harmful atmospheric pollutants such as dust, aerosol particles of different size ranges, nitrogen compounds, and ozone. The Department of Meteorology at Eötvös Loránd University has been applying the WRF (Weather Research and Forecasting) model several years ago, which is suitable for weather forecasting tasks and provides input data for various environmental models (e.g. DNDC). By adapting the CMAQ (Community Multi-scale Air Quality) model we have designed a combined ambient air-meteorological model (WRF-CMAQ). In this research it is important to apply different emission databases and a background model describing the initial distribution of the pollutant. We used SMOKE (Sparse Matrix Operator Kernel Emissions) model for construction emission dataset from EMEP (European Monitoring and Evaluation Programme) inventories and GEOS-Chem model for initial and boundary conditions. Our model settings were CMAQ CB05 (Carbon Bond 2005) chemical mechanism with 108 x 108 km, 36 x 36 km and 12 x 12 km grids for regions of Europe, the Carpathian Basin and Hungary respectively. i) The structure of the model system, ii) a case study for Carpathian Basin (an anticyclonic weather situation at 21th September 2012) are presented. iii) Verification of ozone forecast has been provided based on the measurements of background air pollution stations. iv) Effects of model attributes (f.e. transition time, emission dataset, parameterizations) for the ozone forecast in Hungary are also investigated.

  8. The Implementation of the Finite-Volume Dynamical Core in the Community Atmosphere Model

    SciTech Connect

    Sawyer, W B; Mirin, A A

    2005-07-26

    A distributed memory message-passing parallel implementation of a finite-volume discretization of the primitive equations in the Community Atmosphere Model 3.0 is presented. These three-dimensional equations can be decoupled into a set of two-dimensional equations by the introduction of a floating vertical coordinate, resulting in considerable potential parallelism. Subsequent analysis of the data dependencies --in particular those arising from the polar singularity of the latitude-longitude coordinate system--suggests that two separate domain decompositions should be employed, each tailored for a different part of the model. The implementation requires that data be periodically redistributed between these two decompositions. Furthermore, data from nearest neighbors are kept in halo regions, which are updated between iterations. These data movements are optimized through one-sided communication primitives and multithreading. The resulting algorithm is shown to scale to very large machine configurations, even for relatively coarse resolutions.

  9. The Implementation of the Finite-Volume Dynamical Core in the Community Atmosphere Model

    SciTech Connect

    Sawyer, W B; Mirin, A A

    2004-11-30

    A distributed memory message-passing parallel implementation of a finite-volume discretization of the primitive equations in the Community Atmosphere Model is presented. These three-dimensional equations can be decoupled into a set of two-dimensional equations by the introduction of a floating vertical coordinate, resulting in considerable potential parallelism. Subsequent analysis of the data dependencies--in particular those arising from the polar singularity of the latitude-longitude coordinate system--suggests that two separate domain decompositions should be employed, each tailored for a different part of the model. The implementation requires that data be periodically redistributed between these two decompositions. Furthermore, data from nearest neighbors are kept in halo regions, which are updated between iterations. These data movements are optimized through one-sided communication primitives and multithreading. The resulting algorithm is shown to scale to very large machine configurations, even for relatively coarse resolutions.

  10. A spectral transform dynamical core option within the Community Atmosphere Model (CAM4)

    SciTech Connect

    Evans, Katherine J; Mahajan, Salil; Branstetter, Marcia L; McClean, Julie L.; Caron, Julie M.; Maltrud, Matthew E.; Hack, James J; Bader, David C; Neale, Rich

    2014-01-01

    A spectral transform dynamical core with an 85 spectral truncation resolution (T85) within the Community Atmosphere Model (CAM), version 4, is evaluated within the recently released Community Earth System Model, version 1.0 (CESM) global climate model. The spectral dynamical core option provides a well-known base within the climate model community from which to assess climate behavior and statistics, and its relative computational efficiency for smaller computing platforms allows it to be extended to perform climate length simulations using high-resolution configurations in the near term. To establish the characteristics of the CAM4 T85, an ensemble of simulations covering the present day observational period using forced sea surface temperatures and prescribed sea-ice extent are evaluated. Overall, the T85 ensemble attributes and biases are similar to a companion ensemble of simulations using the one degree finite volume (FV1) dynamical core, relative to observed and model derived datasets. Notable improvements with T85 compared to FV1 include the representation of wintertime Arctic sea level pressure and summer precipitation over the Western Indian subcontinent. The mean and spatial patterns of the land surface temperature trends over the AMIP period are generally well simulated with the T85 ensemble relative to observations, however the model is not able to capture the extent nor magnitude of changes in temperature extremes over the boreal summer, where the changes are most dramatic. Biases in the wintertime Arctic surface temperature and annual mean surface stress fields persist with T85 as with the CAM3 version of T85.

  11. CAM-SE: A scalable spectral element dynamical core for the Community Atmosphere Model.

    SciTech Connect

    Dennis, John; Edwards, Jim; Evans, Kate J; Guba, O; Lauritzen, Peter; Mirin, Art; St.-Cyr, Amik; Taylor, Mark; Worley, Patrick H

    2012-01-01

    The Community Atmosphere Model (CAM) version 5 includes a spectral element dynamical core option from NCAR's High-Order Method Modeling Environment. It is a continuous Galerkin spectral finite element method designed for fully unstructured quadrilateral meshes. The current configurations in CAM are based on the cubed-sphere grid. The main motivation for including a spectral element dynamical core is to improve the scalability of CAM by allowing quasi-uniform grids for the sphere that do not require polar filters. In addition, the approach provides other state-of-the-art capabilities such as improved conservation properties. Spectral elements are used for the horizontal discretization, while most other aspects of the dynamical core are a hybrid of well tested techniques from CAM's finite volume and global spectral dynamical core options. Here we first give a overview of the spectral element dynamical core as used in CAM. We then give scalability and performance results from CAM running with three different dynamical core options within the Community Earth System Model, using a pre-industrial time-slice configuration. We focus on high resolution simulations of 1/4 degree, 1/8 degree, and T340 spectral truncation.

  12. A scalable implementation of a finite-volume dynamical core in the Community Atmosphere Model

    SciTech Connect

    Mirin, A A; Sawyer, W B

    2004-09-24

    A distributed memory message-passing parallel implementation of a finite-volume discretization of the primitive equations in the Community Atmosphere Model is presented. Due to the data dependencies resulting from the polar singularity of the latitude-longitude coordinate system, we employ two separate domain decompositions within the dynamical core--one in latitude/level space, and the other in longitude/latitude space. This requires that the data be periodically redistributed between these two decompositions. In addition, the domains contain halo regions that cover the nearest neighbor data dependencies. A combination of several techniques, such as one-sided communication and multithreading, are presented to optimize data movements. The resulting algorithm is shown to scale to very large machine configurations, even for relatively coarse resolutions.

  13. A Scalable Implementation of a Finite-Volume Dynamical Core in the Community Atmosphere Model

    SciTech Connect

    Sawyer, W; Mirin, A

    2004-06-25

    A distributed memory message-passing parallel implementation of a finite-volume discretization of the primitive equations in the Community Atmosphere Model is presented. Due to the data dependencies resulting from the polar singularity of the latitude-longitude coordinate system, it is necessary to employ two separate domain decompositions within the dynamical core. Data must be periodically redistributed between these two decompositions. In addition, the domains contain halo regions that cover the nearest neighbor data dependencies. A combination of several techniques, such as one-sided communication and multithreading, are presented to optimize data movements. The resulting algorithm is shown to scale to very large machine configurations, even for relatively coarse resolutions.

  14. Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing

    DOE PAGES

    Scanza, Rachel; Mahowald, N.; Ghan, Steven J.; ...

    2015-01-01

    The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale, using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral componentsmore » in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as + 0.05 Wm⁻² for both CAM4 and CAM5 simulations with mineralogy. We compare this to the radiative forcing from simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 Wm⁻²) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, -0.05 and -0.17 Wm⁻², respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.« less

  15. Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing

    DOE PAGES

    Scanza, R. A.; Mahowald, N.; Ghan, S.; ...

    2014-07-02

    The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral componentsmore » in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as +0.05 W m−2 for both CAM4 and CAM5 simulations with mineralogy and compare this both with simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 W m−2) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, −0.05 and −0.17 W m−2, respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in-situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.« less

  16. “World avoided” simulations with the Whole Atmosphere Community Climate Model

    NASA Astrophysics Data System (ADS)

    Garcia, Rolando R.; Kinnison, Douglas E.; Marsh, Daniel R.

    2012-12-01

    We use the Whole Atmosphere Community Climate Model, coupled to a deep ocean model, to investigate the impact of continued growth of halogenated ozone depleting substances (ODS) in the absence of the Montreal Protocol. We confirm the previously reported result that the growth of ODS leads to a global collapse of the ozone layer in mid-21st century, with column amounts falling to 100 DU or less at all latitudes. We also show that heterogeneous activation of chlorine in the lower stratosphere hastens this collapse but is not essential to produce it. The growth of ODS, which are also greenhouse gases, produces a radiative forcing of 4 W m-2by 2070, nearly equal that of the non-ODS greenhouse gases CO2, CH4, and N2O in the RCP4.5 scenario of IPCC. This leads to surface warming of over 2 K in the tropics, 6 K in the Arctic, and close to 4 K in Antarctica in 2070 compared to the beginning of the century. We explore the reversibility of these impacts following complete cessation of ODS emissions in the mid-2050s. We find that impacts are reversed on various time scales, depending on the atmospheric lifetime of the ODS that cause them. Thus ozone in the lower stratosphere in the tropics and subtropics recovers very quickly because the ODS that release chlorine and bromine there (e.g., methyl chloroform and methyl bromide) have short atmospheric lifetimes and are removed within a few years. On the other hand, ozone depletion in the polar caps and global radiative forcing depend on longer-lived ODS, such that much of these impacts persist through the end of our simulations in 2070.

  17. Boreal Winter MJO Teleconnection in the Community Atmosphere Model Version 5 with the Unified Convection Parameterization

    SciTech Connect

    Yoo, Changhyun; Park, Sungsu; Kim, Daehyun; Yoon, Jin-Ho; Kim, Hye-Mi

    2015-10-01

    The Madden-Julian Oscillation (MJO), the dominant mode of tropical intraseasonal variability, influences weather and climate in the extratropics through atmospheric teleconnection. In this study, two simulations using the Community Atmosphere Model version 5 (CAM5) - one with the default shallow and deep convection schemes and the other with the Unified Convection scheme (UNICON) - are employed to examine the impacts of cumulus parameterizations on the simulation of the boreal wintertime MJO teleconnection in the Northern Hemisphere. We demonstrate that the UNICON substantially improves the MJO teleconnection. When the UNICON is employed, the simulated circulation anomalies associated with the MJO better resemble the observed counterpart, compared to the simulation with the default convection schemes. Quantitatively, the pattern correlation for the 300-hPa geopotential height anomalies between the simulations and observation increases from 0.07 for the default schemes to 0.54 for the UNICON. These circulation anomalies associated with the MJO further help to enhance the surface air temperature and precipitation anomalies over North America, although room for improvement is still evident. Initial value calculations suggest that the realistic MJO teleconnection with the UNICON is not attributed to the changes in the background wind, but primarily to the improved tropical convective heating associated with the MJO.

  18. Land-total and Ocean-total Precipitation and Evaporation from a Community Atmosphere Model version 5 Perturbed Parameter Ensemble

    SciTech Connect

    Covey, Curt; Lucas, Donald D.; Trenberth, Kevin E.

    2016-03-02

    This document presents the large scale water budget statistics of a perturbed input-parameter ensemble of atmospheric model runs. The model is Version 5.1.02 of the Community Atmosphere Model (CAM). These runs are the “C-Ensemble” described by Qian et al., “Parametric Sensitivity Analysis of Precipitation at Global and Local Scales in the Community Atmosphere Model CAM5” (Journal of Advances in Modeling the Earth System, 2015). As noted by Qian et al., the simulations are “AMIP type” with temperature and sea ice boundary conditions chosen to match surface observations for the five year period 2000-2004. There are 1100 ensemble members in addition to one run with default inputparameter values.

  19. A New Ensemble of Perturbed-Input-Parameter Simulations by the Community Atmosphere Model

    SciTech Connect

    Covey, C; Brandon, S; Bremer, P T; Domyancis, D; Garaizar, X; Johannesson, G; Klein, R; Klein, S A; Lucas, D D; Tannahill, J; Zhang, Y

    2011-10-27

    Uncertainty quantification (UQ) is a fundamental challenge in the numerical simulation of Earth's weather and climate, and other complex systems. It entails much more than attaching defensible error bars to predictions: in particular it includes assessing low-probability but high-consequence events. To achieve these goals with models containing a large number of uncertain input parameters, structural uncertainties, etc., raw computational power is needed. An automated, self-adapting search of the possible model configurations is also useful. Our UQ initiative at the Lawrence Livermore National Laboratory has produced the most extensive set to date of simulations from the US Community Atmosphere Model. We are examining output from about 3,000 twelve-year climate simulations generated with a specialized UQ software framework, and assessing the model's accuracy as a function of 21 to 28 uncertain input parameter values. Most of the input parameters we vary are related to the boundary layer, clouds, and other sub-grid scale processes. Our simulations prescribe surface boundary conditions (sea surface temperatures and sea ice amounts) to match recent observations. Fully searching this 21+ dimensional space is impossible, but sensitivity and ranking algorithms can identify input parameters having relatively little effect on a variety of output fields, either individually or in nonlinear combination. Bayesian statistical constraints, employing a variety of climate observations as metrics, also seem promising. Observational constraints will be important in the next step of our project, which will compute sea surface temperatures and sea ice interactively, and will study climate change due to increasing atmospheric carbon dioxide.

  20. Quantifying the effect of parameter uncertainties on the simulation of drought in the Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Anderson, G. J.; Bonfils, C.; Lucas, D. D.; Santer, B. D.

    2015-12-01

    Over the 21st century, anthropogenic climate change is expected to increase the occurrence of extreme droughts, leading to significant socio-economic impacts in many regions of the world. The precursors of drought are diverse and still poorly understood. Climate models provide useful tools for studying the physical links between precursor "drought-conducive" climatic states and the characteristics of drought, such as severity, duration, spatial extent and frequency. There are, however, still large uncertainties in model portrayal of the physical processes governing drought behavior. Reducing these uncertainties is a necessary but not sufficient condition for enhancing confidence in model projections of 21st century changes in drought. Here, we analyze a large (1300-member) perturbed physics ensemble performed with the Community Atmospheric Model (CAM4) to gain insights into causes of the 1998-2002 North American drought. The ensemble was constructed by varying the values of input parameters related to clouds, precipitation, convection, and the boundary layer over allowable ranges of uncertainty. Changes in these parameters can alter the width of the Hadley circulation, strengthen deep convection, and perturb land-atmospheric coupling, leading to different predictions of temperature, precipitation and soil moisture, and, in turn, very different simulations of drought properties. We perform a sensitivity analysis to identify the key parameters influencing drought-related metrics. Using observations and a Bayesian statistical framework, we identify parameter values that yield a better fit to data, thereby identifying configurations that may be more successful in simulating key features of observed drought behavior. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and is released as LLNL-ABS675834. It is supported by the Early Career Research Program awarded to Celine

  1. Trade-wind Clouds in Community Atmosphere Model Hindcasts: Impacts of Resolution and Parameterized Physics

    NASA Astrophysics Data System (ADS)

    Medeiros, B.

    2016-12-01

    Shallow cumulus clouds predominate in the trade-wind regions and the response of this widespread regime has been directly linked to the spread in climate model estimates of cloud feedback and climate sensitivity. Observations and process-model simulations show that trade-wind regions foster multi-layered cloud structures with complicated relationships to their environment that manifest as different cloud variability near the cloud base versus cloud top as well as inhomogeneous horizontal distributions of cloud. Assessments of these clouds in climate models show a disturbing spread among models in the vertical structure, but much less spread in the cloud radiative effect signaling compensating biases. The models also fail to capture the observed correlations between clouds and environmental parameters, often showing the opposite sign compared to observations. Based on such errors, one hypothesis is that climate models lack the proper parameterized physics to represent shallow convection. An alternate hypothesis is that models do not capture observed mesoscale variability, leading to erroneous cloud statistics. Of course, the hypotheses are not mutually exclusive. A series of hindcasts are performed with the Community Atmosphere Model to test these hypotheses. One set of hindcasts uses the standard 1-degree grid spacing, and it is shown that the clouds are similar to long-term, free-running simulations. A parallel set of hindcasts with a refined 0.25-degree mesh over the northern Atlantic trade-wind region allows a detailed comparison of the model's ability to represent trade-wind clouds with and without mesoscale variability explicitly resolved. Two more sets of hindcasts are run with the same grid configurations but using updated parameterized physics that change the representation of clouds, turbulence, and shallow convection. The updated physics are nominally less sensitive to horizontal resolution, which is tested by comparing the coarse and fine resolution, and

  2. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; Goldhaber, S.; Bogenschutz, P. A.; Chen, C.-C.; Morrison, H.; Höft, J.; Raut, E.; Griffin, B. M.; Weber, J. K.; Larson, V. E.; Wyant, M. C.; Wang, M.; Guo, Z.; Ghan, S. J.

    2015-12-01

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points into a microphysics scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Model computational expense is estimated, and sensitivity to the number of subcolumns is investigated. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in shortwave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation.

  3. Biosphere-Atmosphere Transfer Scheme (BATS) version le as coupled to the NCAR community climate model. Technical note. [NCAR (National Center for Atmospheric Research)

    SciTech Connect

    Dickinson, R.E.; Henderson-Sellers, A.; Kennedy, P.J.

    1993-08-01

    A comprehensive model of land-surface processes has been under development suitable for use with various National Center for Atmospheric Research (NCAR) General Circulation Models (GCMs). Special emphasis has been given to describing properly the role of vegetation in modifying the surface moisture and energy budgets. The result of these efforts has been incorporated into a boundary package, referred to as the Biosphere-Atmosphere Transfer Scheme (BATS). The current frozen version, BATS1e is a piece of software about four thousand lines of code that runs as an offline version or coupled to the Community Climate Model (CCM).

  4. Immersion freezing by natural dust based on a soccer ball model with the Community Atmospheric Model version 5: climate effects

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Liu, Xiaohong

    2014-12-01

    We introduce a simplified version of the soccer ball model (SBM) developed by Niedermeier et al (2014 Geophys. Res. Lett. 41 736-741) into the Community Atmospheric Model version 5 (CAM5). It is the first time that SBM is used in an atmospheric model to parameterize the heterogeneous ice nucleation. The SBM, which was simplified for its suitable application in atmospheric models, uses the classical nucleation theory to describe the immersion/condensation freezing by dust in the mixed-phase cloud regime. Uncertain parameters (mean contact angle, standard deviation of contact angle probability distribution, and number of surface sites) in the SBM are constrained by fitting them to recent natural dust (Saharan dust) datasets. With the SBM in CAM5, we investigate the sensitivity of modeled cloud properties to the SBM parameters, and find significant seasonal and regional differences in the sensitivity among the three SBM parameters. Changes of mean contact angle and the number of surface sites lead to changes of cloud properties in Arctic in spring, which could be attributed to the transport of dust ice nuclei to this region. In winter, significant changes of cloud properties induced by these two parameters mainly occur in northern hemispheric mid-latitudes (e.g., East Asia). In comparison, no obvious changes of cloud properties caused by changes of standard deviation can be found in all the seasons. These results are valuable for understanding the heterogeneous ice nucleation behavior, and useful for guiding the future model developments.

  5. A new multi-tracer transport scheme for the dynamical core of NCAR's Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Erath, C.

    2012-04-01

    The integration of a conservative semi-Lagrangian multi-tracer transport scheme (CSLAM) in NCAR's High-Order Method Modeling Environment (HOMME) is considered here. HOMME is a highly scalable atmospheric modeling framework, and its current horizontal discretization relies on spectral element (SE) and/or discontinuous Galerkin (DG) methods on the cubed-sphere. It is one dynamical core of NCAR's Community Atmosphere Model (CAM). The main advantage of CSLAM is that the upstream cell (trajectories) information and computation of weights of integrals can be reused for each additional tracer. This makes CSLAM particularly interesting for global atmospheric modeling with growing number of tracers, e.g. more than 100 tracers for the chemistry version of CAM. An algorithm specifically designed for multiple processors and on the cubed-sphere grid for CSLAM in HOMME is a challenging task. HOMME is running on an element ansatz on the six cube faces. Inside these elements we create an Eulerian finite volume grid of equiangular gnomonic type, which represents the arrival grid in the scheme. But CSLAM relies on backward trajectories, which entails a departure grid. That means departure and arrival grid don't necessary have to be on the same element and certainly not on the same cube face. Also the reconstruction for higher order modeling needs a patch of tracer values which extend the element. Here we consider a third order reconstruction method. Therefore, we introduce a halo for the tracer values in the cell centers of a cube-element. The size of this halo depends on the Courant number (CFL condition) and the reconstruction type. Note that for a third order scheme and CFL number < 1 we need at least a halo size four (four values in the halo in one direction). But the communication can be limited to one per time step. This data structure allows us to consider an element with its halo as one task where we have to be extra carful for elements which share a cube edge due to

  6. Uniformly rotating global radiative-convective equilibrium in the Community Atmosphere Model, version 5

    NASA Astrophysics Data System (ADS)

    Reed, Kevin A.; Chavas, Daniel R.

    2015-12-01

    A standard atmospheric general circulation model is run in a uniformly rotating global radiative-convective equilibrium configuration to explore the equilibrium state, including the statistics of its constituent tropical cyclones, and its sensitivity to horizontal resolution. The Community Atmosphere Model 5 (CAM5) is run at the conventional resolution of approximately 100 km grid spacing and a high resolution of 25 km grid spacing globally. The setup uses an aqua-planet configuration with spatially uniform, diurnally varying insolation, uniform fixed sea surface temperatures, and a uniform rotation rate equal to that at 10°N. The resulting state is one in which tropical cyclones fill the global domain, such that storm count and outer storm size covary strongly. At higher resolution, the storm inner core is more intense and compact but the size of the outer circulation decreases only marginally, and storm count increases in a manner consistent with this decrease in size. Furthermore, the size of the wind field and precipitation fields are highly correlated. A simple analytical model is found to robustly reproduce the radial structure of the broad outer storm circulation. Finally, the minimum central pressure is demonstrated to be an exclusive function of peak azimuthal-mean wind speed and outer storm size. Despite significant changes in the statistics of storm count, intensity, and structure, the mean environment, including the potential intensity, is nearly identical for both simulations. Results are compared with the nonrotating case from a prior study, and a generalized conceptual framework for the interpretation of aggregation with or without rotation is proposed.

  7. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    DOE PAGES

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; ...

    2015-06-30

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points into amore » microphysics scheme.This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation. Also presented are estimations of computational expense and investigation of sensitivity to number of subcolumns.« less

  8. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    DOE PAGES

    Thayer-Calder, Katherine; Gettelman, A.; Craig, Cheryl; ...

    2015-12-01

    Most global climate models parameterize separate cloud types using separate parameterizations.This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points into a microphysicsmore » scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Results describing the mean climate and tropical variability from global simulations are presented. In conclusion, the new model shows a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, perceptible water, and tropical wave simulation. Also presented are estimations of computational expense and investigation of sensitivity to number of subcolumns.« less

  9. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; Goldhaber, S.; Bogenschutz, P. A.; Chen, C.-C.; Morrison, H.; Höft, J.; Raut, E.; Griffin, B. M.; Weber, J. K.; Larson, V. E.; Wyant, M. C.; Wang, M.; Guo, Z.; Ghan, S. J.

    2015-06-01

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points into a microphysics scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation. Also presented are estimations of computational expense and investigation of sensitivity to number of subcolumns.

  10. Inclusion of Ice Microphysics in the NCAR Community Atmospheric Model Version 3 (CAM3)

    SciTech Connect

    Liu, Xiaohong; Penner, Joyce E.; Ghan, Steven J.; Wang, M.

    2007-09-15

    A prognostic equation for ice crystal number concentration together with an ice nucleation scheme are implemented in the National Center for Atmospheric Research (NCAR) Community Atmospheric Model Version 3 (CAM3) with the aim of studying the indirect effect of aerosols on cold clouds. The effective radius of ice crystals which is used in the radiation and gravitational settlement calculations is now calculated from model predicted mass and number of ice crystals rather than diagnosed as a function of temperature. We add a water vapor deposition scheme to replace the condensation and evaporation (C-E) in the standard CAM3 for ice clouds. The repartitioning of total water into liquid and ice in mixed-phase clouds as a function of temperature is removed, and ice supersaturation is allowed. The predicted ice water content in the modified CAM3 is in better agreement with the Aura MLS data than that in the standard CAM3. The cirrus cloud fraction near the tropical tropopause, which is underestimated in the standard CAM3, is increased, and the cold temperature bias there is reduced by 1-2 °K. However, an increase in the cloud fraction in polar regions makes the underestimation of downwelling shortwave radiation in the standard CAM3 even worse. A sensitivity test reducing the threshold relative humidity with respective to ice (RHi) for heterogeneous ice nucleation from 120% to 105% (representing nearly perfert ice nuclei) increases the global cloud cover by 1.7%, temperature near the tropical tropopause by 4-5 °K, and water vapor in the stratosphere by 50-90%.

  11. Parametric behaviors of CLUBB in simulations of low clouds in the Community Atmosphere Model (CAM)

    DOE PAGES

    Guo, Zhun; Wang, Minghuai; Qian, Yun; ...

    2015-07-03

    In this study, we investigate the sensitivity of simulated low clouds to 14 selected tunable parameters of Cloud Layers Unified By Binormals (CLUBB), a higher order closure (HOC) scheme, and 4 parameters of the Zhang-McFarlane (ZM) deep convection scheme in the Community Atmosphere Model version 5 (CAM5). A quasi-Monte Carlo (QMC) sampling approach is adopted to effectively explore the high-dimensional parameter space and a generalized linear model is applied to study the responses of simulated cloud fields to tunable parameters. Our results show that the variance in simulated low-cloud properties (cloud fraction and liquid water path) can be explained bymore » the selected tunable parameters in two different ways: macrophysics itself and its interaction with microphysics. First, the parameters related to dynamic and thermodynamic turbulent structure and double Gaussians closure are found to be the most influential parameters for simulating low clouds. The spatial distributions of the parameter contributions show clear cloud-regime dependence. Second, because of the coupling between cloud macrophysics and cloud microphysics, the coefficient of the dissipation term in the total water variance equation is influential. This parameter affects the variance of in-cloud cloud water, which further influences microphysical process rates, such as autoconversion, and eventually low-cloud fraction. Furthermore, this study improves understanding of HOC behavior associated with parameter uncertainties and provides valuable insights for the interaction of macrophysics and microphysics.« less

  12. Parametric behaviors of CLUBB in simulations of low clouds in the Community Atmosphere Model (CAM)

    SciTech Connect

    Guo, Zhun; Wang, Minghuai; Qian, Yun; Larson, Vincent E.; Ghan, Steven; Ovchinnikov, Mikhail; A. Bogenschutz, Peter; Gettelman, Andrew; Zhou, Tianjun

    2015-07-03

    In this study, we investigate the sensitivity of simulated low clouds to 14 selected tunable parameters of Cloud Layers Unified By Binormals (CLUBB), a higher order closure (HOC) scheme, and 4 parameters of the Zhang-McFarlane (ZM) deep convection scheme in the Community Atmosphere Model version 5 (CAM5). A quasi-Monte Carlo (QMC) sampling approach is adopted to effectively explore the high-dimensional parameter space and a generalized linear model is applied to study the responses of simulated cloud fields to tunable parameters. Our results show that the variance in simulated low-cloud properties (cloud fraction and liquid water path) can be explained by the selected tunable parameters in two different ways: macrophysics itself and its interaction with microphysics. First, the parameters related to dynamic and thermodynamic turbulent structure and double Gaussians closure are found to be the most influential parameters for simulating low clouds. The spatial distributions of the parameter contributions show clear cloud-regime dependence. Second, because of the coupling between cloud macrophysics and cloud microphysics, the coefficient of the dissipation term in the total water variance equation is influential. This parameter affects the variance of in-cloud cloud water, which further influences microphysical process rates, such as autoconversion, and eventually low-cloud fraction. Furthermore, this study improves understanding of HOC behavior associated with parameter uncertainties and provides valuable insights for the interaction of macrophysics and microphysics.

  13. Parametric behaviors of CLUBB in simulations of low clouds in the Community Atmosphere Model (CAM)

    NASA Astrophysics Data System (ADS)

    Guo, Zhun; Wang, Minghuai; Qian, Yun; Larson, Vincent E.; Ghan, Steven; Ovchinnikov, Mikhail; Bogenschutz, Peter A.; Gettelman, Andrew; Zhou, Tianjun

    2015-09-01

    In this study, we investigate the sensitivity of simulated low clouds to 14 selected tunable parameters of Cloud Layers Unified By Binormals (CLUBB), a higher-order closure (HOC) scheme, and four parameters of the Zhang-McFarlane (ZM) deep convection scheme in the Community Atmosphere Model version 5 (CAM5). A Quasi-Monte Carlo (QMC) sampling approach is adopted to effectively explore the high-dimensional parameter space and a generalized linear model is applied to study the responses of simulated cloud fields to tunable parameters. Our results show that the variance in simulated low-cloud properties (cloud fraction and liquid water path) can be explained by the selected tunable parameters in two different ways: macrophysics itself and its interaction with microphysics. First, the parameters related to dynamic and thermodynamic turbulent structure and double Gaussian closure are found to be the most influential parameters for simulating low clouds. The spatial distributions of the parameter contributions show clear cloud-regime dependence. Second, because of the coupling between cloud macrophysics and cloud microphysics, the coefficient of the dissipation term in the total water variance equation is influential. This parameter affects the variance of in-cloud cloud water, which further influences microphysical process rates, such as autoconversion, and eventually low-cloud fraction. This study improves understanding of HOC behavior associated with parameter uncertainties and provides valuable insights for the interaction of macrophysics and microphysics.

  14. Toward a more efficient and scalable checkpoint/restart mechanism in the Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Anantharaj, Valentine

    2015-04-01

    The number of cores (both CPU as well as accelerator) in large-scale systems has been increasing rapidly over the past several years. In 2008, there were only 5 systems in the Top500 list that had over 100,000 total cores (including accelerator cores) whereas the number of system with such capability has jumped to 31 in Nov 2014. This growth however has also increased the risk of hardware failure rates, necessitating the implementation of fault tolerance mechanism in applications. The checkpoint and restart (C/R) approach is commonly used to save the state of the application and restart at a later time either after failure or to continue execution of experiments. The implementation of an efficient C/R mechanism will make it more affordable to output the necessary C/R files more frequently. The availability of larger systems (more nodes, memory and cores) has also facilitated the scaling of applications. Nowadays, it is more common to conduct coupled global climate simulation experiments at 1 deg horizontal resolution (atmosphere), often requiring about 103 cores. At the same time, a few climate modeling teams that have access to a dedicated cluster and/or large scale systems are involved in modeling experiments at 0.25 deg horizontal resolution (atmosphere) and 0.1 deg resolution for the ocean. These ultrascale configurations require the order of 104 to 105 cores. It is not only necessary for the numerical algorithms to scale efficiently but the input/output (IO) mechanism must also scale accordingly. An ongoing series of ultrascale climate simulations, using the Titan supercomputer at the Oak Ridge Leadership Computing Facility (ORNL), is based on the spectral element dynamical core of the Community Atmosphere Model (CAM-SE), which is a component of the Community Earth System Model and the DOE Accelerated Climate Model for Energy (ACME). The CAM-SE dynamical core for a 0.25 deg configuration has been shown to scale efficiently across 100,000 cpu cores. At this

  15. Global analysis of parametric sensitivity of precipitation in the Community Atmosphere Model (CAM5)

    NASA Astrophysics Data System (ADS)

    Qian, Y.; Yan, H.; Zhao, C.; Hou, Z.; Wang, H.; Rasch, P. J.; Klein, S. A.; Lucas, D.; Tannahill, J.

    2013-12-01

    In this study, we investigate the sensitivity of precipitation characteristics, including mean, extreme and diurnal cycle, to dozens of uncertain parameters mainly related to cloud and aerosol processes in the Community Atmosphere Model (CAM5). We adopt both the Latin hypercube sampling and quasi-Monte Carlo sampling approaches to effectively explore the high-dimensional parameter space and then conduct two large sets of simulations (1356 in total). The CAM5 ensemble simulates the mean precipitation reasonably well, but fails to capture the diurnal cycle of precipitation over land. The phase of diurnal precipitation associated with the convection propagation over Central US seems to be more related to model structural errors rather than the parametric uncertainties. Parametric calibration could possibly improve CAM5 precipitation over regions, such as Tropical Western Pacific, having relatively weak diurnal cycle and high model parameter identifiability. The precipitation variance is large and the diurnal cycle is strong over South America and Central Africa, where parametric calibration can possibly improve the model prediction of mean precipitation but not the diurnal cycle. Variance-based sensitivity analysis using a generalized linear model (GLM) is conducted to examine the relative contributions of individual parameter perturbations and their interactions to the global and regional precipitation. We characterize the global spatial distribution as well as scale (global vs. local) and seasonal dependence of parametric sensitivity of precipitation, and identify a few parameters that dominate the behavior of the mean, extremes or diurnal cycle of precipitation, respectively. Results suggest that the model-simulated precipitation is remarkably sensitive to a few cloud-related parameters, while aerosols have minor impact on the diurnal cycle of precipitation in the current CAM5. The interactions among the selected parameters contribute a relatively small portion to

  16. Midlatitude atmospheric responses to Arctic sensible heat flux anomalies in Community Climate Model, Version 4: Atmospheric Response to Arctic SHFs

    SciTech Connect

    Mills, Catrin M.; Cassano, John J.; Cassano, Elizabeth N.

    2016-12-10

    Possible linkages between Arctic sea ice loss and midlatitude weather are strongly debated in the literature. We analyze a coupled model simulation to assess the possibility of Arctic ice variability forcing a midlatitude response, ensuring consistency between atmosphere, ocean, and ice components. We work with weekly running mean daily sensible heat fluxes with the self-organizing map technique to identify Arctic sensible heat flux anomaly patterns and the associated atmospheric response, without the need of metrics to define the Arctic forcing or measure the midlatitude response. We find that low-level warm anomalies during autumn can build planetary wave patterns that propagate downstream into the midlatitudes, creating robust surface cold anomalies in the eastern United States.

  17. The Sensitivity of Simulated Tropical Cyclones to Tunable Physical Parameters in Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    He, F.; Posselt, D. J.

    2014-12-01

    The inability to explicitly resolve the sub-grid scale physical processes (e.g. cloud, precipitation and convection) of atmospheric general circulation models (AGCMs) greatly limits their performance in simulating tropical cyclones (TCs) and predicting their future changes. To address it, this study carried out a total of 92 simulations and investigated the sensitivity of TC simulation to 24 physical parameters that control the deep convection, shallow convection, turbulence, cloud microphysics and cloud macrophysics processes in Community Atmosphere Model version 5 (CAM5). The Reed-Jablonowski TC test case is utilized and run at horizontal resolution of 0.5°×0.5° with 30 vertical levels. The sensitivity is assessed by the uncertainty each parameter exerts on simulated TC while perturbing it from its minimum to maximum with other 23 parameters set to their default value. The uncertainty is characterized by changes on simulated TC intensity (measured by absolute maximum wind speed at 100 m above surface), precipitation rate, shortwave cloud radiative forcing (SWCF), longwave cloud radiative forcing (LWCF), cloud liquid water path (LWP) and cloud ice water path (IWP), the latter five of which are quantified by their area-weighted value over the tropical cyclone region. Both the relative importance among these 24 physical parameters on TC simulation and the response function describing how they affect the six TC characteristics are quantified. It is found that the simulated TC intensity is most sensitive to the parcel fractional mass entrainment rate in Zhang-McFarlane (ZM) deep convection scheme. Decreasing this parameter enables a change from tropical depression to Category-4 storm. In contrast, other 23 physical parameters cause intensity uncertainty within 10 m/s. The precipitation rate, SWCF, LWP and IWP are also found to receive major impact from parameters in ZM deep convection scheme while the LWCF is dominated by parameters both in ZM deep convection and

  18. Modelling simulations of NOx and HOx in the middle and upper atmosphere using a 3D Whole Atmosphere Community Climate Model with D region ion-neutral chemistry

    NASA Astrophysics Data System (ADS)

    Feng, W.; Plane, J. M. C.; Kovacs, T.; Chipperfield, M.; Marsh, D. R.; Smith, A. K.; Verronen, P. T.; Newnham, D.; Clilverd, M. A.

    2016-12-01

    In the middle and upper atmosphere, the distributions of odd nitrogen NOx (NO, NO2) and odd hydrogen HOx (OH, HO2) are controlled by transport processes and chemistry. Energetic particle precipitation (of protons and electrons) produces NOx and HOx through ion-molecule chemistry, and this can play an important role in the chemistry of the mesosphere. There is also increasing evidence that the descent of NOx can destroy stratospheric O3 at high latitudes. Therefore, it is crucial to understand the importance of their production/loss rates, horizontal/vertical transport to advance our knowledge in the evolution of NOx and HOx as well as other related chemical species (e.g. HNO3, ClNO3, O and O3). Recently, we have developed a new coupled ion-neutral chemical model for the ionospheric D region (altitudes 50 - 90 km) based on the Sodankylä Ion and neutral Chemistry (SIC) model and 3D Whole Atmosphere Community Climate Model (WACCM), termed WACCM-SIC (Kovacs et al., 2016). An extra 306 ion-neutral and ion-recombination reactions of neutral species, positive and negative ions, and electrons have been added to the standard chemistry in WACCM. WACCM-SIC simulations have been performed to explore the relative contributions to mesospheric NO from auroral and medium energetic electrons, during the period 2013-2015. The modelled simulations are also compared with the available satellite measurements (e.g., temperature, O, H, and O3 from SABER, and NO from AIM) and ground-based microwave radiometer observations of mesospheric NO at Halley station (75oS). The interannual and inter-hemisphere differences will also be discussed.

  19. The effect of horizontal resolution of the simulation of precipitation extremes in the Community Atmospheric model version 5.1

    NASA Astrophysics Data System (ADS)

    Wehner, M. F.; Prabhat, M.; Li, F.; Paciorek, C. J.; Collins, W.

    2014-12-01

    Contemporary high performance computing technology currently enables multi-decadal global atmospheric models at horizontal resolutions of 25km. Simulated storms in such models exhibit sharper gradients and higher extreme precipitations rates than is typical in CMIP5 class models. We compare daily and pentad extreme precipitation statistics from the Community Atmospheric model version 5.1 (CAM5.1) at resolutions of approximately 200, 100 and 25km at the equator with available gridded observational products. We find that there is considerable observational uncertainty in these products, but that the high-resolution configuration performs better than low-resolution configurations when cumulus processes do not contribute significantly to precipitation rates. However, we also find no evidence that simulated extreme precipitation rates have converged at the 25km resolution.

  20. Modeling land-surface processes and land-atmosphere interactions in the community weather and regional climate WRF model (Invited)

    NASA Astrophysics Data System (ADS)

    Chen, F.; Barlage, M. J.

    2013-12-01

    The Weather Research and Forecasting (WRF) model has been widely used with high-resolution configuration in the weather and regional climate communities, and hence demands its land-surface models to treat not only fast-response processes, such as plant evapotranspiration that are important for numerical weather prediction but also slow-evolving processes such as snow hydrology and interactions between surface soil water and deep aquifer. Correctly representing urbanization, which has been traditionally ignored in coarse-resolution modeling, is critical for applying WRF to air quality and public health research. To meet these demands, numerous efforts have been undertaken to improve land-surface models (LSM) in WRF, including the recent implementation of the Noah-MP (Noah Multiple-Physics). Noah-MP uses multiple options for key sub-grid land-atmosphere interaction processes (Niu et al., 2011; Yang et al., 2011), and contains a separate vegetation canopy representing within- and under-canopy radiation and turbulent processes, a multilayer physically-based snow model, and a photosynthesis canopy resistance parameterization with a dynamic vegetation model. This paper will focus on the interactions between fast and slow land processes through: 1) a benchmarking of the Noah-MP performance, in comparison to five widely-used land-surface models, in simulating and diagnosing snow evolution for complex terrain forested regions, and 2) the effects of interactions between shallow and deep aquifers on regional weather and climate. Moreover, we will provide an overview of recent improvements of the integrated WRF-Urban modeling system, especially its hydrological enhancements that takes into account the effects of lawn irrigation, urban oasis, evaporation from pavements, anthropogenic moisture sources, and a green-roof parameterization.

  1. The Madden-Julian Oscillation in the National Center for Atmospheric Research Community Atmospheric Model-2 with the Tiedtke Convective Scheme

    SciTech Connect

    Liu, P; Wang, B; Sperber, K R; Li, T; Meehl, G A

    2004-07-26

    The boreal winter Madden-Julian oscillation (MJO) remains very weak and irregular in structure in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model version 2 (CAM2) as in its direct predecessor, the Community Climate Model version 3 (CCM3). The standard version of CAM2 uses the deep convective scheme of Zhang and McFarlane (1995), as in CCM3, with the closure dependent on convective available potential energy (CAPE). Here, sensitivity tests using several versions of the Tiedtke (1989) convective scheme are conducted. Typically, the Tiedtke convection scheme gives an improved mean state, intraseasonal variability, space-time power spectra, and eastward propagation compared to the standard version of the model. Coherent eastward propagation of MJO related precipitation is also much improved, particularly over the Indian-western Pacific Oceans. Sensitivity experiments show that enhanced downdrafts in the Tiedtke scheme reduces the amplitude of the MJO but to a lesser extent than when this scheme is closed on CAPE to represent deep convections. A composite life cycle of the model MJO indicates that over the Indian Ocean wind induced surface heat exchange functions, while over the western/central Pacific Ocean aspects of frictional moisture convergence are evident in the maintenance and eastward propagation of the oscillation.

  2. Atmospheric Modeling

    EPA Science Inventory

    Although air quality models have been applied historically to address issues specific to ambient air quality standards (i.e., one criteria pollutant at a time) or welfare (e.g.. acid deposition or visibility impairment). they are inherently multipollutant based. Therefore. in pri...

  3. Atmospheric Modeling

    EPA Science Inventory

    Although air quality models have been applied historically to address issues specific to ambient air quality standards (i.e., one criteria pollutant at a time) or welfare (e.g.. acid deposition or visibility impairment). they are inherently multipollutant based. Therefore. in pri...

  4. Midlatitude atmospheric responses to Arctic sensible heat flux anomalies in Community Climate Model, Version 4

    NASA Astrophysics Data System (ADS)

    Mills, Catrin M.; Cassano, John J.; Cassano, Elizabeth N.

    2016-12-01

    Possible linkages between Arctic sea ice loss and midlatitude weather are strongly debated in the literature. We analyze a coupled model simulation to assess the possibility of Arctic ice variability forcing a midlatitude response, ensuring consistency between atmosphere, ocean, and ice components. We work with weekly running mean daily sensible heat fluxes with the self-organizing map technique to identify Arctic sensible heat flux anomaly patterns and the associated atmospheric response, without the need of metrics to define the Arctic forcing or measure the midlatitude response. We find that low-level warm anomalies during autumn can build planetary wave patterns that propagate downstream into the midlatitudes, creating robust surface cold anomalies in the eastern United States.

  5. Moisture and temperature balances at the Atmospheric Radiation Measurement Southern Great Plains Site in forecasts with the Community Atmosphere Model (CAM2)

    NASA Astrophysics Data System (ADS)

    Williamson, D. L.; Boyle, J.; Cederwall, R.; Fiorino, M.; Hnilo, J.; Olson, J.; Phillips, T.; Potter, G.; Xie, S. C.

    2005-08-01

    We compare the balance of terms in moisture and temperature prediction equations during short forecasts by the Community Atmosphere Model (CAM2) with observed estimates at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site for two intensive observing periods (IOPs). The goal is to provide insight into parameterization errors which ultimately should lead to model improvements. The atmospheric initial conditions are obtained from high-resolution numerical weather prediction (NWP) analyses. The land initial conditions are spun up to be consistent with those analyses. Three cases are considered: (1) June/July 1997 when the atmosphere is relatively moist and surface evaporation corresponds to 90% of the precipitation with advection accounting for the remainder; (2) rainy days in April 1997 when the atmosphere is less moist and horizontal advection accounts for much of the precipitation with a small contribution from surface evaporation and the balance being derived from the water already present in the column; and (3) nonrainy days of the April 1997 when the moist process parameterizations are inactive and the planetary boundary layer (PBL) parameterization is dominant. For the first case the Zhang-McFarlane deep convective parameterization drives the model to a wrong state. For the second the Hack shallow convective parameterization appears to be not acting deep enough. During both periods inconsistencies between CAM2 and ARM surface fluxes, land surface conditions and the net surface radiative fluxes indicate that the exchange parameterizations should be examined further. For the third case the PBL parameterization does not appear to create the correct vertical structure. In addition, the individual components of the dynamical tendency are very different between CAM2 and ARM, although the total dynamical tendency is similar in the two. Although these observations do not imply that those components are themselves wrong since they may be responding

  6. Sensitivities of the hydrologic cycle to model physics, grid resolution, and ocean type in the aquaplanet Community Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Benedict, James J.; Medeiros, Brian; Clement, Amy C.; Pendergrass, Angeline G.

    2017-06-01

    Precipitation distributions and extremes play a fundamental role in shaping Earth's climate and yet are poorly represented in many global climate models. Here, a suite of idealized Community Atmosphere Model (CAM) aquaplanet simulations is examined to assess the aquaplanet's ability to reproduce hydroclimate statistics of real-Earth configurations and to investigate sensitivities of precipitation distributions and extremes to model physics, horizontal grid resolution, and ocean type. Little difference in precipitation statistics is found between aquaplanets using time-constant sea-surface temperatures and those implementing a slab ocean model with a 50 m mixed-layer depth. In contrast, CAM version 5.3 (CAM5.3) produces more time mean, zonally averaged precipitation than CAM version 4 (CAM4), while CAM4 generates significantly larger precipitation variance and frequencies of extremely intense precipitation events. The largest model configuration-based precipitation sensitivities relate to choice of horizontal grid resolution in the selected range 1-2°. Refining grid resolution has significant physics-dependent effects on tropical precipitation: for CAM4, time mean zonal mean precipitation increases along the Equator and the intertropical convergence zone (ITCZ) narrows, while for CAM5.3 precipitation decreases along the Equator and the twin branches of the ITCZ shift poleward. Increased grid resolution also reduces light precipitation frequencies and enhances extreme precipitation for both CAM4 and CAM5.3 resulting in better alignment with observational estimates. A discussion of the potential implications these hydrologic cycle sensitivities have on the interpretation of precipitation statistics in future climate projections is also presented.Plain Language SummaryPrecipitation plays a fundamental role in shaping Earth's climate. Global climate <span class="hlt">models</span> predict the average precipitation reasonably well but often struggle</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1213425','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1213425"><span>The effect of horizontal resolution on simulation quality in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span>, CAM5.1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wehner, Michael F.; Reed, Kevin A.; Li, Fuyu; Prabhat, -; Bacmeister, Julio; Chen, Cheng -Ta; Paciorek, Christopher; Gleckler, Peter J.; Sperber, Kenneth R.; Collins, William D.; Gettelman, Andrew; Jablonowski, Christiane</p> <p>2014-11-05</p> <p>We present an analysis of version 5.1 of the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM5.1) at a high horizontal resolution. Intercomparison of this global <span class="hlt">model</span> at approximately 0.25°, 1°, and 2° is presented for extreme daily precipitation as well as for a suite of seasonal mean fields. In general, extreme precipitation amounts are larger in high resolution than in lower-resolution configurations. In many but not all locations and/or seasons, extreme daily precipitation rates in the high-resolution configuration are higher and more realistic. The high-resolution configuration produces tropical cyclones up to category 5 on the Saffir-Simpson scale and a comparison to observations reveals both realistic and unrealistic <span class="hlt">model</span> behavior. In the absence of extensive <span class="hlt">model</span> tuning at high resolution, simulation of many of the mean fields analyzed in this study is degraded compared to the tuned lower-resolution public released version of the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy...47.2747T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy...47.2747T"><span>Diagnosing the possible dynamics controlling Sahel precipitation in the short-range ensemble <span class="hlt">community</span> <span class="hlt">atmospheric</span> <span class="hlt">model</span> hindcasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tseng, Yu-heng; Lin, Yen-heng; Lo, Min-hui; Yang, Shu-chih</p> <p>2016-11-01</p> <p>The actual dynamics and physical mechanisms affecting the Sahel precipitation pattern and amplitude in the climate <span class="hlt">models</span> remain under debate due to the inconsistent drying and rainfall variability/pattern among them. We diagnose the boreal summer rainfall pattern in the Sahel and its possible causes using short-range ensemble hindcasts based on NCAR <span class="hlt">community</span> <span class="hlt">atmospheric</span> <span class="hlt">model</span> with the local ensemble transform Kalman filter (CAM-LETKF) data assimilation. The CAM-LETKF assimilation was conducted using 64 ensemble members with an assimilation cycle of 6-h. By comparing the superior and inferior groups within these 64 ensembles, we confirmed the influence of the Atlantic in the West Sahel rainfall (a robust feature in the ensembles) and a severe <span class="hlt">model</span> bias resulting from erroneously <span class="hlt">modeled</span> locations and magnitudes of low-level Sahara heat low (SHL) and African easterly jet (AEJ). This bias is highly related to <span class="hlt">atmospheric</span> jet dynamics as shown in recent studies and local wave instability triggered mainly by the boundary-layer temperature gradient and amplified by land-<span class="hlt">atmosphere</span> interactions. In particular, our results demonstrated that more accurate divergence and convergence fields resulting from improved SHL and AEJ in the superior groups enabled more accurate rainbelt patterns to be discerned, thus improving the ensemble mean <span class="hlt">model</span> hindcast prediction by more than 25 % in precipitation and 16 % in temperature. We concluded that the use of low-resolution climate <span class="hlt">models</span> to project future rainfall in the Sahel requires caution because the <span class="hlt">model</span> hindcasts may quickly diverge even the same boundary conditions and forcings are applied. The <span class="hlt">model</span> bias may easily grow up within a few months in the short-range CAM-LETKF hindcast, let along the free <span class="hlt">model</span> centennial simulations. Unconstrained future climate <span class="hlt">model</span> projections for the Sahel must more effectively capture the short-term key boundary-layer dynamics in the boreal summer to be credible regardless <span class="hlt">model</span> dynamics</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16825468','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16825468"><span>Effects of elevated <span class="hlt">atmospheric</span> carbon dioxide on biomass and carbon accumulation in a <span class="hlt">model</span> regenerating longleaf pine <span class="hlt">community</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Runion, G B; Davis, M A; Pritchard, S G; Prior, S A; Mitchell, R J; Torbert, H A; Rogers, H H; Dute, R R</p> <p>2006-01-01</p> <p>Plant species vary in response to <span class="hlt">atmospheric</span> CO2 concentration due to differences in physiology, morphology, phenology, and symbiotic relationships. These differences make it very difficult to predict how plant <span class="hlt">communities</span> will respond to elevated CO2. Such information is critical to furthering our understanding of <span class="hlt">community</span> and ecosystem responses to global climate change. To determine how a simple plant <span class="hlt">community</span> might respond to elevated CO2, a <span class="hlt">model</span> regenerating longleaf pine <span class="hlt">community</span> composed of five species was exposed to two CO2 regimes (ambient, 365 micromol mol(-1) and elevated, 720 micromol mol(-1)) for 3 yr. Total above- and belowground biomass was 70 and 49% greater, respectively, in CO2-enriched plots. Carbon (C) content followed a response pattern similar to biomass, resulting in a significant increase of 13.8 Mg C ha(-1) under elevated CO2. Responses of individual species, however, varied. Longleaf pine (Pinus palustris Mill.) was primarily responsible for the positive response to CO2 enrichment. Wiregrass (Aristida stricta Michx.), rattlebox (Crotalaria rotundifolia Walt. Ex Gmel.), and butterfly weed (Asclepias tuberosa L.) exhibited negative above- and belowground biomass responses to elevated CO2, while sand post oak (Quercus margaretta Ashe) did not differ significantly between CO2 treatments. As with pine, C content followed patterns similar to biomass. Elevated CO2 resulted in alterations in <span class="hlt">community</span> structure. Longleaf pine comprised 88% of total biomass in CO2-enriched plots, but only 76% in ambient plots. In contrast, wiregrass, rattlebox, and butterfly weed comprised 19% in ambient CO2 plots, but only 8% under high CO2. Therefore, while longleaf pine may perform well in a high CO2 world, other members of this <span class="hlt">community</span> may not compete as well, which could alter <span class="hlt">community</span> function. Effects of elevated CO2 on plant <span class="hlt">communities</span> are complex, dynamic, and difficult to predict, clearly demonstrating the need for more research in this</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1334768','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1334768"><span>Using ARM Measurements to Understand and Reduce the Double ITCZ Biases in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhang, Minghua</p> <p>2016-12-08</p> <p>1. Understanding of the observed variability of ITCZ in the equatorial eastern Pacific. The annual mean precipitation in the eastern Pacific has a maximum zonal band north of the equator in the ITCZ where the maximum SST is located. During the boreal spring (referring to February, March, and April throughout the present paper), because of the accumulated solar radiation heating and oceanic heat transport, a secondary maximum of SST exists in the southeastern equatorial Pacific. Associated with this warm SST is also a seasonal transitional maximum of precipitation in the same region in boreal spring, exhibited as a weak double ITCZ pattern in the equatorial eastern Pacific. This climatological seasonal variation, however, varies greatly from year to year: double ITCZ in the boreal spring occurs in some years but not in other years; when there a single ITCZ, it can appear either north, south or at the equator. Understanding this observed variability is critical to find the ultimate cause of the double ITCZ in climate <span class="hlt">models</span>. Seasonal variation of ITCZ south of the eastern equatorial Pacific: By analyzing data from satellites, field measurements and <span class="hlt">atmospheric</span> reanalysis, we have found that in the region where spurious ITCZ in <span class="hlt">models</span> occurs, there is a “seasonal cloud transition” — from stratocumulus to shallow cumulus and eventually to deep convection —in the South Equatorial Pacific (SEP) from September to April that is similar to the spatial cloud transition from the California coast to the equator. This seasonal transition is associated with increasing sea surface temperature (SST), decreasing lower tropospheric stability and large-scale subsidence. This finding of seasonal cloud transition points to the same source of <span class="hlt">model</span> errors in the ITCZ simulations as in simulation of stratocumulus-cumulus-deep convection transition. It provides a test for climate <span class="hlt">models</span> to simulate the relationships between clouds and large-scale <span class="hlt">atmospheric</span> fields in a region</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMIN21A1206D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMIN21A1206D"><span><span class="hlt">Community</span> Access to <span class="hlt">Atmospheric</span> Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Durbin, P. B.; Tilmes, C. A.; Parris, F. E.; Martin, A. T.; Soika, V.; Bichali, L.; Higgins, P. H.</p> <p>2006-12-01</p> <p>This paper provides an overview of the computer application that provides <span class="hlt">community</span> access to <span class="hlt">atmosphere</span> measurements derived from backscatter ultraviolet sources. It is funded by NASA's Advance Collaborative Connections for Earth-Sun System Science (ACCESS), and is devoted to Measurements of <span class="hlt">Atmospheric</span> Chemistry in the Ultraviolet (MACUV). The purpose is to provide "one-stop shopping" for data and information of interest to the Backscattered Ultraviolet (BUV) <span class="hlt">community</span>. It is built from the well-used, highly successful Total Ozone Mapping Spectrometer (TOMS) website and is being evolved into a broader focus for the BUV <span class="hlt">community</span>. This application supports NASA's evolutionary step toward science measurement processing and analysis systems and enables the BUV <span class="hlt">community</span> to easily access information and expertise from multiple sources over a nearly 30 year history of space based remote sensing of the <span class="hlt">atmosphere</span>. It facilitates finding and comparing data, algorithms, and scientific results from different parts of the BUV science <span class="hlt">community</span> as well as from different instruments and missions. It provides the means to manage and access the products of the Ozone <span class="hlt">Community</span> Oriented Measurement-based Processing System (ComPS). The MACUV application contains components that store and manage data, manage user access to that data, provide multi-dimensional views of the data and other information, serve data based on user criteria, and facilitate on-line collaboration. The web site hosts Algorithm Theoretical Basis documents for each data product, quality assessment of those products, published papers, instrument descriptions, access to mission information, reports and assessments of events and issues, problem reporting and tracking, a moderated forum, and a user collaboration area. Visitors to the MACUV web site fall into several categories: the general public; students, educators and researchers outside the BUV <span class="hlt">community</span>; members of the BUV <span class="hlt">community</span> who validate the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMIN33A..15M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMIN33A..15M"><span><span class="hlt">Community</span> Access to <span class="hlt">Atmospheric</span> Measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marshall, J. J.; Batluck, G. R.; Durbin, P. B.; Gerard, R.; Larko, D. E.; Martin, A.; Tilmes, C. A.</p> <p>2007-05-01</p> <p>This poster provides an overview of the computer system that provides <span class="hlt">community</span> access to <span class="hlt">atmosphere</span> measurements derived from backscatter ultraviolet sources. It is funded by NASA's Advancing Collaborative Connections for Earth-Sun System Science (ACCESS), and is devoted to Measurements of <span class="hlt">Atmospheric</span> Composition in the Ultraviolet. The purpose is to provide "one-stop shopping" for data and information of interested to the Backscattered Ultraviolet (BUV) <span class="hlt">community</span>. It is built from the well-used, highly successful Total Ozone Mapping Spectrometer (TOMS) web site, and is being evolved into a broader focus for the BUV <span class="hlt">community</span>. This effort supports NASA's evolutionary step toward science measurement processing and analysis systems, and enables the BUV <span class="hlt">community</span> to easily access information and expertise from multiple sources over a nearly 30 year history of space-based remote sensing of the <span class="hlt">atmosphere</span>. It facilitates finding algorithms and scientific results from different parts of the BUV science <span class="hlt">community</span> as well as from different instruments and missions. It provides the means to access the products of the Ozone <span class="hlt">Community</span> Oriented Measurement-based Processing System (ComPS). The system contains components that store and manage data, manage user access to that data, provide multi-dimensional views of the data and other information, serve data based on user criteria, and facilitate on-line collaboration. The web site hosts Algorithm Theoretical Basis documents, quality assessment of data products, published papers, instrument descriptions, access to mission information, reports and assessments of events and issues, problem reporting and tracking, a moderated forum, and a user collaboration area. Visitors to the web site fall into several categories: the general public; students, educators, and researchers outside the BUV <span class="hlt">community</span>; members of the BUV <span class="hlt">community</span> who validate the measurements; members of the <span class="hlt">community</span> who develop algorithms and software. Access to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1040956','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1040956"><span>Toward a Minimal Representation of Aerosols in Climate <span class="hlt">Models</span>: Description and Evaluation in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, Xiaohong; Easter, Richard C.; Ghan, Steven J.; Zaveri, Rahul A.; Rasch, Philip J.; Shi, Xiangjun; Lamarque, J.-F.; Gettelman, A.; Morrison, H.; Vitt, Francis; Conley, Andrew; Park, S.; Neale, Richard; Hannay, Cecile; Ekman, A. M.; Hess, Peter; Mahowald, N.; Collins, William D.; Iacono, Michael J.; Bretherton, Christopher S.; Flanner, M. G.; Mitchell, David</p> <p>2012-05-21</p> <p>A modal aerosol module (MAM) has been developed for the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5), the <span class="hlt">atmospheric</span> component of the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> version 1 (CESM1). MAM is capable of simulating the aerosol size distribution and both internal and external mixing between aerosol components, treating numerous complicated aerosol processes and aerosol physical, chemical and optical properties in a physically based manner. Two MAM versions were developed: a more complete version with seven-lognormal modes (MAM7), and a three-lognormal mode version (MAM3) for the purpose of long-term (decades to centuries) simulations. Major approximations in MAM3 include assuming immediate mixing of primary organic matter (POM) and black carbon (BC) with other aerosol components, merging of the MAM7 fine dust and fine sea salt modes into the accumulation mode, merging of the MAM7 coarse dust and coarse sea salt modes into the single coarse mode, and neglecting the explicit treatment of ammonia and ammonium cycles. Simulated sulfate and secondary organic aerosol (SOA) mass concentrations are remarkably similar between MAM3 and MAM7 as most ({approx}90%) of these aerosol species are in the accumulation mode. Differences of POM and BC concentrations between MAM3 and MAM7 are also small (mostly within 10%) because of the assumed hygroscopic nature of POM, so that freshly emitted POM and BC are wet-removed before mixing internally with soluble aerosol species. Sensitivity tests with the POM assumed to be hydrophobic and with slower aging process increase the POM and BC concentrations, especially at high latitudes (by several times). The mineral dust global burden differs by 10% and sea salt burden by 30-40% between MAM3 and MAM7 mainly due to the different size ranges for dust and sea salt modes and different standard deviations of log-normal size distribution for sea salt modes between MAM3 and MAM7. The <span class="hlt">model</span> is able to qualitatively capture the observed geographical and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A43C0298B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A43C0298B"><span>How much does sea spray aerosol organic matter impact clouds and radiation? Sensitivity studies in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burrows, S. M.; Liu, X.; Elliott, S.; Easter, R. C.; Singh, B.; Rasch, P. J.</p> <p>2015-12-01</p> <p>Submicron marine aerosol particles are frequently observed to contain substantial fractions of organic material, hypothesized to enter the <span class="hlt">atmosphere</span> as part of the primary sea spray aerosol formed through bubble bursting. This organic matter in sea spray aerosol may affect cloud condensation nuclei and ice nuclei concentrations in the <span class="hlt">atmosphere</span>, particularly in remote marine regions. Members of our team have developed a new, mechanistic representation of the enrichment of sea spray aerosol with organic matter, the OCEANFILMS parameterization (Burrows et al., 2014). This new representation uses fields from an ocean biogeochemistry <span class="hlt">model</span> to predict properties of the emitted aerosol. We have recently implemented the OCEANFILMS representation of sea spray aerosol composition into the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM), and performed sensitivity experiments and comparisons with alternate formulations. Early results from these sensitivity simulations will be shown, including impacts on aerosols, clouds, and radiation. References: Burrows, S. M., Ogunro, O., Frossard, A. A., Russell, L. M., Rasch, P. J., and Elliott, S. M.: A physically based framework for <span class="hlt">modeling</span> the organic fractionation of sea spray aerosol from bubble film Langmuir equilibria, Atmos. Chem. Phys., 14, 13601-13629, doi:10.5194/acp-14-13601-2014, 2014.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=63744&keyword=Thermodynamics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=63744&keyword=Thermodynamics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>ONE-<span class="hlt">ATMOSPHERE</span> DYNAMICS DESCRIPTION IN THE <span class="hlt">MODELS</span>-3 <span class="hlt">COMMUNITY</span> MULTI-SCALE QUALITY (CMAQ) <span class="hlt">MODELING</span> SYSTEM</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This paper proposes a general procedure to link meteorological data with air quality <span class="hlt">models</span>, such as U.S. EPA's <span class="hlt">Models</span>-3 <span class="hlt">Community</span> Multi-scale Air Quality (CMAQ) <span class="hlt">modeling</span> system. CMAQ is intended to be used for studying multi-scale (urban and regional) and multi-pollutant (ozon...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=63744&keyword=Thermodynamics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91040738&CFTOKEN=55703293','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=63744&keyword=Thermodynamics&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91040738&CFTOKEN=55703293"><span>ONE-<span class="hlt">ATMOSPHERE</span> DYNAMICS DESCRIPTION IN THE <span class="hlt">MODELS</span>-3 <span class="hlt">COMMUNITY</span> MULTI-SCALE QUALITY (CMAQ) <span class="hlt">MODELING</span> SYSTEM</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This paper proposes a general procedure to link meteorological data with air quality <span class="hlt">models</span>, such as U.S. EPA's <span class="hlt">Models</span>-3 <span class="hlt">Community</span> Multi-scale Air Quality (CMAQ) <span class="hlt">modeling</span> system. CMAQ is intended to be used for studying multi-scale (urban and regional) and multi-pollutant (ozon...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A33G0268B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A33G0268B"><span>Using A-Train Observations to Evaluate Ice Water Path and Ice Cloud Radiative Effects in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berry, B. J.</p> <p>2015-12-01</p> <p>In this study we first use A-Train satellite data to investigate the distribution of clouds, along with their radiative and microphysical properties, in Southeast Asia during the summer monsoon. The distribution of ice water path (IWP) in this region is highly skewed, such that the mean value is not representative of the typical ice cloud. In examining how cirrus cloud radiative effects at the TOA vary as a function of IWP, we find that cirrus with an IWP less than 200 g m-2 produce a net warming. And weighting the radiative effect by the frequency of occurrence of IWP, reveals that cirrus with an IWP around 20 g m-2contribute most to the heating at the TOA. Next, we use the A-Train results to address the issues of IWP occurrence and high cloud forcing in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5. Our goal is to determine if the clouds that heat the upper troposphere in the <span class="hlt">model</span> are the same genre of clouds that heat the upper troposphere in the real <span class="hlt">atmosphere</span>. First, we assess the distribution of ice cloud fraction in the <span class="hlt">model</span>. Then we define a cloud radiative kernel that's a function of cloud top pressure and IWP, to determine whether the <span class="hlt">modeled</span> ice clouds produce similar shortwave and longwave radiative effects at the TOA. Lastly, we use the cloud radiative kernel and cloud fraction histogram to evaluate how the ice cloud forcing in the <span class="hlt">model</span> compares to the ice cloud forcing derived from A-Train.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15013643','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15013643"><span>EVALUATION OF AN IMPROVED CONVECTION TRIGGERING MECHANISM IN THE NCAR <span class="hlt">COMMUNITY</span> <span class="hlt">ATMOSPHERE</span> <span class="hlt">MODEL</span> CAM2 UNDER CAPT FRAMEWORK</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Xie, S; Boyle, J S; Cederwall, R T; Potter, G L; Zhang, M</p> <p>2003-10-15</p> <p>The problem that convection over land is overactive during warm-season daytime in the National Center for <span class="hlt">Atmospheric</span> Research (NCAR) <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM2 and its previous version (CCM3) has been found both in its single-column <span class="hlt">model</span> (SCM) simulations (Xie and Zhang 2000; Ghan et al. 2000; Xie et al. 2002) and in its full general circulation <span class="hlt">model</span> (GCM) short-range weather forecasts (Phillips et al. 2003) and climate simulations (Dai and Trenberth 2003). These studies showed that this problem is closely related to the convection triggering mechanism used in its deep convection scheme (Zhang and McFarlane 1995), which assumes that convection is triggered whenever there is positive convective available potential energy (CAPE). The positive CAPE triggering mechanism initiates <span class="hlt">model</span> convection too often during the day because of the strong diurnal variations in the surface isolation and the induced CAPE diurnal change over land in the warm season. To reduce the problem, Xie and Zhang (2000) introduced a dynamic constraint, i.e., a dynamic CAPE generation rate (DCAPE) determined by the large-scale advective tendencies of temperature and moisture, to control the onset of deep convection. They showed that positive DCAPE is closely associated with convection in observations and the dynamic constraint could largely reduce the effect of the strong diurnal variations in the surface fluxes on the initiation of convection. Using the SCM version of CCM3, which has the same deep convection scheme as CAM2, Xie and Zhang (2000) showed that considerable improvements can be obtained in the <span class="hlt">model</span> simulation of precipitation and other thermodynamic fields when the dynamic constraint was applied to the <span class="hlt">model</span> triggering function. However, the performance of the improved convection triggering mechanism in the full GCM has not been tested. In this study, we will test the improved convection trigger mechanism in CAM2 under the U.S. Department of Energy's Climate Change Prediction</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC41F0649L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC41F0649L"><span>The Social Network of Tracer Variations and O(100) Uncertain Photochemical Parameters in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lucas, D. D.; Labute, M.; Chowdhary, K.; Debusschere, B.; Cameron-Smith, P. J.</p> <p>2014-12-01</p> <p>Simulating the <span class="hlt">atmospheric</span> cycles of ozone, methane, and other radiatively important trace gases in global climate <span class="hlt">models</span> is computationally demanding and requires the use of 100's of photochemical parameters with uncertain values. Quantitative analysis of the effects of these uncertainties on tracer distributions, radiative forcing, and other <span class="hlt">model</span> responses is hindered by the "curse of dimensionality." We describe efforts to overcome this curse using ensemble simulations and advanced statistical methods. Uncertainties from 95 photochemical parameters in the trop-MOZART scheme were sampled using a Monte Carlo method and propagated through 10,000 simulations of the single column version of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM). The variance of the ensemble was represented as a network with nodes and edges, and the topology and connections in the network were analyzed using lasso regression, Bayesian compressive sensing, and centrality measures from the field of social network theory. Despite the limited sample size for this high dimensional problem, our methods determined the key sources of variation and co-variation in the ensemble and identified important clusters in the network topology. Our results can be used to better understand the flow of photochemical uncertainty in simulations using CAM and other climate <span class="hlt">models</span>. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and supported by the DOE Office of Science through the Scientific Discovery Through Advanced Computing (SciDAC).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/990526','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/990526"><span>Global Simulations of Ice nucleation and Ice Supersaturation with an Improved Cloud Scheme in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gettelman, A.; Liu, Xiaohong; Ghan, Steven J.; Morrison, H.; Park, Sungsu; Conley, Andrew; Klein, Stephen A.; Boyle, James; Mitchell, David; Li, J-L F.</p> <p>2010-09-28</p> <p>A process-based treatment of ice supersaturation and ice-nucleation is implemented in the National Center for <span class="hlt">Atmospheric</span> Research (NCAR) <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM). The new scheme is designed to allow (1) supersaturation with respect to ice, (2) ice nucleation by aerosol particles and (3) ice cloud cover consistent with ice microphysics. The scheme is implemented with a 4-class 2 moment microphysics code and is used to evaluate ice cloud nucleation mechanisms and supersaturation in CAM. The new <span class="hlt">model</span> is able to reproduce field observations of ice mass and mixed phase cloud occurrence better than previous versions of the <span class="hlt">model</span>. Simulations indicate heterogeneous freezing and contact nucleation on dust are both potentially important over remote areas of the Arctic. Cloud forcing and hence climate is sensitive to different formulations of the ice microphysics. Arctic radiative fluxes are sensitive to the parameterization of ice clouds. These results indicate that ice clouds are potentially an important part of understanding cloud forcing and potential cloud feedbacks, particularly in the Arctic.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24448482','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24448482"><span><span class="hlt">Modeled</span> subalpine plant <span class="hlt">community</span> response to climate change and <span class="hlt">atmospheric</span> nitrogen deposition in Rocky Mountain National Park, USA.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McDonnell, T C; Belyazid, S; Sullivan, T J; Sverdrup, H; Bowman, W D; Porter, E M</p> <p>2014-04-01</p> <p>To evaluate potential long-term effects of climate change and <span class="hlt">atmospheric</span> nitrogen (N) deposition on subalpine ecosystems, the coupled biogeochemical and vegetation <span class="hlt">community</span> competition <span class="hlt">model</span> ForSAFE-Veg was applied to a site at the Loch Vale watershed of Rocky Mountain National Park, Colorado. Changes in climate and N deposition since 1900 resulted in pronounced changes in simulated plant species cover as compared with ambient and estimated future <span class="hlt">community</span> composition. The estimated critical load (CL) of N deposition to protect against an average future (2010-2100) change in biodiversity of 10% was between 1.9 and 3.5 kg N ha(-1) yr(-1). Results suggest that the CL has been exceeded and vegetation at the study site has already undergone a change of more than 10% as a result of N deposition. Future increases in air temperature are forecast to cause further changes in plant <span class="hlt">community</span> composition, exacerbating changes in response to N deposition alone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JAMES...9.1399P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JAMES...9.1399P"><span>Impact of detrained cumulus on climate simulated by the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Version 5 with a unified convection scheme</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, Sungsu; Baek, Eun-Hyuk; Kim, Baek-Min; Kim, Seong-Joong</p> <p>2017-06-01</p> <p>Cumulus elements generated by detraining convective condensate-detrained cumulus-are added to the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Version 5 (CAM5) combined with a Unified Convection Scheme (UNICON). Instead of evaporating convective liquids detrained into clear portions, we diagnosed a new detrained cumulus that is horizontally nonoverlapped with cumulus and stratus in each layer by assuming a steady state balance between the detrainment rate of cumulus condensates and the dissipation rate of detrained condensates by entrainment mixing with environmental air. The addition of detrained cumulus was found to substantially improve the simulation of low-level clouds and the associated shortwave cloud radiative forcing, particularly in the subtropical trade cumulus regime. In addition to the mean climate, successful simulations of the diurnal cycle of precipitation, Madden-Julian Oscillation, and Kelvin wave were also well maintained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A53G3297P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A53G3297P"><span>Surprising Resilience of the Madden-Julian Oscillation to Extreme Climate Cooling in the Superparameterized <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pritchard, M. S.; Yang, D.</p> <p>2014-12-01</p> <p>We test the hypothesis that radiative convective equilibrium (RCE) self-aggregation is a good metaphor for the maintenance of the Madden-Julian Oscillation by imposing extreme cooling in the Superparameterized <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (SPCAM) v. 3.0 in a uniform SST configuration. The expectation is that - like RCE self-aggregation - SPCAM's simulated MJO should shut down at sea surface temperatures significantly less than 25 degrees Celsius. Remarkably, the MJO in SPCAM is resilient to extreme cooling down to one degree Celsius. With cooling, the simulated MJO becomes more barotropic and its zonal wavelength decreases. The amplitude decrease and horizontal scale contraction are consistent with the theoretical prediction from Yang and Ingersoll (2014, GRL).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780007684','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780007684"><span><span class="hlt">Atmospheric</span> density <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mueller, A. C.</p> <p>1977-01-01</p> <p>An <span class="hlt">atmospheric</span> <span class="hlt">model</span> developed by Jacchia, quite accurate but requiring a large amount of computer storage and execution time, was found to be ill-suited for the space shuttle onboard program. The development of a simple <span class="hlt">atmospheric</span> density <span class="hlt">model</span> to simulate the Jacchia <span class="hlt">model</span> was studied. Required characteristics including variation with solar activity, diurnal variation, variation with geomagnetic activity, semiannual variation, and variation with height were met by the new <span class="hlt">atmospheric</span> density <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1213425-effect-horizontal-resolution-simulation-quality-community-atmospheric-model-cam5','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1213425-effect-horizontal-resolution-simulation-quality-community-atmospheric-model-cam5"><span>The effect of horizontal resolution on simulation quality in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span>, CAM5.1</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Wehner, Michael F.; Reed, Kevin A.; Li, Fuyu; ...</p> <p>2014-11-05</p> <p>We present an analysis of version 5.1 of the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM5.1) at a high horizontal resolution. Intercomparison of this global <span class="hlt">model</span> at approximately 0.25°, 1°, and 2° is presented for extreme daily precipitation as well as for a suite of seasonal mean fields. In general, extreme precipitation amounts are larger in high resolution than in lower-resolution configurations. In many but not all locations and/or seasons, extreme daily precipitation rates in the high-resolution configuration are higher and more realistic. The high-resolution configuration produces tropical cyclones up to category 5 on the Saffir-Simpson scale and a comparison to observations revealsmore » both realistic and unrealistic <span class="hlt">model</span> behavior. In the absence of extensive <span class="hlt">model</span> tuning at high resolution, simulation of many of the mean fields analyzed in this study is degraded compared to the tuned lower-resolution public released version of the <span class="hlt">model</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1107489','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1107489"><span>A Sensitivity Study of Radiative Fluxes at the Top of <span class="hlt">Atmosphere</span> to Cloud-Microphysics and Aerosol Parameters in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhao, Chun; Liu, Xiaohong; Qian, Yun; Yoon, Jin-Ho; Hou, Zhangshuan; Lin, Guang; McFarlane, Sally A.; Wang, Hailong; Yang, Ben; Ma, Po-Lun; Yan, Huiping; Bao, Jie</p> <p>2013-11-08</p> <p>In this study, we investigated the sensitivity of net radiative fluxes (FNET) at the top of <span class="hlt">atmosphere</span> (TOA) to 16 selected uncertain parameters mainly related to the cloud microphysics and aerosol schemes in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5). We adopted a quasi-Monte Carlo (QMC) sampling approach to effectively explore the high dimensional parameter space. The output response variables (e.g., FNET) were simulated using CAM5 for each parameter set, and then evaluated using generalized linear <span class="hlt">model</span> analysis. In response to the perturbations of these 16 parameters, the CAM5-simulated global annual mean FNET ranges from -9.8 to 3.5 W m-2 compared to the CAM5-simulated FNET of 1.9 W m-2 with the default parameter values. Variance-based sensitivity analysis was conducted to show the relative contributions of individual parameter perturbation to the global FNET variance. The results indicate that the changes in the global mean FNET are dominated by those of cloud forcing (CF) within the parameter ranges being investigated. The size threshold parameter related to auto-conversion of cloud ice to snow is confirmed as one of the most influential parameters for FNET in the CAM5 simulation. The strong heterogeneous geographic distribution of FNET variation shows parameters have a clear localized effect over regions where they are acting. However, some parameters also have non-local impacts on FNET variance. Although external factors, such as perturbations of anthropogenic and natural emissions, largely affect FNET variations at the regional scale, their impact is weaker than that of <span class="hlt">model</span> internal parameters in terms of simulating global mean FNET in this study. The interactions among the 16 selected parameters contribute a relatively small portion of the total FNET variations over most regions of the globe. This study helps us better understand the CAM5 <span class="hlt">model</span> behavior associated with parameter uncertainties, which will aid the next step of reducing <span class="hlt">model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1331376','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1331376"><span>Evaluation of Simulated Marine Aerosol Production Using the WaveWatchIII Prognostic Wave <span class="hlt">Model</span> Coupled to the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> within the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Long, M. S.; Keene, William C.; Zhang, J.; Reichl, B.; Shi, Y.; Hara, T.; Reid, J. S.; Fox-Kemper, B.; Craig, A. P.; Erickson, D. J.; Ginis, I.; Webb, A.</p> <p>2016-11-08</p> <p>Primary marine aerosol (PMA) is emitted into the <span class="hlt">atmosphere</span> via breaking wind waves on the ocean surface. Most parameterizations of PMA emissions use 10-meter wind speed as a proxy for wave action. This investigation coupled the 3<sup>rd</sup> generation prognostic WAVEWATCH-III wind-wave <span class="hlt">model</span> within a coupled Earth system <span class="hlt">model</span> (ESM) to drive PMA production using wave energy dissipation rate – analogous to whitecapping – in place of 10-meter wind speed. The wind speed parameterization did not capture basin-scale variability in relations between wind and wave fields. Overall, the wave parameterization did not improve comparison between simulated versus measured AOD or Na<sup>+</sup>, thus highlighting large remaining uncertainties in <span class="hlt">model</span> physics. Results confirm the efficacy of prognostic wind-wave <span class="hlt">models</span> for air-sea exchange studies coupled with laboratory- and field-based characterizations of the primary physical drivers of PMA production. No discernible correlations were evident between simulated PMA fields and observed chlorophyll or sea surface temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011689','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011689"><span>Global <span class="hlt">Atmospheric</span> Aerosol <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hendricks, Johannes; Aquila, Valentina; Righi, Mattia</p> <p>2012-01-01</p> <p>Global aerosol <span class="hlt">models</span> are used to study the distribution and properties of <span class="hlt">atmospheric</span> aerosol particles as well as their effects on clouds, <span class="hlt">atmospheric</span> chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global <span class="hlt">atmospheric</span> aerosol <span class="hlt">modeling</span> and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA533977','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA533977"><span>Thermospheric/Ionospheric Extension of the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM-X)</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2008-09-30</p> <p>the three­ dimensional chemical transport <span class="hlt">Model</span> for Ozone and Related chemical Tracers ( MOZART ) [Brasseur et al., 1998], which solves 51 neutral...P. J. Rasch, J. F. Muller, C. Granier, and X. X. Tie, MOZART , a global chemical transport <span class="hlt">model</span> for ozone and related chemical tracers 1. <span class="hlt">Model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6769615','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6769615"><span>Nonisothermal Pluto <span class="hlt">atmosphere</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hubbard, W.B.; Yelle, R.V.; Lunine, J.I. )</p> <p>1990-03-01</p> <p>The present thermal profile calculation for a Pluto <span class="hlt">atmosphere</span> <span class="hlt">model</span> characterized by a high number fraction of CH4 molecules encompasses <span class="hlt">atmospheric</span> heating by solar UV flux absorption and conductive transport cooling to the surface of Pluto. The stellar occultation curve predicted for an <span class="hlt">atmosphere</span> of several-microbar surface pressures (which entail the existence of a substantial temperature gradient close to the surface) agrees with observations and implies that the normal and tangential optical depth of the <span class="hlt">atmosphere</span> is almost negligible. The minimum period for <span class="hlt">atmospheric</span> methane depletion is calculated to be 30 years. 29 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A33B0204H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A33B0204H"><span>Analysis of Time step sensitivity in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> using Single-Column and Global Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Habtezion, B. L.; Caldwell, P.</p> <p>2013-12-01</p> <p>Global simulations of the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM) are shown to be very sensitive to physics time step. When the time step is decreased from its default value of 30 min to 7.5 min, cloud fraction, liquid and ice water path increase greatly. To better understand the time-convergence properties of the <span class="hlt">model</span> and to identify sources of time-step sensitivity, we have conducted single column <span class="hlt">model</span> simulations for a variety of cloud regimes. The sites used for these study include summertime mid-latitude continental convection (ARM95, ARM97), convection over the tropical-ocean (GATEIII, TOGAII, and TWP-ICE), mid-latitude cirrus (SPARTICUS), shallow convection (RICO), subtropical stratocumulus (DYCOMS2 RF01), and multi-level Arctic clouds (MPACE-A). Simulations at a variety of time steps were analyzed to quantify the magnitude of time truncation error in the default <span class="hlt">model</span> and the time-step required to obtain a numerically accurate solution. The relation between single-column and global <span class="hlt">model</span> results are explored by extracting nearest-neighbor grid-columns from climatological GCM experiments run at a variety of physics time steps; single-column and global results are found to be generally similar. Time-step sensitivity is found to result from numerical implementation issues and improved methods for <span class="hlt">model</span> integration are discussed. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA573274','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA573274"><span>Thermospheric/Ionospheric Extension of the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2007-09-30</p> <p>WACCM3. The WACCM3 chemistry module is derived from the three-dimensional chemical transport <span class="hlt">Model</span> for Ozone and Related chemical Tracers ( MOZART ...Walters, P. J. Rasch, J. F. Muller, C. Granier, and X. X. Tie, MOZART , a global chemical transport <span class="hlt">model</span> for ozone and related chemical tracers 1</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1091992','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1091992"><span>The Mean Climate of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM4) in Forced SST and Fully Coupled Experiments</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Neale, Richard B.; Richter, Jadwiga; Park, Sungsu; Lauritzen, Peter H.; Vavrus, Stephen J.; Rasch, Philip J.; Zhang, Minghua</p> <p>2013-07-01</p> <p>The <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span>, version 4 (CAM4), was released as part of the <span class="hlt">Community</span> Climate System <span class="hlt">Model</span>, version 4 (CCSM4). The finite volume (FV) dynamical core is now the default because of its superior transport and conservation properties. Deep convection parameterization changes include a dilute plume calculation of convective available potential energy (CAPE) and the introduction of convective momentum transport (CMT). An additional cloud fraction calculation is now performed following macrophysical state updates to provide improved thermodynamic consistency. A freeze-drying modification is further made to the cloud fraction calculation in very dry environments (e.g., the Arctic), where cloud fraction and cloud water values were often inconsistent in CAM3. In CAM4 the FV dynamical core further degrades the excessive trade-wind simulation, but reduces zonal stress errors at higher latitudes. Plume dilution alleviates much of the midtropospheric tropical dry biases and reduces the persistent monsoon precipitation biases over the Arabian Peninsula and the southern Indian Ocean. CMT reduces much of the excessive trade-wind biases in eastern ocean basins. CAM4 shows a global reduction in cloud fraction compared to CAM3, primarily as a result of the freeze-drying and improved cloud fraction equilibrium modifications. Regional climate feature improvements include the propagation of stationary waves from the Pacific into midlatitudes and the seasonal frequency of Northern Hemisphere blocking events. A 1° versus 2° horizontal resolution of the FV dynamical core exhibits superior improvements in regional climate features of precipitation and surface stress. Finally, improvements in the fully coupled mean climate between CAM3 and CAM4 are also more substantial than in forced sea surface temperature (SST) simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1168894-sensitivity-analysis-cloud-properties-clubb-parameters-single-column-community-atmosphere-model-scam5','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1168894-sensitivity-analysis-cloud-properties-clubb-parameters-single-column-community-atmosphere-model-scam5"><span>A sensitivity analysis of cloud properties to CLUBB parameters in the single-column <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (SCAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Guo, Zhun; Wang, Minghuai; Qian, Yun; ...</p> <p>2014-08-13</p> <p>In this study, we investigate the sensitivity of simulated shallow cumulus and stratocumulus clouds to selected tunable parameters of Cloud Layers Unified by Binormals (CLUBB) in the single column version of <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (SCAM5). A quasi-Monte Carlo (QMC) sampling approach is adopted to effectively explore the high-dimensional parameter space and a generalized linear <span class="hlt">model</span> is adopted to study the responses of simulated cloud fields to tunable parameters. One stratocumulus and two shallow convection cases are configured at both coarse and fine vertical resolutions in this study.. Our results show that most of the variance in simulated cloudmore » fields can be explained by a small number of tunable parameters. The parameters related to Newtonian and buoyancy-damping terms of total water flux are found to be the most influential parameters for stratocumulus. For shallow cumulus, the most influential parameters are those related to skewness of vertical velocity, reflecting the strong coupling between cloud properties and dynamics in this regime. The influential parameters in the stratocumulus case are sensitive to the choice of the vertical resolution while little sensitivity is found for the shallow convection cases, as eddy mixing length (or dissipation time scale) plays a more important role and depends more strongly on the vertical resolution in stratocumulus than in shallow convections. The influential parameters remain almost unchanged when the number of tunable parameters increases from 16 to 35. This study improves understanding of the CLUBB behavior associated with parameter uncertainties.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1168894','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1168894"><span>A sensitivity analysis of cloud properties to CLUBB parameters in the single-column <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (SCAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Guo, Zhun; Wang, Minghuai; Qian, Yun; Larson, Vincent E.; Ghan, Steven; Ovchinnikov, Mikhail; Bogenschutz, Peter A.; Zhao, Chun; Lin, Guang; Zhou, Tianjun</p> <p>2014-08-13</p> <p>In this study, we investigate the sensitivity of simulated shallow cumulus and stratocumulus clouds to selected tunable parameters of Cloud Layers Unified by Binormals (CLUBB) in the single column version of <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (SCAM5). A quasi-Monte Carlo (QMC) sampling approach is adopted to effectively explore the high-dimensional parameter space and a generalized linear <span class="hlt">model</span> is adopted to study the responses of simulated cloud fields to tunable parameters. One stratocumulus and two shallow convection cases are configured at both coarse and fine vertical resolutions in this study.. Our results show that most of the variance in simulated cloud fields can be explained by a small number of tunable parameters. The parameters related to Newtonian and buoyancy-damping terms of total water flux are found to be the most influential parameters for stratocumulus. For shallow cumulus, the most influential parameters are those related to skewness of vertical velocity, reflecting the strong coupling between cloud properties and dynamics in this regime. The influential parameters in the stratocumulus case are sensitive to the choice of the vertical resolution while little sensitivity is found for the shallow convection cases, as eddy mixing length (or dissipation time scale) plays a more important role and depends more strongly on the vertical resolution in stratocumulus than in shallow convections. The influential parameters remain almost unchanged when the number of tunable parameters increases from 16 to 35. This study improves understanding of the CLUBB behavior associated with parameter uncertainties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSA51B2421V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSA51B2421V"><span>Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> With Lower Ionospheric Chemistry: Improved <span class="hlt">Modeling</span> of Nitric Acid and Active Chlorine During Energetic Particle Precipitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Verronen, P. T.; Andersson, M. E.; Marsh, D. R.; Kovacs, T.; Plane, J. M. C.; Päivärinta, S. M.</p> <p>2016-12-01</p> <p>Energetic particle precipitation (EPP) and ion chemistry affect the neutral composition of the polar middle <span class="hlt">atmosphere</span>. For example, production of odd nitrogen and odd hydrogen during EPP events can decrease ozone by tens of percent. However, the standard ion chemistry parameterizations used in <span class="hlt">atmospheric</span> <span class="hlt">models</span> neglect the effects on some important species, such as nitric acid. We present WACCM-D, a variant of the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span>, which includes a set of lower ionosphere (D-region) chemistry: 307 reactions of 20 positive ions and 21 negative ions. Compared to the Sodankylä Ion and Neutral Chemistry (SIC), a state-of-the-art 1-D <span class="hlt">model</span> of the D-region chemistry, WACCM-D represents the lower ionosphere well. Comparison of ion concentrations between the <span class="hlt">models</span> shows that the WACCM-D bias is typically within ±10% or less below 70 km. At 70-90 km, when strong altitude gradients in ionization rates and/or ion concentrations exist, the bias can be larger for some ions but is still within tens of percent. We also compare WACCM-D results for the January 2005 solar proton event (SPE) to those from the standard WACCM and observations from the Aura/MLS and SCISAT/ACE-FTS instruments. The results indicate that WACCM-D improves the <span class="hlt">modeling</span> of {HNO3}, {HCl}, {ClO}, {OH}, and {NOx} during the SPE. For example, Northern Hemispheric {HNO3} from WACCM-D shows an increase by two orders of magnitude at 40-70 km compared to WACCM, reaching 2.6 ppbv, in agreement with the observations. Based on our results, WACCM-D provides a state-of-the-art global representation of D-region ion chemistry and improves <span class="hlt">modeling</span> of EPP <span class="hlt">atmospheric</span> effects considerably.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1204103','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1204103"><span>Sensitivity of precipitation to parameter values in the <span class="hlt">community</span> <span class="hlt">atmosphere</span> <span class="hlt">model</span> version 5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Johannesson, Gardar; Lucas, Donald; Qian, Yun; Swiler, Laura Painton; Wildey, Timothy Michael</p> <p>2014-03-01</p> <p>One objective of the Climate Science for a Sustainable Energy Future (CSSEF) program is to develop the capability to thoroughly test and understand the uncertainties in the overall climate <span class="hlt">model</span> and its components as they are being developed. The focus on uncertainties involves sensitivity analysis: the capability to determine which input parameters have a major influence on the output responses of interest. This report presents some initial sensitivity analysis results performed by Lawrence Livermore National Laboratory (LNNL), Sandia National Laboratories (SNL), and Pacific Northwest National Laboratory (PNNL). In the 2011-2012 timeframe, these laboratories worked in collaboration to perform sensitivity analyses of a set of CAM5, 2° runs, where the response metrics of interest were precipitation metrics. The three labs performed their sensitivity analysis (SA) studies separately and then compared results. Overall, the results were quite consistent with each other although the methods used were different. This exercise provided a robustness check of the global sensitivity analysis metrics and identified some strongly influential parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A41K3207M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A41K3207M"><span>Regional Biases in Droplet Activation Parameterizations: Strong Influence on Aerosol Second Indirect Effect in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> v5.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morales, R.; Nenes, A.</p> <p>2014-12-01</p> <p>Aerosol-cloud interactions constitute one of the most uncertain aspects of anthropogenic climate change estimates. The magnitude of these interactions as represented in climate <span class="hlt">models</span> strongly depends on the process of aerosol activation. This process is the most direct physical link between aerosols and cloud microphysical properties. Calculation of droplet number in GCMs requires the computation of new droplet formation (i.e., droplet activation), through physically based activation parameterizations. Considerable effort has been placed in ensuring that droplet activation parameterizations have a physically consistent response to changes in aerosol number concentration. However, recent analyses using an adjoint sensitivity approach showed that parameterizations can exhibit considerable biases in their response to other aerosol properties, such as aerosol modal diameter or to the aerosol chemical composition. This is a potentially important factor in estimating aerosol indirect effects since changes in aerosol properties from pre-industrial times to present day exhibit a very strong regional signature. In this work we use the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5) to show that the regional imprint of the changes in aerosol properties during the last century interacts with the droplet activation parameterization in a way that these biases are amplified over climatically relevant regions. Two commonly used activation routines, the CAM5 default, Abdul-Razzak and Ghan parameterization, as well as the Fountoukis and Nenes parameterization are used in this study. We further explored the impacts of Nd parameterization biases in the first and second aerosol indirect effects separately, by performing simulations were droplet number was not allowed to intervene in the precipitation initiation process. The simulations performed show that an unphysical response to changes in the diameter of accumulation mode aerosol translates into extremely high Nd concentrations over South</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040085958','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040085958"><span><span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Aerocapture</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Duvall, Aleta L.; Keller, Vernon W.</p> <p>2004-01-01</p> <p>There are eight destinations in the solar System with sufficient <span class="hlt">atmosphere</span> for aerocapture to be a viable aeroassist option - Venus, Earth, Mars, Jupiter, Saturn and its moon Titan, Uranus, and Neptune. Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for four of these targets (Earth, Mars, Titan, and Neptune) have been developed for NASA to support systems analysis studies of potential future aerocapture missions. Development of a similar <span class="hlt">atmospheric</span> <span class="hlt">model</span> for Venus has recently commenced. An important capability of all of these <span class="hlt">models</span> is their ability to simulate quasi-random density perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithm, and for thermal systems design. Similarities and differences among these <span class="hlt">atmospheric</span> <span class="hlt">models</span> are presented, with emphasis on the recently developed Neptune <span class="hlt">model</span> and on planned characteristics of the Venus <span class="hlt">model</span>. Example applications for aerocapture are also presented and illustrated. Recent updates to the Titan <span class="hlt">atmospheric</span> <span class="hlt">model</span> are discussed, in anticipation of applications for trajectory and <span class="hlt">atmospheric</span> reconstruct of Huygens Probe entry at Titan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1059192','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1059192"><span>Sensitivity Studies of Dust Ice Nuclei Effect on Cirrus Clouds with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, Xiaohong; Shi, Xiangjun; Zhang, Kai; Jensen, Eric; Gettelman, A.; Barahona, Donifan; Nenes, Athanasios; Lawson, Paul</p> <p>2012-12-19</p> <p>In this study the effect of dust aerosol on upper tropospheric cirrus clouds through heterogeneous ice nucleation is investigated in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> version 5 (CAM5) with two ice nucleation parameterizations. Both parameterizations consider homogeneous and heterogeneous nucleation and the competition between the two mechanisms in cirrus clouds, but differ significantly in the number concentration of heterogeneous ice nuclei (IN) from dust. Heterogeneous nucleation on dust aerosol reduces the occurrence frequency of homogeneous nucleation and thus the ice crystal number concentration in the Northern Hemisphere (NH) cirrus clouds compared to simulations with pure homogeneous nucleation. Global and annual mean shortwave and longwave cloud forcing are reduced by up to 2.0 ± 0.1 W m-2 (1σ uncertainty) and 2.4 ± 0.1 W m-2, respectively due to the presence of dust IN, with the net cloud forcing change of -0.40 ± 0.20 W m-2. Comparison of <span class="hlt">model</span> simulations with in situ aircraft data obtained in NH mid-latitudes suggests that homogeneous ice nucleation may play an important role in the ice nucleation at these regions with temperatures of 205–230 K. However, simulations overestimate observed ice crystal number concentrations in the tropical tropopause regions with temperatures of 190–205 K, and overestimate the frequency of occurrence of high ice crystal number concentration (> 200 L-1) and underestimate the frequency of low ice crystal number concentration (< 30 L-1) at NH mid-latitudes. These results highlight the importance of quantifying the number concentrations and properties of heterogeneous IN (including dust aerosol) in the upper troposphere from the global perspective.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140001044','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140001044"><span>Sensitivity Studies of Dust Ice Nuclei Effect on Cirrus Clouds with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Liu, Xiaohong; Zhang, Kai; Jensen, Eric J.; Gettelman, Andrew; Barahona, Donifan; Nenes, Athanasios; Lawson, Paul</p> <p>2012-01-01</p> <p>In this study the effect of dust aerosol on upper tropospheric cirrus clouds through heterogeneous ice nucleation is investigated in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> version 5 (CAM5) with two ice nucleation parameterizations. Both parameterizations consider homogeneous and heterogeneous nucleation and the competition between the two mechanisms in cirrus clouds, but differ significantly in the number concentration of heterogeneous ice nuclei (IN) from dust. Heterogeneous nucleation on dust aerosol reduces the occurrence frequency of homogeneous nucleation and thus the ice crystal number concentration in the Northern Hemisphere (NH) cirrus clouds compared to simulations with pure homogeneous nucleation. Global and annual mean shortwave and longwave cloud forcing are reduced by up to 2.0+/-0.1Wm (sup-2) (1 uncertainty) and 2.4+/-0.1Wm (sup-2), respectively due to the presence of dust IN, with the net cloud forcing change of -0.40+/-0.20W m(sup-2). Comparison of <span class="hlt">model</span> simulations with in situ aircraft data obtained in NH mid-latitudes suggests that homogeneous ice nucleation may play an important role in the ice nucleation at these regions with temperatures of 205-230 K. However, simulations overestimate observed ice crystal number concentrations in the tropical tropopause regions with temperatures of 190- 205 K, and overestimate the frequency of occurrence of high ice crystal number concentration (greater than 200 L(sup-1) and underestimate the frequency of low ice crystal number concentration (less than 30 L(sup-1) at NH mid-latitudes. These results highlight the importance of quantifying the number concentrations and properties of heterogeneous IN (including dust aerosol) in the upper troposphere from the global perspective.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A53F0195C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A53F0195C"><span>Preliminary Results from the Testing of a Third-order Turbulence Closure in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheng, A.; Xu, K.</p> <p>2012-12-01</p> <p>This presentation describes the implementation and testing of a higher-order turbulence closure, an intermediately-prognostic higher-order turbulence closure (IPHOC), into the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM) version 5 (CAM5). The third-order turbulence closure introduces a joint double-Gaussian distribution of liquid water potential temperature, total water mixing ratio, and vertical velocity to represent any skewed turbulence circulations. The distribution is inferred from the first-, second-, and third-order moments of the variables given above and is used to diagnose cloud fraction and grid-mean liquid water mixing ratio, as well as the buoyancy term and fourth-order terms in the equations describing the evolution of the second- and third-order moments. In addition, a prognostic planetary boundary layer (PBL) height approach has been incorporated in IPHOC in order to resolve the strong inversion above PBL for the coarse general circulation <span class="hlt">model</span> (GCM) vertical grid-spacing. The IPHOC replaces PBL, shallow convection, and cloud macrophysics parameterizations in CAM5. The coupling of CAM5 with IPHOC (CAM5-IPHOC) represents a more unified treatment of boundary layer and shallow convective processes. Results from global simulations are presented and suggest that CAM5-IPHOC can provide a better treatment of boundary layer clouds and processes, when compared to CAM5. At the GCSS/WGNE Pacific Cross-Section Intercomparison (GPCI) cross section, CAM5-IPHOC tends to correct the underestimate of the stratocumulus and shallow cumulus clouds both in cloud cover and liquid water path by CAM5. The decoupling of stratocumulus clouds and the associated transition from stratocumulus-to-shallow cumulus clouds are also more realistic and reasonable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1295964-parametric-sensitivity-analysis-precipitation-global-local-scales-community-atmosphere-model-cam5','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1295964-parametric-sensitivity-analysis-precipitation-global-local-scales-community-atmosphere-model-cam5"><span>Parametric Sensitivity Analysis of Precipitation at Global and Local Scales in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Qian, Yun; Yan, Huiping; Hou, Zhangshuan; ...</p> <p>2015-04-10</p> <p>We investigate the sensitivity of precipitation characteristics (mean, extreme and diurnal cycle) to a set of uncertain parameters that influence the qualitative and quantitative behavior of the cloud and aerosol processes in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5). We adopt both the Latin hypercube and quasi-Monte Carlo sampling approaches to effectively explore the high-dimensional parameter space and then conduct two large sets of simulations. One set consists of 1100 simulations (cloud ensemble) perturbing 22 parameters related to cloud physics and convection, and the other set consists of 256 simulations (aerosol ensemble) focusing on 16 parameters related to aerosols and cloud microphysics.more » Results show that for the 22 parameters perturbed in the cloud ensemble, the six having the greatest influences on the global mean precipitation are identified, three of which (related to the deep convection scheme) are the primary contributors to the total variance of the phase and amplitude of the precipitation diurnal cycle over land. The extreme precipitation characteristics are sensitive to a fewer number of parameters. The precipitation does not always respond monotonically to parameter change. The influence of individual parameters does not depend on the sampling approaches or concomitant parameters selected. Generally the GLM is able to explain more of the parametric sensitivity of global precipitation than local or regional features. The total explained variance for precipitation is primarily due to contributions from the individual parameters (75-90% in total). The total variance shows a significant seasonal variability in the mid-latitude continental regions, but very small in tropical continental regions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780021754','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780021754"><span><span class="hlt">Atmospheric</span> prediction <span class="hlt">model</span> survey</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wellck, R. E.</p> <p>1976-01-01</p> <p>As part of the SEASAT Satellite program of NASA, a survey of representative primitive equation <span class="hlt">atmospheric</span> prediction <span class="hlt">models</span> that exist in the world today was written for the Jet Propulsion Laboratory. Seventeen <span class="hlt">models</span> developed by eleven different operational and research centers throughout the world are included in the survey. The surveys are tutorial in nature describing the features of the various <span class="hlt">models</span> in a systematic manner.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040111367&hterms=Tamas&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DTamas','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040111367&hterms=Tamas&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DTamas"><span><span class="hlt">Modeling</span> of Cometary <span class="hlt">Atmospheres</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gombosi, Tamas</p> <p>2004-01-01</p> <p>The NASA supported project '<span class="hlt">Modeling</span> of Cometary <span class="hlt">Atmospheres</span>' has been quite successful in broadening our understanding of the cometary environment. We list peer reviewed publications and conference presentation that have been made as a result of studies performed under this project. Following the list we present details of a selection of the results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950012619','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950012619"><span>Solar flare <span class="hlt">model</span> <span class="hlt">atmospheres</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hawley, Suzanne L.; Fisher, George H.</p> <p>1993-01-01</p> <p>Solar flare <span class="hlt">model</span> <span class="hlt">atmospheres</span> computed under the assumption of energetic equilibrium in the chromosphere are presented. The <span class="hlt">models</span> use a static, one-dimensional plane parallel geometry and are designed within a physically self-consistent coronal loop. Assumed flare heating mechanisms include collisions from a flux of non-thermal electrons and x-ray heating of the chromosphere by the corona. The heating by energetic electrons accounts explicitly for variations of the ionized fraction with depth in the <span class="hlt">atmosphere</span>. X-ray heating of the chromosphere by the corona incorporates a flare loop geometry by approximating distant portions of the loop with a series of point sources, while treating the loop leg closest to the chromospheric footpoint in the plane-parallel approximation. Coronal flare heating leads to increased heat conduction, chromospheric evaporation and subsequent changes in coronal pressure; these effects are included self-consistently in the <span class="hlt">models</span>. Cooling in the chromosphere is computed in detail for the important optically thick HI, CaII and MgII transitions using the non-LTE prescription in the program MULTI. Hydrogen ionization rates from x-ray photo-ionization and collisional ionization by non-thermal electrons are included explicitly in the rate equations. The <span class="hlt">models</span> are computed in the 'impulsive' and 'equilibrium' limits, and in a set of intermediate 'evolving' states. The impulsive <span class="hlt">atmospheres</span> have the density distribution frozen in pre-flare configuration, while the equilibrium <span class="hlt">models</span> assume the entire <span class="hlt">atmosphere</span> is in hydrostatic and energetic equilibrium. The evolving <span class="hlt">atmospheres</span> represent intermediate stages where hydrostatic equilibrium has been established in the chromosphere and corona, but the corona is not yet in energetic equilibrium with the flare heating source. Thus, for example, chromospheric evaporation is still in the process of occurring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020092087','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020092087"><span>Reference and Standard <span class="hlt">Atmosphere</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, Dale L.; Roberts, Barry C.; Vaughan, William W.; Parker, Nelson C. (Technical Monitor)</p> <p>2002-01-01</p> <p>This paper describes the development of standard and reference <span class="hlt">atmosphere</span> <span class="hlt">models</span> along with the history of their origin and use since the mid 19th century. The first "Standard <span class="hlt">Atmospheres</span>" were established by international agreement in the 1920's. Later some countries, notably the United States, also developed and published "Standard <span class="hlt">Atmospheres</span>". The term "Reference <span class="hlt">Atmospheres</span>" is used to identify <span class="hlt">atmosphere</span> <span class="hlt">models</span> for specific geographical locations. Range Reference <span class="hlt">Atmosphere</span> <span class="hlt">Models</span> developed first during the 1960's are examples of these descriptions of the <span class="hlt">atmosphere</span>. This paper discusses the various <span class="hlt">models</span>, scopes, applications and limitations relative to use in aerospace industry activities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSA51A2036M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSA51A2036M"><span>Initial Examination of the Long Term Thermosphere Changes As Seen in the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> - eXtended (WACCM-X) J. M. McInerney, L. Qian, and H.-L Liu</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McInerney, J. M.; Qian, L.; Liu, H.</p> <p>2013-12-01</p> <p>It has been over two decades since the projection that, not only will the human induced increase in <span class="hlt">atmospheric</span> CO2 produce a warming in the troposphere, it will also produce a cooling in the middle to upper <span class="hlt">atmosphere</span> into the 21st century with significant consequences. The thermospheric density decrease associated with this projected upper <span class="hlt">atmosphere</span> cooling due to greenhouse gases has been confirmed by observations, in particular satellite drag measurements, and by various <span class="hlt">modeling</span> studies. Recent studies also suggest potential impacts from the lower <span class="hlt">atmosphere</span> on thermosphere dynamics such as <span class="hlt">atmospheric</span> thermal tides and gravity waves. With the current advance of whole <span class="hlt">atmosphere</span> climate <span class="hlt">models</span> which extend from the ground through the thermosphere, it is now possible to include effects of these and other lower <span class="hlt">atmosphere</span> processes in <span class="hlt">modeling</span> studies of long term thermospheric changes. One such whole <span class="hlt">atmosphere</span> <span class="hlt">model</span> under development at the National Center for <span class="hlt">Atmospheric</span> Research (NCAR) is the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> - eXtended (WACCM-X). WACCM-X is a self consistent climate <span class="hlt">model</span> extending from the ground to approximately 500 kilometers and is based on the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM) / <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM) component of the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM). Although an interactive ionosphere module is not complete, the globally averaged structure of thermosphere temperature and neutral species from WACCM-X are reasonable compared with the NCAR global mean <span class="hlt">model</span>. In this study, we will examine a transient WACCM-X simulation from 1955 to 2005 with realistic tropospheric CO2 input and solar and geomagnetic forcing. The preliminary study will focus on the long term changes in the thermosphere from this simulation, in particular the secular changes of thermosphere neutral density and temperature due to anthropogenic forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030064962','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030064962"><span><span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Engineering Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, Dale L.; Roberts, Barry C.; Vaughan, William W.; Justus, C. G.</p> <p>2002-01-01</p> <p>This paper will review the historical development of reference and standard <span class="hlt">atmosphere</span> <span class="hlt">models</span> and their applications. The evolution of the U.S. Standard <span class="hlt">Atmosphere</span> will be addressed, along with the Range Reference <span class="hlt">Atmospheres</span> and, in particular, the NASA Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (GRAM). The extensive scope and content of the GRAM will be addressed since it represents the most extensive and complete 'Reference' <span class="hlt">atmosphere</span> <span class="hlt">model</span> in use today. Its origin was for engineering applications and that remains today as its principal use.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1072868','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1072868"><span>Implementation of the chemistry module MECCA (v2.5) in the modal aerosol version of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> component (v3.6.33) of the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Long, M. S.; Keene, W. C.; Easter, Richard C.; Sander, R.; Kergweg, A.; Erickson, D.; Liu, Xiaohong; Ghan, Steven J.</p> <p>2013-02-22</p> <p>A coupled <span class="hlt">atmospheric</span> chemistry and climate system <span class="hlt">model</span> was developed using the modal aerosol version of the National Center for <span class="hlt">Atmospheric</span> Research <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (modal-CAM; v3.6.33) and the Max Planck Institute for Chemistry’s Module Efficiently Calculating the Chemistry of the <span class="hlt">Atmosphere</span> (MECCA; v2.5) to provide enhanced resolution of multiphase processes, particularly those involving inorganic halogens, and associated impacts on <span class="hlt">atmospheric</span> composition and climate. Three Rosenbrock solvers (Ros-2, Ros-3, RODAS-3) were tested in conjunction with the basic load-balancing options available to modal-CAM (1) to establish an optimal configuration of the implicitly-solved multiphase chemistry module that maximizes both computational speed and repeatability of Ros- 2 and RODAS-3 results versus Ros-3, and (2) to identify potential implementation strategies for future versions of this and similar coupled systems. RODAS-3 was faster than Ros-2 and Ros-3 with good reproduction of Ros-3 results, while Ros-2 was both slower and substantially less reproducible relative to Ros-3 results. Modal-CAM with MECCA chemistry was a factor of 15 slower than modal-CAM using standard chemistry. MECCA chemistry integration times demonstrated a systematic frequency distribution for all three solvers, and revealed that the change in run-time performance was due to a change in the frequency distribution of chemical integration times; the peak frequency was similar for all solvers. This suggests that efficient chemistry-focused load-balancing schemes can be developed that rely on the parameters of this frequency distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JAMES...9..949N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JAMES...9..949N"><span>Evaluating hydrological processes in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Version 5 (CAM5) using stable isotope ratios of water</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nusbaumer, Jesse; Wong, Tony E.; Bardeen, Charles; Noone, David</p> <p>2017-06-01</p> <p>Water isotope-enabled climate and earth system <span class="hlt">models</span> are able to directly simulate paleoclimate proxy records to aid in climate reconstruction. A less used major advantage is that water isotopologues provide an independent constraint on many <span class="hlt">atmospheric</span> and hydrologic processes, allowing the <span class="hlt">model</span> to be developed and tuned in a more physically accurate way. This paper describes the new isotope-enabled CAM5 <span class="hlt">model</span>, including its isotopic physics routines, and its ability to simulate the modern distribution of water isotopologues in vapor and precipitation. It is found that the <span class="hlt">model</span> has a negative isotopic bias in precipitation. This bias is partially attributed to <span class="hlt">model</span> overestimates of deep convection, particularly over the midlatitude oceans during winter. This was determined by examining isotope ratios both in precipitation and vapor, instead of precipitation alone. This enhanced convective activity depletes the isotopic water vapor in the lower troposphere, where the majority of poleward moisture transport occurs, resulting in the insufficient transport of water isotopologue mass poleward and landward. This analysis also demonstrates that large-scale dynamical or moisture source changes can impact isotopologue values as much as local shifts in temperature or precipitation amount. The diagnosis of limitations in the large-scale transport characteristics has major implications if one is using isotope-enabled climate <span class="hlt">models</span> to examine paleoclimate proxy records, as well as the modern global hydroclimate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1226386-quantifying-sources-black-carbon-western-north-america-using-observationally-based-analysis-emission-tagging-technique-community-atmosphere-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1226386-quantifying-sources-black-carbon-western-north-america-using-observationally-based-analysis-emission-tagging-technique-community-atmosphere-model"><span>Quantifying sources of black carbon in western North America using observationally based analysis and an emission tagging technique in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Zhang, Rudong; Wang, Hailong; Hegg, D. A.; ...</p> <p>2015-11-18</p> <p>The <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5), equipped with a technique to tag black carbon (BC) emissions by source regions and types, has been employed to establish source–receptor relationships for <span class="hlt">atmospheric</span> BC and its deposition to snow over western North America. The CAM5 simulation was conducted with meteorological fields constrained by reanalysis for year 2013 when measurements of BC in both near-surface air and snow are available for <span class="hlt">model</span> evaluation. We find that CAM5 has a significant low bias in predicted mixing ratios of BC in snow but only a small low bias in predicted <span class="hlt">atmospheric</span> concentrations over northwestern USA and westernmore » Canada. Even with a strong low bias in snow mixing ratios, radiative transfer calculations show that the BC-in-snow darkening effect is substantially larger than the BC dimming effect at the surface by <span class="hlt">atmospheric</span> BC. Local sources contribute more to near-surface <span class="hlt">atmospheric</span> BC and to deposition than distant sources, while the latter are more important in the middle and upper troposphere where wet removal is relatively weak. Fossil fuel (FF) is the dominant source type for total column BC burden over the two regions. FF is also the dominant local source type for BC column burden, deposition, and near-surface BC, while for all distant source regions combined the contribution of biomass/biofuel (BB) is larger than FF. An observationally based positive matrix factorization (PMF) analysis of the snow-impurity chemistry is conducted to quantitatively evaluate the CAM5 BC source-type attribution. Furthermore, while CAM5 is qualitatively consistent with the PMF analysis with respect to partitioning of BC originating from BB and FF emissions, it significantly underestimates the relative contribution of BB. In addition to a possible low bias in BB emissions used in the simulation, the <span class="hlt">model</span> is likely missing a significant source of snow darkening from local soil found in the observations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1243191','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1243191"><span>Description and evaluation of a new four-mode version of the Modal Aerosol Module (MAM4) within version 5.3 of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, X.; Ma, P. -L.; Wang, H.; Tilmes, S.; Singh, B.; Easter, R. C.; Ghan, S. J.; Rasch, P. J.</p> <p>2016-02-08</p> <p><p><span class="hlt">Atmospheric</span> carbonaceous aerosols play an important role in the climate system by influencing the Earth's radiation budgets and modifying the cloud properties. Despite the importance, their representations in large-scale <span class="hlt">atmospheric</span> <span class="hlt">models</span> are still crude, which can influence <span class="hlt">model</span> simulated burden, lifetime, physical, chemical and optical properties, and the climate forcing of carbonaceous aerosols. In this study, we improve the current three-mode version of the Modal Aerosol Module (MAM3) in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5) by introducing an additional primary carbon mode to explicitly account for the microphysical ageing of primary carbonaceous aerosols in the <span class="hlt">atmosphere</span>. Compared to MAM3, the four-mode version of MAM (MAM4) significantly increases the column burdens of primary particulate organic matter (POM) and black carbon (BC) by up to 40 % in many remote regions, where in-cloud scavenging plays an important role in determining the aerosol concentrations. Differences in the column burdens for other types of aerosol (e.g., sulfate, secondary organic aerosols, mineral dust, sea salt) are less than 1 %. Evaluating the MAM4 simulation against in situ surface and aircraft observations, we find that MAM4 significantly improves the simulation of seasonal variation of near-surface BC concentrations in the polar regions, by increasing the BC concentrations in all seasons and particularly in cold seasons. However, it exacerbates the overestimation of <span class="hlt">modeled</span> BC concentrations in the upper troposphere in the Pacific regions. As a result, the comparisons suggest that, to address the remaining <span class="hlt">model</span> POM and BC biases, future improvements are required related to (1) in-cloud scavenging and vertical transport in convective clouds and (2) emissions of anthropogenic and biomass burning aerosols.</p></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1243191-description-evaluation-new-four-mode-version-modal-aerosol-module-mam4-within-version-community-atmosphere-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1243191-description-evaluation-new-four-mode-version-modal-aerosol-module-mam4-within-version-community-atmosphere-model"><span>Description and evaluation of a new four-mode version of the Modal Aerosol Module (MAM4) within version 5.3 of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Liu, X.; Ma, P. -L.; Wang, H.; ...</p> <p>2016-02-08</p> <p><span class="hlt">Atmospheric</span> carbonaceous aerosols play an important role in the climate system by influencing the Earth's radiation budgets and modifying the cloud properties. Despite the importance, their representations in large-scale <span class="hlt">atmospheric</span> <span class="hlt">models</span> are still crude, which can influence <span class="hlt">model</span> simulated burden, lifetime, physical, chemical and optical properties, and the climate forcing of carbonaceous aerosols. In this study, we improve the current three-mode version of the Modal Aerosol Module (MAM3) in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5) by introducing an additional primary carbon mode to explicitly account for the microphysical ageing of primary carbonaceous aerosols in the <span class="hlt">atmosphere</span>. Compared to MAM3,more » the four-mode version of MAM (MAM4) significantly increases the column burdens of primary particulate organic matter (POM) and black carbon (BC) by up to 40 % in many remote regions, where in-cloud scavenging plays an important role in determining the aerosol concentrations. Differences in the column burdens for other types of aerosol (e.g., sulfate, secondary organic aerosols, mineral dust, sea salt) are less than 1 %. Evaluating the MAM4 simulation against in situ surface and aircraft observations, we find that MAM4 significantly improves the simulation of seasonal variation of near-surface BC concentrations in the polar regions, by increasing the BC concentrations in all seasons and particularly in cold seasons. However, it exacerbates the overestimation of <span class="hlt">modeled</span> BC concentrations in the upper troposphere in the Pacific regions. As a result, the comparisons suggest that, to address the remaining <span class="hlt">model</span> POM and BC biases, future improvements are required related to (1) in-cloud scavenging and vertical transport in convective clouds and (2) emissions of anthropogenic and biomass burning aerosols.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890002769','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890002769"><span>High altitude <span class="hlt">atmospheric</span> <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hedin, Alan E.</p> <p>1988-01-01</p> <p>Five empirical <span class="hlt">models</span> were compared with 13 data sets, including both <span class="hlt">atmospheric</span> drag-based data and mass spectrometer data. The most recently published <span class="hlt">model</span>, MSIS-86, was found to be the best <span class="hlt">model</span> overall with an accuracy around 15 percent. The excellent overall agreement of the mass spectrometer-based MSIS <span class="hlt">models</span> with the drag data, including both the older data from orbital decay and the newer accelerometer data, suggests that the absolute calibration of the (ensemble of) mass spectrometers and the assumed drag coefficient in the atomic oxygen regime are consistent to 5 percent. This study illustrates a number of reasons for the current accuracy limit such as calibration accuracy and unmodeled trends. Nevertheless, the largest variations in total density in the thermosphere are accounted for, to a very high degree, by existing <span class="hlt">models</span>. The greatest potential for improvements is in areas where we still have insufficient data (like the lower thermosphere or exosphere), where there are disagreements in technique (such as the exosphere) which can be resolved, or wherever generally more accurate measurements become available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930033087&hterms=climate+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dclimate%2Bresearch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930033087&hterms=climate+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dclimate%2Bresearch"><span>Validation of cloud forcing simulated by the National Center for <span class="hlt">Atmospheric</span> Research <span class="hlt">Community</span> Climate <span class="hlt">Model</span> using observations from the Earth Radiation Budget Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Soden, B. J.</p> <p>1992-01-01</p> <p>Satellite measurements of the effect of clouds on the top of <span class="hlt">atmosphere</span> radiative energy budget are used to validate <span class="hlt">model</span> simulations from the National Center for <span class="hlt">Atmospheric</span> Research <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (NCAR CCM). The ability of the NCAR CCM to reproduce the monthly mean global distribution and temporal variability on both daily and seasonal time scales is assessed. The comparison reveals several deficiencies in the CCM cloud representation. Most notable are the difficulties in properly simulating the effect of clouds on the planetary albedo. This problem arises from discrepancies in the <span class="hlt">model</span>'s portrayal of low-level cloudiness and leads to significant errors in the absorbed solar radiation simulated by the <span class="hlt">model</span>. The CCM performs much better in simulating the effect of clouds on the longwave radiation emitted to space, indicating its relative success in capturing the vertical distribution of cloudiness. The daily variability of the radiative effects of clouds in both the shortwave and longwave spectral regions is systematically overestimated. Analysis of the seasonal variations illustrates a distinct lack of coupling in the seasonal changes in the radiative effects of cloudiness between the tropics and mid-latitudes and between the Northern and Southern Hemisphere. Much of this problem also arises from difficulties in simulating low-level cloudiness, placing further emphasis on the need for better <span class="hlt">model</span> parameterizations of boundary layer clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930033087&hterms=earth+radiation+budget&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dearth%2Bradiation%2Bbudget','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930033087&hterms=earth+radiation+budget&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dearth%2Bradiation%2Bbudget"><span>Validation of cloud forcing simulated by the National Center for <span class="hlt">Atmospheric</span> Research <span class="hlt">Community</span> Climate <span class="hlt">Model</span> using observations from the Earth Radiation Budget Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Soden, B. J.</p> <p>1992-01-01</p> <p>Satellite measurements of the effect of clouds on the top of <span class="hlt">atmosphere</span> radiative energy budget are used to validate <span class="hlt">model</span> simulations from the National Center for <span class="hlt">Atmospheric</span> Research <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (NCAR CCM). The ability of the NCAR CCM to reproduce the monthly mean global distribution and temporal variability on both daily and seasonal time scales is assessed. The comparison reveals several deficiencies in the CCM cloud representation. Most notable are the difficulties in properly simulating the effect of clouds on the planetary albedo. This problem arises from discrepancies in the <span class="hlt">model</span>'s portrayal of low-level cloudiness and leads to significant errors in the absorbed solar radiation simulated by the <span class="hlt">model</span>. The CCM performs much better in simulating the effect of clouds on the longwave radiation emitted to space, indicating its relative success in capturing the vertical distribution of cloudiness. The daily variability of the radiative effects of clouds in both the shortwave and longwave spectral regions is systematically overestimated. Analysis of the seasonal variations illustrates a distinct lack of coupling in the seasonal changes in the radiative effects of cloudiness between the tropics and mid-latitudes and between the Northern and Southern Hemisphere. Much of this problem also arises from difficulties in simulating low-level cloudiness, placing further emphasis on the need for better <span class="hlt">model</span> parameterizations of boundary layer clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A51T..05Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A51T..05Z"><span>Improved Radiation Simulation in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> with Implementation of Four-Stream Spherical Harmonic Expansion Approximation for Solar Radiation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, W.; Peng, Y.; Li, J.; Wang, B.</p> <p>2015-12-01</p> <p>The most important source of energy that drives <span class="hlt">atmospheric</span> circulation in the climate system is solar radiation. The key of its simulation is the radiative transfer process which is prescribed by a differential-integral equation. A two-stream method is widely used in solving radiative transfer equation in Global Climate <span class="hlt">Models</span>, but it may produce relative errors up to 20% under cloudy-sky condition. In order to improve the accuracy of the radiative simulation in CAM5 (Version 5.0 of <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span>), a four-stream Spherical Harmonic Expansion approximation for solar radiation is implemented. The more accurate method needs the higher moment of phase function. In this case, a parameterization of full four-stream cloud optical properties is developed. Exact Mie calculation is performed to get the extinction, scattering cross sections and phase function at numerous wavelengths across the solar spectrum. The band results of expansion coefficients parameterized by polynomials are obtained by averaging the wavelengths within each band. That involves the weighting factor of solar flux incident at 500hPa for solar zenith angle of 48.19° (Cronin 2014). By using column radiative <span class="hlt">model</span> for different solar zenith angles, <span class="hlt">atmospheric</span> profiles and aerosol conditions, it shows that the four-stream method can reduce the flux biases when aerosol is considered under clear sky. Implementation of the method in single column <span class="hlt">model</span> indicates more accuracy than the original two-stream one when comparing with ARM data. Improvements are also inferred in validation of global climate <span class="hlt">model</span> using ERBE and CERES data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920015950','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920015950"><span>Climate and <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1992-01-01</p> <p>The climate and <span class="hlt">atmosphere</span> <span class="hlt">modeling</span> research programs have concentrated on the development of appropriate <span class="hlt">atmospheric</span> and upper ocean <span class="hlt">models</span>, and preliminary applications of these <span class="hlt">models</span>. Principal <span class="hlt">models</span> are a one-dimensional radiative-convective <span class="hlt">model</span>, a three-dimensional global <span class="hlt">model</span>, and an upper ocean <span class="hlt">model</span>. Principal applications were the study of the impact of CO2, aerosols, and the solar 'constant' on climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1326808-bayesian-optimization-community-land-model-simulated-biosphere-atmosphere-exchange-using-co2-observations-from-dense-tower-network-aircraft-campaigns-over-oregon','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1326808-bayesian-optimization-community-land-model-simulated-biosphere-atmosphere-exchange-using-co2-observations-from-dense-tower-network-aircraft-campaigns-over-oregon"><span>Bayesian optimization of the <span class="hlt">Community</span> Land <span class="hlt">Model</span> simulated biosphere-<span class="hlt">atmosphere</span> exchange using CO2 observations from a dense tower network and aircraft campaigns over Oregon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Schmidt, Andres; Law, Beverly E.; Göckede, Mathias; ...</p> <p>2016-09-15</p> <p>Here, the vast forests and natural areas of the Pacific Northwest comprise one of the most productive ecosystems in the northern hemisphere. The heterogeneous landscape of Oregon poses a particular challenge to ecosystem <span class="hlt">models</span>. We present a framework using a scaling factor Bayesian inversion to improve the <span class="hlt">modeled</span> <span class="hlt">atmosphere</span>-biosphere exchange of carbon dioxide. Observations from 5 CO/CO2 towers, eddy covariance towers, and airborne campaigns were used to constrain the <span class="hlt">Community</span> Land <span class="hlt">Model</span> CLM4.5 simulated terrestrial CO2 exchange at a high spatial and temporal resolution (1/24°, 3-hourly). To balance aggregation errors and the degrees of freedom in the inverse <span class="hlt">modeling</span> system,more » we applied an unsupervised clustering approach for the spatial structuring of our <span class="hlt">model</span> domain. Data from flight campaigns were used to quantify the uncertainty introduced by the Lagrangian particle dispersion <span class="hlt">model</span> that was applied for the inversions. The average annual statewide net ecosystem productivity (NEP) was increased by 32% to 29.7 TgC per year by assimilating the tropospheric mixing ratio data. The associated uncertainty was decreased by 28.4% to 29%, on average over the entire Oregon <span class="hlt">model</span> domain with the lowest uncertainties of 11% in western Oregon. The largest differences between posterior and prior CO2 fluxes were found for the Coast Range ecoregion of Oregon that also exhibits the highest availability of <span class="hlt">atmospheric</span> observations and associated footprints. In this area, covered by highly productive Douglas-fir forest, the differences between the prior and posterior estimate of NEP averaged 3.84 TgC per year during the study period from 2012 through 2014.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ACP....17.4731W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ACP....17.4731W"><span>Direct comparisons of ice cloud macro- and microphysical properties simulated by the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 with HIPPO aircraft observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Chenglai; Liu, Xiaohong; Diao, Minghui; Zhang, Kai; Gettelman, Andrew; Lu, Zheng; Penner, Joyce E.; Lin, Zhaohui</p> <p>2017-04-01</p> <p>In this study we evaluate cloud properties simulated by the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5) using in situ measurements from the HIAPER Pole-to-Pole Observations (HIPPO) campaign for the period of 2009 to 2011. The <span class="hlt">modeled</span> wind and temperature are nudged towards reanalysis. <span class="hlt">Model</span> results collocated with HIPPO flight tracks are directly compared with the observations, and <span class="hlt">model</span> sensitivities to the representations of ice nucleation and growth are also examined. Generally, CAM5 is able to capture specific cloud systems in terms of vertical configuration and horizontal extension. In total, the <span class="hlt">model</span> reproduces 79.8 % of observed cloud occurrences inside <span class="hlt">model</span> grid boxes and even higher (94.3 %) for ice clouds (T ≤ -40 °C). The missing cloud occurrences in the <span class="hlt">model</span> are primarily ascribed to the fact that the <span class="hlt">model</span> cannot account for the high spatial variability of observed relative humidity (RH). Furthermore, <span class="hlt">model</span> RH biases are mostly attributed to the discrepancies in water vapor, rather than temperature. At the micro-scale of ice clouds, the <span class="hlt">model</span> captures the observed increase of ice crystal mean sizes with temperature, albeit with smaller sizes than the observations. The <span class="hlt">model</span> underestimates the observed ice number concentration (Ni) and ice water content (IWC) for ice crystals larger than 75 µm in diameter. <span class="hlt">Modeled</span> IWC and Ni are more sensitive to the threshold diameter for autoconversion of cloud ice to snow (Dcs), while simulated ice crystal mean size is more sensitive to ice nucleation parameterizations than to Dcs. Our results highlight the need for further improvements to the sub-grid RH variability and ice nucleation and growth in the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880002217','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880002217"><span>Thermal <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, Hollis Ralph</p> <p>1987-01-01</p> <p>The static thermal <span class="hlt">atmosphere</span> is described and its predictions are compared to observations both to test the validity of the classic assumptions and to distinguish and describe those spectral features with diagnostic value.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy..tmp..342L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..342L"><span>The impact of changes in parameterizations of surface drag and vertical diffusion on the large-scale circulation in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Feiyu; Liu, Zhengyu; Liu, Yun; Zhang, Shaoqing; Jacob, Robert</p> <p>2016-08-01</p> <p>Simulations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5) are used to analyze the sensitivity of the large-scale circulation to changes in parameterizations of orographic surface drag and vertical diffusion. Many GCMs and NWP <span class="hlt">models</span> use enhanced turbulent mixing in stable conditions to improve simulations, while CAM5 cuts off all turbulence at high stabilities and instead employs a strong orographic surface stress parameterization, known as turbulent mountain stress (TMS). TMS completely dominates the surface stress over land and reduces the near-surface wind speeds compared to simulations without TMS. It is found that TMS is generally beneficial for the large-scale circulation as it improves zonal wind speeds, Arctic sea level pressure and zonal anomalies of the 500-hPa stream function, compared to ERA-Interim. It also alleviates <span class="hlt">atmospheric</span> blocking frequency biases in the Northern Hemisphere. Using a scheme that instead allows for a modest increase of turbulent diffusion at higher stabilities only in the planetary boundary layer (PBL) appears to in some aspects have a similar, although much smaller, beneficial effect as TMS. Enhanced mixing throughout the <span class="hlt">atmospheric</span> column, however, degrades the CAM5 simulation. Evaluating the simulations in comparison with detailed measurements at two locations reveals that TMS is detrimental for the PBL at the flat grassland ARM Southern Great Plains site, giving too strong wind turning and too deep PBLs. At the Sodankylä forest site, the effect of TMS is smaller due to the larger local vegetation roughness. At both sites, all simulations substantially overestimate the boundary layer ageostrophic flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1253683','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1253683"><span>Testing ice microphysics parameterizations in the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Version 3 using Tropical Warm Pool-International Cloud Experiment data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Weiguo; Liu, Xiaohong; Xie, Shaocheng; Boyle, Jim; McFarlane, Sally A.</p> <p>2009-07-23</p> <p>Here, cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single-column version of NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> version 3 (CAM3). For comparison, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations compared favorably with observations during the Tropical Warm Pool–International Cloud Experiment by the U.S. Department of Energy <span class="hlt">Atmospheric</span> Radiation Measurement Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within the mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) contents are similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and ice water content extends 2 km further downward, which is in better agreement with observations. The dependence of the frozen water mass fraction on temperature from the new scheme is also in better agreement with available observations. Outgoing longwave radiation (OLR) at the top of the <span class="hlt">atmosphere</span> (TOA) from the simulation with the new scheme is, in general, larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice crystal effective radius contribute significantly to the difference in the calculations of TOA OLR, in addition to cloud water path. Numerical experiments show that cloud properties in the new scheme can respond reasonably to changes in the concentration of aerosols and emphasize the importance of correctly simulating aerosol effects in climate <span class="hlt">models</span> for aerosol-cloud interactions. Further evaluation, especially for ice cloud properties based on in-situ data, is needed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1253683-testing-ice-microphysics-parameterizations-ncar-community-atmospheric-model-version-using-tropical-warm-pool-international-cloud-experiment-data','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1253683-testing-ice-microphysics-parameterizations-ncar-community-atmospheric-model-version-using-tropical-warm-pool-international-cloud-experiment-data"><span>Testing ice microphysics parameterizations in the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Version 3 using Tropical Warm Pool-International Cloud Experiment data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Wang, Weiguo; Liu, Xiaohong; Xie, Shaocheng; ...</p> <p>2009-07-23</p> <p>Here, cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single-column version of NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> version 3 (CAM3). For comparison, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations compared favorably with observations during the Tropical Warm Pool–International Cloud Experiment by the U.S. Department of Energy <span class="hlt">Atmospheric</span> Radiation Measurement Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within themore » mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) contents are similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and ice water content extends 2 km further downward, which is in better agreement with observations. The dependence of the frozen water mass fraction on temperature from the new scheme is also in better agreement with available observations. Outgoing longwave radiation (OLR) at the top of the <span class="hlt">atmosphere</span> (TOA) from the simulation with the new scheme is, in general, larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice crystal effective radius contribute significantly to the difference in the calculations of TOA OLR, in addition to cloud water path. Numerical experiments show that cloud properties in the new scheme can respond reasonably to changes in the concentration of aerosols and emphasize the importance of correctly simulating aerosol effects in climate <span class="hlt">models</span> for aerosol-cloud interactions. Further evaluation, especially for ice cloud properties based on in-situ data, is needed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.3741L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.3741L"><span>The impact of changes in parameterizations of surface drag and vertical diffusion on the large-scale circulation in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lindvall, Jenny; Svensson, Gunilla; Caballero, Rodrigo</p> <p>2017-06-01</p> <p>Simulations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (CAM5) are used to analyze the sensitivity of the large-scale circulation to changes in parameterizations of orographic surface drag and vertical diffusion. Many GCMs and NWP <span class="hlt">models</span> use enhanced turbulent mixing in stable conditions to improve simulations, while CAM5 cuts off all turbulence at high stabilities and instead employs a strong orographic surface stress parameterization, known as turbulent mountain stress (TMS). TMS completely dominates the surface stress over land and reduces the near-surface wind speeds compared to simulations without TMS. It is found that TMS is generally beneficial for the large-scale circulation as it improves zonal wind speeds, Arctic sea level pressure and zonal anomalies of the 500-hPa stream function, compared to ERA-Interim. It also alleviates <span class="hlt">atmospheric</span> blocking frequency biases in the Northern Hemisphere. Using a scheme that instead allows for a modest increase of turbulent diffusion at higher stabilities only in the planetary boundary layer (PBL) appears to in some aspects have a similar, although much smaller, beneficial effect as TMS. Enhanced mixing throughout the <span class="hlt">atmospheric</span> column, however, degrades the CAM5 simulation. Evaluating the simulations in comparison with detailed measurements at two locations reveals that TMS is detrimental for the PBL at the flat grassland ARM Southern Great Plains site, giving too strong wind turning and too deep PBLs. At the Sodankylä forest site, the effect of TMS is smaller due to the larger local vegetation roughness. At both sites, all simulations substantially overestimate the boundary layer ageostrophic flow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1050658','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1050658"><span>Impact of horizontal resolution on simulation of precipitation extremes in an aqua-planet version of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, F.; Collins, W.D.; Wehner, M.F.; Williamson, D.L.; Olson, J.G.; Algieri, C.</p> <p>2011-03-01</p> <p>One key question regarding current climate <span class="hlt">models</span> is whether the projection of climate extremes converges to a realistic representation as the spatial and temporal resolutions of the <span class="hlt">model</span> are increased. Ideally the <span class="hlt">model</span> extreme statistics should approach a fixed distribution once the resolutions are commensurate with the characteristic length and time scales of the processes governing the formation of the extreme phenomena of interest. In this study, a series of AGCM runs with idealized 'aquaplanet-steady-state' boundary conditions have been performed with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM3 to investigate the effect of horizontal resolution on climate extreme simulations. The use of the aquaplanet framework highlights the roles of <span class="hlt">model</span> physics and dynamics and removes any apparent convergence in extreme statistics due to better resolution of surface boundary conditions and other external inputs. Assessed at a same large spatial scale, the results show that the horizontal resolution and time step have strong effects on the simulations of precipitation extremes. The horizontal resolution has a much stronger impact on precipitation extremes than on mean precipitation. Updrafts are strongly correlated with extreme precipitation at tropics at all the resolutions, while positive low-tropospheric temperature anomalies are associated with extreme precipitation at mid-latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750011035','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750011035"><span><span class="hlt">Models</span> of Mars' <span class="hlt">atmosphere</span> (1974)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1974-01-01</p> <p><span class="hlt">Atmospheric</span> <span class="hlt">models</span> for support of design and mission planning of space vehicles that are to orbit the planet Mars, enter its <span class="hlt">atmosphere</span>, or land on the surface are presented. Quantitative data for the Martian <span class="hlt">atmosphere</span> were obtained from Earth-base observations and from spacecraft that have orbited Mars or passed within several planetary radii. These data were used in conjunction with existing theories of planetary <span class="hlt">atmospheres</span> to predict other characteristics of the Martian <span class="hlt">atmosphere</span>. Earth-based observations provided information on the composition, temperature, and optical properties of Mars with rather coarse spatial resolution, whereas spacecraft measurements yielded data on composition, temperature, pressure, density, and <span class="hlt">atmospheric</span> structure with moderately good spatial resolution. The <span class="hlt">models</span> provide the temperature, pressure, and density profiles required to perform basic aerodynamic analyses. The profiles are supplemented by computed values of viscosity, specific heat, and speed of sound.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1170098','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1170098"><span>Aerosol Effects on Cirrus through Ice Nucleation in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5 with a Statistical Cirrus Scheme</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Minghuai; Liu, Xiaohong; Zhang, Kai; Comstock, Jennifer M.</p> <p>2014-09-01</p> <p>A statistical cirrus cloud scheme that tracks ice saturation ratio in the clear-sky and cloudy portion of a grid box separately has been implemented into NCAR CAM5 to provide a consistent treatment of ice nucleation and cloud formation. Simulated ice supersaturation and ice crystal number concentrations strongly depend on the number concentrations of heterogeneous ice nuclei (IN), subgrid temperature formulas and the number concentration of sulfate particles participating in homogeneous freezing, while simulated ice water content is insensitive to these perturbations. 1% to 10% dust particles serving as heterogeneous IN is 20 found to produce ice supersaturaiton in better agreement with observations. Introducing a subgrid temperature perturbation based on long-term aircraft observations of meso-scale motion produces a better hemispheric contrast in ice supersaturation compared to observations. Heterogeneous IN from dust particles significantly alter the net radiative fluxes at the top of <span class="hlt">atmosphere</span> (TOA) (-0.24 to -1.59 W m-2) with a significant clear-sky longwave component (0.01 to -0.55 W m-2). Different cirrus treatments significantly perturb the net TOA anthropogenic aerosol forcing from -1.21 W m-2 to -1.54 W m-2, with a standard deviation of 0.10 W m-2. Aerosol effects on cirrus clouds exert an even larger impact on the <span class="hlt">atmospheric</span> component of the radiative fluxes (two or three times the changes in the TOA radiative fluxes) and therefore on the hydrology cycle through the fast <span class="hlt">atmosphere</span> response. This points to the urgent need to quantify aerosol effects on cirrus clouds through ice nucleation and how these further affect the hydrological cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130000643','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130000643"><span><span class="hlt">Modeling</span> of <span class="hlt">Atmosphere</span> Revitalization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coker, Robert; Knox, James; Kittredge, Kenneth</p> <p>2012-01-01</p> <p>NASA's AES is pioneering new approaches for future human missions beyond Earth orbit. All spacecraft systems must be minimized with respect to mass, power, and volume. Here, we show work related to improving system efficiency and reliability for water separation systems on crewed vehicles and the initial development of COMSOL simulations in support of the <span class="hlt">Atmosphere</span> Revitalization Recovery and Environmental Monitoring (ARREM) project</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015BGeo...12.6337W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015BGeo...12.6337W"><span>Characterization of active and total fungal <span class="hlt">communities</span> in the <span class="hlt">atmosphere</span> over the Amazon rainforest</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Womack, A. M.; Artaxo, P. E.; Ishida, F. Y.; Mueller, R. C.; Saleska, S. R.; Wiedemann, K. T.; Bohannan, B. J. M.; Green, J. L.</p> <p>2015-11-01</p> <p>Fungi are ubiquitous in the <span class="hlt">atmosphere</span> and may play an important role in <span class="hlt">atmospheric</span> processes. We investigated the composition and diversity of fungal <span class="hlt">communities</span> over the Amazon rainforest canopy and compared these <span class="hlt">communities</span> to fungal <span class="hlt">communities</span> found in terrestrial environments. We characterized the total fungal <span class="hlt">community</span> and the metabolically active portion of the <span class="hlt">community</span> using high-throughput DNA and RNA sequencing and compared these data to predictions generated by a mass-balance <span class="hlt">model</span>. We found that the total <span class="hlt">community</span> was primarily comprised of fungi from the phylum Basidiomycota. In contrast, the active <span class="hlt">community</span> was primarily composed of members of the phylum Ascomycota and included a high relative abundance of lichen fungi, which were not detected in the total <span class="hlt">community</span>. The relative abundance of Basidiomycota and Ascomycota in the total and active <span class="hlt">communities</span> was consistent with our <span class="hlt">model</span> predictions, suggesting that this result was driven by the relative size and number of spores produced by these groups. When compared to other environments, fungal <span class="hlt">communities</span> in the <span class="hlt">atmosphere</span> were most similar to <span class="hlt">communities</span> found in tropical soils and leaf surfaces. Our results demonstrate that there are significant differences in the composition of the total and active fungal <span class="hlt">communities</span> in the <span class="hlt">atmosphere</span>, and that lichen fungi, which have been shown to be efficient ice nucleators, may be abundant members of active <span class="hlt">atmospheric</span> fungal <span class="hlt">communities</span> over the forest canopy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1087809','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1087809"><span>The Role of Circulation Features on Black Carbon Transport into the Arctic in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Version 5 (CAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ma, Po-Lun; Rasch, Philip J.; Wang, Hailong; Zhang, Kai; Easter, Richard C.; Tilmes, S.; Fast, Jerome D.; Liu, Xiaohong; Yoon, Jin-Ho; Lamarque, Jean-Francois</p> <p>2013-05-28</p> <p>Current climate <span class="hlt">models</span> generally under-predict the surface concentration of black carbon (BC) in the Arctic due to the uncertainties associated with emissions, transport, and removal. This bias is also present in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Version 5.1 (CAM5). In this study, we investigate the uncertainty of Arctic BC due to transport processes simulated by CAM5 by configuring the <span class="hlt">model</span> to run in an “offline mode” in which the large-scale circulations are prescribed. We compare the simulated BC transport when the offline <span class="hlt">model</span> is driven by the meteorology predicted by the standard free-running CAM5 with simulations where the meteorology is constrained to agree with reanalysis products. Some circulation biases are apparent: the free-running CAM5 produces about 50% less transient eddy transport of BC than the reanalysis-driven simulations, which may be attributed to the coarse <span class="hlt">model</span> resolution insufficient to represent eddies. Our analysis shows that the free-running CAM5 reasonably captures the essence of the Arctic Oscillation (AO), but some discernable differences in the spatial pattern of the AO between the free-running CAM5 and the reanalysis-driven simulations result in significantly different AO modulation of BC transport over Northeast Asia and Eastern Europe. Nevertheless, we find that the overall climatological circulation patterns simulated by the free-running CAM5 generally resembles those from the reanalysis products, and BC transport is very similar in both simulation sets. Therefore, the simulated circulation features regulating the long-range BC transport is unlikely the most important cause of the large under-prediction of surface BC concentration in the Arctic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFMIN43B1183D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFMIN43B1183D"><span>Extending <span class="hlt">Atmospheric</span> Composition Processing to the <span class="hlt">Community</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Durbin, P.; Tilmes, C.; Balsano, R.; Martin, A.; Soika, V.; Inskeep, E.</p> <p>2007-12-01</p> <p>The Ozone Monitoring Instrument Science Investigator-led Processing System (OMI SIPS) has been the central data processing system for OMI since its launch on NASA's Aura spacecraft in July, 2004. As part of NASA's evolution from mission based processing to measurement based processing, we are evolving the system into a <span class="hlt">community</span> oriented <span class="hlt">Atmospheric</span> Composition Processing System (ACPS). This involves changing focus from the mission (OMI) to the measurement (total column ozone), and a widening of our focus from the mission science teams to the overall scientific <span class="hlt">community</span>. The current system dispatches and executes software developed by scientists on a computer cluster; archiving the results and distributing the data to numerous parties. Although this works well for the production environment, access to centralized systems has been naturally limited. Ideally, scientists should be able to easily get the data, run their software, make changes and repeat the process until they are happy with the solution to the problems they are trying to solve. In addition it should be simple to migrate research improvements from the <span class="hlt">community</span> back into the formal production system. Through NASA's "Advancing Collaborative Connections for Earth-Sun System Science," we have extended publicly accessible interfaces into the production system. The system provides an open API via a set of SOAP/XML and REST based web services, enabling scientists, researchers and operators to interact directly with the data and services offered by the central system. The system includes metadata, archive, and planner subsystems. The metadata server stores metadata about the data products and provides the ability for processing software to evaluate production rules to determine the appropriate input data files for a given data processing job. The archive server stores the data files themselves and makes then available for clients to retrieve the files as needed. The planner plans out the set of jobs to be run</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EOSTr..94..284S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EOSTr..94..284S"><span>Lagrangian <span class="hlt">Modeling</span> of the <span class="hlt">Atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultz, Colin</p> <p>2013-08-01</p> <p>Like watching a balloon borne by the breeze, a Lagrangian <span class="hlt">model</span> tracks a parcel of air as it flows through the <span class="hlt">atmosphere</span>. Whether running forward or backward in time, Lagrangian <span class="hlt">models</span> offer a powerful tool for tracking and understanding the fates, or origins, of <span class="hlt">atmospheric</span> flows. In the AGU monograph Lagrangian <span class="hlt">Modeling</span> of the <span class="hlt">Atmosphere</span>, editors John Lin, Dominik Brunner, Christoph Gerbig, Andreas Stohl, Ashok Luhar, and Peter Webley explore the nuances of the <span class="hlt">modeling</span> technique. In this interview Eos talks to Lin about the growing importance of Lagrangian <span class="hlt">modeling</span> as the world settles on climate change mitigation strategies, the societal value of operational <span class="hlt">modeling</span>, and how recent advances are making it possible to run these complex calculations at home.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012GMDD....5.1743B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GMDD....5.1743B"><span>Unified parameterization of the planetary boundary layer and shallow convection with a higher-order turbulence closure in the <span class="hlt">community</span> <span class="hlt">atmosphere</span> <span class="hlt">model</span>: single column experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bogenschutz, P. A.; Gettelman, A.; Morrison, H.; Larson, V. E.; Schanen, D. P.; Meyer, N. R.; Craig, C.</p> <p>2012-07-01</p> <p>This paper describes the coupling of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM) version 5 with a unified multi-variate probability density function (PDF) parameterization, Cloud Layers Unified by Binormals (CLUBB). CLUBB replaces the planetary boundary layer (PBL), shallow convection, and cloud macrophysics schemes in CAM5 with a higher-order turbulence closure based on an assumed PDF. Comparisons of single-column versions of CAM5 and CAM-CLUBB are provided in this paper for several boundary layer regimes. As compared to Large Eddy Simulations (LES), CAM-CLUBB and CAM5 simulate marine stratocumulus regimes with similar accuracy. For shallow convective regimes, CAM-CLUBB improves the representation of cloud cover and liquid water path (LWP). In addition, for shallow convection CAM-CLUBB offers better fidelity for sub-grid scale vertical velocity, which is an important input for aerosol activation. Finally, CAM-CLUBB results are more robust to changes in vertical and temporal resolution when compared to CAM5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012GMD.....5.1407B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GMD.....5.1407B"><span>Unified parameterization of the planetary boundary layer and shallow convection with a higher-order turbulence closure in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span>: single-column experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bogenschutz, P. A.; Gettelman, A.; Morrison, H.; Larson, V. E.; Schanen, D. P.; Meyer, N. R.; Craig, C.</p> <p>2012-11-01</p> <p>This paper describes the coupling of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM) version 5 with a unified multi-variate probability density function (PDF) parameterization, Cloud Layers Unified by Binormals (CLUBB). CLUBB replaces the planetary boundary layer (PBL), shallow convection, and cloud macrophysics schemes in CAM5 with a higher-order turbulence closure based on an assumed PDF. Comparisons of single-column versions of CAM5 and CAM-CLUBB are provided in this paper for several boundary layer regimes. As compared to large eddy simulations (LESs), CAM-CLUBB and CAM5 simulate marine stratocumulus regimes with similar accuracy. For shallow convective regimes, CAM-CLUBB improves the representation of cloud cover and liquid water path (LWP). In addition, for shallow convection CAM-CLUBB offers better fidelity for subgrid-scale vertical velocity, which is an important input for aerosol activation. Finally, CAM-CLUBB results are more robust to changes in vertical and temporal resolution when compared to CAM5.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.A43C0322B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.A43C0322B"><span>Forecast experiments with the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM) over the Tropical Warm Pool - International Cloud Experiment (TWP-ICE)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boyle, J. S.; Klein, S.</p> <p>2008-12-01</p> <p>The Tropical Warm Pool International Cloud Experiment (TWP-ICE) experiment took place over 20 January 2006 to 14 February 2006 centered on Darwin, Australia. The motivation behind the design of the observations for TWP-ICE was to better understand the factors that control tropical convection. Additionally, the experiment sought to describe how the characteristics of the convection affect the microphysics of the clouds, particularly the deep convective anvils and tropical cirrus. A chief goal of the TWP-ICE was to provide information of the tropical processes for the improvement of the parameterization of clouds in numerical weather prediction (NWP) and climate <span class="hlt">models</span>. The TWP-ICE experiment combined aspects of previous observational campaigns, specifically the combination of a dense rawindsonde network, high altitude aircraft sampling and airborne and ground based radar and lidar also observations from geostationary and polar obrbiting satellites were used. The CAM experiments consisted of changing the cloud microphysics parameterizations and running with three different horizontal resolutions. The CAM simulations were performed using the finite volume dynamical core with grids of 1.9° x 2.5°, 0.9° x 1.25° and 0.47° x 0.63°. The cloud microphysics parameterizations used were the default CAM single moment scheme and a new double moment parameterization that predicts both the number and mass of liquid and ice condensate.The <span class="hlt">model</span> was initialized by the state variables (wind, temperature, moisture and surface pressure) taken from the ECMWF operational analyses. The forecasts are for 5 days starting at 00Z. The results presented will focus on the short term day 1 ( 24-48h) of the forecasts. The validation of cloud properities requires the coordination of several different observational platforms, including the a millimeter Cloud radar and microwave radiometer at Darwin as well as rawindsondes. The new microphysics scheme produces better estimates of the cloud</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A43F0297W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A43F0297W"><span>Direct Comparisons of Ice Cloud Microphysical Properties Simulated by the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> CAM5 with ARM SPartICus Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, C.; Liu, X.; Zhang, K.; Diao, M.; Gettelman, A.</p> <p>2016-12-01</p> <p>Cirrus clouds in the upper troposphere play a key role in the Earth radiation budget, and their radiative forcing depends strongly on number concentration and size distribution of ice particles. In this study we evaluate the cloud microphysical properties simulated by the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5.4 (CAM5) against the Small Particles in Cirrus (SPartICus) observations over the ARM South Great Plain (SGP) site between January and June 2010. <span class="hlt">Model</span> simulation is performed using specific dynamics to preserve prognostic meteorology (U, V, and T) close to GEOS-5 analysis. <span class="hlt">Model</span> results collocated with SPartICus flight tracks spatially and temporally are directly compared with the observations. We compare CAM5 simulated ice crystal number concentration (Ni), ice particle size distribution, ice water content (IWC), and Ni co-variances with temperature and vertical velocity with the statistics from SPartICus observations. All analyses are restricted to T ≤ -40°C and in a 6°×6° area centered at SGP. <span class="hlt">Model</span> sensitivity tests are performed with different ice nucleation mechanisms and with the effects of pre-existing ice crystals to reflect the uncertainties in cirrus parameterizations. In addition, different threshold size for autoconversion of cloud ice to snow (Dcs) is also tested. We find that (1) a distinctly high Ni (100-1000 L-1) often occurred in the observations but is significantly underestimated in the <span class="hlt">model</span>, which may be due to the smaller relative humidity with respect to ice (RHi) in the simulation that could suppress the homogeneous nucleation, (2) a positive correlation exists between Ni and vertical velocity variance (σw) at horizontal scales up to 50 km in the observation, and the <span class="hlt">model</span> can reproduce this relationship but tends to underestimate Ni when σw is relatively small, (3) simulated Ni differs greatly among the sensitive experiments, and simulated IWC is also sensitive to the cirrus parameterizations but to a lesser extent. Moreover</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.4187H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.4187H"><span>Can high resolution climate simulations with the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM) offer a new perspective on 21st century mitigation scenarios ?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hannay, Cécile; Bacmeister, Julio; Neale, Richard; Truesdale, John; Gettelman, Andrew; O'Neill, Brian</p> <p>2014-05-01</p> <p>Present-day climate simulations using the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM) show that some aspects of the simulated climate are improved in response to increased horizontal resolution (Bacmeister et al, 2014). Increased resolution allows us to explicitly resolve tropical cyclones (TC) and study TC statistics. Present-day climate simulation with CAM5 at 25 km captures TC statistics reasonably well, suggesting that CAM5 is a good candidate to look at these storm statistics in a changing climate. Other features of the present-day simulation with CAM5 at 25km also clearly improve due to better representation of topography or better simulation of regional circulations. This is the case for the Summer Indian Monsoon and the wintertime precipitation over the Southeast United States. Despite these improvements, it is important to note that some aspects of the simulation do not improve and even deteriorate. For instance, the double ITCZ is exacerbated and large biases in summertime precipitation over the central US remain. Because the high resolution simulation is more realistic in terms of reproducing intense storms and fields strongly influenced by the topography or regional circulation, they offer a new perspective to look at these aspects for the twenty-first-century representative concentration pathway (RCP). A major objective for running these higher resolution RCP scenario experiments is to provide more detailed information as to the difference in mitigation cost between scenarios. Here we examine time-slice simulations of the end of the 20th and 21st centuries (using the RCP4.5 and RCP8.5 scenarios). We use 20-year uncoupled simulations with CAM5 at 25 km using prescribed sea surface temperatures (SSTs) and sea-ice extent. For the 20th century run, prescribed SSTs and sea-ice are coming from observations. For the 21st century, SSTs and sea-ice are extracted from RCP fully coupled runs at lower resolution and are corrected by the present-day <span class="hlt">model</span> bias. We assess how</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760020658','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760020658"><span><span class="hlt">Models</span> for infrared <span class="hlt">atmospheric</span> radiation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tiwari, S. N.</p> <p>1976-01-01</p> <p>Line and band <span class="hlt">models</span> for infrared spectral absorption are discussed. Radiative transmittance and integrated absorptance of Lorentz, Doppler, and voigt line profiles were compared for a range of parameters. It was found that, for the intermediate path lengths, the combined Lorentz-Doppler (Voigt) profile is essential in calculating the <span class="hlt">atmospheric</span> transmittance. Narrow band <span class="hlt">model</span> relations for absorptance were used to develop exact formulations for total absorption by four wide band <span class="hlt">models</span>. Several continuous correlations for the absorption of a wide band <span class="hlt">model</span> were compared with the numerical solutions of the wide band <span class="hlt">models</span>. By employing the line-by-line and quasi-random band <span class="hlt">model</span> formulations, computational procedures were developed for evaluating transmittance and upwelling <span class="hlt">atmospheric</span> radiance. Homogeneous path transmittances were calculated for selected bands of CO, CO2, and N2O and compared with experimental measurements. The upwelling radiance and signal change in the wave number interval of the CO fundamental band were also calculated.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6035661','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6035661"><span><span class="hlt">Modeling</span> oceanic and <span class="hlt">atmospheric</span> vortices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dritschel, D.G.; Legras, B. CNRS, Lab. de Meteorologie Dynamique, Paris )</p> <p>1993-03-01</p> <p>Numerical <span class="hlt">modeling</span> and prediction of coherent structures in geophysical fluid dynamics is reviewed. Numerical computation is widely used in geophysical fluid dynamics due to the nonlinear behaviour of the systems studied and the complexity of the mathematical <span class="hlt">models</span> used. Idealized systems and the determination of potential vorticity in simplified <span class="hlt">atmospheric</span> <span class="hlt">models</span> are discussed. <span class="hlt">Atmospheric</span> vortex structures, their interactions, and the effects on weather are described. A quasigeostrophic <span class="hlt">model</span> is used to illustrate the effect of trophospherically generated disturbances on the polar vortex using the contour dynamics numerical method. A comparison of numerical techniques for simulating the evolution of neighboring vortices of unequal size is given. Future developments in the use of numerical <span class="hlt">models</span> in geophysical fluid dynamics and weather prediction are discussed. 15 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1054783','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1054783"><span>Old-field <span class="hlt">Community</span>, Climate and <span class="hlt">Atmospheric</span> Manipulation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Aimee Classen</p> <p>2009-11-01</p> <p>We are in the process of finishing a number of laboratory, growth chamber and greenhouse projects, analyzing data, and writing papers. The projects reported addressed these subjects: How do climate and <span class="hlt">atmospheric</span> changes alter aboveground plant biomass and <span class="hlt">community</span> structure; Effects of multiple climate changes factors on plant <span class="hlt">community</span> composition and diversity: what did we learn from a 5-year open-top chamber experiment using constructed old-field <span class="hlt">communities</span>; Do <span class="hlt">atmospheric</span> and climatic change factors interact to alter woody seedling emergence, establishment and productivity; Soil moisture surpasses elevated CO{sub 2} and temperature in importance as a control on soil carbon dynamics; How do climate and <span class="hlt">atmospheric</span> changes alter belowground root and fungal biomass; How do climate and <span class="hlt">atmospheric</span> changes alter soil microarthropod and microbial <span class="hlt">communities</span>; How do climate and <span class="hlt">atmospheric</span> changes alter belowground microbial function; Linking root litter diversity and microbial functioning at a micro scale under current and projected CO{sub 2} concentrations; Multifactor climate change effects on soil ecosystem functioning depend on concurrent changes in plant <span class="hlt">community</span> composition; How do climate and <span class="hlt">atmospheric</span> changes alter aboveground insect populations; How do climate and <span class="hlt">atmospheric</span> changes alter festuca endophyte infection; How do climate and <span class="hlt">atmospheric</span> changes soil carbon stabilization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A42F..07D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A42F..07D"><span>Microphysical and macrophysical characteristics of ice and mixed-phase clouds compared between in-situ observations from the NSF ORCAS campaign and the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Diao, M.; D'Alessandro, J.; Wu, C.; Liu, X.; Jensen, J. B.</p> <p>2016-12-01</p> <p>Large spatial coverage of ice and mixed-phase clouds is frequently observed in the higher latitudinal regions, especially over the Arctic and Antarctica. However, because the microphysical properties in the ice and mixed-phase clouds are highly variable in space, major challenges still remain in understanding the characteristics of ice and mixed-phase clouds on the microscale, as well as representing the sub-grid scale variabilities of relative humidity in the General Circulation <span class="hlt">Models</span>. In this work, we use the in-situ, airborne observations from the NSF O2/N2 Ratio and CO2 Airborne Southern Ocean (ORCAS) Study (January - February 2016) to analyze the microphysical and macrophysical characteristics of ice and mixed-phase clouds over the Southern Ocean. A total of 18 flights onboard the NSF Gulfstream-V research aircraft are used to quantify the cloud properties and relative humidity distributions at various temperatures, pressures and aerosol background. New QC/QA water vapor data of the Vertical Cavity Surface Emitting Laser based on the laboratory calibration in summer 2016 will be presented. The statistical distributions of cloud microphysical properties and relative humidity with respect to ice (RHi) derived from in-situ observations will be compared with the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Version 5 (CAM5). The horizontal extent of ice and mixed-phase clouds, and their formation and evolution will be derived based on the method of Diao et al. (2013). The occurrence frequency of ice supersaturation (i.e., RHi > 100%) will be examined in relation to various chemical tracers (i.e., O3 and CO) and total aerosol number concentrations (e.g., aerosols > 0.1 μm and > 0.5 μm) at clear-sky and in-cloud conditions. We will quantify whether these characteristics of ISS are scale-dependent from the microscale to the mesoscale. Overall, our work will evaluate the spatial variabilities of RHi inside/outside of ice and mixed-phase clouds, the frequency and magnitude of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007312','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007312"><span><span class="hlt">Atmospheric</span> and wind <span class="hlt">modeling</span> for ATC</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Slater, Gary L.</p> <p>1990-01-01</p> <p>The section on <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> covers the following topics: the standard <span class="hlt">atmosphere</span>, <span class="hlt">atmospheric</span> variations, <span class="hlt">atmosphere</span> requirements for ATC, and implementation of a software <span class="hlt">model</span> for Center/Tracon Advisory System (CTAS). The section on wind <span class="hlt">modeling</span> covers the following topics: wind data -- NOAA profiler system; wind profile estimation; incorporation of various data types into filtering scheme; spatial and temporal variation; and software implementation into CTAS. The appendices contain Matlab codes for <span class="hlt">atmospheric</span> routines and for wind estimation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1184955','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1184955"><span>Effects of pre-existing ice crystals on cirrus clouds and comparison between different ice nucleation parameterizations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shi, Xiangjun; Liu, Xiaohong; Zhang, Kai</p> <p>2015-02-11</p> <p>In order to improve the treatment of ice nucleation in a more realistic manner in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5.3 (CAM5.3), the effects of pre-existing ice crystals on ice nucleation in cirrus clouds are considered. In addition, by considering the in-cloud variability in ice saturation ratio, homogeneous nucleation takes place spatially only in a portion of the cirrus cloud rather than in the whole area of the cirrus cloud. Compared to observations, the ice number concentrations and the probability distributions of ice number concentration are both improved with the updated treatment. The pre-existing ice crystals significantly reduce ice number concentrations in cirrus clouds, especially at mid- to high latitudes in the upper troposphere (by a factor of ~10). Furthermore, the contribution of heterogeneous ice nucleation to cirrus ice crystal number increases considerably. <br><br> Besides the default ice nucleation parameterization of Liu and Penner (2005, hereafter LP) in CAM5.3, two other ice nucleation parameterizations of Barahona and Nenes (2009, hereafter BN) and Kärcher et al. (2006, hereafter KL) are implemented in CAM5.3 for the comparison. In-cloud ice crystal number concentration, percentage contribution from heterogeneous ice nucleation to total ice crystal number, and pre-existing ice effects simulated by the three ice nucleation parameterizations have similar patterns in the simulations with present-day aerosol emissions. However, the change (present-day minus pre-industrial times) in global annual mean column ice number concentration from the KL parameterization (3.24 × 10<sup>6</sup> m<sup>-2</sup>) is less than that from the LP (8.46 × 10<sup>6</sup> m<sup>-2</sup>) and BN (5.62 × 10<sup>6</sup> m<sup>-2</sup>) parameterizations. As a result, the experiment using the KL parameterization predicts a much smaller anthropogenic aerosol long-wave indirect forcing (0.24 W m<sup>-2</sup>) than that using the LP (0.46 W m<sup>−2</sup</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1184955-effects-pre-existing-ice-crystals-cirrus-clouds-comparison-between-different-ice-nucleation-parameterizations-community-atmosphere-model-cam5','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1184955-effects-pre-existing-ice-crystals-cirrus-clouds-comparison-between-different-ice-nucleation-parameterizations-community-atmosphere-model-cam5"><span>Effects of pre-existing ice crystals on cirrus clouds and comparison between different ice nucleation parameterizations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Shi, Xiangjun; Liu, Xiaohong; Zhang, Kai</p> <p>2015-02-11</p> <p>In order to improve the treatment of ice nucleation in a more realistic manner in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5.3 (CAM5.3), the effects of pre-existing ice crystals on ice nucleation in cirrus clouds are considered. In addition, by considering the in-cloud variability in ice saturation ratio, homogeneous nucleation takes place spatially only in a portion of the cirrus cloud rather than in the whole area of the cirrus cloud. Compared to observations, the ice number concentrations and the probability distributions of ice number concentration are both improved with the updated treatment. The pre-existing ice crystals significantly reduce ice numbermore » concentrations in cirrus clouds, especially at mid- to high latitudes in the upper troposphere (by a factor of ~10). Furthermore, the contribution of heterogeneous ice nucleation to cirrus ice crystal number increases considerably. Besides the default ice nucleation parameterization of Liu and Penner (2005, hereafter LP) in CAM5.3, two other ice nucleation parameterizations of Barahona and Nenes (2009, hereafter BN) and Kärcher et al. (2006, hereafter KL) are implemented in CAM5.3 for the comparison. In-cloud ice crystal number concentration, percentage contribution from heterogeneous ice nucleation to total ice crystal number, and pre-existing ice effects simulated by the three ice nucleation parameterizations have similar patterns in the simulations with present-day aerosol emissions. However, the change (present-day minus pre-industrial times) in global annual mean column ice number concentration from the KL parameterization (3.24 × 106 m-2) is less than that from the LP (8.46 × 106 m-2) and BN (5.62 × 106 m-2) parameterizations. As a result, the experiment using the KL parameterization predicts a much smaller anthropogenic aerosol long-wave indirect forcing (0.24 W m-2) than that using the LP (0.46 W m−2) and BN (0.39 W m-2) parameterizations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1184955','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1184955"><span>Effects of Pre-Existing Ice Crystals on Cirrus Clouds and Comparison between Different Ice Nucleation Parameterizations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM5)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shi, Xiangjun; Liu, Xiaohong; Zhang, Kai</p> <p>2015-01-01</p> <p>In order to improve the treatment of ice nucleation in a more realistic manner in the <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> version 5.3 (CAM5.3), the effects of preexisting ice crystals on ice nucleation in cirrus clouds are considered. In addition, by considering the in-cloud variability in ice saturation ratio, homogeneous nucleation takes place spatially only in a portion of cirrus cloud rather than in the whole area of cirrus cloud. With these improvements, the two unphysical limiters used in the representation of ice nucleation are removed. Compared to observations, the ice number concentrations and the probability distributions of ice number concentration are both improved with the updated treatment. The preexisting ice crystals significantly reduce ice number concentrations in cirrus clouds, especially at mid- to high latitudes in the upper troposphere (by a factor of ~10). Furthermore, the contribution of heterogeneous ice nucleation to cirrus ice crystal number increases considerably.Besides the default ice nucleation parameterization of Liu and Penner (2005, hereafter LP) in CAM5.3, two other ice nucleation parameterizations of Barahona and Nenes (2009, hereafter BN) and Kärcher et al. (2006, hereafter KL) are implemented in CAM5.3 for the comparison. In-cloud ice crystal number concentration, percentage contribution from heterogeneous ice nucleation to total ice crystal number, and preexisting ice effects simulated by the three ice nucleation parameterizations have similar patterns in the simulations with present-day aerosol emissions. However, the change (present-day minus pre-industrial times) in global annual mean column ice number concentration from the KL parameterization (3.24×106 m-2) is obviously less than that from the LP (8.46×106 m-2) and BN (5.62×106 m-2) parameterizations. As a result, experiment using the KL parameterization predicts a much smaller anthropogenic aerosol longwave indirect forcing (0.24 W m-2) than that using the LP (0.46 W m-2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.8483B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.8483B"><span>A <span class="hlt">Community</span>-oriented CEOS <span class="hlt">Atmospheric</span> Composition Portal (ACP)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bernonville, S.; Goussev, O.; Falke, S.; Lindsay, F.; Lynnes, C. S.; Yang, W.; Zhao, P.; Johnson, J.</p> <p>2012-04-01</p> <p>The <span class="hlt">Atmospheric</span> Composition Constellation (ACC) and the Workgroup for Information Systems and Services (WGISS) within the Committee on Earth Observation Satellites (CEOS) is developing a portal to support interoperability among the <span class="hlt">atmospheric</span> composition research and applications <span class="hlt">communities</span>. The CEOS <span class="hlt">Atmospheric</span> Composition Portal (ACP) is defining approaches for providing data access, tools and contextual guidance for an international suite of remote sensing datasets. An initial prototype provides access to data services and analysis tools hosted by the World Data Center for Remote Sensing of the <span class="hlt">Atmosphere</span> (WDC-RSAT), NASA's Goddard Earth Sciences Data and Information Services Center (GES DISC) and DataFed. Distributed access to data is implemented via interoperability standards, including the Open Geospatial Consortium's (OGC) Web Map Service (WMS) and Web Coverage Service (WCS). A fundamental aspect to the design, implementation and evolution of the ACP is <span class="hlt">community</span> collaboration. The portal is intended as a <span class="hlt">community</span> resource that is created through collaboration across remotely sensed <span class="hlt">atmospheric</span> composition data organizations and used by a variety of groups across the climate, air quality, and stratospheric ozone domains. The implementation of interoperability standards in the ACP has involved coordination on identifying the most applicable standards and the definition of <span class="hlt">community</span>-specific conventions to ensure consistent adoption of standards. This presentation includes an overview of the ACP, its <span class="hlt">community</span> oriented approach, and use of <span class="hlt">community</span>-conventions in achieving standards-based interoperability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010079034','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010079034"><span>Multiwavelength <span class="hlt">Modeling</span> of Nove <span class="hlt">Atmospheres</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Huschildt, P. H.</p> <p>2001-01-01</p> <p>LMC 1988 #1 was a slow, CO type, dust forming classical nova. It was the first extragalactic nova to be observed with the IUE satellite. We have successfully fitted observed ultraviolet and optical spectra of LMC 1988 #1 taken within the first two months of its outburst (when the <span class="hlt">atmosphere</span> was still optically thick) with synthetic spectra computed using PHOENIX nova <span class="hlt">model</span> <span class="hlt">atmospheres</span>. The synthetic spectra reproduce most of the features seen in the spectra and provide V band magnitudes consistent with the observed light curve. The fits are improved by increasing the CNO abundances to 10 times the solar values. The bolometric luminosity of LMC 1988 #1 was approximately constant at 2 x 10(exp 38) ergs per second at a distance of 47.3 kpc for the first 2 months of the outburst until the formation of the dust shell.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRD..118.9456F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRD..118.9456F"><span>A global <span class="hlt">atmospheric</span> <span class="hlt">model</span> of meteoric iron</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Wuhu; Marsh, Daniel R.; Chipperfield, Martyn P.; Janches, Diego; Höffner, Josef; Yi, Fan; Plane, John M. C.</p> <p>2013-08-01</p> <p>The first global <span class="hlt">model</span> of meteoric iron in the <span class="hlt">atmosphere</span> (WACCM-Fe) has been developed by combining three components: the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM), a description of the neutral and ion-molecule chemistry of iron in the mesosphere and lower thermosphere (MLT), and a treatment of the injection of meteoric constituents into the <span class="hlt">atmosphere</span>. The iron chemistry treats seven neutral and four ionized iron containing species with 30 neutral and ion-molecule reactions. The meteoric input function (MIF), which describes the injection of Fe as a function of height, latitude, and day, is precalculated from an astronomical <span class="hlt">model</span> coupled to a chemical meteoric ablation <span class="hlt">model</span> (CABMOD). This newly developed WACCM-Fe <span class="hlt">model</span> has been evaluated against a number of available ground-based lidar observations and performs well in simulating the mesospheric atomic Fe layer. The <span class="hlt">model</span> reproduces the strong positive correlation of temperature and Fe density around the Fe layer peak and the large anticorrelation around 100 km. The diurnal tide has a significant effect in the middle of the layer, and the <span class="hlt">model</span> also captures well the observed seasonal variations. However, the <span class="hlt">model</span> overestimates the peak Fe+concentration compared with the limited rocket-borne mass spectrometer data available, although good agreement on the ion layer underside can be obtained by adjusting the rate coefficients for dissociative recombination of Fe-molecular ions with electrons. Sensitivity experiments with the same chemistry in a 1-D <span class="hlt">model</span> are used to highlight significant remaining uncertainties in reaction rate coefficients, and to explore the dependence of the total Fe abundance on the MIF and rate of vertical transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20140010040&hterms=iron&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Diron','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20140010040&hterms=iron&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Diron"><span>A Global <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> of Meteoric Iron</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Feng, Wuhu; Marsh, Daniel R.; Chipperfield, Martyn P.; Janches, Diego; Hoffner, Josef; Yi, Fan; Plane, John M. C.</p> <p>2013-01-01</p> <p>The first global <span class="hlt">model</span> of meteoric iron in the <span class="hlt">atmosphere</span> (WACCM-Fe) has been developed by combining three components: the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM), a description of the neutral and ion-molecule chemistry of iron in the mesosphere and lower thermosphere (MLT), and a treatment of the injection of meteoric constituents into the <span class="hlt">atmosphere</span>. The iron chemistry treats seven neutral and four ionized iron containing species with 30 neutral and ion-molecule reactions. The meteoric input function (MIF), which describes the injection of Fe as a function of height, latitude, and day, is precalculated from an astronomical <span class="hlt">model</span> coupled to a chemical meteoric ablation <span class="hlt">model</span> (CABMOD). This newly developed WACCM-Fe <span class="hlt">model</span> has been evaluated against a number of available ground-based lidar observations and performs well in simulating the mesospheric atomic Fe layer. The <span class="hlt">model</span> reproduces the strong positive correlation of temperature and Fe density around the Fe layer peak and the large anticorrelation around 100 km. The diurnal tide has a significant effect in the middle of the layer, and the <span class="hlt">model</span> also captures well the observed seasonal variations. However, the <span class="hlt">model</span> overestimates the peak Fe+ concentration compared with the limited rocket-borne mass spectrometer data available, although good agreement on the ion layer underside can be obtained by adjusting the rate coefficients for dissociative recombination of Fe-molecular ions with electrons. Sensitivity experiments with the same chemistry in a 1-D <span class="hlt">model</span> are used to highlight significant remaining uncertainties in reaction rate coefficients, and to explore the dependence of the total Fe abundance on the MIF and rate of vertical transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6777397','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6777397"><span><span class="hlt">Atmospheric</span> <span class="hlt">modeling</span> in complex terrain</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Williams, M. D.; Streit, G. E.</p> <p>1990-05-01</p> <p>Los Alamos investigators have developed several <span class="hlt">models</span> which are relevant to <span class="hlt">modeling</span> Mexico City air quality. The collection of <span class="hlt">models</span> includes: meteorological <span class="hlt">models</span>, dispersion <span class="hlt">models</span>, air chemistry <span class="hlt">models</span>, and visibility <span class="hlt">models</span>. The <span class="hlt">models</span> have been applied in several different contexts. They have been developed primarily to address the complexities posed by complex terrain. HOTMAC is the meteorological <span class="hlt">model</span> which requires terrain and limited meteorological information. HOTMAC incorporates a relatively complete description of <span class="hlt">atmospheric</span> physics to give good descriptions of the wind, temperature, and turbulence fields. RAPTAD is a dispersion code which uses random particle transport and kernel representations to efficiently provide accurate pollutant concentration fields. RAPTAD provides a much better description of tracer dispersion than do Gaussian puff <span class="hlt">models</span> which fail to properly represent the effects of the wind profile near the surface. ATMOS and LAVM treat photochemistry and visibility respectively. ATMOS has been used to describe wintertime chemistry of the Denver brown cloud. Its description provided reasonable agreement with measurements for the high altitude of Denver. LAVM can provide both numerical indices or pictoral representations of visibility effects of pollutants. 15 refs., 74 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810036387&hterms=ph+ammonia&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dph%2Bammonia','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810036387&hterms=ph+ammonia&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dph%2Bammonia"><span><span class="hlt">Atmospheric</span> ammonia - Measurements and <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoell, J. M., Jr.; Levine, J. S.; Augustsson, T. R.; Harward, C. N.</p> <p>1981-01-01</p> <p>Ammonia possesses a unique position in the terrestrial <span class="hlt">atmosphere</span> in that it is the only gaseous basic constituent. Ammonia readily forms aerosols, and by virtue of its high solubility controls the pH of cloud droplets and precipitation. Over the past year a ground-based solar viewing Infrared Heterodyne Radiometer has been used at Langley Research Center to infer the vertical distribution of ammonia. Ground level in situ measurements of ammonia have also been obtained to supplement the profile data. The ammonia profiles have been analyzed and interpreted with a one-dimensional photochemical <span class="hlt">model</span> of the troposphere to assess the sources and sinks of NH3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1916629W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1916629W"><span>Understanding moisture recycling for <span class="hlt">atmospheric</span> river management in Amazonian <span class="hlt">communities</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weng, Wei; Luedeke, Matthias; Zemp, Delphine-Clara; Lakes, Tobia; Pradhan, Prajal; Kropp, Juergen</p> <p>2017-04-01</p> <p>The invisible <span class="hlt">atmospheric</span> transports of moisture have recently attracted more research efforts into understanding their structures, processes involved and their function as an ecosystem service. Current attention has been focused on larger scale analysis such as studying global or continental level moisture recycling. Here we applied a water balance <span class="hlt">model</span> to backtrack the flying river that sustains two local <span class="hlt">communities</span> in the Colombian and Peruvian Amazon where vulnerable <span class="hlt">communities</span> rely highly on the rainfall for agricultural practices. By utilising global precipitation (TRMM Multisatillite Precipitation Analysis; TMPA) and evapotranspiration products (Moderate Resolution Imaging Spectroradiometer MODIS, MOD16ET) as input data in the present <span class="hlt">modelling</span> experiments to compensate the sparse ground observation data in these regions, the moisture recycling process targeting the two amazonian <span class="hlt">communities</span> which has not yet been explored quantitatively has been shown. The TMPA was selected because of its proved comparativeness with observation data in its precipitation estimations over Amazon regions while the MOD16ET data was chosen for being validated by previous studies in the Amazon basin and for reported good performance. In average, 45.5 % of the precipitation occurring to Caquetá region in Colombia is of terrestrial origin from the South American continent while 48.2% of the total rainfall received by Peruvian Yurimaguas is also from the South American land sources. The spatial distribution of the precipitationsheds (defined previously as the upwind contribution of evapotranspiration to a specific location's precipitation) shows transboundary and transnational shares in the moisture contributors of the precipitation for both regions. An interesting reversed upstream-downstream roles can be observed when the upstream regions in traditional watershed thinking become downstream areas considering precipitationsheds and flying rivers. Strong seasonal variations are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050207555','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050207555"><span><span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Mars Aerocapture</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Duvall, Aleta; Keller, Vernon W.</p> <p>2005-01-01</p> <p>level Mars <span class="hlt">atmospheric</span> <span class="hlt">model</span>. Applications include systems design, performance analysis, and operations planning for aerobraking, entry descent and landing, and aerocapture. Typical Mars aerocapture periapsis altitudes (for systems with rigid- aeroshell heat shields) are about 50 km. This altitude is above the 0-40 km height range covered by Mars Global Surveyor Thermal Emission Spectrometer (TES) nadir observations. Recently, TES limb sounding data have been made available, spanning more than two Mars years (more than 200,000 data profiles) with altitude coverage up to about 60 km, well within the height range of interest for aerocapture. Results are presented comparing Mars-GRAM <span class="hlt">atmospheric</span> density with densities from TES nadir and limb sounding observations. A new Mars-GRAM feature is described which allows individual TES nadir or limb profiles to be extracted from the large TES databases, and to be used as an optional replacement for standard Mars-GRAM background (climatology) conditions. For Monte-Carlo applications such as aerocapture guidance and control studies, Mars-GRAM perturbations are available using these TES profile background conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040120869','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040120869"><span><span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Aeroentry and Aeroassist</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Duvall, Aleta; Keller, Vernon W.</p> <p>2004-01-01</p> <p>Eight destinations in the Solar System have sufficient <span class="hlt">atmosphere</span> for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for Earth, Mars, Titan, and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications. Development has begun on a similar <span class="hlt">atmospheric</span> <span class="hlt">model</span> for Venus. An important capability of these <span class="hlt">models</span> is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these <span class="hlt">atmospheric</span> <span class="hlt">models</span> are compared, and example applications for aerocapture are presented. Recent Titan <span class="hlt">atmospheric</span> <span class="hlt">model</span> updates are discussed, in anticipation of applications for trajectory and <span class="hlt">atmospheric</span> reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars <span class="hlt">atmospheric</span> <span class="hlt">model</span>, in support of future Mars aerocapture systems analysis studies, are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070014628','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070014628"><span><span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Aeroentry and Aeroassist</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Duvall, Aleta; Keller, Vernon W.</p> <p>2005-01-01</p> <p>Eight destinations in the Solar System have sufficient <span class="hlt">atmosphere</span> for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for Earth, Mars, Titan, and Neptune have been developed for use in NASA's systems analysis studies of aerocapture applications. Development has begun on a similar <span class="hlt">atmospheric</span> <span class="hlt">model</span> for Venus. An important capability of these <span class="hlt">models</span> is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these <span class="hlt">atmospheric</span> <span class="hlt">models</span> are compared, and example applications for aerocapture are presented. Recent Titan <span class="hlt">atmospheric</span> <span class="hlt">model</span> updates are discussed, in anticipation of applications for trajectory and <span class="hlt">atmospheric</span> reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars <span class="hlt">atmospheric</span> <span class="hlt">model</span>, in support of future Mars aerocapture systems analysis studies, are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A43G0326J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A43G0326J"><span>Multi-Year Application and Evaluation over U.S. using the Weather Research and Forecasting <span class="hlt">model</span> with Chemistry and the Physics/Aerosol Packages from the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (WRF-CAM5)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jena, C. K.; Zhang, Y.; Campbell, P. C.</p> <p>2016-12-01</p> <p>Multiyear applications of an online-coupled meteorological and chemical transport <span class="hlt">model</span> allow an assessment of the variation trends in simulated meteorology, air quality and their interactions over a period of time during which emissions and meteorology are changed. In this work, the Weather Research and Forecasting <span class="hlt">model</span> with Chemistry and the physics/aerosol packages of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5 (WRF-CAM5) is applied for five full years of 2008 - 2012 over U.S. to evaluate the <span class="hlt">model</span>'s capability in reproducing the observations and to examine the changes in <span class="hlt">model</span> predictions due to changes in meteorology and emissions. The <span class="hlt">model</span> predictions of meteorological, radiative, and cloud variables, chemical concentrations, and column mass abundances are evaluated against satellite data and surface measurements across U.S. A comprehensive evaluation shows overall good performance for temperature and relative humidity at 2-m, precipitation against most datasets (except for NCDC), radiation variables, cloud fraction, cloud droplet number concentration, and precipitable water vapor in terms of domain average performance statistics, multi-year trends and inter-seasonal variability. Large biases exist in surface concentrations of sulfate, elemental carbon, PM2.5 against IMPROVE and PM10, column abundances of NO2 and O3, aerosol optical depth, cloud condensation nuclei, cloud liquid and ice water paths, cloud optical thickness. These biases indicate uncertainties in the <span class="hlt">model</span> representations of boundary layer processes (e.g., surface roughness), cloud processes (e.g., microphysics and cumulus parameterization), emissions (e.g., biogenic and wildfire emissions), chemistry and aerosol treatment (e.g., winter photochemistry, aerosol thermodynamics). Overall, these results demonstrate promising skills of WRF-CAM5 for long-term simulations at a regional scale and suggest the above areas of potential improvements to further improve <span class="hlt">model</span> skill and reduce uncertainties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED458893.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED458893.pdf"><span><span class="hlt">Community</span> College <span class="hlt">Model</span> Characteristics.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Raby, Rosalind Latiner</p> <p></p> <p>This paper argues that <span class="hlt">community</span> college <span class="hlt">models</span>, especially in developing countries, can be victims of the vocational school fallacy, which holds that that two-year vocational/technical schools that ignore a general education foundation may not be an optimal means for solving worker needs. In addition, globalization has hastened a mirroring of the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1126381','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1126381"><span><span class="hlt">Atmospheric</span> cloud water contains a diverse bacterial <span class="hlt">community</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kourtev, P. S.; Hill, Kimberly A.; Shepson, Paul B.; Konopka, Allan</p> <p>2011-06-15</p> <p><span class="hlt">Atmospheric</span> cloud water contains an active microbial <span class="hlt">community</span> which can impact climate, human health and ecosystem processes in terrestrial and aquatic systems. Most studies on the composition of microbial <span class="hlt">communities</span> in clouds have been performed with orographic clouds that are typically in direct contact with the ground. We collected water samples from cumulus clouds above the upper U.S. Midwest. The cloud water was analyzed for the diversity of bacterial phylotypes by denaturing gradient gel electrophoresis (DGGE) and sequencing of 16S rRNA gene amplicons. DGGE analyses of bacterial <span class="hlt">communities</span> detected 17e21 bands per sample. Sequencing confirmed the presence of a diverse bacterial <span class="hlt">community</span>; sequences from seven bacterial phyla were retrieved. Cloud water bacterial <span class="hlt">communities</span> appeared to be dominated by members of the cyanobacteria, proteobacteria, actinobacteria and firmicutes.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740008423','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740008423"><span>Titan <span class="hlt">atmosphere</span> <span class="hlt">models</span>, 1973. [Saturn satellite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Divine, N.</p> <p>1974-01-01</p> <p>The composition and structure of the <span class="hlt">atmosphere</span> of Titan, based on theory and on spectroscopic and infrared data, is reviewed for the development of numerical engineering <span class="hlt">models</span>. Light, nominal, and heavy <span class="hlt">atmospheres</span> are described and tabulated, and their profiles of radius, temperature, pressure, and density are illustrated. Corresponding descriptions of <span class="hlt">atmospheric</span> dynamics, condensates and surfaces are outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15176199','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15176199"><span><span class="hlt">Atmospheric</span> transmittance of an absorbing gas. 6. OPTRAN status report and introduction to the NESDIS/NCEP <span class="hlt">community</span> radiative transfer <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kleespies, Thomas J; van Delst, Paul; McMillin, Larry M; Derber, John</p> <p>2004-05-20</p> <p>Since the publication of the Optical Path Transmittance (OPTRAN) algorithm [Appl. Opt. 34, 8396 (1995)], much of the code and implementation has been refined and improved. The predictor set has been expanded, an objective method to select optimal predictors has been established, and the two-interpolation method has been discarded for a single-interpolation method. The OPTRAN coefficients have been generated for a wide range of satellites and instruments. The most significant new development is the Jacobian-K-matrix version of OPTRAN, which is currently used for operational direct radiance assimilation in both the Global Data Analysis System and the ETA Data Analysis System at the National Oceanographic and <span class="hlt">Atmospheric</span> Administration, National Weather Service, National Centers for Environmental Prediction Environmental <span class="hlt">Modeling</span> Center. This paper documents these improvements and serves as a record of the current status of the operational OPTRAN code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011892','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011892"><span>Trajectory Software With Upper <span class="hlt">Atmosphere</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barrett, Charles</p> <p>2012-01-01</p> <p>The Trajectory Software Applications 6.0 for the Dec Alpha platform has an implementation of the Jacchia-Lineberry Upper <span class="hlt">Atmosphere</span> Density <span class="hlt">Model</span> used in the Mission Control Center for International Space Station support. Previous trajectory software required an upper <span class="hlt">atmosphere</span> to support <span class="hlt">atmosphere</span> drag calculations in the Mission Control Center. The Functional operation will differ depending on the end-use of the module. In general, the calling routine will use function-calling arguments to specify input to the processor. The <span class="hlt">atmosphere</span> <span class="hlt">model</span> will then compute and return <span class="hlt">atmospheric</span> density at the time of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/963593','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/963593"><span>Testing ice microphysics parameterizations in the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Version 3 using Tropical Warm Pool–International Cloud Experiment data</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang, Weiguo; Liu, Xiaohong; Xie, Shaocheng; Boyle, James; McFarlane, Sally A.</p> <p>2009-07-23</p> <p>Cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single column version of NCAR CAM3. For comparisons, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations were compared favorably with observations during the Tropical Warm Pool- International Cloud Experiment by US Department of Energy <span class="hlt">Atmospheric</span> Radiation Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within the mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) content is similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and extends 2 km further downward, which are closer to observations. The dependence of the frozen water mass fraction in total condensate on temperature from the new scheme is also closer to available observations. Outgoing longwave radiation (OLR) at the top of the <span class="hlt">atmosphere</span> (TOA) from the simulation with the new scheme is in general larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice effective radius contribute significantly to the difference in the TOA OLR in addition to cloud water path. The deep convection process affects both TOA OLR and surface downward longwave radiation. The over-frequently-triggered deep convention process in the <span class="hlt">model</span> is not the only mechanism for the excess middle and high level clouds. Further evaluation especially for ice cloud properties based on in-situ data is needed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ACP....12.7117H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ACP....12.7117H"><span>An assessment of <span class="hlt">atmospheric</span> mercury in the <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">model</span> at an urban site and a rural site in the Great Lakes Region of North America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Holloway, T.; Voigt, C.; Morton, J.; Spak, S. N.; Rutter, A. P.; Schauer, J. J.</p> <p>2012-08-01</p> <p>Quantitative analysis of three <span class="hlt">atmospheric</span> mercury species - gaseous elemental mercury (Hg0), reactive gaseous mercury (RGHg) and particulate mercury (PHg) - has been limited to date by lack of ambient measurement data as well as by uncertainties in numerical <span class="hlt">models</span> and emission inventories. This study employs the <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">Model</span> version 4.6 with mercury chemistry (CMAQ-Hg), to examine how local emissions, meteorology, <span class="hlt">atmospheric</span> chemistry, and deposition affect mercury concentration and deposition the Great Lakes Region (GLR), and two sites in Wisconsin in particular: the rural Devil's Lake site and the urban Milwaukee site. Ambient mercury exhibits significant biases at both sites. Hg0 is too low in CMAQ-Hg, with the <span class="hlt">model</span> showing a 6% low bias at the rural site and 36% low bias at the urban site. Reactive mercury (RHg = RGHg + PHg) is over-predicted by the <span class="hlt">model</span>, with annual average biases >250%. Performance metrics for RHg are much worse than for mercury wet deposition, ozone (O3), nitrogen dioxide (NO2), or sulfur dioxide (SO2). Sensitivity simulations to isolate background inflow from regional emissions suggests that oxidation of imported Hg0 dominates <span class="hlt">model</span> estimates of RHg at the rural study site (91% of base case value), and contributes 55% to the RHg at the urban site (local emissions contribute 45%).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=60858&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=60858&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>REGIONAL <span class="hlt">MODELING</span> OF THE <span class="hlt">ATMOSPHERIC</span> TRANSPORT AND DEPOSITION OF ATRAZINE</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>A version of the <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">model</span> has been developed by the U.S. EPA that is capable of addressing the <span class="hlt">atmospheric</span> fate, transport and deposition of some common trace toxics. An initial, 36-km rectangular grid-cell application for atrazine has been...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=60858&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90549710&CFTOKEN=81522402','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=60858&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90549710&CFTOKEN=81522402"><span>REGIONAL <span class="hlt">MODELING</span> OF THE <span class="hlt">ATMOSPHERIC</span> TRANSPORT AND DEPOSITION OF ATRAZINE</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>A version of the <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">model</span> has been developed by the U.S. EPA that is capable of addressing the <span class="hlt">atmospheric</span> fate, transport and deposition of some common trace toxics. An initial, 36-km rectangular grid-cell application for atrazine has been...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870000873','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870000873"><span>Optical <span class="hlt">models</span> of the molecular <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zuev, V. E.; Makushkin, Y. S.; Mitsel, A. A.; Ponomarev, Y. N.; Rudenko, V. P.; Firsov, K. M.</p> <p>1986-01-01</p> <p>The use of optical and laser methods for performing <span class="hlt">atmospheric</span> investigations has stimulated the development of the optical <span class="hlt">models</span> of the <span class="hlt">atmosphere</span>. The principles of constructing the optical <span class="hlt">models</span> of molecular <span class="hlt">atmosphere</span> for radiation with different spectral composition (wideband, narrowband, and monochromatic) are considered in the case of linear and nonlinear absorptions. The example of the development of a system which provides for the <span class="hlt">modeling</span> of the processes of optical-wave energy transfer in the <span class="hlt">atmosphere</span> is presented. Its physical foundations, structure, programming software, and functioning were considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22265305','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22265305"><span>Microbial <span class="hlt">communities</span> on Australian modified <span class="hlt">atmosphere</span> packaged Atlantic salmon.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Powell, S M; Tamplin, M L</p> <p>2012-05-01</p> <p>The role of specific spoilage organisms (SSO) in products such as Atlantic salmon has been well documented. However, little is known about what other micro-organisms are present and these organisms may indirectly influence spoilage by their interactions with the SS0. We used a combination of culture-based and DNA-based methods to explore the microbial <span class="hlt">communities</span> found on Atlantic salmon fillets packed in a modified <span class="hlt">atmosphere</span> of carbon dioxide and nitrogen. After 15 days the <span class="hlt">communities</span> were dominated by Shewanella spp. or Carnobacterium spp. and a variety of other genera were present in smaller numbers. Variability in the microbial <span class="hlt">community</span> composition in packages processed on the same day was also observed. This was mostly due to differences in the presence of minor members of the <span class="hlt">community</span> including species from genera such as Iodobacter, Serratia, Morganella and Yersinia. The combination of culture-based and culture-independent methods provided greater insight into the development of microbial <span class="hlt">communities</span> on Atlantic salmon than would have been possible using only one method. This work highlights the potential importance of lactic acid bacteria (LAB) in fresh Atlantic salmon stored under modified <span class="hlt">atmosphere</span> conditions. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1182742','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1182742"><span>Boreal lakes moderate seasonal and diurnal temperature variation and perturb <span class="hlt">atmospheric</span> circulation: Analyses in the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> 1 (CESM1)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Subin, Zachary M.; Murphy, Lisa N.; Li, Fiyu; Bonfils, Celine; Riley, William J.</p> <p>2012-01-15</p> <p>We used a lake thermal physics <span class="hlt">model</span> recently coupled into the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> 1 (CESM1) to study the effects of lake distribution in present and future climate. Under present climate, correcting the large underestimation of lake area in CESM1 (denoted CCSM4 in the configuration used here) caused 1 °C spring decreases and fall increases in surface air temperature throughout large areas of Canada and the US. Simulated summer surface diurnal air temperature range decreased by up to 4 °C, reducing CCSM4 biases. These changes were much larger than those resulting from prescribed lake disappearance in some present-day permafrost regions under doubled-CO<sub>2</sub> conditions. Correcting the underestimation of lake area in present climate caused widespread high-latitude summer cooling at 850 hPa. Significant remote changes included decreases in the strength of fall Southern Ocean westerlies. We found significantly different winter responses when separately analysing 45-yr subperiods, indicating that relatively long simulations are required to discern the impacts of surface changes on remote conditions. We also investigated the surface forcing of lakes using idealised aqua-planet experiments which showed that surface changes of 2 °C in the Northern Hemisphere extra-tropics could cause substantial changes in precipitation and winds in the tropics and Southern Hemisphere. Shifts in the Inter-Tropical Convergence Zone were opposite in sign to those predicted by some previous studies. Zonal mean circulation changes were consistent in character but much larger than those occurring in the lake distribution experiments, due to the larger magnitude and more uniform surface forcing in the idealised aqua-planet experiments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1326808','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1326808"><span>Bayesian optimization of the <span class="hlt">Community</span> Land <span class="hlt">Model</span> simulated biosphere-<span class="hlt">atmosphere</span> exchange using CO<sub>2</sub> observations from a dense tower network and aircraft campaigns over Oregon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schmidt, Andres; Law, Beverly E.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Conley, Stephen</p> <p>2016-09-15</p> <p>Here, the vast forests and natural areas of the Pacific Northwest comprise one of the most productive ecosystems in the northern hemisphere. The heterogeneous landscape of Oregon poses a particular challenge to ecosystem <span class="hlt">models</span>. We present a framework using a scaling factor Bayesian inversion to improve the <span class="hlt">modeled</span> <span class="hlt">atmosphere</span>-biosphere exchange of carbon dioxide. Observations from 5 CO/CO<sub>2</sub> towers, eddy covariance towers, and airborne campaigns were used to constrain the <span class="hlt">Community</span> Land <span class="hlt">Model</span> CLM4.5 simulated terrestrial CO<sub>2</sub> exchange at a high spatial and temporal resolution (1/24°, 3-hourly). To balance aggregation errors and the degrees of freedom in the inverse <span class="hlt">modeling</span> system, we applied an unsupervised clustering approach for the spatial structuring of our <span class="hlt">model</span> domain. Data from flight campaigns were used to quantify the uncertainty introduced by the Lagrangian particle dispersion <span class="hlt">model</span> that was applied for the inversions. The average annual statewide net ecosystem productivity (NEP) was increased by 32% to 29.7 TgC per year by assimilating the tropospheric mixing ratio data. The associated uncertainty was decreased by 28.4% to 29%, on average over the entire Oregon <span class="hlt">model</span> domain with the lowest uncertainties of 11% in western Oregon. The largest differences between posterior and prior CO<sub>2</sub> fluxes were found for the Coast Range ecoregion of Oregon that also exhibits the highest availability of <span class="hlt">atmospheric</span> observations and associated footprints. In this area, covered by highly productive Douglas-fir forest, the differences between the prior and posterior estimate of NEP averaged 3.84 TgC per year during the study period from 2012 through 2014.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1326808','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1326808"><span>Bayesian optimization of the <span class="hlt">Community</span> Land <span class="hlt">Model</span> simulated biosphere-<span class="hlt">atmosphere</span> exchange using CO<sub>2</sub> observations from a dense tower network and aircraft campaigns over Oregon</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schmidt, Andres; Law, Beverly E.; Göckede, Mathias; Hanson, Chad; Yang, Zhenlin; Conley, Stephen</p> <p>2016-09-15</p> <p>Here, the vast forests and natural areas of the Pacific Northwest comprise one of the most productive ecosystems in the northern hemisphere. The heterogeneous landscape of Oregon poses a particular challenge to ecosystem <span class="hlt">models</span>. We present a framework using a scaling factor Bayesian inversion to improve the <span class="hlt">modeled</span> <span class="hlt">atmosphere</span>-biosphere exchange of carbon dioxide. Observations from 5 CO/CO<sub>2</sub> towers, eddy covariance towers, and airborne campaigns were used to constrain the <span class="hlt">Community</span> Land <span class="hlt">Model</span> CLM4.5 simulated terrestrial CO<sub>2</sub> exchange at a high spatial and temporal resolution (1/24°, 3-hourly). To balance aggregation errors and the degrees of freedom in the inverse <span class="hlt">modeling</span> system, we applied an unsupervised clustering approach for the spatial structuring of our <span class="hlt">model</span> domain. Data from flight campaigns were used to quantify the uncertainty introduced by the Lagrangian particle dispersion <span class="hlt">model</span> that was applied for the inversions. The average annual statewide net ecosystem productivity (NEP) was increased by 32% to 29.7 TgC per year by assimilating the tropospheric mixing ratio data. The associated uncertainty was decreased by 28.4% to 29%, on average over the entire Oregon <span class="hlt">model</span> domain with the lowest uncertainties of 11% in western Oregon. The largest differences between posterior and prior CO<sub>2</sub> fluxes were found for the Coast Range ecoregion of Oregon that also exhibits the highest availability of <span class="hlt">atmospheric</span> observations and associated footprints. In this area, covered by highly productive Douglas-fir forest, the differences between the prior and posterior estimate of NEP averaged 3.84 TgC per year during the study period from 2012 through 2014.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A33B0213L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A33B0213L"><span>Held-Suarez simulations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Spectral Element (CAM-SE) dynamical core: a detailed global axial angular momentum analysis using Eulerian and Floating Lagrangian vertical coordinates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lauritzen, P. H.; Bacmeister, J. T.; Dubos, T.; Lebonnois, S.; Taylor, M.</p> <p>2013-12-01</p> <p>Conservation of Axial Angular Momentum (AAM) is a critical component of global general circulation <span class="hlt">models</span>. For planets such as Venus and Titan super-rotation comes about through small imbalances in surface sources/sinks of AAM and are therefore susceptible to non-conservation errors in the dynamical core. In Earth's <span class="hlt">atmosphere</span> the physical sources/sinks of AAM (e.g., resolved and parameterized mountain torques) are large so the lack of AAM may be less apparent. Nonetheless AAM conservation affects important phenomena such as the Quasi-Biennial Oscillation (QBO). In this paper a detailed analysis of the global AAM conservation properties of NCAR's <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Spectral Element (CAM-SE) dynamical core under Held-Suarez forcing is presented. It is shown that the spurious sources/sinks of AAM in CAM-SE are three orders of magnitude smaller than the parameterized (physical) sources/sinks. The effect on AAM conservation by changing various numerical aspects of the dynamical core (e.g., different vertical coordinates, reduced formal order of accuracy, increased dissipation and decreased divergence damping) is investigated. In particular it is noted that changing from Eulerian to Lagrangian vertical coordinates does not alter the excellent global AAM conservation properties of CAM-SE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JAMES...6..129L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JAMES...6..129L"><span>Held-Suarez simulations with the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Spectral Element (CAM-SE) dynamical core: A global axial angular momentum analysis using Eulerian and floating Lagrangian vertical coordinates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lauritzen, Peter H.; Bacmeister, Julio T.; Dubos, Thomas; Lebonnois, Sébastien; Taylor, Mark A.</p> <p>2014-03-01</p> <p>In this paper, an analysis of the global AAM conservation properties of NCAR's <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> Spectral Element (CAM-SE) dynamical core under Held-Suarez forcing is presented. It is shown that the spurious sources/sinks of AAM in CAM-SE are 3 orders of magnitude smaller than the parameterized (physical) sources/sinks. The effect on AAM conservation by changing various numerical aspects of the dynamical core (e.g., different vertical coordinates, reduced formal order of accuracy, increased dissipation, and decreased divergence damping) is investigated. In particular, it is noted that changing from Eulerian (hybrid-sigma) to floating Lagrangian vertical coordinates does not alter the global AAM conservation properties of CAM-SE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=133703&keyword=chesapeake+AND+bay+AND+pollution&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=133703&keyword=chesapeake+AND+bay+AND+pollution&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span><span class="hlt">ATMOSPHERIC</span> DEPOSITION <span class="hlt">MODELING</span> AND MONITORING OF NUTRIENTS</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This talk presents an overview of the capabilities and roles that regional <span class="hlt">atmospheric</span> deposition <span class="hlt">models</span> can play with respect to multi-media environmental problems. The focus is on nutrient deposition (nitrogen). <span class="hlt">Atmospheric</span> deposition of nitrogen is an important contributor to...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=133703&keyword=team+AND+roles+AND+work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=84621819&CFTOKEN=96865302','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=133703&keyword=team+AND+roles+AND+work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=84621819&CFTOKEN=96865302"><span><span class="hlt">ATMOSPHERIC</span> DEPOSITION <span class="hlt">MODELING</span> AND MONITORING OF NUTRIENTS</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This talk presents an overview of the capabilities and roles that regional <span class="hlt">atmospheric</span> deposition <span class="hlt">models</span> can play with respect to multi-media environmental problems. The focus is on nutrient deposition (nitrogen). <span class="hlt">Atmospheric</span> deposition of nitrogen is an important contributor to...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730055079&hterms=meteorological+calculation+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmeteorological%2Bcalculation%2Bmodel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730055079&hterms=meteorological+calculation+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmeteorological%2Bcalculation%2Bmodel"><span><span class="hlt">Atmospheric</span> <span class="hlt">model</span> for correction of spacecraft data.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Turner, R. E.; Spencer, M. M.</p> <p>1973-01-01</p> <p>Description of a radiative transfer <span class="hlt">model</span> which has been used to correct Apollo photographic imagery for degradation arising from <span class="hlt">atmospheric</span> scattering. The <span class="hlt">model</span> was tested using aircraft scanner data, and an extrapolation was then made to spacecraft altitudes. Using standard meteorological data for the region of interest, it is possible to determine transmittance, path radiance, and total radiance from calculations made with the multiple scattering <span class="hlt">atmospheric</span> <span class="hlt">model</span>. Simple algorithms are presented which allow potential users of spacecraft sensor data to correct imagery for the deleterious effects due to the scattering of radiation under clear or hazy <span class="hlt">atmospheric</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009SPIE.7304E..0HH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009SPIE.7304E..0HH"><span><span class="hlt">Modeling</span> the <span class="hlt">atmospheric</span> chemistry of TICs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Henley, Michael V.; Burns, Douglas S.; Chynwat, Veeradej; Moore, William; Plitz, Angela; Rottmann, Shawn; Hearn, John</p> <p>2009-05-01</p> <p>An <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span> that describes the behavior and disposition of environmentally hazardous compounds discharged into the <span class="hlt">atmosphere</span> was coupled with the transport and diffusion <span class="hlt">model</span>, SCIPUFF. The <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span> was developed by reducing a detailed <span class="hlt">atmospheric</span> chemistry mechanism to a simple empirical effective degradation rate term (keff) that is a function of important meteorological parameters such as solar flux, temperature, and cloud cover. Empirically derived keff functions that describe the degradation of target toxic industrial chemicals (TICs) were derived by statistically analyzing data generated from the detailed chemistry mechanism run over a wide range of (typical) <span class="hlt">atmospheric</span> conditions. To assess and identify areas to improve the developed <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span>, sensitivity and uncertainty analyses were performed to (1) quantify the sensitivity of the <span class="hlt">model</span> output (TIC concentrations) with respect to changes in the input parameters and (2) improve, where necessary, the quality of the input data based on sensitivity results. The <span class="hlt">model</span> predictions were evaluated against experimental data. Chamber data were used to remove the complexities of dispersion in the <span class="hlt">atmosphere</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA111632','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA111632"><span>Geophysical Plasmas and <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1982-01-01</p> <p>0-AIII 639 SCIENCE APLICATIONS INC MCLEAN VA pis 4/1 GEOPHYSICAL. PLASMAS AND <span class="hlt">ATMOSPHERIC</span> NOOCLIMG. (UI JAN 82 1 HMNh, J1 APIUZESE, S SNECH?. V CHAO...implied by delta functions. The eigenfunc- R 1_c 2 tion is continuous at each boundary and vanishes both at * web 2y V 4 -R1,)1r r<R4 , r -0 and r-R</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20060004756','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20060004756"><span>GLOBAL REFERENCE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODELS</span> FOR AEROASSIST APPLICATIONS</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Duvall, Aleta; Justus, C. G.; Keller, Vernon W.</p> <p>2005-01-01</p> <p>Aeroassist is a broad category of advanced transportation technology encompassing aerocapture, aerobraking, aeroentry, precision landing, hazard detection and avoidance, and aerogravity assist. The eight destinations in the Solar System with sufficient <span class="hlt">atmosphere</span> to enable aeroassist technology are Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Saturn's moon Titan. Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for five of these targets - Earth, Mars, Titan, Neptune, and Venus - have been developed at NASA's Marshall Space Flight Center. These <span class="hlt">models</span> are useful as tools in mission planning and systems analysis studies associated with aeroassist applications. The series of <span class="hlt">models</span> is collectively named the Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> or GRAM series. An important capability of all the <span class="hlt">models</span> in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analysis in developing guidance, navigation and control algorithms, for aerothermal design, and for other applications sensitive to <span class="hlt">atmospheric</span> variability. Recent example applications are discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810049200&hterms=bionics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dbionics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810049200&hterms=bionics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dbionics"><span>Combined eye-<span class="hlt">atmosphere</span> visibility <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaufman, Y. J.</p> <p>1981-01-01</p> <p>Existing <span class="hlt">models</span> of the optical characteristics of the eye are combined with a recent <span class="hlt">model</span> of optical characteristics of the <span class="hlt">atmosphere</span> given by its modulation transfer function. This combination results in the combined eye-<span class="hlt">atmosphere</span> performance given by the product of their modulation transfer functions. An application for the calculation of visibility thresholds in the case of a two-halves field is given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..494N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..494N"><span>An online educational <span class="hlt">atmospheric</span> global circulation <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Navarro, T.; Schott, C.; Forget, F.</p> <p>2015-10-01</p> <p>As part of online courses on exoplanets of Observatoire de Paris, an online tool designed to vizualise outputs of the Laboratoire de Métérologie Dynamique (LMD) Global Circulation <span class="hlt">Model</span> (GCM) for various <span class="hlt">atmospheric</span> circulation regimes has been developed. It includes the possibility for students to visualize 1D and 2D plots along with animations of <span class="hlt">atmospheric</span> quantities such as temperature, winds, surface pressure, mass flux, etc... from a state-of-the-art <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810049200&hterms=bionic+eye&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dbionic%2Beye','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810049200&hterms=bionic+eye&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dbionic%2Beye"><span>Combined eye-<span class="hlt">atmosphere</span> visibility <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kaufman, Y. J.</p> <p>1981-01-01</p> <p>Existing <span class="hlt">models</span> of the optical characteristics of the eye are combined with a recent <span class="hlt">model</span> of optical characteristics of the <span class="hlt">atmosphere</span> given by its modulation transfer function. This combination results in the combined eye-<span class="hlt">atmosphere</span> performance given by the product of their modulation transfer functions. An application for the calculation of visibility thresholds in the case of a two-halves field is given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.P31B2068H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.P31B2068H"><span><span class="hlt">Modeling</span> Callisto's Ionosphere: Insight Into Callisto's <span class="hlt">Atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hartkorn, O. A.; Saur, J.; Strobel, D. F.</p> <p>2015-12-01</p> <p>We develop a kinetic <span class="hlt">model</span> of the ionosphere of Jupiter's moon Callisto within a prescribed neutral <span class="hlt">atmosphere</span> composed of O2 and CO2. We calculate the electron energy distribution as a function of space by solving the Boltzmann equation and assuming a stationary balance between local sources and sinks of electrons and electron energy. Electron transport within the ionosphere is neglected, whereas we approximate the electron transport out of the ionosphere into the Jovian magnetosphere. Photoionization is believed to be the major electron source within Callisto's <span class="hlt">atmosphere</span>. Therefore, we calculate the energy dependent photoelectron spectrum as source term of the Boltzmann equation. The resulting Boltzmann equation is solved rigorously delivering electron distribution functions at every point of Callisto's <span class="hlt">atmosphere</span>. From these distribution functions, we calculate electron densities and electron impact generated UV emissions from Callisto's <span class="hlt">atmosphere</span>. The calculated electron densities and UV emissions are compared with observations of the Galileo spacecraft [Kliore et al., 2002] and the Hubble Space Telescope [Cunningham et al., 2015]. Based on these comparisons, we test a physically motivated <span class="hlt">atmosphere</span> <span class="hlt">model</span> including asymmetries that depend on Callisto's orbital phase, similar to Europa's <span class="hlt">atmosphere</span> [Plainaki et al., 2013]. As a result, we gain knowledge about Callisto's <span class="hlt">atmospheric</span> density and its <span class="hlt">atmospheric</span> asymmetries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17749730','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17749730"><span><span class="hlt">Atmosphere</span> of Mars: Mariner IV <span class="hlt">Models</span> Compared.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fjeldbo, G; Fjeldbo, W C; Eshleman, V R</p> <p>1966-09-23</p> <p>Three classes of <span class="hlt">models</span> for the <span class="hlt">atmosphere</span> of Mars differ in identifying the main ionospheric layer measured by Mariner IV as being analogous to a terrestrial F(2), F(1), or E layer. At an altitude of several hundred kilometers, the relative <span class="hlt">atmospheric</span> mass densities for these <span class="hlt">models</span> (in the order named) are approximately 1, 10(2), and 10(4), and the temperatures are roughly 100 degrees , 200 degrees , and 400 degrees K. Theory and observation are in best agreement for an F, s <span class="hlt">model</span>, for which photodissociation of CO(2), and diffusive separation result in an atomic-oxygen upper <span class="hlt">atmosphere</span>, with O(+) being the principal ion in the isothermal topside of the ionosphere. The mesopause temperature minimum would be at or below the freezing point of CO(2), and dry ice particles would be expected to form. However, an F(1) <span class="hlt">model</span>, with molecular ions in a mixed and warmer upper <span class="hlt">atmosphere</span>, might result if photodissociation and diffusive separation are markedly less than would be expected from analogy with Earth's upper <span class="hlt">atmosphere</span>. The E <span class="hlt">model</span> proposed by Chamberlain and McElroy appears very unlikely; it is not compatible with the measured ionization profile unless rather unlikely assumptions are made about the values, and changes with height, of the effective recombination coefficient and the average ion mass. Moreover our theoretical heat-budget computations for the <span class="hlt">atmospheric</span> region probed by Mariner IV indicate markedly lower temperatures and temperature gradients than were obtained for the E <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890011217','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890011217"><span>An assessment <span class="hlt">model</span> for <span class="hlt">atmospheric</span> composition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Prather, Michael J. (Editor)</p> <p>1988-01-01</p> <p>Predicting future perturbations to global air quality and climate requires, as a prerequisite, prognostic <span class="hlt">models</span> for the composition of the Earth's <span class="hlt">atmosphere</span>. Such assessment <span class="hlt">models</span> are needed to evaluate the impact on our environment of different social choices that affect emissions of the photochemically and radiatively important trace gases. Our presentation here of a prototype assessment <span class="hlt">model</span> is intended to encourage public scientific discussions of the necessary components of the <span class="hlt">model</span> and their interactions, with the recognition that <span class="hlt">models</span> similar to this will likely be used by the Environmental Protection Agency and other regulatory agencies in order to assess the effect of changes in <span class="hlt">atmospheric</span> composition on climate over the next century.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.C41B0965M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.C41B0965M"><span>Scale Dependence Between Hydrologic and <span class="hlt">Atmospheric</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morehead, M. D.; Marks, D.; Winstral, A.</p> <p>2003-12-01</p> <p>A disparity tends to exist between the scales simulated by <span class="hlt">atmospheric</span> <span class="hlt">models</span> intended as input for hydrologic <span class="hlt">modeling</span> and those at which hydrologic <span class="hlt">modelers</span> simulate processes especially snow accumulation and depletion in mountainous terrain. Two different <span class="hlt">models</span> are used to generate input <span class="hlt">atmospheric</span> data at various scales to drive a snow hydrology <span class="hlt">model</span> and test the sensitivity of the snow processes at various forcing scales. One of the input <span class="hlt">atmospheric</span> <span class="hlt">models</span> is the nested grid <span class="hlt">atmospheric</span> <span class="hlt">model</span>, RAMS, developed at Colorado State University. The second input <span class="hlt">model</span> uses IPW (Image Processing Workbench) to distribute measured climatic variables over complex landscapes. The snow energy balance <span class="hlt">model</span> is the grid based ISNOBAL. The simulations are performed in the Reynolds Creek Experimental Watershed (RCEW) in the Owyhee Mountains of South-Western Idaho. RCEW is well instrumented with distributed rain gauges, meteorological sites, snow pillows, and discharge weirs. A Rain-on-Snow flooding event is used for the simulations which occurred during the end of December 1996 and the beginning of January 1997. The analysis is showing that <span class="hlt">atmospheric</span> grids on the order of tens of kilometers miss much of the detailed <span class="hlt">atmospheric</span> dynamics controlling snowfall in the complex terrain of the Owyhee Mountains and lead to incorrect hydrologic results if simplistic downscaling techniques are used. The detailed variability in the precipitation gauges is on the order of a kilometer or less and the snow pack variability is on even smaller scales. It is hypothesized that <span class="hlt">atmospheric</span> forcing need to be <span class="hlt">modeled</span> down to scales on the order of 1 kilometer and then redistributed by wind effects to accurately depict the complex conditions in mountainous terrain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DPS....4741607H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DPS....4741607H"><span>Chemical uncertainties in <span class="hlt">modeling</span> hot Jupiters <span class="hlt">atmospheres</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hebrard, Eric; Domagal-Goldman, Shawn</p> <p>2015-11-01</p> <p>Most predictions and interpretations of observations in beyond our Solar System have occurred through the use of 1D photo-thermo-chemical <span class="hlt">models</span>. Their predicted <span class="hlt">atmospheric</span> compositions are highly dependent on <span class="hlt">model</span> parameters. Chemical reactions are based on empirical parameters that must be known at temperatures ranging from 100 K to above 2500 K and at pressures from millibars to hundreds of bars. Obtained from experiments, calculations and educated-guessed estimations, these parameters are always evaluated with substantial uncertainties. However, although of practical use, few <span class="hlt">models</span> of exoplanetary <span class="hlt">atmospheres</span> have considered these underlying chemical uncertainties and their consequences. Recent progress has been made recently that allow us to (1) evaluate the accuracy and precision of 1D <span class="hlt">models</span> of planetary <span class="hlt">atmospheres</span>, with quantifiable uncertainties on their predictions for the <span class="hlt">atmospheric</span> composition and associated spectral features, (2) identify the ‘key parameters’ that contribute the most to the <span class="hlt">models</span> predictivity and should therefore require further experimental or theoretical analysis, (3) reduce and optimize complex chemical networks for their inclusion in multidimensional <span class="hlt">atmospheric</span> <span class="hlt">models</span>.First, a global sampling approach based on low discrepancy sequences has been applied in order to propose error bars on simulations of the <span class="hlt">atmospheres</span> HD 209458b and HD 189733b, using a detailed kinetic <span class="hlt">model</span> derived from applied combustion <span class="hlt">models</span> that was methodically validated over a range of temperatures and pressures typical for these hot Jupiters. A two-parameters temperature-dependent uncertainty factor has been assigned to each considered rate constant. Second, a global sensitivity approach based on high dimensional <span class="hlt">model</span> representations (HDMR) has been applied in order to identify those reactions which make the largest contributions to the overall uncertainty of the simulated results. The HDMR analysis has been restricted to the most important</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830013406','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830013406"><span><span class="hlt">Atmospheric</span> radiation <span class="hlt">model</span> for water surfaces</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Turner, R. E.; Gaskill, D. W.; Lierzer, J. R.</p> <p>1982-01-01</p> <p>An <span class="hlt">atmospheric</span> correction <span class="hlt">model</span> was extended to account for various <span class="hlt">atmospheric</span> radiation components in remotely sensed data. Components such as the <span class="hlt">atmospheric</span> path radiance which results from singly scattered sky radiation specularly reflected by the water surface are considered. A component which is referred to as the virtual Sun path radiance, i.e. the singly scattered path radiance which results from the solar radiation which is specularly reflected by the water surface is also considered. These <span class="hlt">atmospheric</span> radiation components are coded into a computer program for the analysis of multispectral remote sensor data over the Great Lakes of the United States. The user must know certain parameters, such as the visibility or spectral optical thickness of the <span class="hlt">atmosphere</span> and the geometry of the sensor with respect to the Sun and the target elements under investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=154810&keyword=static+AND+dynamic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78001885&CFTOKEN=57287486','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=154810&keyword=static+AND+dynamic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78001885&CFTOKEN=57287486"><span>THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span> EVALUATION TOOL</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This poster describes a <span class="hlt">model</span> evaluation tool that is currently being developed and applied for meteorological and air quality <span class="hlt">model</span> evaluation. The poster outlines the framework and provides examples of statistical evaluations that can be performed with the <span class="hlt">model</span> evaluation tool...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=154810&keyword=Model+AND+Transport+AND+Research+AND+Operational&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=154810&keyword=Model+AND+Transport+AND+Research+AND+Operational&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span> EVALUATION TOOL</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This poster describes a <span class="hlt">model</span> evaluation tool that is currently being developed and applied for meteorological and air quality <span class="hlt">model</span> evaluation. The poster outlines the framework and provides examples of statistical evaluations that can be performed with the <span class="hlt">model</span> evaluation tool...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=161804&keyword=post+AND+implementation+AND+model&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=84826869&CFTOKEN=63921200','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=161804&keyword=post+AND+implementation+AND+model&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=84826869&CFTOKEN=63921200"><span>REGIONAL-SCALE <span class="hlt">ATMOSPHERIC</span> MERCURY <span class="hlt">MODELING</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This PowerPoint presentation gives a short synopsis of the state of the science of <span class="hlt">atmospheric</span> mercury <span class="hlt">modeling</span>, including a description of recent publications of <span class="hlt">model</span> codes by EPA, a description of a recent mercury <span class="hlt">model</span> intercomparison study, and a description of a synthesis p...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=139233&keyword=state+AND+space+AND+models&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=139233&keyword=state+AND+space+AND+models&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span> EVALUATION (AMET): METEOROLOGY MODULE</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>An <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Evaluation Tool (AMET), composed of meteorological and air quality components, is being developed to examine the error and uncertainty in the <span class="hlt">model</span> simulations. AMET matches observations with the corresponding <span class="hlt">model</span>-estimated values in space and time, and the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMIN41B1497C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMIN41B1497C"><span>VIIRS <span class="hlt">Atmospheric</span> Products in the <span class="hlt">Community</span> Satellite Processing Package (CSPP)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cureton, G. P.; Gumley, L.; Mindock, S.; Martin, G.; Garcia, R. K.; Strabala, K.</p> <p>2012-12-01</p> <p>The Cooperative Institute for Meteorological Satellite Studies (CIMSS) has a long history of supporting the Direct Broadcast (DB) <span class="hlt">community</span> for various sensors, recently with the International MODIS/AIRS Processing Package (IMAPP) for the NASA EOS polar orbiters Terra and Aqua. CIMSS has continued this effort into the NPP/JPSS (previously NPOESS) era with the development of the <span class="hlt">Community</span> Satellite Processing Package (CSPP), supporting the VIIRS, CrIS and ATMS sensors on the Suomi National Polar-orbiting Partnership (Suomi NPP) spacecraft. In time it is intended that CSPP will support GOES-R, JPSS and other geostationary and polar orbiting platforms. Here we focus on the implementation and usage of the Visible Infrared Imaging Radiometer Suite (VIIRS) <span class="hlt">atmospheric</span> product sub-packages within CSPP, which are based on the Interface Data Processing Segment (IDPS) code as implemented by Raytheon in the Algorithm Development Library (ADL). The VIIRS <span class="hlt">atmospheric</span> algorithms available in CSPP include the Cloud Mask, Active Fires, Cloud Optical Properties, Cloud Top Parameters, and the Aerosol Optical Thickness algorithms. Each ADL sub-package consists of a binary executable and a series of configuration XML files. A series of python scripts handle ancillary data retrieval and preparation for ingest into ADL, manage algorithm execution, and provide a variety of execution options which are of utility in operational and algorithm development settings. Examples of these options, applied to operational and direct-broadcast VIIRS SDR data, are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28400020','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28400020"><span>Bacterial <span class="hlt">communities</span> of fresh goat meat packaged in modified <span class="hlt">atmosphere</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carrizosa, Elia; Benito, María José; Ruiz-Moyano, Santiago; Hernández, Alejandro; Villalobos, Maria Del Carmen; Martín, Alberto; Córdoba, María de Guía</p> <p>2017-08-01</p> <p>The objective of this work was to study the growth and development of fortuitous flora and food pathogens in fresh goat meat packaged under modified <span class="hlt">atmospheres</span> containing two different concentrations of CO2. Meat samples were stored at 10 °C under two different modified-<span class="hlt">atmosphere</span> packing (MAP) conditions: treatment A had 45% CO2 + 20% O2 + 35% N2 and treatment B had 20% CO2 + 55% O2 + 25% N2. During 14 days of storage, counts of each bacterial group and dominant species identification by 16S rRNA gene sequencing were performed to determine the microbial diversity present. The MAP condition used for treatment A was a more effective gas mixture for increasing the shelf life of fresh goat meat, significantly reducing the total number of viable bacteria and enterobacteria counts. Members of the Enterobacteriaceae family were the most common contaminants, although Hafnia alvei was dominant in treatment A and Serratia proteamaculans in treatment B. Identification studies at the species level showed that different microorganisms develop under different storage conditions, reflecting the importance of gas composition in the modified <span class="hlt">atmosphere</span> on the bacterial <span class="hlt">community</span>. This work provides new insights into the microbial changes of goat meat storage under different MAP conditions, which will be beneficial for the meat industry. Copyright © 2017 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900007073','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900007073"><span>New <span class="hlt">Atmospheric</span> Turbulence <span class="hlt">Model</span> for Shuttle Applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Campbell, C. W.; Doubleday, M. K.; Johnson, D. L.</p> <p>1990-01-01</p> <p>An updated NASA <span class="hlt">atmospheric</span> turbulence <span class="hlt">model</span>, from 0 to 200 km altitude, which was developed to be more realistic and less conservative when applied to space shuttle reentry engineering simulation studies involving control system fuel expenditures is presented. The prior <span class="hlt">model</span> used extreme turbulence (3 sigma) for all altitudes, whereas in reality severe turbulence is patchy within quiescent <span class="hlt">atmospheric</span> zones. The updated turublence <span class="hlt">model</span> presented is designed to be more realistic. The prior turbulence statistics (sigma and L) were updated and were <span class="hlt">modeled</span> accordingly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA171688','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA171688"><span>Geophysical Plasmas and <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1986-07-01</p> <p>collisionless topside and collisional bottomside ionosphere using a <span class="hlt">model</span> Fokker - Planck collision operator for ion-ion collisions, (b) Current driven...Report 5656 (1985). Currently a Fokker - Planck <span class="hlt">model</span> is used to represent the ion-ion collision and applied to study the current driven ion cyclotron...are given in Appendix G (Satyanarayana, P., et. al., Phys. Fluids, 29 (1986)). Currently, the Fokker - Planck <span class="hlt">model</span> used in 2.1 is being applied to show</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870027233&hterms=Infrared+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DInfrared%2Bradiation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870027233&hterms=Infrared+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DInfrared%2Bradiation"><span>Infrared radiation <span class="hlt">models</span> for <span class="hlt">atmospheric</span> methane</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cess, R. D.; Kratz, D. P.; Caldwell, J.; Kim, S. J.</p> <p>1986-01-01</p> <p>Mutually consistent line-by-line, narrow-band and broad-band infrared radiation <span class="hlt">models</span> are presented for methane, a potentially important anthropogenic trace gas within the <span class="hlt">atmosphere</span>. Comparisons of the <span class="hlt">modeled</span> band absorptances with existing laboratory data produce the best agreement when, within the band <span class="hlt">models</span>, spurious band intensities are used which are consistent with the respective laboratory data sets, but which are not consistent with current knowledge concerning the intensity of the infrared fundamental band of methane. This emphasizes the need for improved laboratory band absorptance measurements. Since, when applied to <span class="hlt">atmospheric</span> radiation calculations, the line-by-line <span class="hlt">model</span> does not require the use of scaling approximations, the mutual consistency of the band <span class="hlt">models</span> provides a means of appraising the accuracy of scaling procedures. It is shown that Curtis-Godson narrow-band and Chan-Tien broad-band scaling provide accurate means of accounting for <span class="hlt">atmospheric</span> temperature and pressure variations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2890735','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2890735"><span>Shifting carbon flow from roots into associated microbial <span class="hlt">communities</span> in response to elevated <span class="hlt">atmospheric</span> CO2</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Drigo, Barbara; Pijl, Agata S.; Duyts, Henk; Kielak, Anna M.; Gamper, Hannes A.; Houtekamer, Marco J.; Boschker, Henricus T. S.; Bodelier, Paul L. E.; Whiteley, Andrew S.; van Veen, Johannes A.; Kowalchuk, George A.</p> <p>2010-01-01</p> <p>Rising <span class="hlt">atmospheric</span> CO2 levels are predicted to have major consequences on carbon cycling and the functioning of terrestrial ecosystems. Increased photosynthetic activity is expected, especially for C-3 plants, thereby influencing vegetation dynamics; however, little is known about the path of fixed carbon into soil-borne <span class="hlt">communities</span> and resulting feedbacks on ecosystem function. Here, we examine how arbuscular mycorrhizal fungi (AMF) act as a major conduit in the transfer of carbon between plants and soil and how elevated <span class="hlt">atmospheric</span> CO2 modulates the belowground translocation pathway of plant-fixed carbon. Shifts in active AMF species under elevated <span class="hlt">atmospheric</span> CO2 conditions are coupled to changes within active rhizosphere bacterial and fungal <span class="hlt">communities</span>. Thus, as opposed to simply increasing the activity of soil-borne microbes through enhanced rhizodeposition, elevated <span class="hlt">atmospheric</span> CO2 clearly evokes the emergence of distinct opportunistic plant-associated microbial <span class="hlt">communities</span>. Analyses involving RNA-based stable isotope probing, neutral/phosphate lipid fatty acids stable isotope probing, <span class="hlt">community</span> fingerprinting, and real-time PCR allowed us to trace plant-fixed carbon to the affected soil-borne microorganisms. Based on our data, we present a conceptual <span class="hlt">model</span> in which plant-assimilated carbon is rapidly transferred to AMF, followed by a slower release from AMF to the bacterial and fungal populations well-adapted to the prevailing (myco-)rhizosphere conditions. This <span class="hlt">model</span> provides a general framework for reappraising carbon-flow paths in soils, facilitating predictions of future interactions between rising <span class="hlt">atmospheric</span> CO2 concentrations and terrestrial ecosystems. PMID:20534474</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.474..198S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.474..198S"><span>A <span class="hlt">model</span> of the primordial lunar <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saxena, Prabal; Elkins-Tanton, Lindy; Petro, Noah; Mandell, Avi</p> <p>2017-09-01</p> <p>We create the first quantitative <span class="hlt">model</span> for the early lunar <span class="hlt">atmosphere</span>, coupled with a magma ocean crystallization <span class="hlt">model</span>. Immediately after formation, the moon's surface was subject to a radiative environment that included contributions from the early Sun, a post-impact Earth that radiated like a mid-type M dwarf star, and a cooling global magma ocean. This radiative environment resulted in a largely Earth-side <span class="hlt">atmosphere</span> on the Moon, ranging from ∼104 to ∼102 pascals, composed of heavy volatiles (Na and SiO). This <span class="hlt">atmosphere</span> persisted through lid formation and was additionally characterized by supersonic winds that transported significant quantities of moderate volatiles and likely generated magma ocean waves. The existence of this <span class="hlt">atmosphere</span> may have influenced the distribution of some moderate volatiles and created temperature asymmetries which influenced ocean flow and cooling. Such asymmetries may characterize young, tidally locked rocky bodies with global magma oceans and subject to intense irradiation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMIN11D1067S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMIN11D1067S"><span>Processing <span class="hlt">Community</span> <span class="hlt">Model</span> Output: An Approach to <span class="hlt">Community</span> Accessibility (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shea, D.; Haley, M.</p> <p>2009-12-01</p> <p>The <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> (CCSM) is a fully-coupled, global climate <span class="hlt">model</span> that provides state-of-the-art computer simulations of the Earth's past, present, and future climate states. The major components are <span class="hlt">models</span> of the <span class="hlt">atmosphere</span>, land, ocean and sea-ice. In both the development and production phases, the <span class="hlt">model</span> output must be analyzed by developers and a diverse <span class="hlt">community</span> of climate researchers. To facilitate <span class="hlt">community</span> accessibility to the data, two decisions were made: (a) each component <span class="hlt">model</span> would archive results in netCDF format (b) a supported and portable software analysis tool would be made available. NetCDF (network Common Data Format) is a set of software libraries and machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data. It is available for a large variety of programming languages and many software tools can be used to manipulate and display data in netCDF files. After a 'competition' which included commercial and public domain software products, the NCAR Command Language (NCL) was selected as the 'official' analysis tool for CCSM analysis. NCL is a portable, supported software product for file handling, computations and high-quality graphics. Subsequently, a development team consisting of software engineers and scientists was created to collaborate to develop a tool capable of addressing the evolving and diverse needs of the climate <span class="hlt">modeling</span> and observational research <span class="hlt">communities</span>. The process of educating the user <span class="hlt">community</span> about netCDF and NCL includes hundreds of online examples and numerous 'hands-on' workshops. The latter are held 3-to-5 times per year at NCAR and external locations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870011246','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870011246"><span>Users of middle <span class="hlt">atmosphere</span> <span class="hlt">models</span> remarks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gamble, Joe</p> <p>1987-01-01</p> <p>The procedure followed for shuttle operations is to calculate descent trajectories for each potential shuttle landing site using the Global Reference <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (GRAM) to interactively compute density along the flight path 100 times to bound the statistics. The purpose is to analyze the flight dynamics, along with calculations of heat loads during reentry. The analysis program makes use of the modified version of the Jacchia-70 <span class="hlt">atmosphere</span>, which includes He bulges over the poles and seasonal latitude variations at lower altitudes. For the troposphere, the 4-D <span class="hlt">Model</span> is used up to 20 km, Groves from 30 km up to 90 km. It is extrapolated over the globe and faired into the Jacchia <span class="hlt">atmosphere</span> between 90 and 115 km. Since data on the Southern Hemisphere was lacking, what was done was that the data was flipped over and lagged 6 months. Sometimes when winds are calculated from pressure data in the <span class="hlt">model</span> there appear to be discontinuities. <span class="hlt">Modelers</span> indicated that the GRAM was not designed to produce winds, but good wind data is needed for the landing phase of shuttle operations. Use of <span class="hlt">atmospheric</span> <span class="hlt">models</span> during reentry is one application where it is obvious that a single integrated <span class="hlt">atmosphere</span> <span class="hlt">model</span> is required.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900017447','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900017447"><span>Chemical kinetics and <span class="hlt">modeling</span> of planetary <span class="hlt">atmospheres</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yung, Yuk L.</p> <p>1990-01-01</p> <p>A unified overview is presented for chemical kinetics and chemical <span class="hlt">modeling</span> in planetary <span class="hlt">atmospheres</span>. The recent major advances in the understanding of the chemistry of the terrestrial <span class="hlt">atmosphere</span> make the study of planets more interesting and relevant. A deeper understanding suggests that the important chemical cycles have a universal character that connects the different planets and ultimately link together the origin and evolution of the solar system. The completeness (or incompleteness) of the data base for chemical kinetics in planetary <span class="hlt">atmospheres</span> will always be judged by comparison with that for the terrestrial <span class="hlt">atmosphere</span>. In the latter case, the chemistry of H, O, N, and Cl species is well understood. S chemistry is poorly understood. In the <span class="hlt">atmospheres</span> of Jovian planets and Titan, the C-H chemistry of simple species (containing 2 or less C atoms) is fairly well understood. The chemistry of higher hydrocarbons and the C-N, P-N chemistry is much less understood. In the <span class="hlt">atmosphere</span> of Venus, the dominant chemistry is that of chlorine and sulfur, and very little is known about C1-S coupled chemistry. A new frontier for chemical kinetics both in the Earth and planetary <span class="hlt">atmospheres</span> is the study of heterogeneous reactions. The formation of the ozone hole on Earth, the ubiquitous photochemical haze on Venus and in the Jovian planets and Titan all testify to the importance of heterogeneous reactions. It remains a challenge to connect the gas phase chemistry to the production of aerosols.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760003870&hterms=karp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dkarp','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760003870&hterms=karp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dkarp"><span>Hydrodynamic <span class="hlt">models</span> of a Cepheid <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Karp, A. H.</p> <p>1975-01-01</p> <p>Instead of computing a large number of coarsely zoned hydrodynamic <span class="hlt">models</span> covering the entire <span class="hlt">atmospheric</span> instability strip, the author computed a single <span class="hlt">model</span> as well as computer limitations allow. The implicit hydrodynamic code of Kutter and Sparks was modified to include radiative transfer effects in optically thin zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=65804&keyword=mercury+AND+compound&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90750284&CFTOKEN=12033257','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=65804&keyword=mercury+AND+compound&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90750284&CFTOKEN=12033257"><span><span class="hlt">ATMOSPHERIC</span> MERCURY SIMULATION USING THE CMAQ <span class="hlt">MODEL</span>: FORMULATION DESCRIPTION AND ANALYSIS OF WET DEPOSITION RESULTS</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">modeling</span> system has recently been adapted to simulate the emission, transport, transformation and deposition of <span class="hlt">atmospheric</span> mercury in three distinct forms; elemental mercury gas, reactive gaseous mercury, and particulate mercury. Emis...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982ApOpt..21.4381E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982ApOpt..21.4381E"><span>Radiative cooling computed for <span class="hlt">model</span> <span class="hlt">atmospheres</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eriksson, T. S.; Granqvist, C. G.</p> <p>1982-12-01</p> <p>The radiative cooling power and temperature drop of horizontal surfaces are evaluated on the basis of calculations of spectral radiance from <span class="hlt">model</span> <span class="hlt">atmospheres</span> representative of various climatic conditions. Calculations of <span class="hlt">atmospheric</span> radiance from the zenith and from off-zenith angles were performed with the LOWTRAN 5 <span class="hlt">atmospheric</span> transmittance/radiance computer code (Kneizys et al., 1980) for <span class="hlt">model</span> <span class="hlt">atmospheres</span> corresponding to the tropics, midlatitude summer, midlatitude winter, subarctic summer, subarctic winter and the 1962 U.S. standard <span class="hlt">atmosphere</span>. Comparison of the computed spectral radiance curves with the radiative fluxes from blackbody surfaces and ideal infrared-selective surfaces (having reflectance in the 8-13 micron range and unity reflectance elsewhere) at various ambient-surface temperature differences shows cooling powers to lie between 58 and 113 W/sq m at ambient temperature for a freely radiating surface, with maximum temperature differences of 11-21 C for a blackbody and 18-33 C for an infrared-selective surface. Both cooling powers and temperature differences were higher for surfaces exposed only to <span class="hlt">atmospheric</span> zenith radiance. In addition, water vapor content is found to affect strongly the radiative cooling, while ozone and aerosol contents had little effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880056655&hterms=Infrared+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DInfrared%2Bradiation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880056655&hterms=Infrared+radiation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DInfrared%2Bradiation"><span>Infrared radiation <span class="hlt">models</span> for <span class="hlt">atmospheric</span> ozone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kratz, David P.; Ces, Robert D.</p> <p>1988-01-01</p> <p>A hierarchy of line-by-line, narrow-band, and broadband infrared radiation <span class="hlt">models</span> are discussed for ozone, a radiatively important <span class="hlt">atmospheric</span> trace gas. It is shown that the narrow-band (Malkmus) <span class="hlt">model</span> is in near-precise agreement with the line-by-line <span class="hlt">model</span>, thus providing a means of testing narrow-band Curtis-Godson scaling, and it is found that this scaling procedure leads to errors in <span class="hlt">atmospheric</span> fluxes of up to 10 percent. Moreover, this is a direct consequence of the altitude dependence of the ozone mixing ratio. Somewhat greater flux errors arise with use of the broadband <span class="hlt">model</span>, due to both a lesser accuracy of the broadband scaling procedure and to inherent errors within the broadband <span class="hlt">model</span>, despite the fact that this <span class="hlt">model</span> has been tuned to the line-by-line <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880056655&hterms=ozone+infrared&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dozone%2Binfrared','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880056655&hterms=ozone+infrared&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dozone%2Binfrared"><span>Infrared radiation <span class="hlt">models</span> for <span class="hlt">atmospheric</span> ozone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kratz, David P.; Ces, Robert D.</p> <p>1988-01-01</p> <p>A hierarchy of line-by-line, narrow-band, and broadband infrared radiation <span class="hlt">models</span> are discussed for ozone, a radiatively important <span class="hlt">atmospheric</span> trace gas. It is shown that the narrow-band (Malkmus) <span class="hlt">model</span> is in near-precise agreement with the line-by-line <span class="hlt">model</span>, thus providing a means of testing narrow-band Curtis-Godson scaling, and it is found that this scaling procedure leads to errors in <span class="hlt">atmospheric</span> fluxes of up to 10 percent. Moreover, this is a direct consequence of the altitude dependence of the ozone mixing ratio. Somewhat greater flux errors arise with use of the broadband <span class="hlt">model</span>, due to both a lesser accuracy of the broadband scaling procedure and to inherent errors within the broadband <span class="hlt">model</span>, despite the fact that this <span class="hlt">model</span> has been tuned to the line-by-line <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA126341','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA126341"><span>Geophysical Plasmas and <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1983-02-01</p> <p>currently have limited our studies to a 2D <span class="hlt">model</span> corresponding to a detector an infinite distance away, and looking along the magnetic field. Later we...cloud smoothness and detector angle. Then, we plan to generalize to a 3D cloud to study off-angle (of the magnetic field) effects and parallax...THE "STABILIZATION" OF THE LOWER HYBRID- DRIFT INSTABILITY IN FINITE p PLASMAS ..... D-I Appendix E - FINITE WIDTH CURRENTS, MAGNETIC SHEAR AND THE</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850008016','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850008016"><span><span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> And Sensor Simulation (AMASS) study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parker, K. G.</p> <p>1984-01-01</p> <p>The capabilities of the <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> and sensor simulation (AMASS) system were studied in order to enhance them. This system is used in processing <span class="hlt">atmospheric</span> measurements which are utilized in the evaluation of sensor performance, conducting design-concept simulation studies, and also in the <span class="hlt">modeling</span> of the physical and dynamical nature of <span class="hlt">atmospheric</span> processes. The study tasks proposed in order to both enhance the AMASS system utilization and to integrate the AMASS system with other existing equipment to facilitate the analysis of data for <span class="hlt">modeling</span> and image processing are enumerated. The following array processors were evaluated for anticipated effectiveness and/or improvements in throughput by attachment of the device to the P-e: (1) Floating Point Systems AP-120B; (2) Floating Point Systems 5000; (3) CSP, Inc. MAP-400; (4) Analogic AP500; (5) Numerix MARS-432; and (6) Star Technologies, Inc. ST-100.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA026354','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA026354"><span>Workshop on <span class="hlt">Atmospheric</span> Transmission <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1975-12-01</p> <p>trans- mission <span class="hlt">modeling</span>. The workshop was divided into a morning rsession in which paper’s relating to the topic were pre- sented and an afternoon...a quantitative sense until Rosell’s work referenced above, Here it became clear that the work done by Johnson related the number of line pairs of a...needs to be adjusted according to the gaussian form shown in Fig. 2. Here the value of 50 percent probability is related to a normalized value of 1.0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040012991&hterms=importance+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dimportance%2Bwater','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040012991&hterms=importance+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dimportance%2Bwater"><span>Tagging Water Sources in <span class="hlt">Atmospheric</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bosilovich, M.</p> <p>2003-01-01</p> <p>Tagging of water sources in <span class="hlt">atmospheric</span> <span class="hlt">models</span> allows for quantitative diagnostics of how water is transported from its source region to its sink region. In this presentation, we review how this methodology is applied to global <span class="hlt">atmospheric</span> <span class="hlt">models</span>. We will present several applications of the methodology. In one example, the regional sources of water for the North American Monsoon system are evaluated by tagging the surface evaporation. In another example, the tagged water is used to quantify the global water cycling rate and residence time. We will also discuss the need for more research and the importance of these diagnostics in water cycle studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001RaSc...36.1385L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001RaSc...36.1385L"><span>Wideband <span class="hlt">model</span> of HF <span class="hlt">atmospheric</span> radio noise</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lemmon, John J.</p> <p>2001-01-01</p> <p>A <span class="hlt">model</span> of the waveform generated by high-frequency <span class="hlt">atmospheric</span> radio noise is presented. Cumulative probability distributions of the noise envelope are derived and shown to be in good agreement with a large database collected from a wide range of noise environments. The <span class="hlt">model</span> includes correlations in the waveforms that simulate the burst structure of measured <span class="hlt">atmospheric</span> noise. The bandwidth dependence of the voltage deviation parameter, which parameterizes the impulsiveness of the noise, shows behavior that is qualitatively similar to a limited amount of measured data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012epsc.conf..910G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012epsc.conf..910G"><span>Coupling approaches used in <span class="hlt">atmospheric</span> entry <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gritsevich, M. I.</p> <p>2012-09-01</p> <p>While a planet orbits the Sun, it is subject to impact by smaller objects, ranging from tiny dust particles and space debris to much larger asteroids and comets. Such collisions have taken place frequently over geological time and played an important role in the evolution of planets and the development of life on the Earth. Though the search for near-Earth objects addresses one of the main points of the Asteroid and Comet Hazard, one should not underestimate the useful information to be gleaned from smaller <span class="hlt">atmospheric</span> encounters, known as meteors or fireballs. Not only do these events help determine the linkages between meteorites and their parent bodies; due to their relative regularity they provide a good statistical basis for analysis. For successful cases with found meteorites, the detailed <span class="hlt">atmospheric</span> path record is an excellent tool to test and improve existing entry <span class="hlt">models</span> assuring the robustness of their implementation. There are many more important scientific questions meteoroids help us to answer, among them: Where do these objects come from, what are their origins, physical properties and chemical composition? What are the shapes and bulk densities of the space objects which fully ablate in an <span class="hlt">atmosphere</span> and do not reach the planetary surface? Which values are directly measured and which are initially assumed as input to various <span class="hlt">models</span>? How to couple both fragmentation and ablation effects in the <span class="hlt">model</span>, taking real size distribution of fragments into account? How to specify and speed up the recovery of a recently fallen meteorites, not letting weathering to affect samples too much? How big is the pre-<span class="hlt">atmospheric</span> projectile to terminal body ratio in terms of their mass/volume? Which exact parameters beside initial mass define this ratio? More generally, how entering object affects Earth's <span class="hlt">atmosphere</span> and (if applicable) Earth's surface? How to predict these impact consequences based on <span class="hlt">atmospheric</span> trajectory data? How to describe <span class="hlt">atmospheric</span> entry</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914115K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914115K"><span>Systematic evaluation of <span class="hlt">atmospheric</span> chemistry-transport <span class="hlt">model</span> CHIMERE</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khvorostyanov, Dmitry; Menut, Laurent; Mailler, Sylvain; Siour, Guillaume; Couvidat, Florian; Bessagnet, Bertrand; Turquety, Solene</p> <p>2017-04-01</p> <p>Regional-scale <span class="hlt">atmospheric</span> chemistry-transport <span class="hlt">models</span> (CTM) are used to develop air quality regulatory measures, to support environmentally sensitive decisions in the industry, and to address variety of scientific questions involving the <span class="hlt">atmospheric</span> composition. <span class="hlt">Model</span> performance evaluation with measurement data is critical to understand their limits and the degree of confidence in <span class="hlt">model</span> results. CHIMERE CTM (http://www.lmd.polytechnique.fr/chimere/) is a French national tool for operational forecast and decision support and is widely used in the international research <span class="hlt">community</span> in various areas of <span class="hlt">atmospheric</span> chemistry and physics, climate, and environment (http://www.lmd.polytechnique.fr/chimere/CW-articles.php). This work presents the <span class="hlt">model</span> evaluation framework applied systematically to the new CHIMERE CTM versions in the course of the continuous <span class="hlt">model</span> development. The framework uses three of the four CTM evaluation types identified by the Environmental Protection Agency (EPA) and the American Meteorological Society (AMS): operational, diagnostic, and dynamic. It allows to compare the overall <span class="hlt">model</span> performance in subsequent <span class="hlt">model</span> versions (operational evaluation), identify specific processes and/or <span class="hlt">model</span> inputs that could be improved (diagnostic evaluation), and test the <span class="hlt">model</span> sensitivity to the changes in air quality, such as emission reductions and meteorological events (dynamic evaluation). The observation datasets currently used for the evaluation are: EMEP (surface concentrations), AERONET (optical depths), and WOUDC (ozone sounding profiles). The framework is implemented as an automated processing chain and allows interactive exploration of the results via a web interface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.1748L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.1748L"><span>Earth Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> 2007 (Earth-GRAM07)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leslie, Fred</p> <p></p> <p>Engineering <span class="hlt">models</span> of the <span class="hlt">atmosphere</span> are used extensively by the aerospace <span class="hlt">community</span> for design issues related to vehicle ascent and descent. The Earth Global Reference <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 2007 (Earth-GRAM07) is the latest in this series and includes a number of new features. Like previous versions, Earth-GRAM07 provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthlyand geographically-varying trace constituent concentrations. From 0 km to 27 km, thermodynamics and winds are based on the National Oceanic and <span class="hlt">Atmospheric</span> Administration Global Upper Air Climatic Atlas (GUACA) climatology. For altitudes between 20 km and 120 km, the <span class="hlt">model</span> uses data from the Middle <span class="hlt">Atmosphere</span> Program (MAP). Above 120 km, Earth-GRAM07 now provides users with a choice of three thermosphere <span class="hlt">models</span>: the Marshall Engineering Thermosphere (MET-2007) <span class="hlt">model</span>; the Jacchia-Bowman 2006 thermosphere <span class="hlt">model</span> (JB2006); and the Naval Research Labs Mass Spectrometer, Incoherent Scatter Radar Extended <span class="hlt">Model</span> (NRL MSIS E-00) with the associated Harmonic Wind <span class="hlt">Model</span> (HWM-93). In place of the GUACA and MAP datasets, Earth-GRAM07 has the option of using the new 2006 revised Range Reference <span class="hlt">Atmosphere</span> (RRA) data, the earlier (1983) RRA data, or the user may provide their own data as an auxiliary profile. Refinements of the perturbation <span class="hlt">model</span> are also discussed which produce wind shears more similar to those observed at the Kennedy Space Center than the previous version Earth-GRAM99. In addition, the dispersions are more normally distributed, especially at the extremes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.2205C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.2205C"><span>Internal <span class="hlt">atmospheric</span> noise characteristics in twentieth century coupled <span class="hlt">atmosphere</span>-ocean <span class="hlt">model</span> simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colfescu, Ioana; Schneider, Edwin K.</p> <p>2017-09-01</p> <p>The statistical characteristics of the <span class="hlt">atmospheric</span> internal variability (hereafter internal <span class="hlt">atmospheric</span> noise) for surface pressure (PS) in twentieth century simulations of a coupled general circulation <span class="hlt">model</span> are documented. The <span class="hlt">atmospheric</span> noise is determined from daily post-industrial (1871-1998) <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> 3 simulations by removing the SST and externally forced responses from the total fields. The forced responses are found from <span class="hlt">atmosphere</span>-only simulations forced by the SST and external forcing of the coupled runs. However, we do not address the influence of the SST variability on the synoptic scale high frequency weather noise.The spatial patterns of the main seasonal modes of <span class="hlt">atmospheric</span> noise variability are found for boreal winter and summer from empirical orthogonal function analyses performed globally and for various regions, including the North Atlantic, the North Pacific, and the equatorial Pacific. The temporal characteristics of the modes are illustrated by power spectra and probability density functions (PDF) of the principal components (PC). Our findings show that, for two different realizations of noise, the variability is dominated by large scale spatial structures of the <span class="hlt">atmospheric</span> noise that resemble observed patterns, and that their relative amplitudes in the CGCM and AGCM simulations are very similar. The regional expression of the dominant global mode, a seasonally dependent AO-like or AAO-like pattern is also found in the regional analyses, with similar time dependence. The PCs in the CGCM and the corresponding SST forced AGCM simulations are uncorrelated, but the spectra and PDFs of the CGCM and AGCM PCs are similar.The temporal structures of the noise PCs are white at timescales larger than few months, so that these modes can be thought of as stochastic forcings (in time) for the climate system. The PDFs of the noise PCs are not statistically distinguishable from Gaussian distributions with the same standard deviation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy..tmp..475C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..475C"><span>Internal <span class="hlt">atmospheric</span> noise characteristics in twentieth century coupled <span class="hlt">atmosphere</span>-ocean <span class="hlt">model</span> simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colfescu, Ioana; Schneider, Edwin K.</p> <p>2016-11-01</p> <p>The statistical characteristics of the <span class="hlt">atmospheric</span> internal variability (hereafter internal <span class="hlt">atmospheric</span> noise) for surface pressure (PS) in twentieth century simulations of a coupled general circulation <span class="hlt">model</span> are documented. The <span class="hlt">atmospheric</span> noise is determined from daily post-industrial (1871-1998) <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> 3 simulations by removing the SST and externally forced responses from the total fields. The forced responses are found from <span class="hlt">atmosphere</span>-only simulations forced by the SST and external forcing of the coupled runs. However, we do not address the influence of the SST variability on the synoptic scale high frequency weather noise.The spatial patterns of the main seasonal modes of <span class="hlt">atmospheric</span> noise variability are found for boreal winter and summer from empirical orthogonal function analyses performed globally and for various regions, including the North Atlantic, the North Pacific, and the equatorial Pacific. The temporal characteristics of the modes are illustrated by power spectra and probability density functions (PDF) of the principal components (PC). Our findings show that, for two different realizations of noise, the variability is dominated by large scale spatial structures of the <span class="hlt">atmospheric</span> noise that resemble observed patterns, and that their relative amplitudes in the CGCM and AGCM simulations are very similar. The regional expression of the dominant global mode, a seasonally dependent AO-like or AAO-like pattern is also found in the regional analyses, with similar time dependence. The PCs in the CGCM and the corresponding SST forced AGCM simulations are uncorrelated, but the spectra and PDFs of the CGCM and AGCM PCs are similar.The temporal structures of the noise PCs are white at timescales larger than few months, so that these modes can be thought of as stochastic forcings (in time) for the climate system. The PDFs of the noise PCs are not statistically distinguishable from Gaussian distributions with the same standard deviation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/940221','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/940221"><span>A New Two-Moment Bulk Stratiform Cloud Microphysics Scheme in the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span>, Version 3 (CAM3). Part II: Single-Column and Global Results</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gettelman, A.; Morrison, H.; Ghan, Steven J.</p> <p>2008-08-11</p> <p>The global performance of a new 2-moment cloud microphysics scheme for a General Circulation <span class="hlt">Model</span> (GCM) is presented and evaluated relative to observations. The scheme produces reasonable representations of cloud particle size and number concentration when compared to observations, and represents expected and observed spatial variations in cloud microphysical quantities. The scheme has smaller particles and higher number concentrations over land than the standard bulk microphysics in the GCM, and is able to balance the radiation budget of the planet with 60% the liquid water of the standard scheme, in better agreement with observations. The new scheme treats both the mixing ratio and number concentration of rain and snow, and is therefore able to differentiate the two key regimes, consisting of drizzle in shallow warm clouds and larger rain drops in deeper cloud systems. The <span class="hlt">modeled</span> rain and snow size distributions are consistent with observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940019914','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940019914"><span>Coupled land surface/hydrologic/<span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pielke, Roger; Steyaert, Lou; Arritt, Ray; Lahtakia, Mercedes; Smith, Chris; Ziegler, Conrad; Soong, Su Tzai; Avissar, Roni; Wetzel, Peter; Sellers, Piers</p> <p>1993-01-01</p> <p>The topics covered include the following: prototype land cover characteristics data base for the conterminous United States; surface evapotranspiration effects on cumulus convection and implications for mesoscale <span class="hlt">models</span>; the use of complex treatment of surface hydrology and thermodynamics within a mesoscale <span class="hlt">model</span> and some related issues; initialization of soil-water content for regional-scale <span class="hlt">atmospheric</span> prediction <span class="hlt">models</span>; impact of surface properties on dryline and MCS evolution; a numerical simulation of heavy precipitation over the complex topography of California; representing mesoscale fluxes induced by landscape discontinuities in global climate <span class="hlt">models</span>; emphasizing the role of subgrid-scale heterogeneity in surface-air interaction; and problems with <span class="hlt">modeling</span> and measuring biosphere-<span class="hlt">atmosphere</span> exchanges of energy, water, and carbon on large scales.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AnGeo..35..181C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AnGeo..35..181C"><span>Large-scale gravity wave perturbations in the mesopause region above Northern Hemisphere midlatitudes during autumnal equinox: a joint study by the USU Na lidar and Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cai, Xuguang; Yuan, Tao; Liu, Han-Li</p> <p>2017-02-01</p> <p>To investigate gravity wave (GW) perturbations in the midlatitude mesopause region during boreal equinox, 433 h of continuous Na lidar full diurnal cycle temperature measurements in September between 2011 and 2015 are utilized to derive the monthly profiles of GW-induced temperature variance, T'2, and the potential energy density (PED). Operating at Utah State University (42° N, 112° W), these lidar measurements reveal severe GW dissipation near 90 km, where both parameters drop to their minima (˜ 20 K2 and ˜ 50 m2 s-2, respectively). The study also shows that GWs with periods of 3-5 h dominate the midlatitude mesopause region during the summer-winter transition. To derive the precise temperature perturbations a new tide removal algorithm suitable for all ground-based observations is developed to de-trend the lidar temperature measurements and to isolate GW-induced perturbations. It removes the tidal perturbations completely and provides the most accurate GW perturbations for the ground-based observations. This algorithm is validated by comparing the true GW perturbations in the latest mesoscale-resolving Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM) with those derived from the WACCM local outputs by applying this newly developed tidal removal algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6680G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6680G"><span>The Intermediate Complexity <span class="hlt">Atmospheric</span> Research <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gutmann, Ethan; Clark, Martyn; Rasmussen, Roy; Arnold, Jeffrey; Brekke, Levi</p> <p>2015-04-01</p> <p>The high-resolution, non-hydrostatic <span class="hlt">atmospheric</span> <span class="hlt">models</span> often used for dynamical downscaling are extremely computationally expensive, and, for a certain class of problems, their complexity hinders our ability to ask key scientific questions, particularly those related to hydrology and climate change. For changes in precipitation in particular, an <span class="hlt">atmospheric</span> <span class="hlt">model</span> grid spacing capable of resolving the structure of mountain ranges is of critical importance, yet such simulations can not currently be performed with an advanced regional climate <span class="hlt">model</span> for long time periods, over large areas, and forced by many climate <span class="hlt">models</span>. Here we present the newly developed Intermediate Complexity <span class="hlt">Atmospheric</span> Research <span class="hlt">model</span> (ICAR) capable of simulating critical <span class="hlt">atmospheric</span> processes two to three orders of magnitude faster than a state of the art regional climate <span class="hlt">model</span>. ICAR uses a simplified dynamical formulation based off of linear theory, combined with the circulation field from a low-resolution climate <span class="hlt">model</span>. The resulting three-dimensional wind field is used to advect heat and moisture within the domain, while sub-grid physics (e.g. microphysics) are processed by standard and simplified physics schemes from the Weather Research and Forecasting (WRF) <span class="hlt">model</span>. ICAR is tested in comparison to WRF by downscaling a climate change scenario over the Colorado Rockies. Both <span class="hlt">atmospheric</span> <span class="hlt">models</span> predict increases in precipitation across the domain with a greater increase on the western half. In contrast, statistically downscaled precipitation using multiple common statistical methods predict decreases in precipitation over the western half of the domain. Finally, we apply ICAR to multiple CMIP5 climate <span class="hlt">models</span> and scenarios with multiple parameterization options to investigate the importance of uncertainty in sub-grid physics as compared to the uncertainty in the large scale climate scenario. ICAR is a useful tool for climate change and weather forecast downscaling, particularly for orographic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017LPICo2022.8012J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017LPICo2022.8012J"><span>Thermodynamic <span class="hlt">Modeling</span> of the Lower Venusian <span class="hlt">Atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jacobson, N. S.; Kulis, M. J.; Radoman-Shaw, B.; Harvey, R.; Myers, D.; Schaefer, L.; Fegley, B.</p> <p>2017-05-01</p> <p>The lower venusian <span class="hlt">atmosphere</span> is the region from the surface to the cloud deck, which is approximately 0-50 km. We introduce an very small increasing oxygen gradient from the surface to the cloud layer to <span class="hlt">model</span> some features with thermodynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001STIN...0311545W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001STIN...0311545W"><span>Observations and <span class="hlt">Modeling</span> of <span class="hlt">Atmospheric</span> Radiance Structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wintersteiner, Peter P.</p> <p>2001-11-01</p> <p>The overall purpose of the work that we have undertaken is to provide new capabilities for observing and <span class="hlt">modeling</span> structured radiance in the <span class="hlt">atmosphere</span>, particularly the non-LTE regions of the <span class="hlt">atmosphere</span>. This purpose is well served by the work reported below. It is supplemented by the transition of some of our <span class="hlt">modeling</span> and simulation capabilities to the Air Force, in the form of codes that we have developed and advice or assistance related to their use. Several investigations related to <span class="hlt">atmospheric</span> radiance structure have been carried out. We used auroral data from the MSX UVISI Spectrographic Imagers in the EUV, visible, and NIR wavelengths to demonstrate the excellent spatial and temporal resolution of those instruments, and their utility for studying radiance structure. We identified small perturbations in the 4.3 micro below-the-horizon data from the MSX SPIRIT III radiometer as originating in the stratosphere, helping to confirm that the structure was produced by upwelling thunderstorm-produced gravity waves. We derived and implemented a new transfer-function algorithm in <span class="hlt">Atmospheric</span> Radiance Code (ARC), and demonstrated its functionality. It enables rapid and repetitive non-LTE calculations to be carried out, which is essential for forward <span class="hlt">modeling</span> of radiance structure. We participated in the development of the first non-LTE kinetic temperature retrieval algorithm, which will be useful for returning profiles above 100 km using data from the SABER instrument aboard NASA's TIMED satellite, and we used ARC for related <span class="hlt">model</span> development and validation purposes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=297340','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=297340"><span><span class="hlt">Atmospheric</span> CO2 enrichment and grassland productivity: Scaling CO2 effects through the plant <span class="hlt">community</span></span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>Ecosystem responses to <span class="hlt">atmospheric</span> CO2 enrichment, as to other climate change drivers, depend on plant <span class="hlt">community</span> responses to CO2 (<span class="hlt">community</span> response) and feedbacks from <span class="hlt">community</span> change on ecosystem processes (<span class="hlt">community</span> effect). We used data from two multi-year experiments in central Texas, USA to...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030001123&hterms=nrl&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dnrl','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030001123&hterms=nrl&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dnrl"><span>Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> and Trace Constituents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C.; Johnson, D.; Parker, Nelson C. (Technical Monitor)</p> <p>2002-01-01</p> <p>Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (GRAM-99) is an engineering-level <span class="hlt">model</span> of the Earth's <span class="hlt">atmosphere</span>. It provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0-27 km, thermodynamics and winds are based on National Oceanic and <span class="hlt">Atmospheric</span> Administration Global Upper Air Climatic Atlas (GUACA) climatology. Above 120 km, GRAM is based on the NASA Marshall Engineering Thermosphere (MET) <span class="hlt">model</span>. In the intervening altitude region, GRAM is based on Middle <span class="hlt">Atmosphere</span> Program (MAP) climatology that also forms the basis of the 1986 COSPAR Intemationa1 Reference <span class="hlt">Atmosphere</span> (CIRA). MAP data in GRAM are augmented by a specially-derived longitude variation climatology. <span class="hlt">Atmospheric</span> composition is represented in GRAM by concentrations of both major and minor species. Above 120 km, MET provides concentration values for N2, O2, Ar, O, He, and H. Below 120 km, species represented also include H2O, O3, N2O, CO, CH, and CO2. Water vapor in GRAM is based on a combination of GUACA, Air Force Geophysics Laboratory (AFGL), and NASA Langley Research Center climatologies. Other constituents below 120 km are based on a combination of AFGL and h4AP/CIRA climatologies. This report presents results of comparisons between GRAM Constituent concentrations and those provided by the Naval Research Laboratory (NRL) climatology of Summers (NRL,/MR/7641-93-7416, 1993). GRAM and NRL concentrations were compared for seven species (CH4, CO, CO2, H2O, N2O, O2, and O3) for months January, April, July, and October, over height range 0-115 km, and latitudes -90deg to + 90deg at 10deg increments. Average GRAM-NRL correlations range from 0.878 (for CO) to 0.975 (for O3), with an average over all seven species of 0.936 (standard deviation 0.049).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030001123&hterms=National+Oceanic+Atmospheric+Administration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNational%2BOceanic%2BAtmospheric%2BAdministration','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030001123&hterms=National+Oceanic+Atmospheric+Administration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNational%2BOceanic%2BAtmospheric%2BAdministration"><span>Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> and Trace Constituents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C.; Johnson, D.; Parker, Nelson C. (Technical Monitor)</p> <p>2002-01-01</p> <p>Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (GRAM-99) is an engineering-level <span class="hlt">model</span> of the Earth's <span class="hlt">atmosphere</span>. It provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0-27 km, thermodynamics and winds are based on National Oceanic and <span class="hlt">Atmospheric</span> Administration Global Upper Air Climatic Atlas (GUACA) climatology. Above 120 km, GRAM is based on the NASA Marshall Engineering Thermosphere (MET) <span class="hlt">model</span>. In the intervening altitude region, GRAM is based on Middle <span class="hlt">Atmosphere</span> Program (MAP) climatology that also forms the basis of the 1986 COSPAR Intemationa1 Reference <span class="hlt">Atmosphere</span> (CIRA). MAP data in GRAM are augmented by a specially-derived longitude variation climatology. <span class="hlt">Atmospheric</span> composition is represented in GRAM by concentrations of both major and minor species. Above 120 km, MET provides concentration values for N2, O2, Ar, O, He, and H. Below 120 km, species represented also include H2O, O3, N2O, CO, CH, and CO2. Water vapor in GRAM is based on a combination of GUACA, Air Force Geophysics Laboratory (AFGL), and NASA Langley Research Center climatologies. Other constituents below 120 km are based on a combination of AFGL and h4AP/CIRA climatologies. This report presents results of comparisons between GRAM Constituent concentrations and those provided by the Naval Research Laboratory (NRL) climatology of Summers (NRL,/MR/7641-93-7416, 1993). GRAM and NRL concentrations were compared for seven species (CH4, CO, CO2, H2O, N2O, O2, and O3) for months January, April, July, and October, over height range 0-115 km, and latitudes -90deg to + 90deg at 10deg increments. Average GRAM-NRL correlations range from 0.878 (for CO) to 0.975 (for O3), with an average over all seven species of 0.936 (standard deviation 0.049).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/892794','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/892794"><span>The <span class="hlt">Community</span> Climate System <span class="hlt">Model</span>: CCSM3</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Collins, W D; Blackmon, M; Bitz, C; Bonan, G; Bretherton, C S; Carton, J A; Chang, P; Doney, S; Hack, J J; Kiehl, J T; Henderson, T; Large, W G; McKenna, D; Santer, B D; Smith, R D</p> <p>2004-12-27</p> <p>A new version of the <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> (CCSM) has been developed and released to the climate <span class="hlt">community</span>. CCSM3 is a coupled climate <span class="hlt">model</span> with components representing the <span class="hlt">atmosphere</span>, ocean, sea ice, and land surface connected by a flux coupler. CCSM3 is designed to produce realistic simulations over a wide range of spatial resolutions, enabling inexpensive simulations lasting several millennia or detailed studies of continental-scale climate change. This paper will show results from the configuration used for climate-change simulations with a T85 grid for <span class="hlt">atmosphere</span> and land and a 1-degree grid for ocean and sea-ice. The new system incorporates several significant improvements in the scientific formulation. The enhancements in the <span class="hlt">model</span> physics are designed to reduce or eliminate several systematic biases in the mean climate produced by previous editions of CCSM. These include new treatments of cloud processes, aerosol radiative forcing, land-<span class="hlt">atmosphere</span> fluxes, ocean mixed-layer processes, and sea-ice dynamics. There are significant improvements in the sea-ice thickness, polar radiation budgets, equatorial sea-surface temperatures, ocean currents, cloud radiative effects, and ENSO teleconnections. CCSM3 can produce stable climate simulations of millenial duration without ad hoc adjustments to the fluxes exchanged among the component <span class="hlt">models</span>. Nonetheless, there are still systematic biases in the ocean-<span class="hlt">atmosphere</span> fluxes in western coastal regions, the spectrum of ENSO variability, the spatial distribution of precipitation in the Pacific and Indian Oceans, and the continental precipitation and surface air temperatures. We conclude with the prospects for extending CCSM to a more comprehensive <span class="hlt">model</span> of the Earth's climate system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10194E..05W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10194E..05W"><span>Horizontal <span class="hlt">atmospheric</span> turbulence, beam propagation, and <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilcox, Christopher C.; Santiago, Freddie; Martinez, Ty; Judd, K. Peter; Restaino, Sergio R.</p> <p>2017-05-01</p> <p>The turbulent effect from the Earth's <span class="hlt">atmosphere</span> degrades the performance of an optical imaging system. Many studies have been conducted in the study of beam propagation in a turbulent medium. Horizontal beam propagation and correction presents many challenges when compared to vertical due to the far harsher turbulent conditions and increased complexity it induces. We investigate the collection of beam propagation data, analysis, and use for building a mathematical <span class="hlt">model</span> of the horizontal turbulent path and the plans for an adaptive optical system to use this information to correct for horizontal path <span class="hlt">atmospheric</span> turbulence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990AdSpR..10...37K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990AdSpR..10...37K"><span>Improved reference <span class="hlt">models</span> for middle <span class="hlt">atmosphere</span> ozone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keating, G. M.; Pitts, M. C.; Chen, C.</p> <p></p> <p>This paper describes the improvements introduced into the original version of ozone reference <span class="hlt">model</span> of Keating and Young (1985, 1987) which is to be incorporated in the next COSPAR International Reference <span class="hlt">Atmosphere</span> (CIRA). The ozone reference <span class="hlt">model</span> will provide information on the global ozone distribution (including the ozone vertical structure as a function of month and latitude from 25 to 90 km) combining data from five recent satellite experiments: the Nimbus 7 LIMS, Nimbus 7 SBUV, AE-2 Stratospheric Aerosol Gas Experiment (SAGE), Solar Mesosphere Explorer (SME) UV Spectrometer, and SME 1.27 Micron Airglow. The improved version of the reference <span class="hlt">model</span> uses reprocessed AE-2 SAGE data (sunset) and extends the use of SAGE data from 1981 to the 1981-1983 time period. Comparisons are presented between the results of this ozone <span class="hlt">model</span> and various nonsatellite measurements at different levels in the middle <span class="hlt">atmosphere</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900034126&hterms=sage+1987&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsage%2B1987','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900034126&hterms=sage+1987&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dsage%2B1987"><span>Improved reference <span class="hlt">models</span> for middle <span class="hlt">atmosphere</span> ozone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keating, G. M.; Pitts, M. C.; Chen, C.</p> <p>1990-01-01</p> <p>This paper describes the improvements introduced into the original version of ozone reference <span class="hlt">model</span> of Keating and Young (1985, 1987) which is to be incorporated in the next COSPAR International Reference <span class="hlt">Atmosphere</span> (CIRA). The ozone reference <span class="hlt">model</span> will provide information on the global ozone distribution (including the ozone vertical structure as a function of month and latitude from 25 to 90 km) combining data from five recent satellite experiments: the Nimbus 7 LIMS, Nimbus 7 SBUV, AE-2 Stratospheric Aerosol Gas Experiment (SAGE), Solar Mesosphere Explorer (SME) UV Spectrometer, and SME 1.27 Micron Airglow. The improved version of the reference <span class="hlt">model</span> uses reprocessed AE-2 SAGE data (sunset) and extends the use of SAGE data from 1981 to the 1981-1983 time period. Comparisons are presented between the results of this ozone <span class="hlt">model</span> and various nonsatellite measurements at different levels in the middle <span class="hlt">atmosphere</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AnRFM..42..249K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AnRFM..42..249K"><span>Scale-Dependent <span class="hlt">Models</span> for <span class="hlt">Atmospheric</span> Flows</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Klein, Rupert</p> <p>2010-01-01</p> <p><span class="hlt">Atmospheric</span> flows feature length scales from 10-5 to 105 m and timescales from microseconds to weeks or more. For scales above several kilometers and minutes, there is a natural scale separation induced by the <span class="hlt">atmosphere</span>'s thermal stratification, together with the influences of gravity and Earth's rotation, and the fact that <span class="hlt">atmospheric</span>-flow Mach numbers are typically small. A central aim of theoretical meteorology is to understand the associated scale-specific flow phenomena, such as internal gravity waves, baroclinic instabilities, Rossby waves, cloud formation and moist convection, (anti-)cyclonic weather patterns, hurricanes, and a variety of interacting waves in the tropics. Single-scale asymptotics yields reduced sets of equations that capture the essence of these scale-specific processes. For studies of interactions across scales, techniques of multiple-scales asymptotics have received increasing recognition in recent years. This article recounts the most prominent scales and associated scale-dependent <span class="hlt">models</span> and summarizes recent multiple-scales developments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016DPS....4840405V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016DPS....4840405V"><span><span class="hlt">Atmospheric</span> distribution of methane on Mars: A <span class="hlt">model</span> study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Viscardy, Sébastien; Daerden, Frank; Neary, Lori</p> <p>2016-10-01</p> <p>In the past decade, the detection of methane (CH4) in the <span class="hlt">atmosphere</span> of Mars has been reported several times. These observations have strongly drawn the attention of the scientific <span class="hlt">community</span> and triggered a renewed interest in Mars as their implications for the geochemical or biological activities are remarkable. However, given that methane is expected to have a photochemical lifetime of several centuries, the relatively fast loss rates of methane estimated from Earth-based measurements remain unexplained. Although this gave rise to objections against the validity of those observations, recent in situ measurements confirmed that methane is being occasionally released into the <span class="hlt">atmosphere</span> from an unknown source (possibly from the ground). Additionally, ExoMars/TGO was launched to Mars in March 2016. NOMAD, one of the instruments onboard TGO, will provide the first global detailed observations of methane on Mars. It is in this context that we present a <span class="hlt">model</span> study of the behavior of methane plumes.A general circulation <span class="hlt">model</span> for the <span class="hlt">atmosphere</span> of Mars is applied to simulate surface emission of methane and to investigate its vertical distribution during the first weeks after the release. Such surface emissions were suggested to explain observations of methane. Previous GCM simulations focused on the horizontal evolution of the methane, but the present study focuses on the three-dimensional dispersion of methane throughout the <span class="hlt">atmosphere</span> after the surface release. It is found that a highly nonuniform vertical distribution, including distinct vertical layers, can appear throughout the <span class="hlt">atmosphere</span> during the first weeks after the emission. This is explained by the global circulation patterns in the <span class="hlt">atmosphere</span> at the time of the emission. Large Hadley cells transport the methane rapidly to other locations over the planet, and methane will be stretched out in layers along the general circulation streamlines at heights corresponding to strong zonal jets.This result changes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=88340&keyword=computing+AND+cloud&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78087265&CFTOKEN=18577126','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=88340&keyword=computing+AND+cloud&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78087265&CFTOKEN=18577126"><span>NEW DEVELOPMENTS IN THE <span class="hlt">COMMUNITY</span> MULTISCALE AIR QUALITY (CMAQ) <span class="hlt">MODEL</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>CMAQ <span class="hlt">model</span> research and development is currently following two tracks at the <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> Division of the USEPA. Public releases of the <span class="hlt">community</span> <span class="hlt">model</span> system for research and policy analysis is continuing on an annual interval with the latest release scheduled for Augus...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=88340&keyword=cloud+AND+computing&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=88340&keyword=cloud+AND+computing&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>NEW DEVELOPMENTS IN THE <span class="hlt">COMMUNITY</span> MULTISCALE AIR QUALITY (CMAQ) <span class="hlt">MODEL</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>CMAQ <span class="hlt">model</span> research and development is currently following two tracks at the <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> Division of the USEPA. Public releases of the <span class="hlt">community</span> <span class="hlt">model</span> system for research and policy analysis is continuing on an annual interval with the latest release scheduled for Augus...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AtmEn..81...39J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AtmEn..81...39J"><span>Impacts of Asian dust events on <span class="hlt">atmospheric</span> fungal <span class="hlt">communities</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jeon, Eun Mi; Kim, Yong Pyo; Jeong, Kweon; Kim, Ik Soo; Eom, Suk Won; Choi, Young Zoo; Ka, Jong-Ok</p> <p>2013-12-01</p> <p>The composition of <span class="hlt">atmospheric</span> fungi in Seoul during Asian dust events were assessed by culturing and by molecular methods such as mold specific quantitative PCR (MSQPCR) and internal transcribed spacer cloning (ITS cloning). Culturable fungal concentrations in the air were monitored from May 2008 to July 2011 and 3 pairs of ITS clone libraries, one during Asian dust (AD) day and the other during the adjacent non Asian dust (NAD) day for each pair, were constructed after direct DNA extraction from total suspended particles (TSP) samples. In addition, six aeroallergenic fungi in the <span class="hlt">atmosphere</span> were also assessed by MSQPCR from October, 2009 to November, 2011. The levels of the airborne culturable fungal concentrations during AD days was significantly higher than that of NAD days (P < 0.005). In addition, the correlation of culturable fungal concentrations with particulate matters equal to or less than 10 μm in aerodynamic diameter (PM10) concentrations was observed to be high (0.775) for the AD days while correlation coefficients of PM10 as well as other particulate parameters with airborne fungal concentrations were significantly negative for the NAD days during intensive monitoring periods (May to June, 2008). It was found that during AD days several airborne allergenic fungal levels measured with MSQPCR increased up to 5-12 times depending on the species. Comparison of AD vs. NAD clones showed significant differences (P < 0.05) in all three cases using libshuff. In addition, high proportions of uncultured soil fungus isolated from semi-arid regions were observed only in AD clone libraries. Thus, it was concluded that AD impacts not only airborne fungal concentrations but also fungal <span class="hlt">communities</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A41C0046S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A41C0046S"><span>Coupled <span class="hlt">Atmospheric</span> Chemistry Schemes for <span class="hlt">Modeling</span> Regional and Global <span class="hlt">Atmospheric</span> Chemistry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saunders, E.; Stockwell, W. R.</p> <p>2016-12-01</p> <p><span class="hlt">Atmospheric</span> chemistry <span class="hlt">models</span> require chemical reaction mechanisms to simulate the production of air pollution. GACM (Global <span class="hlt">Atmospheric</span> Chemistry Mechanism) is intended for use in global scale <span class="hlt">atmospheric</span> chemistry <span class="hlt">models</span> to provide chemical boundary conditions for regional scale simulations by <span class="hlt">models</span> such as CMAQ. GACM includes additional chemistry for marine environments while reducing its treatment of the chemistry needed for highly polluted urban regions. This keeps GACM's size small enough to allow it to be used efficiently in global <span class="hlt">models</span>. GACM's chemistry of volatile organic compounds (VOC) is highly compatible with the VOC chemistry in RACM2 allowing a global <span class="hlt">model</span> with GACM to provide VOC boundary conditions to a regional scale <span class="hlt">model</span> with RACM2 with reduced error. The GACM-RACM2 system of mechanisms should yield more accurate forecasts by regional air quality <span class="hlt">models</span> such as CMAQ. Chemical box <span class="hlt">models</span> coupled with the regional and global <span class="hlt">atmospheric</span> chemistry mechanisms (RACM2 & GACM) will be used to make simulations of tropospheric ozone, nitric oxides, and volatile organic compounds that are produced in regional and global domains. The simulations will focus on the Los Angeles' South Coast Air Basin (SoCAB) where the Pacific Ocean meets a highly polluted urban area. These two mechanisms will be compared on the basis of simulated ozone concentrations over this marine-urban region. Simulations made with the more established RACM2 will be compared with simulations made with the newer GACM. In addition WRF-Chem will be used to simulate how RACM2 will produce regional simulations of tropospheric ozone and NOx, which can be further, analyzed for air quality impacts. Both the regional and global <span class="hlt">model</span> in WRF-Chem will be used to predict how the concentrations of ozone and nitrogen oxides change over land and ocean. The air quality <span class="hlt">model</span> simulation results will be applied to EPA's BenMAP-CE (Environmental Benefits Mapping & Analysis Program-<span class="hlt">Community</span> Edition</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A24A..03L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A24A..03L"><span><span class="hlt">Community</span> Radiative Transfer <span class="hlt">Model</span> Applications - A Study of the Retrieval of Trace Gases in the <span class="hlt">Atmosphere</span> from Cross-track Infrared Sounder (CrIS) Data of a Full-spectral Resolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Q.; Nalli, N. R.; Tan, C.; Zhang, K.; Iturbide, F.; Wilson, M.; Zhou, L.</p> <p>2015-12-01</p> <p>The <span class="hlt">Community</span> Radiative Transfer <span class="hlt">Model</span> (CRTM) [3] operationally supports satellite radiance assimilation for weather forecasting, sensor data verification, and the retrievals of satellite products. The CRTM has been applied to UV and visible sensors, infrared and microwave sensors. The paper will demonstrate the applications of the CRTM, in particular radiative transfer in the retrieva algorithm. The NOAA Unique CrIS/ATMS Processing System (NUCAPS) operationally generates vertical profiles of <span class="hlt">atmospheric</span> temperature (AVTP) and moisture (AVMP) from Suomi NPP Cross-track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) measurements. Current operational CrIS data have reduced spectral resolution: 1.25 cm-1 for a middle wave band and 2.5 cm-1 for a short-wave wave band [1]. The reduced spectral data largely degraded the retrieval accuracy of trace gases. CrIS full spectral data are also available now which have single spectral resolution of 0.625 cm-1 for all of the three bands: long-wave band, middle wave band, and short-wave band. The CrIS full-spectral resolution data is critical to the retrieval of trace gases such as O3, CO [2], CO2, and CH4. In this paper, we use the <span class="hlt">Community</span> Radiative Transfer <span class="hlt">Model</span> (CRTM) to study the impact of the CrIS spectral resolution on the retrieval accuracy of trace gases. The newly released CRTM version 2.2.1 can simulates Hamming-apodized CrIS radiance of a full-spectral resolution. We developed a small utility that can convert the CRTM simulated radiance to un-apodized radiance. The latter has better spectral information which can be helpful to the retrievals of the trace gases. The retrievals will be validated using both NWP <span class="hlt">model</span> data as well as the data collected during AEROSE expeditions [4]. We will also discuss the sensitivity on trace gases between apodized and un-apodized radiances. References[1] Gambacorta, A., et al.(2013), IEEE Lett., 11(9), doi:10.1109/LGRS.2014.230364, 1639-1643. [2] Han, Y., et</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336201&simplesearch=1&searchall=nitrogen+or+phosphorus+or+nutrient&noarchive=1&sitype=sa&sitype=pr','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336201&simplesearch=1&searchall=nitrogen+or+phosphorus+or+nutrient&noarchive=1&sitype=sa&sitype=pr"><span><span class="hlt">Modeling</span> and Recent Shift in the Composition of <span class="hlt">Atmospheric</span> ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Nitrogen is an essential building block of all proteins and thus an essential nutrient for all life. Reactive nitrogen, which is naturally produced via enzymatic reactions, forest fires and lightning, is continually recycled and cascades through air, water, and soil media. Human activity has perturbed this cycle through the combustion of fossil fuels and synthesis of fertilizers. In excess reactive nitrogen can lead to ozone and particulate matter formation in the <span class="hlt">atmosphere</span>, biodiversity loss in terrestrial ecosystems and eutrophication in aquatic ecosystems. The anthropogenic contribution to this cycle is now larger than natural sources in the United States and globally. There is a need to improve the <span class="hlt">modeling</span> of the cycling of reactive nitrogen in the environment to better understand how anthropogenic inputs are perturbing air quality and ecosystem health. Here we will present the parameterizations of the multimedia transport processes in the <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">Model</span> and the parameterization of agricultural practices, primarily through mineral fertilizer application to crops, the largest source of environmental reactive nitrogen. Here we will focus on <span class="hlt">modeling</span> of the <span class="hlt">atmospheric</span> and soil components of the nitrogen cascade, with an emphasis on ammonia, emerging measurement techniques, and the potential for <span class="hlt">model</span> improvements using emerging measurements, existing networks and <span class="hlt">modeling</span>. The U.S. EPA’s <span class="hlt">Community</span> Mulitscale Air Quality (CMAQ) <span class="hlt">model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840024894','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840024894"><span>Dynamic <span class="hlt">model</span> of the Earth's upper <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Slowey, J. W.</p> <p>1984-01-01</p> <p>An initial modification to the MSF/J70 Thermospheric <span class="hlt">Model</span>, in which the variations due to sudden geomagnetic disturbances upon the Earth's upper <span class="hlt">atmospheric</span> density structure were <span class="hlt">modeled</span> is presented. This dynamic <span class="hlt">model</span> of the geomagnetic variation included is an improved version of one which SAO developed from the analysis of the ESRO 4 mass spectrometer data that was incorporated in the Jacchia 1977 <span class="hlt">model</span>. The variation with geomagnetic local time as well as with geomagnetic latitude are included, and also the effects due to disturbance of the temperature profiles in the region of energy deposition.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050180355&hterms=space+defense&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dspace%2Bdefense','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050180355&hterms=space+defense&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dspace%2Bdefense"><span>Space Weather <span class="hlt">Modeling</span> at the <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hesse M.</p> <p>2005-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather <span class="hlt">models</span>. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day <span class="hlt">modeling</span> capability for space weather purposes, and to provide <span class="hlt">models</span> for transition to the rapid prototyping centers at the space weather forecast centers. This goal requires dose collaborations with and substantial involvement of the research <span class="hlt">community</span>. The physical regions to be addressed by CCMC-related activities range from the solar <span class="hlt">atmosphere</span> to the Earth's upper <span class="hlt">atmosphere</span>. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center, as well as distributed computing facilities provided by the US Air Force. CCMC also provides, to the research <span class="hlt">community</span>, access to state-of-the-art space research <span class="hlt">models</span>. In this paper we will provide updates on CCMC status, on current plans, research and development accomplishments and goals, and on the <span class="hlt">model</span> testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric <span class="hlt">models</span> currently residing at CCMC, and on plans for validation and verification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060013070&hterms=space+defense&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dspace%2Bdefense','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060013070&hterms=space+defense&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dspace%2Bdefense"><span>Space Weather <span class="hlt">Modeling</span> Services at the <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hesse, Michael</p> <p>2006-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather <span class="hlt">models</span>. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day <span class="hlt">modeling</span> capability for space weather purposes, and to provide <span class="hlt">models</span> for transition to the Rapid Prototyping Centers at the space weather forecast centers. This goal requires close collaborations with and substantial involvement of the research <span class="hlt">community</span>. The physical regions to be addressed by CCMC-related activities range from the solar <span class="hlt">atmosphere</span> to the Earth's upper <span class="hlt">atmosphere</span>. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center. CCMC also provides, to the research <span class="hlt">community</span>, access to state-of-the-art space research <span class="hlt">models</span>. In this paper we will provide a description of the current CCMC status, discuss current plans, research and development accomplishments and goals, and describe the <span class="hlt">model</span> testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric <span class="hlt">models</span> currently residing at CCMC, and on plans for validation and verification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050180355&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050180355&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters"><span>Space Weather <span class="hlt">Modeling</span> at the <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hesse M.</p> <p>2005-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather <span class="hlt">models</span>. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day <span class="hlt">modeling</span> capability for space weather purposes, and to provide <span class="hlt">models</span> for transition to the rapid prototyping centers at the space weather forecast centers. This goal requires dose collaborations with and substantial involvement of the research <span class="hlt">community</span>. The physical regions to be addressed by CCMC-related activities range from the solar <span class="hlt">atmosphere</span> to the Earth's upper <span class="hlt">atmosphere</span>. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center, as well as distributed computing facilities provided by the US Air Force. CCMC also provides, to the research <span class="hlt">community</span>, access to state-of-the-art space research <span class="hlt">models</span>. In this paper we will provide updates on CCMC status, on current plans, research and development accomplishments and goals, and on the <span class="hlt">model</span> testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric <span class="hlt">models</span> currently residing at CCMC, and on plans for validation and verification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060013070&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060013070&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters"><span>Space Weather <span class="hlt">Modeling</span> Services at the <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hesse, Michael</p> <p>2006-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather <span class="hlt">models</span>. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day <span class="hlt">modeling</span> capability for space weather purposes, and to provide <span class="hlt">models</span> for transition to the Rapid Prototyping Centers at the space weather forecast centers. This goal requires close collaborations with and substantial involvement of the research <span class="hlt">community</span>. The physical regions to be addressed by CCMC-related activities range from the solar <span class="hlt">atmosphere</span> to the Earth's upper <span class="hlt">atmosphere</span>. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center. CCMC also provides, to the research <span class="hlt">community</span>, access to state-of-the-art space research <span class="hlt">models</span>. In this paper we will provide a description of the current CCMC status, discuss current plans, research and development accomplishments and goals, and describe the <span class="hlt">model</span> testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric <span class="hlt">models</span> currently residing at CCMC, and on plans for validation and verification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A23B0236L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A23B0236L"><span><span class="hlt">Atmospheric</span> <span class="hlt">models</span> for post- giant impact planets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lupu, R.; Zahnle, K. J.; Marley, M. S.; Schaefer, L. K.; Fegley, B.; Morley, C.; Cahoy, K.; Freedman, R. S.; Fortney, J. J.</p> <p>2013-12-01</p> <p> the reflected and emergent flux. We find that these <span class="hlt">atmospheres</span> are dominated by H2O and CO2, while the formation of CH4, and NH3 is quenched due to short dynamical timescales. Other important constituents are HF, HCl, NaCl, and SO2. These are apparent in the emerging spectra, and can be indicative that an impact has occurred. Estimates including photochemistry and vertical mixing show that these <span class="hlt">atmospheres</span> are enhanced in sulfur-bearing species, particularly SO2, one of the most important absorbers. At this stage we do not address cloud formation and aerosol opacity. Estimated luminosities for post-impact planets, although lower than predicted by previous <span class="hlt">models</span>, show that the hottest post-giant-impact planets will be detectable with the planned 30 m-class telescopes. Finally, we use the <span class="hlt">models</span> to describe the cooling of a post-impact terrestrial planet and briefly investigate its time evolution, which ends as the planet transitions into a more conventional steam <span class="hlt">atmosphere</span> runaway greenhouse. This calculation brings a significant improvement over previous runaway greenhouse <span class="hlt">models</span>, by including additional opacity sources and comprehensive line lists for H2O and CO2. We find that the cooling timescale for post-giant impact Earths ranges between about 10^5 and 10^6 years, where the slower cooling is associated with the planet going through a runaway greenhouse stage.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GMD.....9.3123K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GMD.....9.3123K"><span>D-region ion-neutral coupled chemistry (Sodankylä Ion Chemistry, SIC) within the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM 4) - WACCM-SIC and WACCM-rSIC</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kovács, Tamás; Plane, John M. C.; Feng, Wuhu; Nagy, Tibor; Chipperfield, Martyn P.; Verronen, Pekka T.; Andersson, Monika E.; Newnham, David A.; Clilverd, Mark A.; Marsh, Daniel R.</p> <p>2016-09-01</p> <p>This study presents a new ion-neutral chemical <span class="hlt">model</span> coupled into the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM). The ionospheric D-region (altitudes ˜ 50-90 km) chemistry is based on the Sodankylä Ion Chemistry (SIC) <span class="hlt">model</span>, a one-dimensional <span class="hlt">model</span> containing 307 ion-neutral and ion recombination, 16 photodissociation and 7 photoionization reactions of neutral species, positive and negative ions, and electrons. The SIC mechanism was reduced using the simulation error minimization connectivity method (SEM-CM) to produce a reaction scheme of 181 ion-molecule reactions of 181 ion-molecule reactions of 27 positive and 18 negative ions. This scheme describes the concentration profiles at altitudes between 20 km and 120 km of a set of major neutral species (HNO3, O3, H2O2, NO, NO2, HO2, OH, N2O5) and ions (O2+, O4+, NO+, NO+(H2O), O2+(H2O), H+(H2O), H+(H2O)2, H+(H2O)3, H+(H2O)4, O3-, NO2-, O-, O2, OH-, O2-(H2O), O2-(H2O)2, O4-, CO3-, CO3-(H2O), CO4-, HCO3-, NO2-, NO3-, NO3-(H2O), NO3-(H2O)2, NO3-(HNO3), NO3-(HNO3)2, Cl-, ClO-), which agree with the full SIC mechanism within a 5 % tolerance. Four 3-D <span class="hlt">model</span> simulations were then performed, using the impact of the January 2005 solar proton event (SPE) on D-region HOx and NOx chemistry as a test case of four different <span class="hlt">model</span> versions: the standard WACCM (no negative ions and a very limited set of positive ions); WACCM-SIC (standard WACCM with the full SIC chemistry of positive and negative ions); WACCM-D (standard WACCM with a heuristic reduction of the SIC chemistry, recently used to examine HNO3 formation following an SPE); and WACCM-rSIC (standard WACCM with a reduction of SIC chemistry using the SEM-CM method). The standard WACCM misses the HNO3 enhancement during the SPE, while the full and reduced <span class="hlt">model</span> versions predict significant NOx, HOx and HNO3 enhancements in the mesosphere during solar proton events. The SEM-CM reduction also identifies the important ion-molecule reactions that affect the partitioning of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/924189','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/924189"><span><span class="hlt">Atmospheric</span> Climate <span class="hlt">Model</span> Experiments Performed at Multiple Horizontal Resolutions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Phillips, T; Bala, G; Gleckler, P; Lobell, D; Mirin, A; Maxwell, R; Rotman, D</p> <p>2007-12-21</p> <p>This report documents salient features of version 3.3 of the <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (CAM3.3) and of three climate simulations in which the resolution of its latitude-longitude grid was systematically increased. For all these simulations of global <span class="hlt">atmospheric</span> climate during the period 1980-1999, observed monthly ocean surface temperatures and sea ice extents were prescribed according to standard <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Intercomparison Project (AMIP) values. These CAM3.3 resolution experiments served as control runs for subsequent simulations of the climatic effects of agricultural irrigation, the focus of a Laboratory Directed Research and Development (LDRD) project. The CAM3.3 <span class="hlt">model</span> was able to replicate basic features of the historical climate, although biases in a number of <span class="hlt">atmospheric</span> variables were evident. Increasing horizontal resolution also generally failed to ameliorate the large-scale errors in most of the climate variables that could be compared with observations. A notable exception was the simulation of precipitation, which incrementally improved with increasing resolution, especially in regions where orography plays a central role in determining the local hydroclimate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800037595&hterms=Fischbein&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DFischbein','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800037595&hterms=Fischbein&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DFischbein"><span>High-resolution Martian <span class="hlt">atmosphere</span> <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Egan, W. G.; Fischbein, W. L.; Smith, L. L.; Hilgeman, T.</p> <p>1980-01-01</p> <p>A multilayer radiative transfer, high-spectral-resolution infrared <span class="hlt">model</span> of the lower <span class="hlt">atmosphere</span> of Mars has been constructed to assess the effect of scattering on line profiles. The <span class="hlt">model</span> takes into accout aerosol scattering and absorption and includes a line-by-line treatment of scattering and absorption by CO2 and H2O. The aerosol complex indices of refraction used were those measured on montmorillonite and basalt chosen on the basis of Mars ir data from the NASA Lear Airborne Observatory. The particle sizes and distribution were estimated using Viking data. The molecular line treatment employs the AFGL line parameters and Voigt profiles. The <span class="hlt">modeling</span> results indicate that the line profiles are only slightly affected by normal aerosol scattering and absorption, but the effect could be appreciable for heavy loading. The technique described permits a quantitative approach to assessing and correcting for the effect of aerosols on lineshapes in planetary <span class="hlt">atmospheres</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008581','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008581"><span>Validation of Space Weather <span class="hlt">Models</span> at <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kuznetsova, M. M.; Hesse, M.; Pulkkinen, A.; Maddox, M.; Rastaetter, L.; Berrios, D.; Zheng, Y.; MacNeice, P. J.; Shim, J.; Taktakishvili, A.; Chulaki, A.</p> <p>2011-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership to support the research and developmental work necessary to substantially increase space weather <span class="hlt">modeling</span> capabilities and to facilitate advanced <span class="hlt">models</span> deployment in forecasting operations. Space weather <span class="hlt">models</span> and coupled <span class="hlt">model</span> chains hosted at the CCMC range from the solar corona to the Earth's upper <span class="hlt">atmosphere</span>. CCMC has developed a number of real-time <span class="hlt">modeling</span> systems, as well as a large number of <span class="hlt">modeling</span> and data products tailored to address the space weather needs of NASA's robotic missions. The CCMC conducts unbiased <span class="hlt">model</span> testing and validation and evaluates <span class="hlt">model</span> readiness for operational environment. CCMC has been leading recent comprehensive <span class="hlt">modeling</span> challenges under GEM, CEDAR and SHINE programs. The presentation will focus on experience in carrying out comprehensive and systematic validation of large sets of. space weather <span class="hlt">models</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G11A0902B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G11A0902B"><span>IAG working group - Integration of GNSS <span class="hlt">atmosphere</span> <span class="hlt">models</span> with NWP <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bosy, J.; Vedel, H.; Hadas, T.</p> <p>2012-12-01</p> <p>Global Navigation Satellite Systems (GNSS) are designed for positioning, navigation and amongst other possible applications it can also be used for derive information about the state of the <span class="hlt">atmosphere</span>. The GNSS tropospheric products has been used in meteorology for several years, but they are still not widely used. Currently conducted studies aimed at integration of NWP <span class="hlt">models</span> and coordination between the meteorological and geodetic <span class="hlt">communities</span>. For this reason, in the frame of International Association of Geodesy in Sub-Commission SC 4.3 - Remote sensing and <span class="hlt">modeling</span> of the <span class="hlt">atmosphere</span> was established the working group WG4.3.3 Integration of GNSS <span class="hlt">atmosphere</span> <span class="hlt">models</span> with NWP <span class="hlt">models</span> The main objective of this Working Group is to study of integration of GNSS <span class="hlt">atmosphere</span> <span class="hlt">models</span> with Numerical Weather Prediction (NWP) <span class="hlt">models</span> for positioning and meteorological applications. It includes the assimilation of GNSS data processing products in NWP <span class="hlt">models</span>, the use of NWP <span class="hlt">models</span> in real-time positioning methods: RTK and PPP, the validation and comparison of different of GNSS <span class="hlt">atmosphere</span> <span class="hlt">models</span> using NWP outputs, investigation on new mapping functions based on the high resolution integrated <span class="hlt">models</span> of the troposphere, and the real time water vapor <span class="hlt">models</span> from GNSS data and NWP <span class="hlt">models</span> outputs. The paper presents the current state of activities of IAG WG4.3.3 members and future plans of joint researches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2254967R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2254967R"><span>Atomic Oscillator Strengths for Stellar <span class="hlt">Atmosphere</span> <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruffoni, Matthew; Pickering, Juliet C.</p> <p>2015-08-01</p> <p>In order to correctly <span class="hlt">model</span> stellar <span class="hlt">atmospheres</span>, fundamental atomic data must be available to describe atomic lines observed in their spectra. Accurate, laboratory-measured oscillator strengths (f-values) for Fe peak elements in neutral or low-ionisation states are particularly important for determining chemical abundances.However, advances in astronomical spectroscopy in recent decades have outpaced those in laboratory astrophysics, with the latter frequently being overlooked at the planning stages of new projects. As a result, numerous big-budget astronomy projects have been, and continue to be hindered by a lack of suitable, accurately-measured reference data to permit the analysis of expensive astronomical spectra; a problem only likely to worsen in the coming decades as spectrographs at new facilities increasingly move to infrared wavelengths.At Imperial College London - and in collaboration with NIST, Wisconsin University and Lund University - we have been working with the astronomy <span class="hlt">community</span> in an effort to provide new accurately-measured f-values for a range of projects. In particular, we have been working closely with the Gaia-ESO (GES) and SDSS-III/APOGEE surveys, both of which have discovered that many lines that would make ideal candidates for inclusion in their analyses have poorly defined f-values, or are simply absent from the database. Using high-resolution Fourier transform spectroscopy (R ~ 2,000,000) to provide atomic branching fractions, and combining these with level lifetimes measured with laser induced fluorescence, we have provided new laboratory-measured f-values for a range of Fe-peak elements, most recently including Fe I, Fe II, and V I. For strong, unblended lines, uncertainties are as low as ±0.02 dex.In this presentation, I will describe how experimental f-values are obtained in the laboratory and present our recent work for GES and APOGEE. In particular, I will also discuss the strengths and limitations of current laboratory</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28557350','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28557350"><span>Interactive effects of seasonal drought and elevated <span class="hlt">atmospheric</span> carbon dioxide concentration on prokaryotic rhizosphere <span class="hlt">communities</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Drigo, Barbara; Nielsen, Uffe N; Jeffries, Thomas C; Curlevski, Nathalie J A; Singh, Brajesh K; Duursma, Remko A; Anderson, Ian C</p> <p>2017-08-01</p> <p>Global change <span class="hlt">models</span> indicate that rainfall patterns are likely to shift towards more extreme events concurrent with increasing <span class="hlt">atmospheric</span> carbon dioxide concentration ([CO2 ]). Both changes in [CO2 ] and rainfall regime are known to impact above- and belowground <span class="hlt">communities</span>, but the interactive effects of these global change drivers have not been well explored, particularly belowground. In this experimental study, we examined the effects of elevated [CO2 ] (ambient + 240 ppm; [eCO2 ]) and changes in rainfall patterns (seasonal drought) on soil microbial <span class="hlt">communities</span> associated with forest ecosystems. Our results show that bacterial and archaeal <span class="hlt">communities</span> are highly resistant to seasonal drought under ambient [CO2 ]. However, substantial taxa specific responses to seasonal drought were observed at [eCO2 ], suggesting that [eCO2 ] compromise the resistance of microbial <span class="hlt">communities</span> to extreme events. Within the microbial <span class="hlt">community</span> we were able to identify three types of taxa specific responses to drought: tolerance, resilience and sensitivity that contributed to this pattern. All taxa were tolerant to seasonal drought at [aCO2 ], whereas resilience and sensitivity to seasonal drought were much greater in [eCO2 ]. These results provide strong evidence that [eCO2 ] moderates soil microbial <span class="hlt">community</span> responses to drought in forests, with potential implications for their long-term persistence and ecosystem functioning. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780030672&hterms=tornadoes+occur&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dtornadoes%2Boccur','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780030672&hterms=tornadoes+occur&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dtornadoes%2Boccur"><span><span class="hlt">Models</span> for some aspects of <span class="hlt">atmospheric</span> vortices</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Deissler, R. G.</p> <p>1977-01-01</p> <p>A frictionless adiabatic <span class="hlt">model</span> is used to study the growth of random vortices in an <span class="hlt">atmosphere</span> with buoyant instability and vertical wind shear, taking account of the effects of axial drag, heat transfer and precipitation-induced downdrafts. It is found that downdrafts of tornadic magnitude may occur in negatively buoyant columns. The radial-inflow velocity required to maintain a given maximum tangential velocity in a tornado is determined by using a turbulent vortex <span class="hlt">model</span>. A tornado <span class="hlt">model</span> which involves a rotating parent cloud as well as buoyancy and precipitation effects is also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000GMS...114..139S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000GMS...114..139S"><span>Nonlinear Kalman filters for <span class="hlt">atmospheric</span> chemistry <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Segers, Arjo; Heemink, Arnold; Verlaan, Martin; van Loon, Maarten</p> <p></p> <p>Four non linear Kaiman filter implementations are applied to an <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span>. The type of non linear dynamics present in such a <span class="hlt">model</span> complicates an accurate forecast of the state of the system. Therefore, different non linear forecast methods are applied as part of the Reduced Rank Square Root formulation of the Kaiman filter, either based on ensemble statistics or on linearizations. A filter based on minimal exact sampling proves to produce an accurate forecast of state and covariance, using only a few <span class="hlt">model</span> evaluations. Ensemble statistics are able to produce even more accurate results, but with the cost of at least a double amount of computation time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/231452','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/231452"><span>Parallel computing in <span class="hlt">atmospheric</span> chemistry <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rotman, D.</p> <p>1996-02-01</p> <p>Studies of <span class="hlt">atmospheric</span> chemistry are of high scientific interest, involve computations that are complex and intense, and require enormous amounts of I/O. Current supercomputer computational capabilities are limiting the studies of stratospheric and tropospheric chemistry and will certainly not be able to handle the upcoming coupled chemistry/climate <span class="hlt">models</span>. To enable such calculations, the authors have developed a computing framework that allows computations on a wide range of computational platforms, including massively parallel machines. Because of the fast paced changes in this field, the <span class="hlt">modeling</span> framework and scientific modules have been developed to be highly portable and efficient. Here, the authors present the important features of the framework and focus on the <span class="hlt">atmospheric</span> chemistry module, named IMPACT, and its capabilities. Applications of IMPACT to aircraft studies will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA346253','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA346253"><span>Development of <span class="hlt">Atmospheric</span> Infrared Emission <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2007-11-02</p> <p>spectral radiance may be calculated for an arbitrary line -of-sight (LOS) passing through up to seven profiles . Interpolation is used to... Spectral Line with the Voigt Profile ," J. Quant. Spectrosc. Radiat. Transfer, 14, 319 (1974). 34. "U. S. Standard <span class="hlt">Atmosphere</span> 1976," National Oceanic... Spectral Radiance <span class="hlt">Model</span> 7 2.4.1 Calculation for a Single Line 7 2.4.2 Illustrative Calculations 9 2.5 Data Comparisons 11 3. DEVELOPMENT OF</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Lean+AND+Service&pg=7&id=ED151052','ERIC'); return false;" href="https://eric.ed.gov/?q=Lean+AND+Service&pg=7&id=ED151052"><span>Governance: A <span class="hlt">Community</span> College <span class="hlt">Model</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Carhart, John I.; Collins, Charles C.</p> <p></p> <p>The purpose of this report is to describe the development of the input/output governance <span class="hlt">model</span> at Los Medanos College and to explore the governance issues pertinent to all <span class="hlt">community</span> colleges. Considerations in creating the <span class="hlt">model</span> included the issue of authority and responsibility in terms of legal sources, the authority and accountability…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.........6L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.........6L"><span>Observations and <span class="hlt">Modeling</span> of Tropical Planetary <span class="hlt">Atmospheres</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Laraia, Anne</p> <p>2016-01-01</p> <p>This thesis is a comprised of three different projects within the topic of tropical <span class="hlt">atmospheric</span> dynamics. First, I analyze observations of thermal radiation from Saturn's <span class="hlt">atmosphere</span> and from them, determine the latitudinal distribution of ammonia vapor near the 1.5-bar pressure level. The most prominent feature of the observations is the high brightness temperature of Saturn's subtropical latitudes on either side of the equator. After comparing the observations to a microwave radiative transfer <span class="hlt">model</span>, I find that these subtropical bands require very low ammonia relative humidity below the ammonia cloud layer in order to achieve the high brightness temperatures observed. We suggest that these bright subtropical bands represent dry zones created by a meridionally overturning circulation. Second, I use a dry <span class="hlt">atmospheric</span> general circulation <span class="hlt">model</span> to study equatorial superrotation in terrestrial <span class="hlt">atmospheres</span>. A wide range of <span class="hlt">atmospheres</span> are simulated by varying three parameters: the pole-equator radiative equilibrium temperature contrast, the convective lapse rate, and the planetary rotation rate. A scaling theory is developed that establishes conditions under which superrotation occurs in terrestrial <span class="hlt">atmospheres</span>. The scaling arguments show that superrotation is favored when the off-equatorial baroclinicity and planetary rotation rates are low. Similarly, superrotation is favored when the convective heating strengthens, which may account for the superrotation seen in extreme global-warming simulations. Third, I use a moist slab-ocean general circulation <span class="hlt">model</span> to study the impact of a zonally-symmetric continent on the distribution of monsoonal precipitation. I show that adding a hemispheric asymmetry in surface heat capacity is sufficient to cause symmetry breaking in both the spatial and temporal distribution of precipitation. This spatial symmetry breaking can be understood from a large-scale energetic perspective, while the temporal symmetry breaking requires</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JCli...14.3017L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JCli...14.3017L"><span>Seasonal Predictability in a <span class="hlt">Model</span> <span class="hlt">Atmosphere</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Hai</p> <p>2001-07-01</p> <p>The predictability of <span class="hlt">atmospheric</span> mean-seasonal conditions in the absence of externally varying forcing is examined. A perfect-<span class="hlt">model</span> approach is adopted, in which a global T21 three-level quasigeostrophic <span class="hlt">atmospheric</span> <span class="hlt">model</span> is integrated over 21 000 days to obtain a reference <span class="hlt">atmospheric</span> orbit. The <span class="hlt">model</span> is driven by a time-independent forcing, so that the only source of time variability is the internal dynamics. The forcing is set to perpetual winter conditions in the Northern Hemisphere (NH) and perpetual summer in the Southern Hemisphere.A significant temporal variability in the NH 90-day mean states is observed. The component of that variability associated with the higher-frequency motions, or climate noise, is estimated using a method developed by Madden. In the polar region, and to a lesser extent in the midlatitudes, the temporal variance of the winter means is significantly greater than the climate noise, suggesting some potential predictability in those regions.Forecast experiments are performed to see whether the presence of variance in the 90-day mean states that is in excess of the climate noise leads to some skill in the prediction of these states. Ensemble forecast experiments with nine members starting from slightly different initial conditions are performed for 200 different 90-day means along the reference <span class="hlt">atmospheric</span> orbit. The serial correlation between the ensemble means and the reference orbit shows that there is skill in the 90-day mean predictions. The skill is concentrated in those regions of the NH that have the largest variance in excess of the climate noise. An EOF analysis shows that nearly all the predictive skill in the seasonal means is associated with one mode of variability with a strong axisymmetric component.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JApMe..36.1076A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JApMe..36.1076A"><span>VALDRIFT--A Valley <span class="hlt">Atmospheric</span> Dispersion <span class="hlt">Model</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allwine, K. Jerry; Bian, Xindi; Whiteman, C. David; Thistle, Harold W.</p> <p>1997-08-01</p> <p>VALDRIFT (valley drift) is a valley <span class="hlt">atmospheric</span> transport, diffusion, and deposition <span class="hlt">model</span>. The <span class="hlt">model</span> is phenomenological-that is, the dominant meteorological processes governing the behavior of the valley <span class="hlt">atmosphere</span> are formulated explicitly in the <span class="hlt">model</span>, although in a highly parameterized fashion. The key meteorological processes treated are 1) nonsteady and nonhomogeneous along-valley winds and turbulent diffusivities, 2) convective boundary layer growth, 3) inversion descent, and 4) nocturnal temperature inversion breakup. The <span class="hlt">model</span> is applicable under relatively cloud-free, undisturbed synoptic conditions in which the winds in the valley are predominantly along the valley's axis. The <span class="hlt">model</span> is configured to operate through one diurnal cycle for a single narrow valley. The inputs required are the valley topographic characteristics, pollutant release rate as a function of time and space, wind speed and direction as functions of time measured at one height, lateral and vertical turbulent eddy diffusivities as functions of stability, and the valley temperature inversion characteristics at sunrise. The outputs are three-dimensional concentration fields and ground-level deposition fields as functions of time. The scientific foundations of VALDRIFT are given in this paper along with a brief discussion of the <span class="hlt">model</span> inputs and outputs. Air concentrations estimated by VALDRIFT compare favorably with results from a tracer experiment conducted in a deep mountain valley.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740012379','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740012379"><span>Organic chemistry in the <span class="hlt">atmosphere</span>. [laboratory <span class="hlt">modeling</span> of Titan <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sagan, C.</p> <p>1974-01-01</p> <p>The existence of an at least moderately complex organic chemistry on Titan is stipulated based on clear evidence of methane, and at least presumptive evidence of hydrogen in its <span class="hlt">atmosphere</span>. The ratio of methane to hydrogen is the highest of any <span class="hlt">atmosphere</span> in the solar system. Irradiation of hydrogen/methane mixtures produces aromatic and aliphatic hydrocarbons. A very reasonable hypothesis assumes that the red cloud cover of Titan is made of organic chemicals. Two-carbon hydrocarbons experimentally produced from irradiated mixtures of methane, ammonia, water, and hydrogen bear out the possible organic chemistry of the Titanian environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140016720','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140016720"><span><span class="hlt">Modeling</span> of Revitalization of <span class="hlt">Atmospheric</span> Water</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coker, Robert; Knox, Jim</p> <p>2014-01-01</p> <p>The <span class="hlt">Atmosphere</span> Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and <span class="hlt">modeling</span> of the water desiccant subsystem of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive <span class="hlt">model</span> of CDRA to guide system optimization and development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017LPICo2022.8013P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017LPICo2022.8013P"><span><span class="hlt">Modeling</span> Venus' <span class="hlt">Atmosphere</span> at Cloud Altitudes with a New Middle <span class="hlt">Atmosphere</span> GCM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parish, H. F.; Mitchell, J. L.</p> <p>2017-05-01</p> <p>We discuss simulations using a new Venus Middle <span class="hlt">atmosphere</span> <span class="hlt">Model</span> (VMM), which simulates the <span class="hlt">atmosphere</span> from just below the cloud deck to around 100 km altitude, with the aim of focusing on the dynamics at cloud levels and above.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008LPICo1447.9098S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008LPICo1447.9098S"><span>GRS Measurements of Mars' <span class="hlt">Atmospheric</span> Argon: Effects of Updated Mars <span class="hlt">Model</span> <span class="hlt">Atmospheres</span> on Concentration Computations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sprague, A. L.; Boynton, W. V.; Colaprete, A.; Janes, D. M.; Metzger, A. E.; Kerry, K. E.; Forget, F.; Starr, R.; Haberle, R. M.</p> <p>2008-11-01</p> <p>Mars' <span class="hlt">atmospheric</span> Ar concentrations for seasonal and geographically resolved measurements by the GRS on Mars Odyssey are discussed. No GCM has reproduced the Ar results - we will show new analyses using upgraded GCM <span class="hlt">model</span> <span class="hlt">atmospheres</span> from NASA and LMD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910368L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910368L"><span>Generic <span class="hlt">atmospheric</span> correction <span class="hlt">models</span> for radar measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Zhenhong; Yu, Chen; Crippa, Paola; Penna, Nigel</p> <p>2017-04-01</p> <p><span class="hlt">Atmospheric</span> effects (especially the part due to tropospheric water vapour) represent one of the major error sources of repeat-pass Interferometric Synthetic Aperture Radar (InSAR), and limit the accuracy of InSAR derived surface displacements. The spatio-temporal variations of <span class="hlt">atmospheric</span> water vapour make it a challenge to measure small-amplitude surface displacements with InSAR. In previous studies, several InSAR <span class="hlt">atmospheric</span> correction <span class="hlt">models</span> have been successfully demonstrated: (1) Ground-based correction <span class="hlt">models</span> such as those using Global Navigation Satellite System (GNSS) and/or surface meteorological observations, (2) Space-based correction <span class="hlt">models</span> including those involving NASA Moderate Resolution Imaging Spectroradiometer (MODIS) and/or ESA Medium Resolution Imaging Spectrometer (MERIS), and (3) Numerical Weather <span class="hlt">Model</span> (NWM) based corrections including those using the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim and/or Weather Research and Forecasting (WRF) <span class="hlt">models</span>. Each <span class="hlt">model</span> has its own inherited limitations. For example, ground-based correction <span class="hlt">models</span> are limited by the availability (and distribution) of ground observations, whilst MODIS/MERIS correction <span class="hlt">models</span> are sensitive to the presence of clouds and there is often a time difference between space-based water vapour and radar observations. Similar to space-based correction <span class="hlt">models</span>, NWM correction <span class="hlt">models</span> might be impacted by the time difference between NWM and radar observations. Taking into account the inherent advantages and limitations of GNSS, MODIS and ECMWF water vapour products, we aim to develop a global and near-real-time mode InSAR <span class="hlt">atmospheric</span> correction <span class="hlt">model</span>. Tropospheric delays can be routinely retrieved from ground-based GNSS arrays in all-weather conditions and also in real-time. We develop an Iterative Tropospheric Decomposition (ITD) interpolation <span class="hlt">model</span> that decouples the GNSS-estimated total tropospheric delays into (i) a stratified component highly correlated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JChEd..77.1650P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JChEd..77.1650P"><span>Local <span class="hlt">Atmospheric</span> Chemistry and Ozone <span class="hlt">Model</span> (LACOM)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pirjola, Liisa</p> <p>2000-12-01</p> <p>LACOM (Local <span class="hlt">Atmospheric</span> Chemistry and Ozone <span class="hlt">Model</span>) is a chemistry box <span class="hlt">model</span> that can be applied to teaching and learning <span class="hlt">atmospheric</span> chemistry at high schools, especially GLOBE (Global Learning and Observations to Benefit the Environment) schools, and at universities. The program code is written in Fortran and can be run on a PC under Microsoft Windows 95 or Windows NT, in MS-DOS prompt or using MS-Excel 97. Commercial graphic programs are used for data analysis. Using LACOM as a tool, students learn about the chemical complexity of the troposphere, the importance of solar radiation and photochemistry, the significant influence of emissions and depositions of gases, and the impact of meteorological parameters. Special attention is paid to tropospheric ozone. LACOM is appropriate for (i) simulating main features of a particular day, (ii) understanding the coupling between individual parameters, and (iii) predicting impacts of environmental problems such as increased pollution and ozone depletion in the lower <span class="hlt">atmosphere</span>. As input the program needs meteorological data and information about local emissions. For the days simulated students can make environmental observations (e.g., daily minimum and maximum temperatures, and temperature, relative humidity, and cloudiness at noon) as GLOBE schools do continuously and use these data in the simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A21B0117C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A21B0117C"><span>Observation and <span class="hlt">Modeling</span> of <span class="hlt">Atmospheric</span> Peroxyformic Acid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Z.; Liang, H.; Huang, D.; Huang, L.; Wu, Q.; Wu, H.</p> <p>2015-12-01</p> <p>The existence and importance of peroxyformic acid (PFA) in the <span class="hlt">atmosphere</span> has been under controversy. We present here, for the first time, the observation data for PFA from four field measurements carried out in China. These data provided powerful evidence that PFA can stay in the <span class="hlt">atmosphere</span>, typically in dozens of pptv level. The relationship between PFA and other detected peroxides was examined. The results showed that PFA had a strong positive correlation with its homolog, peroxyacetic acid, due to their similar sources and sinks. Through an evaluation of PFA production and removal rates, we proposed that the reactions between peroxyformyl radical (HC(O)O2) and formaldehyde or the hydroperoxyl radical (HO2) were likely to be the major source and degradation into formic acid (FA) was likely to be the major sink for PFA. Based on a box <span class="hlt">model</span> evaluation, we proposed that the HC(O)O2 and PFA chemistry was a major source for FA under low NOx conditions. Furthermore, it is found that the impact of the HC(O)O2 and PFA chemistry on radical cycling was dependent on the yield of HC(O)O2 radical from HC(O) + O2 reaction. When this yield exceeded 50%, the HC(O)O2 and PFA chemistry should not be neglected for calculating the radical budget. To make clear the exact importance of HC(O)O2 and PFA chemistry in the <span class="hlt">atmosphere</span>, further kinetic, field and <span class="hlt">modeling</span> studies are required.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7686S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7686S"><span>An exploration of Saturn's <span class="hlt">atmospheric</span> dynamics with Global Climate <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Spiga, Aymeric; Guerlet, Sandrine; Indurain, Mikel; Meurdesoif, Yann; Millour, Ehouarn; Sylvestre, Mélody; Dubos, Thomas; Fouchet, Thierry</p> <p>2015-04-01</p> <p>A decade of Cassini observations has yielded a new vision on the dynamical phenomena in Saturn's troposphere and stratosphere. Several puzzling signatures (equatorial oscillations with a period of about half a Saturn year, interhemispheric circulations affecting the hydrocarbons' distribution, including possible effects of rings shadowing, sudden warming associated with the powerful 2010 Great White Spot) cannot be explained by current photochemical and radiative <span class="hlt">models</span>, which do not include dynamics. We therefore suspect that 1. the observed anomalies arise from large-scale dynamical circulations and 2. those large-scale dynamical motions are driven by <span class="hlt">atmospheric</span> waves, eddies, and convection, in other words fundamental mechanisms giving birth to, e.g., the Quasi-Biennal Oscillation and Brewer-Dobson circulation in the Earth's middle <span class="hlt">atmosphere</span>. We explore the plausibility of this scenario using our new Global Climate <span class="hlt">Modeling</span> (GCM) for Saturn. To build this <span class="hlt">model</span>, we firstly formulated dedicated physical parameterizations for Saturn's <span class="hlt">atmosphere</span>, with a particular emphasis on radiative computations (using a correlated-k radiative transfer <span class="hlt">model</span>, with radiative species and spectral discretization tailored for Saturn) aimed at both efficiency and accuracy, and validated them against existing Cassini observations. A second step consisted in coupling this radiative <span class="hlt">model</span> to an hydrodynamical solver to predict the three-dimensional evolution of Saturn's tropospheric and stratospheric flow. We will provide an analysis of the first results of those dynamical simulations, with a focus on the development of baroclinic and barotropic instability, on eddy vs. mean flow interactions, and how this could relate to the enigmatic signatures observed by Cassini. Preliminary high-resolution simulations with a new icosahedral dynamical solver adapted to high-performance computing will also be analyzed. Perspectives are twofold: firstly, broadening our fundamental knowledge of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930037281&hterms=Tra&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DTra','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930037281&hterms=Tra&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DTra"><span><span class="hlt">Model</span> <span class="hlt">atmospheres</span> - Tool for identifying interstellar features</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Frisch, P. C.; Slojkowski, S. E.; Rodriguez-Bell, T.; York, D.</p> <p>1993-01-01</p> <p><span class="hlt">Model</span> <span class="hlt">atmosphere</span> parameters are derived for 14 early A stars with rotation velocities, from optical spectra, in excess of 80 km/s. The <span class="hlt">models</span> are compared with IUE observations of the stars in regions where interstellar lines are expected. In general, with the assumption of solar abundances, excellent fits are obtained in regions longward of 2580 A, and accurate interstellar equivalent widths can be derived using <span class="hlt">models</span> to establish the continuum. The fits are poorer at shorter wavelengths, particularly at 2026-2062 A, where the stellar <span class="hlt">model</span> parameters seem inadequate. Features indicating mass flows are evident in stars with known infrared excesses. In gamma TrA, variability in the Mg II lines is seen over the 5-year interval of these data, and also over timescales as short as 26 days. The present technique should be useful in systematic studies of episodic mass flows in A stars and for stellar abundance studies, as well as interstellar features.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22280641','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22280641"><span><span class="hlt">Atmospheric</span> transmittance <span class="hlt">model</span> for photosynthetically active radiation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Paulescu, Marius; Stefu, Nicoleta; Gravila, Paul; Paulescu, Eugenia; Boata, Remus; Pacurar, Angel; Mares, Oana; Pop, Nicolina; Calinoiu, Delia</p> <p>2013-11-13</p> <p>A parametric <span class="hlt">model</span> of the <span class="hlt">atmospheric</span> transmittance in the PAR band is presented. The <span class="hlt">model</span> can be straightforwardly applied for calculating the beam, diffuse and global components of the PAR solar irradiance. The required inputs are: air pressure, ozone, water vapor and nitrogen dioxide column content, Ångström's turbidity coefficient and single scattering albedo. Comparison with other <span class="hlt">models</span> and ground measured data shows a reasonable level of accuracy for this <span class="hlt">model</span>, making it suitable for practical applications. From the computational point of view the calculus is condensed into simple algebra which is a noticeable advantage. For users interested in speed-intensive computation of the effective PAR solar irradiance, a PC program based on the parametric equations along with a user guide are available online at http://solar.physics.uvt.ro/srms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.9505N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.9505N"><span>CIDGA - Coupling of Interior Dynamic <span class="hlt">models</span> with Global <span class="hlt">Atmosphere</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Noack, Lena; Plesa, Ana-Catalina; Breuer, Doris</p> <p>2010-05-01</p> <p><span class="hlt">Atmosphere</span> temperatures and in particular the surface temperatures mostly depend on the solar heat flux and the <span class="hlt">atmospheric</span> composition. The latter can be influenced by interior processes of the planet, i.e. volcanism that releases greenhouse gases such as H2O, CO2 and methane into the <span class="hlt">atmosphere</span> and plate tectonics through which <span class="hlt">atmospheric</span> CO2 is recycled via carbonates into the mantle. An increasing concentration of greenhouse gases in the <span class="hlt">atmosphere</span> results in an increase of the surface temperature. Changes in the surface temperature on the other hand may influence the cooling behaviour of the planet and hence influence its volcanic activity [Phillips et al., 2001]. This feedback relation between mantle convection and <span class="hlt">atmosphere</span> is not very well understood, since until now mostly either the interior dynamic of a planet or its <span class="hlt">atmosphere</span> was investigated separately. 2D or 3D mantle convection <span class="hlt">models</span> to the authors' knowledge haven't been coupled to the <span class="hlt">atmosphere</span> so far. We have used the 3D spherical simulation code GAIA [Hüttig et al., 2008] including partial melt production and coupled it with the <span class="hlt">atmosphere</span> module CIDGA using a gray greenhouse <span class="hlt">model</span> for varying H2O concentrations. This way, not only the influence of mantle dynamics on the <span class="hlt">atmosphere</span> can be investigated, but also the recoupling effect, that the surface temperature has on the mantle dynamics. So far, we consider one-plate planets without crustal and thus volatile recycling. Phillips et al. [2001] already investigated the coupling effect of the surface temperature on mantle dynamics by using simple parameterized convection <span class="hlt">models</span> for Venus. In their <span class="hlt">model</span> a positive feedback mechanism has been observed, i.e., an increase of the surface temperature leads to an increase of partial melt and hence an increase of <span class="hlt">atmosphere</span> density and surface temperature. Applying our <span class="hlt">model</span> to Venus, we show that an increase of surface temperature leads not only to an increase of partial melt in the mantle; it also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830012203','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830012203"><span>Jacchia-Lineberry upper <span class="hlt">atmosphere</span> density <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mueller, A. C.</p> <p>1982-01-01</p> <p>A series of increasingly accurate <span class="hlt">models</span> which are a careful blend of empirical and theoretical formulae were developed. The exospheric temperature is assumed to be a function of: (1) the average and daily variations in the solar flux, (2) the average and three hourly variations in the geomagnetic index, (3) the angle between the position vector and the axis of the unsymmetric <span class="hlt">atmospheric</span> bulge, and (4) the angle between the position vector and the geomagnetic pole. The exospheric temperature is related to the density by the solution of the diffusion equilibrium equations for the different constituents of the <span class="hlt">atmosphere</span> as a function of altitude. Other variations are <span class="hlt">modeled</span> directly as changes in the density. They are: (1) changes due to the semiannual effect, and (2) changes due to the seasonal latitudinal effect. The causes for these variations are not exactly known but may be <span class="hlt">modeled</span> sufficiently by empirical formulae. The Jacchia <span class="hlt">model</span> is assumed to be valid over the altitude range of 90 to 2500 km. The residuals between the observed density from satellite drag observations and the computed densities show the mean relative error to be generally less than 10 percent with occasional peak errors near 50 percent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3004717','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3004717"><span><span class="hlt">Community</span> Service <span class="hlt">Models</span> for Schizophrenia</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2005-01-01</p> <p>Schizophrenia is a chronic relapsing and remitting mental illness with lifetime prevalence between 0.40 to 1.4 percent. Most people with schizophrenia are treated in psychiatric units of local general hospitals for short periods of time when acutely ill. With the worldwide trend toward closure of asylums and institutions in the 1950s, there has been an increasing focus on treatment in the <span class="hlt">community</span>. <span class="hlt">Community</span> mental health teams (CMHT) are the kernel of <span class="hlt">community</span> treatment. Although their composition and modus operandi differ according to patient need, all <span class="hlt">models</span> claim superiority over outcomes of long inpatient stay. Case management, assertive outreach, and crisis resolution sometimes compete for resources. What is the evidence for their efficacy? What is the right mix of their use? As we discuss these, we propose that there may be room for the application of established industry <span class="hlt">models</span> of service delivery, such as Just-in-Time (JIT), in the treatment of patients with schizophrenia. PMID:21179632</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=199623&keyword=IC&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=85827413&CFTOKEN=25078809','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=199623&keyword=IC&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=85827413&CFTOKEN=25078809"><span>The Effect of Lateral Boundary Values on <span class="hlt">Atmospheric</span> Mercury Simulations with the CMAQ <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Simulation results from three global-scale <span class="hlt">models</span> of <span class="hlt">atmospheric</span> mercury have been used to define three sets of initial condition and boundary condition (IC/BC) data for regional-scale <span class="hlt">model</span> simulations over North America using the <span class="hlt">Community</span> Multi-scale Air Quality (CMAQ) <span class="hlt">model</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=199623&keyword=Book+AND+values&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=199623&keyword=Book+AND+values&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>The Effect of Lateral Boundary Values on <span class="hlt">Atmospheric</span> Mercury Simulations with the CMAQ <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Simulation results from three global-scale <span class="hlt">models</span> of <span class="hlt">atmospheric</span> mercury have been used to define three sets of initial condition and boundary condition (IC/BC) data for regional-scale <span class="hlt">model</span> simulations over North America using the <span class="hlt">Community</span> Multi-scale Air Quality (CMAQ) <span class="hlt">model</span>. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMPP13B1531B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMPP13B1531B"><span>New Data for Early Earth <span class="hlt">Atmospheric</span> <span class="hlt">Modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blackie, D.; Stark, G.; Lyons, J. R.; Pickering, J.; Smith, P. L.; Thorne, A.</p> <p>2010-12-01</p> <p>The timing of the oxygenation of the Earth’s <span class="hlt">atmosphere</span> is a central issue in understanding the Earth’s paleoclimate. The discovery of mass-independent fractionation (MIF) of sulphur isotopes deposited within Archean and Paleoproterozoic rock samples (> 2.4 Gyrs) and the transition to mass-dependent fractionation found in younger samples, could provide a marker for the rise in oxygen concentrations in the Earth’s <span class="hlt">atmosphere</span> [1]. Laboratory experiments [2; 3] suggest isotopic self shielding during gas phase photolysis of SO2 present at wavelengths shorter than 220 nm as the dominant mechanism for MIF. The UV absorption of SO2 is dominated by the C1B2-X1A1 electronic system which comprises strong vibrational bands extending from 170 - 230 nm. Within an <span class="hlt">atmosphere</span> consisting of low O2 and O3 concentrations, such as that predicted for the early Earth, UV radiation would penetrate deep into the ancient Earth’s <span class="hlt">atmosphere</span> in the 180 - 220 nm range driving the photolysis of SO2. We have conducted the first ever high resolution measurements of the photo absorption cross sections of several isotopologues of SO2, namely 32SO2, 33SO2, 34SO2 and 36SO2, using the Imperial College UV Fourier transform spectrometer [4] which is ideal for high resolution, broad-band, VIS/UV measurements. The cross sections are being measured at Imperial College at initial resolutions of 1.0 cm-1 which will be increased to resolutions < 0.5 cm-1 for inclusion in photochemical <span class="hlt">models</span> of the early Earth’s <span class="hlt">atmosphere</span> in order to more reliably interpret the sulphur isotope ratios found in ancient rock samples [5]. For discussion and interpretation of the photochemical <span class="hlt">models</span> see the abstract by Lyons et al.(this meeting). References [1] J. Farquhar and B.A. Wing. Earth and Planetary Science Letters, 213:1-13, 2003. [2] J. Farquhar, J. Savarino, S. Airieau, and M.H Thiemens. Journal of Geophysical Research,106:32829-32839, 2001. [3] A. Pen and R. N. Clayton.Geochimica et Cosmochimica Acta</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=328730&keyword=Salmon&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91087902&CFTOKEN=27381208','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=328730&keyword=Salmon&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91087902&CFTOKEN=27381208"><span>Nisqually <span class="hlt">Community</span> Forest VELMA <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>We developed a set of <span class="hlt">modeling</span> tools to support <span class="hlt">community</span>-based forest management and salmon-recovery planning in Pacific Northwest watersheds. Here we describe how these tools are being applied to the Mashel River Watershed in collaboration with the Board of Directors of the Nis...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=328730&keyword=forest+AND+carbon+AND+sequestration&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=328730&keyword=forest+AND+carbon+AND+sequestration&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Nisqually <span class="hlt">Community</span> Forest VELMA <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>We developed a set of <span class="hlt">modeling</span> tools to support <span class="hlt">community</span>-based forest management and salmon-recovery planning in Pacific Northwest watersheds. Here we describe how these tools are being applied to the Mashel River Watershed in collaboration with the Board of Directors of the Nis...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016sf2a.conf..223A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016sf2a.conf..223A"><span>The PHOENIX <span class="hlt">Model</span> <span class="hlt">Atmosphere</span> Grid for Stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allard, F.</p> <p>2016-12-01</p> <p>We present a new project for a 1D static though full NLTE <span class="hlt">model</span> <span class="hlt">atmosphere</span> grid ranging T_{eff}= 15,000 to 1500 K in 100K steps, surface gravities ranging from log g= -0.5 to 6.0 in steps of 0.25 dex, and metallicity ranging from [M/H]=-2.5 to +0.5 in steps of 0.25 dex accounting for alpha element enrichment of [α/H]= +0.0, +0.2, +0.4 and C/O enhancement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6710288','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6710288"><span>Mesoscale <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> for emergency response</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>O'Steen, B.L.; Fast, J.D.</p> <p>1992-01-01</p> <p><span class="hlt">Atmospheric</span> transport <span class="hlt">models</span> for emergency response have traditionally utilized meteorological fields interpolated from sparse data to predict contaminant transport. Often these fields are adjusted to satisfy constraints derived from the governing equations of geophysical fluid dynamics, e.g. mass continuity. Gaussian concentration distributions or stochastic <span class="hlt">models</span> are then used to represent turbulent diffusion of a contaminant in the diagnosed meteorological fields. The popularity of these <span class="hlt">models</span> derives from their relative simplicity, ability to make reasonable short-term predictions and, most important, execution speed. The ability to generate a transport prediction for an accidental release from the Savannah River Site in a time frame which will allow protective action to be taken is essential in an emergency response operation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10134723','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10134723"><span>Mesoscale <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> for emergency response</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>O`Steen, B.L.; Fast, J.D.</p> <p>1992-12-31</p> <p><span class="hlt">Atmospheric</span> transport <span class="hlt">models</span> for emergency response have traditionally utilized meteorological fields interpolated from sparse data to predict contaminant transport. Often these fields are adjusted to satisfy constraints derived from the governing equations of geophysical fluid dynamics, e.g. mass continuity. Gaussian concentration distributions or stochastic <span class="hlt">models</span> are then used to represent turbulent diffusion of a contaminant in the diagnosed meteorological fields. The popularity of these <span class="hlt">models</span> derives from their relative simplicity, ability to make reasonable short-term predictions and, most important, execution speed. The ability to generate a transport prediction for an accidental release from the Savannah River Site in a time frame which will allow protective action to be taken is essential in an emergency response operation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A33B0202T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A33B0202T"><span>A Moist Idealized Test Case for <span class="hlt">Atmospheric</span> General Circulation <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thatcher, D.; Jablonowski, C.; Zarzycki, C.</p> <p>2013-12-01</p> <p>The vast array of dynamical and physical processes within <span class="hlt">atmospheric</span> general circulation <span class="hlt">models</span> (GCMs) makes it difficult to correctly distinguish the sources of error within a <span class="hlt">model</span>. Therefore, simplified test cases are important in testing the accuracy of individual <span class="hlt">model</span> components, such as the fluid flow component in the dynamical core. Typically, dynamical cores are coupled to complex subgrid-scale physical parameterization packages, and the nonlinear interactions mask the causes and effects of <span class="hlt">atmospheric</span> phenomena. Idealized tests are a computationally efficient method for analyzing the underlying numerical techniques of dynamical cores. The newly proposed test case is based on the widely-used Held and Suarez (1994) (HS) test for dry dynamical cores. The latter replaces the full physical parameterization package with a Newtonian temperature relaxation and Rayleigh damping of low-level winds on a flat planet. However, the impact of moisture, a crucial physics-dynamics coupling process, is missing from the HS test. Here we present a moist variant of the HS test case to create a test case of intermediate complexity with idealized moisture feedbacks. It uses simplified physical processes to <span class="hlt">model</span> large-scale condensation, boundary layer turbulence, and surface fluxes of horizontal momentum, latent heat, and sensible heat between the <span class="hlt">atmosphere</span> and an ocean-covered planet (Reed and Jablonowski, 2012). We apply this test to four dynamical cores within NCAR's <span class="hlt">Community</span> <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 5.3, including the Finite Volume, Eulerian spectral transform, semi-Lagrangian spectral transform, and Spectral Element dynamical cores. We analyze the kinetic energy spectra, general circulation, and precipitation of this new moist idealized test case across all four dynamical cores. Simulations of the moist idealized test case are compared to aqua-planet experiments with complex physical parameterizations. The moist idealized test case successfully reproduces many features</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004JCli...17.1004B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004JCli...17.1004B"><span>Dynamic Stabilization of <span class="hlt">Atmospheric</span> Single Column <span class="hlt">Models</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bergman, John W.; Sardeshmukh, Prashant D.</p> <p>2004-03-01</p> <p>Single column <span class="hlt">models</span> (SCMs) provide an economical framework for assessing the sensitivity of <span class="hlt">atmospheric</span> temperature and humidity to natural and imposed perturbations, and also for developing improved representations of diabatic processes in weather and climate <span class="hlt">models</span>. Their economy is achieved at the expense of ignoring interactions with the circulation dynamics; thus, advection by the large-scale flow is either prescribed or neglected. This artificial decoupling of the diabatic and adiabatic tendencies can often cause rapid error growth in SCM integrations, especially in the Tropics where large-scale vertical advection is important. As a result, SCMs can quickly develop highly unrealistic thermodynamic structures, making it pointless to study their subsequent evolution.This paper suggests one way around this fundamental difficulty through a simple coupling of the diabatic and adiabatic tendencies. In essence, the local vertical velocity at any instant is specified by a formula that links the local vertical temperature advection to the evolution of SCM-generated diabatic heating rates up to that instant. This vertical velocity is then used to determine vertical humidity advection, and also horizontal temperature and humidity advection under an additional assumption that the column is embedded in a uniform environment. The parameters in the formula are estimated in a separate set of calculations, from the approach to equilibrium of a linearized global primitive equation <span class="hlt">model</span> forced by steady heat sources. As a test, the parameterized dynamics are used to predict the linear <span class="hlt">model</span>'s local response to oscillating heat sources, and found to perform remarkably well over a wide range of space and time scales. In a second test, the parameterization is found to capture important aspects of a general circulation <span class="hlt">model</span>'s vertical advection and temperature tendencies and their lead lag relationships with diabatic heating fluctuations at convectively active locations in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....4984B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....4984B"><span>Towards a <span class="hlt">community</span> Earth System <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blackmon, M.</p> <p>2003-04-01</p> <p>The <span class="hlt">Community</span> Climate System <span class="hlt">Model</span>, version 2 (CCSM2), was released in June 2002. CCSM2 has several new components and features, which I will discuss briefly. I will also show a few results from a multi-century equilibrium run with this <span class="hlt">model</span>, emphasizing the improvements over the earlier simulation using the original CSM. A few flaws and inadequacies in CCSM2 have been identified. I will also discuss briefly work underway to improve the <span class="hlt">model</span> and present results, if available. CCSM2, with improvements, will be the basis for the development of a <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM). The highest priority for expansion of the <span class="hlt">model</span> involves incorporation of biogeosciences into the coupled <span class="hlt">model</span> system, with emphasis given to the carbon, nitrogen and iron cycles. The overall goal of the biogeosciences project within CESM is to understand the regulation of planetary energetics, planetary ecology, and planetary metabolism through exchanges of energy, momentum, and materials among <span class="hlt">atmosphere</span>, land, and ocean, and the response of the climate system through these processes to changes in land cover and land use. In particular, this research addresses how biogeochemical coupling of carbon, nitrogen, and iron cycles affects climate and how human perturbations of these cycles alter climate. To accomplish these goals, the <span class="hlt">Community</span> Land <span class="hlt">Model</span>, the land component of CCSM2, is being developed to include river routing, carbon and nitrogen cycles, emissions of mineral aerosols and biogenic volatile organic compounds, dry deposition of various gases, and vegetation dynamics. The carbon and nitrogen cycles are being implemented using parameterizations developed as part of a state-of-the-art ecosystem biogeochemistry <span class="hlt">model</span>. The primary goal of this research is to provide an accurate net flux of CO2 between the land and the <span class="hlt">atmosphere</span> so that CESM can be used to study the dynamics of the coupled climate-carbon system. Emissions of biogenic volatile organic compounds are also based on a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15005971','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15005971"><span>PCMDI analysis of candidate <span class="hlt">atmospheric</span> <span class="hlt">models</span> for CCSM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wehner, M F; Taylor, K; Doutriaux, C; AchutaRao, K; Gleckler, P; Hnilo, J; Boyle, J</p> <p>2000-12-13</p> <p>This report is intended to give a summary analysis of the candidate <span class="hlt">model</span> configurations under consideration by NCAR for the <span class="hlt">atmospheric</span> component of next version of the <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> (CCSM). Intercomparison results are presented for each of the <span class="hlt">models</span> available prior to the <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Working Group (AMWG) meeting, December 12-14, 2000. We present four types of figures in this report. The traditional methods of viewing zonal mean surface fields, latitude-longitude maps and zonal mean latitude-height cross sections are straightforward. In each of these cases, we present DJF and JJA climatological averages and a difference from an observational or reanalysis data set. The fourth method of analyzing the candidates' <span class="hlt">model</span> performance involves the use of ''performance portraits'' and is explained in detail on following pages. As stated by NCAR and the AMWG, the information included in this report should be considered proprietary to NCAR and is not to be cited, consistent with the disclaimer on the AMWG password protected web pages. We deliberately have deferred our conclusions in this printed report to our presentation. Rather, we encourage you to draw your own conclusions based on these figures and other information made available at the AMWG meeting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1976H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1976H"><span>The <span class="hlt">Atmospheric</span> Radionuclide Transport <span class="hlt">Model</span> (ARTM) - Validation of a long-term <span class="hlt">atmospheric</span> dispersion <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hettrich, Sebastian; Wildermuth, Hans; Strobl, Christopher; Wenig, Mark</p> <p>2016-04-01</p> <p>In the last couple of years, the <span class="hlt">Atmospheric</span> Radionuclide Transport <span class="hlt">Model</span> (ARTM) has been developed by the German Federal Office for Radiation Protection (BfS) and the Society for Plant and Reactor Security (GRS). ARTM is an <span class="hlt">atmospheric</span> dispersion <span class="hlt">model</span> for continuous long-term releases of radionuclides into the <span class="hlt">atmosphere</span>, based on the Lagrangian particle <span class="hlt">model</span>. This <span class="hlt">model</span>, developed in the first place as a more realistic replacement for the out-dated Gaussian plume <span class="hlt">models</span>, is currently being optimised for further scientific purposes to study <span class="hlt">atmospheric</span> dispersion in short-range scenarios. It includes a diagnostic wind field <span class="hlt">model</span>, allows for the application of building structures and multiple sources (including linear, 2-and 3-dimensional source geometries), and considers orography and surface roughness. As an output it calculates the activity concentration, dry and wet deposition and can <span class="hlt">model</span> also the radioactive decay of Rn-222. As such, ARTM requires to undergo an intense validation process. While for short-term and short-range <span class="hlt">models</span>, which were mainly developed for examining nuclear accidents or explosions, a few measurement data-sets are available for validation, data-sets for validating long-term <span class="hlt">models</span> are very sparse and the existing ones mostly prove to be not applicable for validation. Here we present a strategy for the validation of long-term Lagrangian particle <span class="hlt">models</span> based on the work with ARTM. In our validation study, the first part we present is a comprehensive analysis of the <span class="hlt">model</span> sensitivities on different parameters like e.g. (simulation grid size resolution, starting random number, amount of simulation particles, etc.). This study provides a good estimation for the uncertainties of the simulation results and consequently can be used to generate <span class="hlt">model</span> outputs comparable to the available measurements data at various distances from the emission source. This comparison between measurement data from selected scenarios and simulation results</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75826&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75826&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span><span class="hlt">MODELS</span>-3 <span class="hlt">COMMUNITY</span> MULTISCALE AIR QUALITY (CMAQ) <span class="hlt">MODEL</span> AEROSOL COMPONENT 1: <span class="hlt">MODEL</span> DESCRIPTION</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The aerosol component of the <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">model</span> is designed to be an efficient and economical depiction of aerosol dynamics in the <span class="hlt">atmosphere</span>. The approach taken represents the particle size distribution as the superposition of three lognormal subdis...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75826&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90549710&CFTOKEN=81522402','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75826&keyword=photochemistry&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90549710&CFTOKEN=81522402"><span><span class="hlt">MODELS</span>-3 <span class="hlt">COMMUNITY</span> MULTISCALE AIR QUALITY (CMAQ) <span class="hlt">MODEL</span> AEROSOL COMPONENT 1: <span class="hlt">MODEL</span> DESCRIPTION</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The aerosol component of the <span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">model</span> is designed to be an efficient and economical depiction of aerosol dynamics in the <span class="hlt">atmosphere</span>. The approach taken represents the particle size distribution as the superposition of three lognormal subdis...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/air-research/atmospheric-model-evaluation-tool-meteorological-and-air-quality-simulations','PESTICIDES'); return false;" href="https://www.epa.gov/air-research/atmospheric-model-evaluation-tool-meteorological-and-air-quality-simulations"><span><span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Evaluation Tool for meteorological and air quality simulations</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>The <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Evaluation Tool compares <span class="hlt">model</span> predictions to observed data from various meteorological and air quality observation networks to help evaluate meteorological and air quality simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010069259','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010069259"><span>Comparing the Degree of Land-<span class="hlt">Atmosphere</span> Interaction in Four <span class="hlt">Atmospheric</span> General Circulation <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koster, Randal D.; Dirmeyer, Paul A.; Hahmann, Andrea N.; Ijpelaar, Ruben; Tyahla, Lori; Cox, Peter; Suarez, Max J.; Houser, Paul R. (Technical Monitor)</p> <p>2001-01-01</p> <p>Land-<span class="hlt">atmosphere</span> feedback, by which (for example) precipitation-induced moisture anomalies at the land surface affect the overlying <span class="hlt">atmosphere</span> and thereby the subsequent generation of precipitation, has been examined and quantified with many <span class="hlt">atmospheric</span> general circulation <span class="hlt">models</span> (AGCMs). Generally missing from such studies, however, is an indication of the extent to which the simulated feedback strength is <span class="hlt">model</span> dependent. Four <span class="hlt">modeling</span> groups have recently performed a highly controlled numerical experiment that allows an objective inter-<span class="hlt">model</span> comparison of land-<span class="hlt">atmosphere</span> feedback strength. The experiment essentially consists of an ensemble of simulations in which each member simulation artificially maintains the same time series of surface prognostic variables. Differences in <span class="hlt">atmospheric</span> behavior between the ensemble members then indicates the degree to which the state of the land surface controls <span class="hlt">atmospheric</span> processes in that <span class="hlt">model</span>. A comparison of the four sets of experimental results shows that feedback strength does indeed vary significantly between the AGCMs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1097328','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1097328"><span>The <span class="hlt">Community</span> Earth System <span class="hlt">Model</span>: A Framework for Collaborative Research</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hurrell, Jim; Holland, Marika M.; Gent, Peter R.; Ghan, Steven J.; Kay, Jennifer; Kushner, P.; Lamarque, J.-F.; Large, William G.; Lawrence, David M.; Lindsay, Keith; Lipscomb, William; Long , Matthew; Mahowald, N.; Marsh, D.; Neale, Richard; Rasch, Philip J.; Vavrus, Steven J.; Vertenstein, Mariana; Bader, David C.; Collins, William D.; Hack, James; Kiehl, J. T.; Marshall, Shawn</p> <p>2013-09-30</p> <p>The <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM) is a flexible and extensible <span class="hlt">community</span> tool used to investigate a diverse set of earth system interactions across multiple time and space scales. This global coupled <span class="hlt">model</span> is a natural evolution from its predecessor, the <span class="hlt">Community</span> Climate System <span class="hlt">Model</span>, following the incorporation of new earth system capabilities. These include the ability to simulate biogeochemical cycles, <span class="hlt">atmospheric</span> chemistry, ice sheets, and a high-top <span class="hlt">atmosphere</span>. These and other new <span class="hlt">model</span> capabilities are enabling investigations into a wide range of pressing scientific questions, providing new predictive capabilities and increasing our collective knowledge about the behavior and interactions of the earth system. Simulations with numerous configurations of the CESM have been provided to the Coupled <span class="hlt">Model</span> Intercomparison Project Phase 5 (CMIP5) and are being analyzed by the broader <span class="hlt">community</span> of scientists. Additionally, the <span class="hlt">model</span> source code and associated documentation are freely available to the scientific <span class="hlt">community</span> to use for earth system studies, making it a true <span class="hlt">community</span> tool. Here we describe this earth <span class="hlt">modeling</span> system, its various possible configurations, and illustrate its capabilities with a few science highlights.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120015335','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120015335"><span>Developments in <span class="hlt">Atmosphere</span> Revitalization <span class="hlt">Modeling</span> and Simulation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Knox, James C.; Kittredge, Kenneth; Xoker, Robert F.; Cummings, Ramona; Gomez, Carlos F.</p> <p>2012-01-01</p> <p>"NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated <span class="hlt">atmosphere</span> revitalization test. This paper describes the development of <span class="hlt">atmosphere</span> revitalization <span class="hlt">models</span> and simulations. A companion paper discusses the hardware design and sorbent screening and characterization effort in support of the <span class="hlt">Atmosphere</span> Revitalization Recovery and Environmental Monitoring (ARREM) project within the AES program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA533812','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA533812"><span>Training <span class="hlt">Community</span> <span class="hlt">Modeling</span> and Simulation Business Plan: 2009 Edition</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-04-01</p> <p>HLA user <span class="hlt">community</span> • Develop Federate compliance test tools • Revise the HLA Object <span class="hlt">Model</span> Template ( OMT ) • Update the Distributed Simulation...Ocean, <span class="hlt">Atmosphere</span>, and Space Environmental Services OCONUS Outside of the Continental United States OFT Office of Force Transformation OMT Object</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED452008.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED452008.pdf"><span>Using the <span class="hlt">Community</span> Readiness <span class="hlt">Model</span> in Native <span class="hlt">Communities</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jumper-Thurman, Pamela; Plested, Barbara A.; Edwards, Ruth W.; Helm, Heather M.; Oetting, Eugene R.</p> <p></p> <p>The effects of alcohol and other drug abuse are recognized as a serious problem in U.S. <span class="hlt">communities</span>. Policy efforts and increased law enforcement have only a minimal impact if prevention strategies are not consistent with the <span class="hlt">community</span>'s level of readiness, are not culturally relevant, and are not <span class="hlt">community</span>-specific. A <span class="hlt">model</span> has been developed for…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=64968&keyword=aquatic+AND+exercises&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=89283693&CFTOKEN=27136050','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=64968&keyword=aquatic+AND+exercises&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=89283693&CFTOKEN=27136050"><span>CURRENT METHODS AND RESEARCH STRATEGIES FOR <span class="hlt">MODELING</span> <span class="hlt">ATMOSPHERIC</span> MERCURY</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The <span class="hlt">atmospheric</span> pathway of the global mercury cycle is known to be the primary source of mercury contamination to most threatened aquatic ecosystems. Current efforts toward numerical <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> mercury are hindered by an incomplete understanding of emissions, atmosp...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=64968&keyword=total+AND+physical+AND+response&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=64968&keyword=total+AND+physical+AND+response&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>CURRENT METHODS AND RESEARCH STRATEGIES FOR <span class="hlt">MODELING</span> <span class="hlt">ATMOSPHERIC</span> MERCURY</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The <span class="hlt">atmospheric</span> pathway of the global mercury cycle is known to be the primary source of mercury contamination to most threatened aquatic ecosystems. Current efforts toward numerical <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> mercury are hindered by an incomplete understanding of emissions, atmosp...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740024152','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740024152"><span><span class="hlt">Model</span> <span class="hlt">atmospheres</span> for cool stars. [varying chemical composition</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, H. R.</p> <p>1974-01-01</p> <p>This report contains an extensive series of <span class="hlt">model</span> <span class="hlt">atmospheres</span> for cool stars having a wide range in chemical composition. <span class="hlt">Model</span> <span class="hlt">atmospheres</span> (temperature, pressure, density, etc.) are tabulated, along with emergent energy flux distributions, limb darkening, and information on convection for selected <span class="hlt">models</span>. The <span class="hlt">models</span> are calculated under the usual assumptions of hydrostatic equilibrium, constancy of total energy flux (including transport both by radiation and convection) and local thermodynamic equilibrium. Some molecular and atomic line opacity is accounted for as a straight mean. While cool star <span class="hlt">atmospheres</span> are regimes of complicated physical conditions, and these <span class="hlt">atmospheres</span> are necessarily approximate, they should be useful for a number of kinds of spectral and <span class="hlt">atmospheric</span> analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040006299','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040006299"><span>Radiation Belt Electron Dynamics: <span class="hlt">Modeling</span> <span class="hlt">Atmospheric</span> Losses</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Selesnick, R. S.</p> <p>2003-01-01</p> <p>The first year of work on this project has been completed. This report provides a summary of the progress made and the plan for the coming year. Also included with this report is a preprint of an article that was accepted for publication in Journal of Geophysical Research and describes in detail most of the results from the first year of effort. The goal for the first year was to develop a radiation belt electron <span class="hlt">model</span> for fitting to data from the SAMPEX and Polar satellites that would provide an empirical description of the electron losses into the upper <span class="hlt">atmosphere</span>. This was largely accomplished according to the original plan (with one exception being that, for reasons described below, the inclusion of the loss cone electrons in the <span class="hlt">model</span> was deferred). The main concerns at the start were to accurately represent the balance between pitch angle diffusion and eastward drift that determines the dominant features of the low altitude data, and then to accurately convert the <span class="hlt">model</span> into simulated data based on the characteristics of the particular electron detectors. Considerable effort was devoted to achieving these ends. Once the <span class="hlt">model</span> was providing accurate results it was applied to data sets selected from appropriate periods in 1997, 1998, and 1999. For each interval of -30 to 60 days, the <span class="hlt">model</span> parameters were calculated daily, thus providing good short and long term temporal resolution, and for a range of radial locations from L = 2.7 to 3.9. .</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH21A1816K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH21A1816K"><span>Lithosphere-<span class="hlt">Atmosphere</span>-Ionosphere coupling <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kachakhidze, M. K., III</p> <p>2015-12-01</p> <p>The present work offers interpretation of a mechanism of formation of hypothetic ideal electromagnetic contour, creation of which is envisaged in incoming earthquake focal zone. <span class="hlt">Model</span> of generation of EM emissions detected before earthquake is based on physical analogues of distributed and conservative systems and focal zones. According to the <span class="hlt">model</span> the process of earthquake preparation from the moment of appearance of cracks in the system, including completion of series of foreshocks, earthquake and aftershocks, are entirely explained by oscillating systems.According to the authors of the work electromagnetic emissions in radio diapason is more universal and reliable than other anomalous variations of various geophysical phenomena in earthquake preparation period; Besides, VLF/LF electromagnetic emissions might be declared as the main precursor of earthquake because it might turn out very useful with the view of prediction of large (M5) inland earthquakes and to govern processes going on in lithosphere-<span class="hlt">atmosphere</span>-ionosphere coupling (LAIC) system. Based on this <span class="hlt">model</span>, in case of electromagnetic emissions spectrum monitoring in the period that precedes earthquake it is possible to determine, with certain accuracy, the time, location and magnitude of an incoming earthquake simultaneously.The present item considers possible physical mechanisms of the geophysical phenomena, which may accompany earthquake preparation process and expose themselves several months, weeks or days prior to earthquakes. Such as: Changing of intensity of electro-telluric current in focal area; Perturbations of geomagnetic field in forms of irregular pulsations or regular short-period pulsations; Perturbations of <span class="hlt">atmospheric</span> electric field; Irregular changing of characteristic parameters of the lower ionosphere (plasma frequency, electron concentration, height of D layer, etc.); Irregular perturbations reaching the upper ionosphere, namely F2-layer, for 2-3 days before the earthquake</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920016126','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920016126"><span><span class="hlt">Modelling</span> <span class="hlt">atmospheric</span> scatterers using spacecraft observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rages, Kathy A.</p> <p>1992-01-01</p> <p>Voyager images of Triton indicate considerable spatial variability in the concentration of at least two different scattering components in the <span class="hlt">atmosphere</span>. Data from high phase angle limb scans were fit to Mie scattering <span class="hlt">models</span> to derive mean particle sizes, number densities, and vertical extent for both types of scattering material at ten different locations between 15 deg S and 70 deg S. These fits reveal a thin haze at latitudes equatorward of 25-30 deg S. The imaging data can be fit reasonably well by both conservatively scattering and absorbing hazes with particle sizes near 0.18 micron and optical depths of order 0.001-0.01. Rayleigh scattering haze fits the imaging data somewhat less well, and can be totally ruled out by combining the imaging and UVS measurements. At high southern latitudes, Triton displays clouds below an altitude of approximately 8 km, as well as the haze at higher altitudes. The clouds have particle sizes which may range from 0.7-2.0 microns, or may be near 0.25 micron. The <span class="hlt">atmospheric</span> optical depth poleward of 30 deg S must be generally greater than 0.1, but need not be more than 0.3. Horizontal inhomogeneities are quite noticeable, especially at longitudes east of (i.e., higher than) 180 deg.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..12012054L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..12012054L"><span>A global electric circuit <span class="hlt">model</span> within a <span class="hlt">community</span> climate <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lucas, G. M.; Baumgaertner, A. J. G.; Thayer, J. P.</p> <p>2015-12-01</p> <p>To determine the complex dependencies of currents and electric fields within the Global Electric Circuit (GEC) on the underlying physics of the <span class="hlt">atmosphere</span>, a new <span class="hlt">modeling</span> framework of the GEC has been developed for use within global circulation <span class="hlt">models</span>. Specifically, the <span class="hlt">Community</span> Earth System <span class="hlt">Modeling</span> framework has been utilized. A formulation of <span class="hlt">atmospheric</span> conductivity based on ion production and loss mechanisms (including galactic cosmic rays, radon, clouds, and aerosols), conduction current sources, and ionospheric potential changes due to the influence of external current systems are included. This paper presents a full description of the calculation of the electric fields and currents within the <span class="hlt">model</span>, which now includes several advancements to GEC <span class="hlt">modeling</span> as it incorporates many processes calculated individually in previous articles into a consistent <span class="hlt">modeling</span> framework. This framework uniquely incorporates effects from the troposphere up to the ionosphere within a single GEC <span class="hlt">model</span>. The incorporation of a magnetospheric potential, which is generated by a separate magnetospheric current system, acts to modulate or enhance the surface level electric fields at high-latitude locations. This produces a distinct phasing signature with the GEC potential that is shown to depend on the observation location around the globe. Lastly, the <span class="hlt">model</span> output for Vostok and Concordia, two high-latitude locations, is shown to agree with the observational data obtained at these sites over the same time period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A53J3330W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A53J3330W"><span><span class="hlt">Atmospheric</span> River <span class="hlt">Model</span> Simulation Diagnostics and Performance Metrics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Waliser, D. E.; Guan, B.; Kim, J.; Leung, L. R.; Ralph, F. M.</p> <p>2014-12-01</p> <p><span class="hlt">Atmospheric</span> Rivers (ARs) are narrow, elongated, synoptic jets of water vapor. These systems account for over 90% of the poleward transport of water vapor in mid-latitudes and thus are a key mechanism in help establish the water and energy cycles of the planet. Many of the intense wintertime hydrological (flood and drought-ending precipitation) events in the US western states (as well as in other continents) occur in conjunction with land-falling AR events. Despite the important role of the ARs in our climate and weather systems, there have been few broad characterizations of <span class="hlt">model</span> performance of ARs for global weather and climate <span class="hlt">models</span> (GCMs), in terms of their role in global climate or impacts associated with extreme weather. Part of the challenge has been the lack of a comprehensive set of observation-based <span class="hlt">model</span> simulation diagnostics and performance metrics. Based on the objectives and support from three activities: 1) the CalWater 2 AR project, 2) the Year of Tropical Convection (YOTC) and GEWEX <span class="hlt">Atmospheric</span> System Study (GASS) multi-<span class="hlt">model</span> experiment on Vertical Structure and Physical Processes of Weather & Climate, and 3) a new NASA effort examining the value added by dynamic regional climate <span class="hlt">model</span> (RCM) downscaling, we are working to develop a comprehensive set of AR simulation diagnostics and <span class="hlt">model</span> performance metrics for RCMs and GCMs. Application of these diagnostics and metrics will afford: 1) a baseline characterization of <span class="hlt">model</span> representations of synoptic features, impacts, and multi-scale interactions, 2) an ability to guide <span class="hlt">model</span> development and assess proposed improvements, 3) quantify the evolution in forecast skill, as well as 4) estimate predictability of AR characteristics and impacts. The purpose of this presentation is to initiate a more formal dialogue of this activity with the <span class="hlt">community</span>, present a preliminary set of diagnostics/metrics and illustrate their utility through application to the 27 GCMs that contributed simulations to the YOTC</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1214604-aeras-next-generation-global-atmosphere-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1214604-aeras-next-generation-global-atmosphere-model"><span>Aeras: A next generation global <span class="hlt">atmosphere</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Spotz, William F.; Smith, Thomas M.; Demeshko, Irina P.; ...</p> <p>2015-06-01</p> <p>Sandia National Laboratories is developing a new global <span class="hlt">atmosphere</span> <span class="hlt">model</span> named Aeras that is performance portable and supports the quantification of uncertainties. These next-generation capabilities are enabled by building Aeras on top of Albany, a code base that supports the rapid development of scientific application codes while leveraging Sandia's foundational mathematics and computer science packages in Trilinos and Dakota. Embedded uncertainty quantification (UQ) is an original design capability of Albany, and performance portability is a recent upgrade. Other required features, such as shell-type elements, spectral elements, efficient explicit and semi-implicit time-stepping, transient sensitivity analysis, and concurrent ensembles, were not componentsmore » of Albany as the project began, and have been (or are being) added by the Aeras team. We present early UQ and performance portability results for the shallow water equations.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1214604','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1214604"><span>Aeras: A next generation global <span class="hlt">atmosphere</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Spotz, William F.; Smith, Thomas M.; Demeshko, Irina P.; Fike, Jeffrey A.</p> <p>2015-06-01</p> <p>Sandia National Laboratories is developing a new global <span class="hlt">atmosphere</span> <span class="hlt">model</span> named Aeras that is performance portable and supports the quantification of uncertainties. These next-generation capabilities are enabled by building Aeras on top of Albany, a code base that supports the rapid development of scientific application codes while leveraging Sandia's foundational mathematics and computer science packages in Trilinos and Dakota. Embedded uncertainty quantification (UQ) is an original design capability of Albany, and performance portability is a recent upgrade. Other required features, such as shell-type elements, spectral elements, efficient explicit and semi-implicit time-stepping, transient sensitivity analysis, and concurrent ensembles, were not components of Albany as the project began, and have been (or are being) added by the Aeras team. We present early UQ and performance portability results for the shallow water equations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730059655&hterms=greenhouse+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dgreenhouse%2Beffect','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730059655&hterms=greenhouse+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dgreenhouse%2Beffect"><span>Greenhouse <span class="hlt">models</span> of the <span class="hlt">atmosphere</span> of Titan.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pollack, J. B.</p> <p>1973-01-01</p> <p>The greenhouse effect is calculated for a series of Titanian <span class="hlt">atmosphere</span> <span class="hlt">models</span> with different proportions of methane, hydrogen, helium, and ammonia. A computer program is used in temperature-structure calculations based on radiative-convective thermal transfer considerations. A brightness temperature spectrum is derived for Titan and is compared with available observational data. It is concluded that the greenhouse effect on Titan is generated by pressure-induced transitions of methane and hydrogen. The helium-to-hydrogen ratio is found to have a maximum of about 1.5. The surface pressure is estimated to be at least 0.4 atm, with a daytime temperature of about 155 K at the surface. The presence of methane clouds in the upper troposphere is indicated. The clouds have a significant optical depth in the visible, but not in the thermal, infrared.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27019423','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27019423"><span><span class="hlt">Modelling</span> Ebola within a <span class="hlt">community</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Leander, R N; Goff, W S; Murphy, C W; Pulido, S A</p> <p>2016-08-01</p> <p>The 2014 Ebola epidemic was the largest on record. It evidenced the need for improved <span class="hlt">models</span> of the spread of Ebola. In this research we focus on <span class="hlt">modelling</span> Ebola within a small village or <span class="hlt">community</span>. Specifically, we investigate the potential of basic Susceptible-Exposed-Infectious-Recovered (SEIR) <span class="hlt">models</span> to describe the initial Ebola outbreak, which occurred in Meliandou, Guinea. Data from the World Health Organization is used to compare the accuracy of various <span class="hlt">models</span> in order to select the most accurate <span class="hlt">models</span> of transmission and disease-induced responses. Our results suggest that (i) density-dependent transmission and mortality-induced behavioural changes shaped the course of the Ebola epidemic in Meliandou, while (ii) frequency-dependent transmission, disease-induced emigration, and infection-induced behavioural changes are not consistent with the data from this epidemic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170005366','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170005366"><span>Venus Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Status and Planned Updates</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justh, H. L.; Dwyer Cianciolo, A. M.</p> <p>2017-01-01</p> <p>The Venus Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (Venus-GRAM) was originally developed in 2004 under funding from NASA's In Space Propulsion (ISP) Aerocapture Project to support mission studies at the planet. Many proposals, including NASA New Frontiers and Discovery, as well as other studies have used Venus-GRAM to design missions and assess system robustness. After Venus-GRAM's release in 2005, several missions to Venus have generated a wealth of additional <span class="hlt">atmospheric</span> data, yet few <span class="hlt">model</span> updates have been made to Venus-GRAM. This paper serves to address three areas: (1) to present the current status of Venus-GRAM, (2) to identify new sources of data and other upgrades that need to be incorporated to maintain Venus-GRAM credibility and (3) to identify additional Venus-GRAM options and features that could be included to increase its capability. This effort will de-pend on understanding the needs of the user <span class="hlt">community</span>, obtaining new <span class="hlt">modeling</span> data and establishing a dedicated funding source to support continual up-grades. This paper is intended to initiate discussion that can result in an upgraded and validated Venus-GRAM being available to future studies and NASA proposals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ascl.soft12012L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ascl.soft12012L"><span>Meso-NH: Non-hydrostatic mesoscale <span class="hlt">atmospheric</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Laboratoire d'Aérologie; Centre National de Recherches Météorologiques</p> <p>2016-12-01</p> <p>Meso-NH is the non-hydrostatic mesoscale <span class="hlt">atmospheric</span> <span class="hlt">model</span> of the French research <span class="hlt">community</span> jointly developed by the Laboratoire d'Aérologie (UMR 5560 UPS/CNRS) and by CNRM (UMR 3589 CNRS/Météo-France). Meso-NH incorporates a non-hydrostatic system of equations for dealing with scales ranging from large (synoptic) to small (large eddy) scales while calculating budgets and has a complete set of physical parameterizations for the representation of clouds and precipitation. It is coupled to the surface <span class="hlt">model</span> SURFEX for representation of surface <span class="hlt">atmosphere</span> interactions by considering different surface types (vegetation, city, ocean, lake) and allows a multi-scale approach through a grid-nesting technique. Meso-NH is versatile, vectorized, parallelized, and operates in 1D, 2D or 3D; it is coupled with a chemistry module (including gas-phase, aerosol, and aqua-phase components) and a lightning module, and has observation operators that compare <span class="hlt">model</span> output directly with satellite observations, radar, lidar and GPS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=242243&keyword=apps&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=242243&keyword=apps&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Sensors and Apps for <span class="hlt">Community</span>-Based <span class="hlt">Atmospheric</span> Monitoring</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Recent advances in both sensors and wireless communication provide opportunities for improved exposure assessment and increasing <span class="hlt">community</span> involvement in reducing levels of human exposure to airborne contaminants. These new technologies can enhance data collection to answer scien...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=242243&keyword=magazine&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78814604&CFTOKEN=32062958','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=242243&keyword=magazine&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78814604&CFTOKEN=32062958"><span>Sensors and Apps for <span class="hlt">Community</span>-Based <span class="hlt">Atmospheric</span> Monitoring</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Recent advances in both sensors and wireless communication provide opportunities for improved exposure assessment and increasing <span class="hlt">community</span> involvement in reducing levels of human exposure to airborne contaminants. These new technologies can enhance data collection to answer scien...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMED31D3454S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMED31D3454S"><span>The National Science Foundation's Coupling, Energetics and Dynamics of <span class="hlt">Atmospheric</span> Regions (CEDAR) Student <span class="hlt">Community</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sox, L.; Duly, T.; Emery, B.</p> <p>2014-12-01</p> <p>The National Science Foundation sponsors Coupling, Energetics, and Dynamics of <span class="hlt">Atmospheric</span> Regions (CEDAR) Workshops, which have been held every summer, for the past 29 years. CEDAR Workshops are on the order of a week long and at various locations with the goal of being close to university campuses where CEDAR type scientific research is done. Although there is no formal student group within the CEDAR <span class="hlt">community</span>, the workshops are very student-focused. Roughly half the Workshop participants are students. There are two Student Representatives on the CEDAR Science Steering Committee (CSSC), the group of scientists who organize the CEDAR Workshops. Each Student Representative is nominated by his or her peers, chosen by the CSSC and then serves a two year term. Each year, one of the Student Representatives is responsible for organizing and moderating a day-long session targeted for students, made up of tutorial talks, which aim to prepare both undergraduate and graduate students for the topics that will be discussed in the main CEDAR Workshop. The theme of this session changes every year. Past themes have included: upper <span class="hlt">atmospheric</span> instrumentation, numerical <span class="hlt">modeling</span>, <span class="hlt">atmospheric</span> waves and tides, magnetosphere-ionosphere coupling, equatorial aeronomy and many others. Frequently, the Student Workshop has ended with a panel of post-docs, researchers and professors who discuss pressing questions from the students about the next steps they will take in their careers. As the present and past CSSC Student Representatives, we will recount a brief history of the CEDAR Workshops, our experiences serving on the CSSC and organizing the Student Workshop, a summary of the feedback we collected about the Student Workshops and what it's like to be student in the CEDAR <span class="hlt">community</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950054943&hterms=constrained+factor+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconstrained%2Bfactor%2Bmodel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950054943&hterms=constrained+factor+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconstrained%2Bfactor%2Bmodel"><span>A photochemical <span class="hlt">model</span> of the martian <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nair, Hari; Allen, Mark; Anbar, Ariel D.; Yung, Yuk L; Clancy, R. Todd</p> <p>1994-01-01</p> <p>The factors governing the amounts of CO, O2, and O3 in the martian atmposphere are investigated using a minimally constrained, one-dimensional photochemical <span class="hlt">model</span>. We find that the incorporation of temperature-dependent CO2 absorption cross sections leads to an enhancement in the water photolysis rate, increasing the abundance of OH radicals to the point where the <span class="hlt">model</span> CO abundance is smaller that observed. Good agreement between <span class="hlt">models</span> and observations of CO, O2, O3, and the escape flux of atomic hydrogen can be achieved, using only gas-phase chemistry, by varying the recommended rate constraints for the reaction CO + OH and OH + HO2 within their specified uncertainties. The oxygen escape flux plays a key role in the oxygen budget on Mars; as inferred from the observed atomic hydrogen escape, it is much larger than recent calculations of the exospheric escape rate for oxygen. Weathering of the surface may account for the imbalance. We also consider the possiblity that HO(x) radicals may be catalytically destroyed on dust grains suspended in the <span class="hlt">atmosphere</span>. Good agreement with the observed CO mixing ratio can be achieved via this mechanism, but the resulting ozone column is much higher than the observed quantity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APS..MARQ30008M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APS..MARQ30008M"><span>Multiscale <span class="hlt">Atmospheric</span> Physics <span class="hlt">Modeled</span> by Cumulant Expansions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marston, Brad; Chini, Greg</p> <p>2014-03-01</p> <p>We investigate a systematic and physically based approach to <span class="hlt">modeling</span> subgrid physics statistically with the use of an expansion in equal-time cumulants. To accomplish this we replace the zonal average employed in previous work with a low-pass filter that separates small and large scales in the zonal direction. The statistics are non-local, inhomogeneous, and anisotropic; the sole approximation is the neglect of 3-point and higher correlation functions. The closure respects the conservation of energy, enstrophy, and angular momentum. An advantage of the formulation is that correlations between large and small scale processes are treated explicitly without the introduction of phenomenological parameterizations. The approach is tested against full numerical simulation of idealized 1- and 2-layer <span class="hlt">models</span> of the <span class="hlt">atmospheric</span> general circulation and shown to yield accurate low-order statistics. (The computer <span class="hlt">model</span> used to perform these tests runs on OS X and is publicly available.) We identify important multiscale interactions and discuss the computational cost of the new scheme. Supported in part by NSF DMR-1306806 and CCF-1048701.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1212767-fungi-future-interannual-variation-effects-atmospheric-change-arbuscular-mycorrhizal-fungal-communities','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1212767-fungi-future-interannual-variation-effects-atmospheric-change-arbuscular-mycorrhizal-fungal-communities"><span>Fungi in the future: Interannual variation and effects of <span class="hlt">atmospheric</span> change on arbuscular mycorrhizal fungal <span class="hlt">communities</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Cotton, T. E. Anne; Fitter, Alastair H.; Miller, R. Michael; ...</p> <p>2015-01-05</p> <p>Understanding the natural dynamics of arbuscular mycorrhizal (AM) fungi and their response to global environmental change is essential for the prediction of future plant growth and ecosystem functions. We investigated the long-term temporal dynamics and effect of elevated <span class="hlt">atmospheric</span> carbon dioxide (CO2) and ozone (O3) concentrations on AM fungal <span class="hlt">communities</span>. Molecular methods were used to characterize the AM fungal <span class="hlt">communities</span> of soybean (Glycine max) grown under elevated and ambient <span class="hlt">atmospheric</span> concentrations of both CO2 and O3 within a free air concentration enrichment experiment in three growing seasons over 5 yr. Elevated CO2 altered the <span class="hlt">community</span> composition of AM fungi, increasingmore » the ratio of Glomeraceae to Gigasporaceae. By contrast, no effect of elevated O3 on AM fungal <span class="hlt">communities</span> was detected. However, the greatest compositional differences detected were between years, suggesting that, at least in the short term, large-scale interannual temporal dynamics are stronger mediators than <span class="hlt">atmospheric</span> CO2 concentrations of AM fungal <span class="hlt">communities</span>. We conclude that, although <span class="hlt">atmospheric</span> change may significantly alter AM fungal <span class="hlt">communities</span>, this effect may be masked by the influences of natural changes and successional patterns through time. We suggest that changes in carbon availability are important determinants of the <span class="hlt">community</span> dynamics of AM fungi.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1212767','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1212767"><span>Fungi in the future: Interannual variation and effects of <span class="hlt">atmospheric</span> change on arbuscular mycorrhizal fungal <span class="hlt">communities</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cotton, T. E. Anne; Fitter, Alastair H.; Miller, R. Michael; Dumbrell, Alex J.; Helgason, Thorunn</p> <p>2015-01-05</p> <p>Understanding the natural dynamics of arbuscular mycorrhizal (AM) fungi and their response to global environmental change is essential for the prediction of future plant growth and ecosystem functions. We investigated the long-term temporal dynamics and effect of elevated <span class="hlt">atmospheric</span> carbon dioxide (CO<sub>2</sub>) and ozone (O<sub>3</sub>) concentrations on AM fungal <span class="hlt">communities</span>. Molecular methods were used to characterize the AM fungal <span class="hlt">communities</span> of soybean (<i>Glycine max</i>) grown under elevated and ambient <span class="hlt">atmospheric</span> concentrations of both CO<sub>2</sub> and O<sub>3</sub> within a free air concentration enrichment experiment in three growing seasons over 5 yr. Elevated CO<sub>2</sub> altered the <span class="hlt">community</span> composition of AM fungi, increasing the ratio of Glomeraceae to Gigasporaceae. By contrast, no effect of elevated O<sub>3</sub> on AM fungal <span class="hlt">communities</span> was detected. However, the greatest compositional differences detected were between years, suggesting that, at least in the short term, large-scale interannual temporal dynamics are stronger mediators than <span class="hlt">atmospheric</span> CO<sub>2</sub> concentrations of AM fungal <span class="hlt">communities</span>. We conclude that, although <span class="hlt">atmospheric</span> change may significantly alter AM fungal <span class="hlt">communities</span>, this effect may be masked by the influences of natural changes and successional patterns through time. We suggest that changes in carbon availability are important determinants of the <span class="hlt">community</span> dynamics of AM fungi.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040068067&hterms=outer+planets&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Douter%2Bplanets','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040068067&hterms=outer+planets&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Douter%2Bplanets"><span>Connecting <span class="hlt">Atmospheric</span> Science and <span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Aerocaptured Missions to Titan and the Outer Planets</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Duvall, Aleta; Keller, Vernon W.</p> <p>2003-01-01</p> <p>Many <span class="hlt">atmospheric</span> measurement systems, such as the sounding instruments on Voyager, gather <span class="hlt">atmospheric</span> information in the form of temperature versus pressure level. In these terms, there is considerable consistency among the mean <span class="hlt">atmospheric</span> profiles of the outer planets Jupiter through Neptune, including Titan. On a given planet or on Titan, the range of variability of temperature versus pressure level due to seasonal, latitudinal, and diurnal variations is also not large. However, many engineering needs for <span class="hlt">atmospheric</span> <span class="hlt">models</span> relate not to temperature versus pressure level but <span class="hlt">atmospheric</span> density versus geometric altitude. This need is especially true for design and analysis of aerocapture systems. Aerocapture drag force available for aerocapture is directly proportional to <span class="hlt">atmospheric</span> density. Available aerocapture "corridor width" (allowable range of <span class="hlt">atmospheric</span> entry angle) also depends on height rate of change of <span class="hlt">atmospheric</span> density, as characterized by density scale height. Characteristics of hydrostatics and the gas law equation mean that relatively small systematic differences in temperature-versus-pressure profiles can integrate at high altitudes to very large differences in density-versus-altitude profiles. Thus a given periapsis density required to accomplish successful aerocapture can occur at substantially different altitudes (approx. 150 - 300 km) on the various outer planets, and significantly different density scale heights (approx. 20 - 50 km) can occur at these periapsis altitudes. This paper will illustrate these effects and discuss implications for improvements in <span class="hlt">atmospheric</span> measurements to yield significant impact on design of aerocapture systems for future missions to Titan and the outer planets. Relatively small- scale <span class="hlt">atmospheric</span> perturbations, such as gravity waves, tides, and other <span class="hlt">atmospheric</span> variations can also have significant effect on design details for aerocapture guidance and control systems. This paper will also discuss benefits</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6348641','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6348641"><span>Middle <span class="hlt">atmosphere</span> density and <span class="hlt">models</span>. Technical report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Champion, K.</p> <p>1987-04-09</p> <p>The 80 to 130 km altitude region is our old ionosphere - the region of the <span class="hlt">atmosphere</span> that no one seems to be interested in, and yet the critical region for shuttle entry and <span class="hlt">atmospheric</span> braking. Comparison between the Air Force reference <span class="hlt">atmosphere</span> and Shuttle IMU data shows large fluctuations at high latitudes. New data sources are available now, such as the Arecibo and Millstone Hill ionospheric scatter radars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950002041&hterms=NASA+Climate+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DNASA%2BClimate%2Bresearch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950002041&hterms=NASA+Climate+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DNASA%2BClimate%2Bresearch"><span>Numerical analysis and <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> phenomena</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stone, Peter H.</p> <p>1994-01-01</p> <p>For the past 22 years Grant NGR 22-009-727 has been supporting research in the Center for Meteorology and Physical Oceanography (and its predecessors) in a wide variety of diagnostic and <span class="hlt">modeling</span> studies of <span class="hlt">atmospheric</span> and ocean phenomena. Professor Jule Charney was the initial Principal Investigator. Professor Peter Stone joined him as co-Principal Investigator in 1975 and became the sole Principal Investigator in 1981. During its lifetime the Grant has supported in whole or in part 11 Master's theses, 14 Ph.D. theses, and 45 papers published in refereed scientific journals. All of these theses and papers (with bibliographic references) are listed below. All but one of the theses were used to fulfill the requirements for MIT (Massachusetts Institute of Technology) degrees and are available from the MIT libraries. The one exception is F. Chen's Ph.D. thesis which was for a Harvard degree and is available from the Harvard libraries. In addition to the work described in the citations listed below, the Grant has supported Research Assistant Amy Solomon during the past two years to carry out a study of how baroclinic adjustment is affected by vertical resolution, vertical temperature structure, and dissipation. Ms. Solomon plans to use this project for her Ph.D. thesis. Support for this project will continue under NASA Grant NAG 5-2490, 'The Factors Controlling Poleward Heat Transport in Climate <span class="hlt">Models</span>.'</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A23A0185F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A23A0185F"><span>Evaluation of <span class="hlt">atmospheric</span> chemical <span class="hlt">models</span> using aircraft data (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Freeman, S.; Grossberg, N.; Pierce, R.; Lee, P.; Ngan, F.; Yates, E. L.; Iraci, L. T.; Lefer, B. L.</p> <p>2013-12-01</p> <p>Air quality prediction is an important and growing field, as the adverse health effects of ozone (O3) are becoming more important to the general public. Two <span class="hlt">atmospheric</span> chemical <span class="hlt">models</span>, the Realtime Air Quality <span class="hlt">Modeling</span> System (RAQMS) and the <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">modeling</span> system (CMAQ) are evaluated during NASA's Student Airborne Research Project (SARP) and the NASA Alpha Jet <span class="hlt">Atmospheric</span> eXperiment (AJAX) flights. CO, O3, and NOx data simulated by the <span class="hlt">models</span> are interpolated using an inverse distance weighting in space and a linear interpolation in time to both the SARP and AJAX flight tracks and compared to the CO, O3, and NOx observations at those points. Results for the seven flights included show moderate error in O3 during the flights, with RAQMS having a high O3 bias (+15.7 ppbv average) above 6 km and a low O3 bias (-17.5 ppbv average) below 4km. CMAQ was found to have a low O3 bias (-13.0 ppbv average) everywhere. Additionally, little bias (-5.36% RAQMS, -11.8% CMAQ) in the CO data was observed with the exception of a wildfire smoke plume that was flown through on one SARP flight, as CMAQ lacks any wildfire sources and RAQMS resolution is too coarse to resolve narrow plumes. This indicates improvement in emissions inventories compared to previous studies. CMAQ additionally incorrectly predicted a NOx plume due to incorrectly vertically advecting it from the surface, which caused NOx titration to occur, limiting the production of ozone. This study shows that these <span class="hlt">models</span> perform reasonably well in most conditions; however more work must be done to assimilate wildfires, improve emissions inventories, and improve meteorological forecasts for the <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000030684','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000030684"><span><span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for Novae in Outburst: Summary of Research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hauschildt, Peter H.</p> <p>1999-01-01</p> <p>This paper presents a final report and summary of research on <span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for Novae in Outburst. Some of the topics include: 1) Detailed NLTE (non-local thermodynamic equilibrium) <span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for Novae during Outburst: II. <span class="hlt">Modeling</span> optical and ultraviolet observations of Nova LMC 1988 #1; 2) A Non-LTE Line-Blanketed Stellar <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> of the Early B Giant epsilon CMa; 3) Spectroscopy of Low Metallicity Stellar <span class="hlt">atmospheres</span>; 4) Infrared Colors at the Stellar/Substellar Boundary; 5) On the abundance of Lithium in T CrB; 6) Numerical Solution of the Expanding Stellar <span class="hlt">Atmosphere</span> Problem; and 7) The NextGen <span class="hlt">Model</span> <span class="hlt">Atmosphere</span> grid for 3000 less than or equal to T (sub eff) less than or equal to 10000K.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170000753','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170000753"><span>Chemistry Simulations using the MERRA-2 Reanalysis with the GMI CTM and Replay in Support of the <span class="hlt">Atmospheric</span> Composition <span class="hlt">Community</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Oman, Luke D.; Strahan, Susan E.</p> <p>2017-01-01</p> <p>Simulations using reanalysis meteorological fields have long been used to understand the causes of <span class="hlt">atmospheric</span> composition change in the recent past. Using the new MERRA-2 reanalysis, we are conducting chemistry simulations to create products covering 1980-2016 for the <span class="hlt">atmospheric</span> composition <span class="hlt">community</span>. These simulations use the Global <span class="hlt">Modeling</span> Initiative (GMI) chemical mechanism in two different <span class="hlt">models</span>: the GMI Chemical Transport <span class="hlt">Model</span> (CTM) and the GEOS-5 <span class="hlt">model</span> in Replay mode. Replay mode means an integration of the GEOS-5 general circulation <span class="hlt">model</span> that is incrementally adjusted each time step toward the MERRA-2 reanalysis. The GMI CTM is a 1 deg x 1.25 deg simulation and the MERRA-2 GMI Replay simulation uses the native MERRA-2 grid of approximately 1/2 deg horizontal resolution on the cubed sphere. A specialized set of transport diagnostics is included in both runs to better understand trace gas transport and its variability in the recent past.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75840&keyword=processor+AND+data&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78772424&CFTOKEN=39555396','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=75840&keyword=processor+AND+data&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78772424&CFTOKEN=39555396"><span>DESCRIPTION OF <span class="hlt">ATMOSPHERIC</span> TRANSPORT PROCESSES IN EULERIAN AIR QUALITY <span class="hlt">MODELS</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Key differences among many types of air quality <span class="hlt">models</span> are the way <span class="hlt">atmospheric</span> advection and turbulent diffusion processes are treated. Gaussian <span class="hlt">models</span> use analytical solutions of the advection-diffusion equations. Lagrangian <span class="hlt">models</span> use a hypothetical air parcel concept effecti...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870003657&hterms=ASD&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DASD','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870003657&hterms=ASD&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DASD"><span><span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> And Sensor Simulation (AMASS) study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parker, K. G.</p> <p>1985-01-01</p> <p>A 4800 band synchronous communications link was established between the Perkin-Elmer (P-E) 3250 <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> and Sensor Simulation (AMASS) system and the Cyber 205 located at the Goddard Space Flight Center. An extension study of off-the-shelf array processors offering standard interface to the Perkin-Elmer was conducted to determine which would meet computational requirements of the division. A Floating Point Systems AP-120B was borrowed from another Marshall Space Flight Center laboratory for evaluation. It was determined that available array processors did not offer significantly more capabilities than the borrowed unit, although at least three other vendors indicated that standard Perkin-Elmer interfaces would be marketed in the future. Therefore, the recommendation was made to continue to utilize the 120B ad to keep monitoring the AP market. Hardware necessary to support requirements of the ASD as well as to enhance system performance was specified and procured. Filters were implemented on the Harris/McIDAS system including two-dimensional lowpass, gradient, Laplacian, and bicubic interpolation routines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1029045','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1029045"><span>The <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> Version 4</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gent, Peter R.; Danabasoglu, Gokhan; Donner, Leo J.; Holland, Marika M.; Hunke, Elizabeth C.; Jayne, Steve R.; Lawrence, David M.; Neale, Richard; Rasch, Philip J.; Vertenstein, Mariana; Worley, Patrick; Yang, Zong-Liang; Zhang, Minghua</p> <p>2011-10-01</p> <p>The fourth version of the <span class="hlt">Community</span> Climate System <span class="hlt">Model</span> (CCSM4) was recently completed and released to the climate <span class="hlt">community</span>. This paper describes developments to all the CCSM components, and documents fully coupled pre-industrial control runs compared to the previous version, CCSM3. Using the standard <span class="hlt">atmosphere</span> and land resolution of 1{sup o} results in the sea surface temperature biases in the major upwelling regions being comparable to the 1.4{sup o} resolution CCSM3. Two changes to the deep convection scheme in the <span class="hlt">atmosphere</span> component result in the CCSM4 producing El Nino/Southern Oscillation variability with a much more realistic frequency distribution than the CCSM3, although the amplitude is too large compared to observations. They also improve the representation of the Madden-Julian Oscillation, and the frequency distribution of tropical precipitation. A new overflow parameterization in the ocean component leads to an improved simulation of the deep ocean density structure, especially in the North Atlantic. Changes to the CCSM4 land component lead to a much improved annual cycle of water storage, especially in the tropics. The CCSM4 sea ice component uses much more realistic albedos than the CCSM3, and the Arctic sea ice concentration is improved in the CCSM4. An ensemble of 20th century simulations runs produce an excellent match to the observed September Arctic sea ice extent from 1979 to 2005. The CCSM4 ensemble mean increase in globally-averaged surface temperature between 1850 and 2005 is larger than the observed increase by about 0.4 C. This is consistent with the fact that the CCSM4 does not include a representation of the indirect effects of aerosols, although other factors may come into play. The CCSM4 still has significant biases, such as the mean precipitation distribution in the tropical Pacific Ocean, too much low cloud in the Arctic, and the latitudinal distributions of short-wave and long-wave cloud forcings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990021046&hterms=Application+Thermodynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DApplication%2BThermodynamic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990021046&hterms=Application+Thermodynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DApplication%2BThermodynamic"><span>Application of the Regional <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> System to the Martian <span class="hlt">Atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rafkin, Scot C. R.</p> <p>1998-01-01</p> <p>The core dynamics of the Regional <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> System (RAMS), a widely used and powerful mesoscale Earth <span class="hlt">model</span>, is adapted to the Martian <span class="hlt">Atmosphere</span> and applied in the study of aeolian surface features. In particular, research efforts focused on the substitution of Martian planetary and <span class="hlt">atmospheric</span> properties such as rotation rate, and thermodynamic constants in place of hard-wired Earth properties. Application of the <span class="hlt">model</span> was restricted to three-dimensional flow impinging upon impact craters, and the search for plausible wind patterns that could produce the so-called light and dark streaks downwind of topographic barriers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70022639','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70022639"><span>A <span class="hlt">Community</span> Hydrometeorology Laboratory for Fostering Collaborative Research by the <span class="hlt">Atmospheric</span> and Hydrologic Sciences</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Warner, T.T.; Yates, D.N.; Leavesley, G.H.</p> <p>2000-01-01</p> <p>A new <span class="hlt">community</span> laboratory for fostering collaborative research between the <span class="hlt">atmospheric</span> and hydrologie sciences <span class="hlt">communities</span> is described. This facility, located at the National Center for <span class="hlt">Atmospheric</span> Research (NCAR) in Boulder, Colorado, allows scientists from both <span class="hlt">communities</span> to more easily focus resources and attention on interdisciplinary problems in <span class="hlt">atmospheric</span>, hydrologic, and other related sciences. Researchers can remotely access the computing tools to use them or to download them to their own facility, or they can visit NCAR and use the laboratory with other scientists in joint research projects. An application of this facility is described, where scientists from NCAR, the University of Colorado, and the United States Geological Survey used quantitative precipitation estimates from weather radar to simulate a flash flood in the Buffalo Creek watershed in the mountainous Front Range near Denver, Colorado.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830004412','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830004412"><span><span class="hlt">Atmospheric</span> Backscatter <span class="hlt">Model</span> Development for CO Sub 2 Wavelengths</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Deepak, A.; Kent, G.; Yue, G. K.</p> <p>1982-01-01</p> <p>The results of investigations into the problems of <span class="hlt">modeling</span> <span class="hlt">atmospheric</span> backscatter from aerosols, in the lowest 20 km of the <span class="hlt">atmosphere</span>, at CO2 wavelengths are presented, along with a summary of the relevant aerosol characteristics and their variability, and a discussion of the measurement techniques and errors involved. The different methods of calculating the aerosol backscattering function, both from measured aerosol characteristics and from optical measurements made at other wavelengths, are discussed in detail, and limits are placed on the accuracy of these methods. The effects of changing <span class="hlt">atmospheric</span> humidity and temperature on the backscatter are analyzed and related to the actual <span class="hlt">atmosphere</span>. Finally, the results of <span class="hlt">modeling</span> CO2 backscatter in the <span class="hlt">atmosphere</span> are presented and the variation with height and geographic location discussed, and limits placed on the magnitude of the backscattering function. Conclusions regarding <span class="hlt">modeling</span> techniques and <span class="hlt">modeled</span> <span class="hlt">atmospheric</span> backscatter values are presented in tabular form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9990G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9990G"><span>Radiative and dynamical <span class="hlt">modeling</span> of Jupiter's <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guerlet, Sandrine; Spiga, Aymeric</p> <p>2016-04-01</p> <p>Jupiter's <span class="hlt">atmosphere</span> harbours a rich meteorology, with alternate westward and eastward zonal jets, waves signatures and long-living storms. Recent ground-based and spacecraft measurements have also revealed a rich stratospheric dynamics, with the observation of thermal signatures of planetary waves, puzzling meridional distribution of hydrocarbons at odds with predictions of photochemical <span class="hlt">models</span>, and a periodic equatorial oscillation analogous to the Earth's quasi-biennal oscillation and Saturn's equatorial oscillation. These recent observations, along with the many unanswered questions (What drives and maintain the equatorial oscillations? How important is the seasonal forcing compared to the influence of internal heat? What is the large-scale stratospheric circulation of these giant planets?) motivated us to develop a complete 3D General Circulation <span class="hlt">Model</span> (GCM) of Saturn and Jupiter. We aim at exploring the large-scale circulation, seasonal variability, and wave activity from the troposphere to the stratosphere of these giant planets. We will briefly present how we adapted our existing Saturn GCM to Jupiter. One of the main change is the addition of a stratospheric haze layer made of fractal aggregates in the auroral regions (poleward of 45S and 30N). This haze layer has a significant radiative impact by modifying the temperature up to +/- 15K in the middle stratosphere. We will then describe the results of radiative-convective simulations and how they compare to recent Cassini and ground-based temperature measurements. These simulations reproduce surprisingly well some of the observed thermal vertical and meridional gradients, but several important mismatches at low and high latitudes suggest that dynamics also plays an important role in shaping the temperature field. Finally, we will present full GCM simulations and discuss the main resulting features (waves and instabilities). We will also and discuss the impact of the choice of spatial resolution and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ACP....17.5271T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ACP....17.5271T"><span>Multi-<span class="hlt">model</span> study of mercury dispersion in the <span class="hlt">atmosphere</span>: <span class="hlt">atmospheric</span> processes and <span class="hlt">model</span> evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Travnikov, Oleg; Angot, Hélène; Artaxo, Paulo; Bencardino, Mariantonia; Bieser, Johannes; D'Amore, Francesco; Dastoor, Ashu; De Simone, Francesco; Diéguez, María del Carmen; Dommergue, Aurélien; Ebinghaus, Ralf; Feng, Xin Bin; Gencarelli, Christian N.; Hedgecock, Ian M.; Magand, Olivier; Martin, Lynwill; Matthias, Volker; Mashyanov, Nikolay; Pirrone, Nicola; Ramachandran, Ramesh; Read, Katie Alana; Ryjkov, Andrei; Selin, Noelle E.; Sena, Fabrizio; Song, Shaojie; Sprovieri, Francesca; Wip, Dennis; Wängberg, Ingvar; Yang, Xin</p> <p>2017-04-01</p> <p>Current understanding of mercury (Hg) behavior in the <span class="hlt">atmosphere</span> contains significant gaps. Some key characteristics of Hg processes, including anthropogenic and geogenic emissions, <span class="hlt">atmospheric</span> chemistry, and air-surface exchange, are still poorly known. This study provides a complex analysis of processes governing Hg fate in the <span class="hlt">atmosphere</span> involving both measured data from ground-based sites and simulation results from chemical transport <span class="hlt">models</span>. A variety of long-term measurements of gaseous elemental Hg (GEM) and reactive Hg (RM) concentration as well as Hg wet deposition flux have been compiled from different global and regional monitoring networks. Four contemporary global-scale transport <span class="hlt">models</span> for Hg were used, both in their state-of-the-art configurations and for a number of numerical experiments to evaluate particular processes. Results of the <span class="hlt">model</span> simulations were evaluated against measurements. As follows from the analysis, the interhemispheric GEM gradient is largely formed by the prevailing spatial distribution of anthropogenic emissions in the Northern Hemisphere. The contributions of natural and secondary emissions enhance the south-to-north gradient, but their effect is less significant. <span class="hlt">Atmospheric</span> chemistry has a limited effect on the spatial distribution and temporal variation of GEM concentration in surface air. In contrast, RM air concentration and wet deposition are largely defined by oxidation chemistry. The Br oxidation mechanism can reproduce successfully the observed seasonal variation of the RM / GEM ratio in the near-surface layer, but it predicts a wet deposition maximum in spring instead of in summer as observed at monitoring sites in North America and Europe. <span class="hlt">Model</span> runs with OH chemistry correctly simulate both the periods of maximum and minimum values and the amplitude of observed seasonal variation but shift the maximum RM / GEM ratios from spring to summer. O3 chemistry does not predict significant seasonal variation of Hg</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=development&id=EJ1132410','ERIC'); return false;" href="https://eric.ed.gov/?q=development&id=EJ1132410"><span><span class="hlt">Models</span> of <span class="hlt">Community</span> Colleges in Mainland China</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Zhang, Yi</p> <p>2017-01-01</p> <p>This chapter provides an overview of <span class="hlt">community</span> colleges in mainland China, addressing briefly the recent history of <span class="hlt">community</span> college development, defining these institutions, detailing various <span class="hlt">models</span> with examples, and discussing challenges faced by these institutions and recommendations for future development.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28596763','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28596763"><span>Methanogenic <span class="hlt">Community</span> Was Stable in Two Contrasting Freshwater Marshes Exposed to Elevated <span class="hlt">Atmospheric</span> CO2.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Yongxin; Liu, Deyan; Yuan, Junji; Ye, Guiping; Ding, Weixin</p> <p>2017-01-01</p> <p>The effects of elevated <span class="hlt">atmospheric</span> CO2 concentration on soil microbial <span class="hlt">communities</span> have been previously recorded. However, limited information is available regarding the response of methanogenic <span class="hlt">communities</span> to elevated CO2 in freshwater marshes. Using high-throughput sequencing and real-time quantitative PCR, we compared the abundance and <span class="hlt">community</span> structure of methanogens in different compartments (bulk soil, rhizosphere soil, and roots) of Calamagrostis angustifolia and Carex lasiocarpa growing marshes under ambient (380 ppm) and elevated CO2 (700 ppm) <span class="hlt">atmospheres</span>. C. lasiocarpa rhizosphere was a hotspot for potential methane production, based on the 10-fold higher abundance of the mcrA genes per dry weight. The two marshes and their compartments were occupied by different methanogenic <span class="hlt">communities</span>. In the C. lasiocarpa marsh, archaeal family Methanobacteriaceae, Rice Cluster II, and Methanosaetaceae co-dominated in the bulk soil, while Methanobacteriaceae was the exclusively dominant methanogen in the rhizosphere soil and roots. Families Methanosarcinaceae and Methanocellaceae dominated in the bulk soil of C. angustifolia marsh. Conversely, Methanosarcinaceae and Methanocellaceae together with Methanobacteriaceae dominated in the rhizosphere soil and roots, respectively, in the C. angustifolia marsh. Elevated <span class="hlt">atmospheric</span> CO2 increased plant photosynthesis and belowground biomass of C. lasiocarpa and C. angustifolia marshes. However, it did not significantly change the abundance (based on mcrA qPCR), diversity, or <span class="hlt">community</span> structure (based on high-throughput sequencing) of methanogens in any of the compartments, irrespective of plant type. Our findings suggest that the population and species of the dominant methanogens had weak responses to elevated <span class="hlt">atmospheric</span> CO2. However, minor changes in specific methanogenic taxa occurred under elevated <span class="hlt">atmospheric</span> CO2. Despite minor changes, methanogenic <span class="hlt">communities</span> in different compartments of two contrasting freshwater</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5442310','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5442310"><span>Methanogenic <span class="hlt">Community</span> Was Stable in Two Contrasting Freshwater Marshes Exposed to Elevated <span class="hlt">Atmospheric</span> CO2</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lin, Yongxin; Liu, Deyan; Yuan, Junji; Ye, Guiping; Ding, Weixin</p> <p>2017-01-01</p> <p>The effects of elevated <span class="hlt">atmospheric</span> CO2 concentration on soil microbial <span class="hlt">communities</span> have been previously recorded. However, limited information is available regarding the response of methanogenic <span class="hlt">communities</span> to elevated CO2 in freshwater marshes. Using high-throughput sequencing and real-time quantitative PCR, we compared the abundance and <span class="hlt">community</span> structure of methanogens in different compartments (bulk soil, rhizosphere soil, and roots) of Calamagrostis angustifolia and Carex lasiocarpa growing marshes under ambient (380 ppm) and elevated CO2 (700 ppm) <span class="hlt">atmospheres</span>. C. lasiocarpa rhizosphere was a hotspot for potential methane production, based on the 10-fold higher abundance of the mcrA genes per dry weight. The two marshes and their compartments were occupied by different methanogenic <span class="hlt">communities</span>. In the C. lasiocarpa marsh, archaeal family Methanobacteriaceae, Rice Cluster II, and Methanosaetaceae co-dominated in the bulk soil, while Methanobacteriaceae was the exclusively dominant methanogen in the rhizosphere soil and roots. Families Methanosarcinaceae and Methanocellaceae dominated in the bulk soil of C. angustifolia marsh. Conversely, Methanosarcinaceae and Methanocellaceae together with Methanobacteriaceae dominated in the rhizosphere soil and roots, respectively, in the C. angustifolia marsh. Elevated <span class="hlt">atmospheric</span> CO2 increased plant photosynthesis and belowground biomass of C. lasiocarpa and C. angustifolia marshes. However, it did not significantly change the abundance (based on mcrA qPCR), diversity, or <span class="hlt">community</span> structure (based on high-throughput sequencing) of methanogens in any of the compartments, irrespective of plant type. Our findings suggest that the population and species of the dominant methanogens had weak responses to elevated <span class="hlt">atmospheric</span> CO2. However, minor changes in specific methanogenic taxa occurred under elevated <span class="hlt">atmospheric</span> CO2. Despite minor changes, methanogenic <span class="hlt">communities</span> in different compartments of two contrasting freshwater</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1004432','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1004432"><span>Midnight Temperature Maximum (MTM) in Whole <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (WAM) Simulations</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2016-04-14</p> <p>Midnight temperature maximum (MTM) in Whole <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (WAM) simulations R. A. Akmaev,1 F. Wu,2 T. J. Fuller-Rowell,2 and H. Wang2 Received 13...been unsuccessful. First long-term simulations with the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> (WAM) reveal the presence of a realistically prominent MTM and reproduce...involve nonlinear interactions between other tidal harmonics originating in the middle and lower <span class="hlt">atmosphere</span> . Our results thus suggest that the MTM is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19890010979','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19890010979"><span>A preliminary weather <span class="hlt">model</span> for optical communications through the <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shaik, K. S.</p> <p>1988-01-01</p> <p>A preliminary weather <span class="hlt">model</span> is presented for optical propagation through the <span class="hlt">atmosphere</span>. It can be used to compute the attenuation loss due to the <span class="hlt">atmosphere</span> for desired link availability statistics. The quantitative results that can be obtained from this <span class="hlt">model</span> provide good estimates for the <span class="hlt">atmospheric</span> link budget necessary for the design of an optical communication system. The result is extended to provide for the computation of joint attenuation probability for n sites with uncorrelated weather patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910169V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910169V"><span><span class="hlt">Modelling</span> of Titan's middle <span class="hlt">atmosphere</span> with the IPSL climate <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vatant d'Ollone, Jan; Lebonnois, Sébastien; Guerlet, Sandrine</p> <p>2017-04-01</p> <p>Titan's 3-dimensional Global Climate <span class="hlt">Model</span> developed at the Institute Pierre-Simon Laplace has already demonstrated its efficiency to reproduce and interpret many features of the Saturnian moon's climate (e.g. Lebonnois et al., 2012). However, it suffered from limits at the top of the <span class="hlt">model</span>, with temperatures far warmer than the observations and no stratopause simulated. To interpret Cassini's overall observations of seasonal effects in the middle <span class="hlt">atmosphere</span> (e.g. Vinatier et al., 2015), a satisfying <span class="hlt">modelling</span> of the temperature profile in this region was first required. Latest developments in the GCM now enable a correct <span class="hlt">modelling</span> of the temperature profile in the middle <span class="hlt">atmosphere</span>. In particular, a new, more flexible, radiative transfer scheme based on correlated-k method has been set up, using up-to-date spectroscopic data. Special emphasis is put on the too warm upper stratospheric temperatures in the former <span class="hlt">model</span> that were due to the absence of the infrared ν4 methane line (7.7 μm) in the radiative transfer. While it was usually neglected in the tropospheric radiative <span class="hlt">models</span>, this line has a strong cooling effect in Titan's stratospheric conditions and cannot be neglected. In this new version of the GCM, the microphysical <span class="hlt">model</span> is temporarily switched off and we use a mean profile for haze opacity (Lavvas et al., 2010). The circulation in the middle <span class="hlt">atmosphere</span> is significantly improved by this new radiative transfer. The new 3-D simulations also show an interesting feature in the <span class="hlt">modeled</span> vertical profile of the zonal wind as the minimum in low stratosphere is now closer to the observations. Works in progress such as the vertical extension and the computation of the radiative effect of the seasonal variations of trace components will also be presented. - Lavvas P. et al., 2010. Titan's vertical aerosol structure at the Huygens landing site: Constraints on particle size, density, charge, and refractive index. Icarus 210, 832-842. - Lebonnois S. et al., 2012</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ESSDD...8..603S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ESSDD...8..603S"><span>Gridded global surface ozone metrics for <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span> evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sofen, E. D.; Bowdalo, D.; Evans, M. J.; Apadula, F.; Bonasoni, P.; Cupeiro, M.; Ellul, R.; Galbally, I. E.; Girgzdiene, R.; Luppo, S.; Mimouni, M.; Nahas, A. C.; Saliba, M.; Tørseth, K.; Wmo Gaw, Epa Aqs, Epa Castnet, Capmon, Naps, Airbase, Emep, Eanet Ozone Datasets, All Other Contributors To</p> <p>2015-07-01</p> <p>The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and <span class="hlt">atmospheric</span> chemistry research. We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent dataset for the evaluation of chemical transport and chemistry-climate (Earth System) <span class="hlt">models</span> for projects such as the Chemistry-Climate <span class="hlt">Model</span> Initiative and Aer-Chem-MIP. From a total dataset of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regional background locations that are appropriate for use in global <span class="hlt">model</span> evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This dataset is made available for the purposes of <span class="hlt">model</span> evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily eight-hour average (MDA8), SOMO35, AOT40, and metrics related to air quality regulatory thresholds. Gridded datasets are stored as netCDF-4 files and are available to download from the British <span class="hlt">Atmospheric</span> Data Centre (doi:<a href="http://dx.doi.org/10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452">10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452</a>). We provide recommendations to the ozone measurement <span class="hlt">community</span> regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ESSD....8...41S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ESSD....8...41S"><span>Gridded global surface ozone metrics for <span class="hlt">atmospheric</span> chemistry <span class="hlt">model</span> evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sofen, E. D.; Bowdalo, D.; Evans, M. J.; Apadula, F.; Bonasoni, P.; Cupeiro, M.; Ellul, R.; Galbally, I. E.; Girgzdiene, R.; Luppo, S.; Mimouni, M.; Nahas, A. C.; Saliba, M.; Tørseth, K.</p> <p>2016-02-01</p> <p>The concentration of ozone at the Earth's surface is measured at many locations across the globe for the purposes of air quality monitoring and <span class="hlt">atmospheric</span> chemistry research. We have brought together all publicly available surface ozone observations from online databases from the modern era to build a consistent data set for the evaluation of chemical transport and chemistry-climate (Earth System) <span class="hlt">models</span> for projects such as the Chemistry-Climate <span class="hlt">Model</span> Initiative and Aer-Chem-MIP. From a total data set of approximately 6600 sites and 500 million hourly observations from 1971-2015, approximately 2200 sites and 200 million hourly observations pass screening as high-quality sites in regionally representative locations that are appropriate for use in global <span class="hlt">model</span> evaluation. There is generally good data volume since the start of air quality monitoring networks in 1990 through 2013. Ozone observations are biased heavily toward North America and Europe with sparse coverage over the rest of the globe. This data set is made available for the purposes of <span class="hlt">model</span> evaluation as a set of gridded metrics intended to describe the distribution of ozone concentrations on monthly and annual timescales. Metrics include the moments of the distribution, percentiles, maximum daily 8-hour average (MDA8), sum of means over 35 ppb (daily maximum 8-h; SOMO35), accumulated ozone exposure above a threshold of 40 ppbv (AOT40), and metrics related to air quality regulatory thresholds. Gridded data sets are stored as netCDF-4 files and are available to download from the British <span class="hlt">Atmospheric</span> Data Centre (doi: 10.5285/08fbe63d-fa6d-4a7a-b952-5932e3ab0452). We provide recommendations to the ozone measurement <span class="hlt">community</span> regarding improving metadata reporting to simplify ongoing and future efforts in working with ozone data from disparate networks in a consistent manner.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016DPS....4812235L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016DPS....4812235L"><span>1-D Radiative-Convective <span class="hlt">Model</span> for Terrestrial Exoplanet <span class="hlt">Atmospheres</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leung, Cecilia W. S.; Robinson, Tyler D.</p> <p>2016-10-01</p> <p>We present a one dimensional radiative-convective <span class="hlt">model</span> to study the thermal structure of terrestrial exoplanetary <span class="hlt">atmospheres</span>. The radiative transfer and equilibrium chemistry in our <span class="hlt">model</span> is based on similar methodologies in <span class="hlt">models</span> used for studying Extrasolar Giant Planets (Fortney et al. 2005b.) We validated our <span class="hlt">model</span> in the optically thin and thick limits, and compared our pressure-temperature profiles against the analytical solutions of Robinson & Catling (2012). For extrasolar terrestrial planets with pure hydrogen <span class="hlt">atmospheres</span>, we evaluated the effects of H2-H2 collision induced absorption and identified the purely roto-translational band in our <span class="hlt">modeled</span> spectra. We also examined how enhanced <span class="hlt">atmospheric</span> metallicities affect the temperature structure, chemistry, and spectra of terrestrial exoplanets. For a terrestrial extrasolar planet whose <span class="hlt">atmospheric</span> compostion is 100 times solar orbiting a sun-like star at 2 AU, our <span class="hlt">model</span> resulted in a reducing <span class="hlt">atmosphere</span> with H2O, CH4, and NH3 as the dominant greenhouse gases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760004021','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760004021"><span><span class="hlt">Modelling</span> <span class="hlt">atmospheric</span> turbulence for a motion-based simulator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jacobson, I. D.; Joshi, D.</p> <p>1975-01-01</p> <p>The background information in establishing several proposed <span class="hlt">atmospheric</span> turbulence <span class="hlt">models</span> for use on motion based aircraft simulators was documented. A specific <span class="hlt">model</span> was proposed which, in addition to varying turbulence intensity (rms velocity), varies the <span class="hlt">atmospheric</span> turbulence scale length to achieve compatibility with real <span class="hlt">atmospheric</span> turbulence. With a suitable combination of scale length and intensity distribution, the <span class="hlt">model</span> will simulate various <span class="hlt">atmospheric</span> conditions characterized by altitude, stability, and terrain. The <span class="hlt">model</span> is mechanized to be included in a flight simulator experiment in order to determine to what extent the pilots are sensitive to changes in <span class="hlt">atmospheric</span> conditions and the realism of the <span class="hlt">model</span>. The following topics were covered: literature survey, presently used techniques, proposed <span class="hlt">model</span>, and simulation details.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920043123&hterms=adm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dadm','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920043123&hterms=adm&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dadm"><span><span class="hlt">Atmospheric</span> disturbance <span class="hlt">model</span> for aircraft and space capable vehicles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chimene, Beau C.; Park, Young W.; Bielski, W. P.; Shaughnessy, John D.; Mcminn, John D.</p> <p>1992-01-01</p> <p>An <span class="hlt">atmospheric</span> disturbance <span class="hlt">model</span> (ADM) is developed that considers the requirements of advanced aerospace vehicles and balances algorithmic assumptions with computational constraints. The requirements for an ADM include a realistic power spectrum, inhomogeneity, and the cross-correlation of <span class="hlt">atmospheric</span> effects. The baseline <span class="hlt">models</span> examined include the Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Perturbation-<span class="hlt">Modeling</span> Technique, the Dryden Small-Scale Turbulence Description, and the Patchiness <span class="hlt">Model</span>. The Program to Enhance Random Turbulence (PERT) is developed based on the previous <span class="hlt">models</span> but includes a revised formulation of large-scale <span class="hlt">atmospheric</span> disturbance, an inhomogeneous Dryden filter, turbulence statistics, and the cross-correlation between Dryden Turbulence Filters and small-scale thermodynamics. Verification with the Monte Carlo approach demonstrates that the PERT software provides effective simulations of inhomogeneous <span class="hlt">atmospheric</span> parameters.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740012378','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740012378"><span>Atomic hydrogen distribution. [in Titan <span class="hlt">atmospheric</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tabarie, N.</p> <p>1974-01-01</p> <p>Several possible H2 vertical distributions in Titan's <span class="hlt">atmosphere</span> are considered with the constraint of 5 km-A a total quantity. Approximative calculations show that hydrogen distribution is quite sensitive to two other parameters of Titan's <span class="hlt">atmosphere</span>: the temperature and the presence of other constituents. The escape fluxes of H and H2 are also estimated as well as the consequent distributions trapped in the Saturnian system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170001621','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170001621"><span><span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> Using Accelerometer Data During Mars <span class="hlt">Atmosphere</span> and Volatile Evolution (MAVEN) Flight Operations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tolson, Robert H.; Lugo, Rafael A.; Baird, Darren T.; Cianciolo, Alicia D.; Bougher, Stephen W.; Zurek, Richard M.</p> <p>2017-01-01</p> <p>The Mars <span class="hlt">Atmosphere</span> and Volatile EvolutioN (MAVEN) spacecraft is a NASA orbiter designed to explore the Mars upper <span class="hlt">atmosphere</span>, typically from 140 to 160 km altitude. In addition to the nominal science mission, MAVEN has performed several Deep Dip campaigns in which the orbit's closest point of approach, also called periapsis, was lowered to an altitude range of 115 to 135 km. MAVEN accelerometer data were used during mission operations to estimate <span class="hlt">atmospheric</span> parameters such as density, scale height, along-track gradients, and wave structures. Density and scale height estimates were compared against those obtained from the Mars Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> and used to aid the MAVEN navigation team in planning maneuvers to raise and lower periapsis during Deep Dip operations. This paper describes the processes used to reconstruct <span class="hlt">atmosphere</span> parameters from accelerometers data and presents the results of their comparison to <span class="hlt">model</span> and navigation-derived values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336753&showcriteria=2&fed_org_id=111&timstype=published+report&datebeginpublishedpresented=07/20/2012&dateendpublishedpresented=07/20/2017&sortby=pubdateyear','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=336753&showcriteria=2&fed_org_id=111&timstype=published+report&datebeginpublishedpresented=07/20/2012&dateendpublishedpresented=07/20/2017&sortby=pubdateyear"><span>Global <span class="hlt">Atmosphere</span> Watch Workshop on Measurement-<span class="hlt">Model</span> ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>The World Meteorological Organization’s (WMO) Global <span class="hlt">Atmosphere</span> Watch (GAW) Programme coordinates high-quality observations of <span class="hlt">atmospheric</span> composition from global to local scales with the aim to drive high-quality and high-impact science while co-producing a new generation of products and services. In line with this vision, GAW’s Scientific Advisory Group for Total <span class="hlt">Atmospheric</span> Deposition (SAG-TAD) has a mandate to produce global maps of wet, dry and total <span class="hlt">atmospheric</span> deposition for important <span class="hlt">atmospheric</span> chemicals to enable research into biogeochemical cycles and assessments of ecosystem and human health effects. The most suitable scientific approach for this activity is the emerging technique of measurement-<span class="hlt">model</span> fusion for total <span class="hlt">atmospheric</span> deposition. This technique requires global-scale measurements of <span class="hlt">atmospheric</span> trace gases, particles, precipitation composition and precipitation depth, as well as predictions of the same from global/regional chemical transport <span class="hlt">models</span>. The fusion of measurement and <span class="hlt">model</span> results requires data assimilation and mapping techniques. The objective of the GAW Workshop on Measurement-<span class="hlt">Model</span> Fusion for Global Total <span class="hlt">Atmospheric</span> Deposition (MMF-GTAD), an initiative of the SAG-TAD, was to review the state-of-the-science and explore the feasibility and methodology of producing, on a routine retrospective basis, global maps of <span class="hlt">atmospheric</span> gas and aerosol concentrations as well as wet, dry and total deposition via measurement-<span class="hlt">model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910018329','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910018329"><span>Proposed reference <span class="hlt">models</span> for atomic oxygen in the terrestrial <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Llewellyn, E. J.; Mcdade, I. C.; Lockerbie, M. D.</p> <p>1989-01-01</p> <p>A provisional Atomic Oxygen Reference <span class="hlt">model</span> was derived from average monthly ozone profiles and the MSIS-86 reference <span class="hlt">model</span> <span class="hlt">atmosphere</span>. The concentrations are presented in tabular form for the altitude range 40 to 130 km.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A33A0186S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A33A0186S"><span>Inverse <span class="hlt">modeling</span> of global <span class="hlt">atmospheric</span> carbon dioxide by Global Eulerian-Lagrangian Coupled <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (GELCA)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shirai, T.; Ishizawa, M.; Zhuravlev, R.; Ganshin, A.; Belikov, D.; Saito, M.; Oda, T.; Valsala, V.; Dlugokencky, E. J.; Tans, P. P.; Maksyutov, S. S.</p> <p>2013-12-01</p> <p>Global monthly CO2 flux distributions for 2001-2011 were estimated using an <span class="hlt">atmospheric</span> inverse <span class="hlt">modeling</span> system, which is based on combination of two transport <span class="hlt">models</span>, called GELCA (Global Eulerian-Lagrangian Coupled <span class="hlt">Atmospheric</span> <span class="hlt">model</span>). This coupled <span class="hlt">model</span> approach has several advantages over inversions to a single <span class="hlt">model</span> alone: the use of Lagrangian particle dispersion <span class="hlt">model</span> (LPDM) to simulate the transport in the vicinity of the observation points enables us to avoid numerical diffusion of Eulerian <span class="hlt">models</span>, and is suitable to represent observations at high spatial and temporal resolutions. The global background concentration field generated by an Eulerian <span class="hlt">model</span> is used as time-variant boundary conditions for an LPDM that performs backward simulations from each receptor point (observation event). In the GELCA inversion system, National Institute for Environmental Studies-Transport <span class="hlt">Model</span> (NIES-TM) version 8.1i was used as an Eulerian global transport <span class="hlt">model</span> coupled with FLEXPART version 8.0 as an LPDM. The meteorological fields for driving both <span class="hlt">models</span> were taken from JMA Climate Data Assimilation System (JCDAS) with a spatial resolution of 1.25° x 1.25°, 40 vertical levels and a temporal resolution of 6 hours. Our prior CO2 fluxes consist of daily terrestrial biospheric fluxes, monthly oceanic fluxes, monthly biomass burning emissions, and monthly fossil fuel CO2 emissions. We employed a Kalman Smoother optimization technique with fixed lag of 3 months, estimating monthly CO2 fluxes for 42 land and 22 ocean regions. We have been using two different global networks of CO2 observations. The Observation Package (ObsPack) data products contain more measurement information in space and time than the NOAA global cooperative air sampling network which basically consists of approximately weekly sampling at background sites. The global total flux and its large-scale distribution optimized with two different global observation networks agreed overall with other previous</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED451814.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED451814.pdf"><span><span class="hlt">Modeling</span> <span class="hlt">Community</span> through Cohort Development.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Basom, Margaret R.; Yerkes, Diane M.</p> <p></p> <p>This paper explores the nature of the curriculum within learning <span class="hlt">communities</span>, specifically, learning <span class="hlt">communities</span> in leadership preparation programs. It also addresses how cohorts of learning <span class="hlt">communities</span> operate effectively as cohesive groups, and how they, in turn, promote the enhancement of individuals. The process curriculum advocated in this…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.H11B1269L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.H11B1269L"><span>Evaluation of <span class="hlt">Community</span> Land <span class="hlt">Model</span> Hydrologic Predictions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, K. Y.; Lettenmaier, D. P.; Bohn, T.; Delire, C.</p> <p>2005-12-01</p> <p>Confidence in representation and parameterization of land surface processes in coupled land-<span class="hlt">atmosphere</span> <span class="hlt">models</span> is strongly dependent on a diversity of opportunities for <span class="hlt">model</span> testing, since such coupled <span class="hlt">models</span> are usually intended for application in a wide range of conditions (regional <span class="hlt">models</span>) or globally. Land surface <span class="hlt">models</span> have been increasing in complexity over the past decade, which has increased the demands on data sets appropriate for <span class="hlt">model</span> testing and evaluation. In this study, we compare the performance of two commonly used land surface schemes - the Variable Infiltration Capacity (VIC) and <span class="hlt">Community</span> Land <span class="hlt">Model</span> (CLM) with respect to their ability to reproduce observed water and energy fluxes in off-line tests for two large river basins with contrasting hydroclimatic conditions spanning the range from temperate continental to arctic, and for five point (column flux) sites spanning the range from tropical to arctic. The two large river basins are the Arkansas-Red in U.S. southern Great Plains, and the Torne-Kalix in northern Scandinavia. The column flux evaluations are for a tropical forest site at Reserva Jaru (ABRACOS) in Brazil, a prairie site (FIFE) near Manhattan, Kansas in the central U.S., a soybean site at Caumont (HAPEX-Monbilhy) in France, a meadow site at Cabauw in the Netherlands, and a small grassland catchment at Valday, Russia. The results indicate that VIC can reasonably well capture the land surface biophysical processes, while CLM is somewhat less successful. We suggest changes to the CLM parameterizations that would improve its general performance with respect to its representation of land surface hydrologic processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.......264B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.......264B"><span>Multiscale <span class="hlt">Modeling</span> of Microbial <span class="hlt">Communities</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blanchard, Andrew</p> <p></p> <p>Although bacteria are single-celled organisms, they exist in nature primarily in the form of complex <span class="hlt">communities</span>, participating in a vast array of social interactions through regulatory gene networks. The social interactions between individual cells drive the emergence of <span class="hlt">community</span> structures, resulting in an intricate relationship across multiple spatiotemporal scales. Here, I present my work towards developing and applying the tools necessary to <span class="hlt">model</span> the complex dynamics of bacterial <span class="hlt">communities</span>. In Chapter 2, I utilize a reaction-diffusion <span class="hlt">model</span> to determine the population dynamics for a population with two species. One species (CDI+) utilizes contact dependent inhibition to kill the other sensitive species (CDI-). The competition can produce diverse patterns, including extinction, coexistence, and localized aggregation. The emergence, relative abundance, and characteristic features of these patterns are collectively determined by the competitive benefit of CDI and its growth disadvantage for a given rate of population diffusion. The results provide a systematic and statistical view of CDI-based bacterial population competition, expanding the spectrum of our knowledge about CDI systems and possibly facilitating new experimental tests for a deeper understanding of bacterial interactions. In the following chapter, I present a systematic computational survey on the relationship between social interaction types and population structures for two-species <span class="hlt">communities</span> by developing and utilizing a hybrid computational framework that combines discrete element techniques with reaction-diffusion equations. The impact of deleterious and beneficial interactions on the <span class="hlt">community</span> are quantified. Deleterious interactions generate an increased variance in relative abundance, a drastic decrease in surviving lineages, and a rough expanding front. In contrast, beneficial interactions contribute to a reduced variance in relative abundance, an enhancement in lineage number, and a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/465720','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/465720"><span><span class="hlt">Modeling</span> the effects of <span class="hlt">atmospheric</span> emissions on groundwater composition</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brown, Theresa Jean</p> <p>1994-01-01</p> <p>A composite <span class="hlt">model</span> of <span class="hlt">atmospheric</span>, unsaturated and groundwater transport is developed to evaluate the processes determining the distribution of <span class="hlt">atmospherically</span> derived contaminants in groundwater systems and to test the sensitivity of simulated contaminant concentrations to input parameters and <span class="hlt">model</span> linkages. One application is to screen specific <span class="hlt">atmospheric</span> emissions for their potential in determining groundwater age. Temporal changes in <span class="hlt">atmospheric</span> emissions could provide a recognizable pattern in the groundwater system. The <span class="hlt">model</span> also provides a way for quantifying the significance of uncertainties in the tracer source term and transport parameters on the contaminant distribution in the groundwater system, an essential step in using the distribution of contaminants from local, point source <span class="hlt">atmospheric</span> emissions to examine conceptual <span class="hlt">models</span> of groundwater flow and transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1106132.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1106132.pdf"><span>The Jeffrey Town <span class="hlt">Model</span> for <span class="hlt">Community</span> Development</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Gordon, Ivy Veronica</p> <p>2014-01-01</p> <p>The Jeffrey Town <span class="hlt">model</span> for <span class="hlt">community</span> development has been effectively applied to the rural <span class="hlt">community</span> of Jeffrey Town in Jamaica with Information and Computer Technology (ICT) as a key element. The farmer's association is the vehicle that has driven the change. Included is a brief outline of the <span class="hlt">community</span> plus highlights of the tangible and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED414502.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED414502.pdf"><span><span class="hlt">Community</span> Capacity and Resource Mapping: <span class="hlt">Model</span> Development.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Dedrick, Angie; Mitchell, Graham</p> <p></p> <p>This document explains the use of a <span class="hlt">model</span> for mapping <span class="hlt">community</span> capacity and resources that was developed by the <span class="hlt">community</span> development office of a health group in Edmonton, Alberta, and applied in a collaborative pilot project in preparation for development of a <span class="hlt">community</span> health plan. A brief discussion of the factors leading to development of the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1982PhDT........52H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1982PhDT........52H"><span>A <span class="hlt">Atmospheric</span> Dispersion <span class="hlt">Model</span> for the Sudbury, Ontario, Area.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huhn, Frank Jones</p> <p>1982-03-01</p> <p>A mathematical <span class="hlt">model</span> was developed and tested to predict the relationship between sulphur oxide and trace metal emissions from smelters in the Sudbury, Ontario area, and <span class="hlt">atmospheric</span>, precipitation, lake water and sediment chemistry. The <span class="hlt">model</span> consists of <span class="hlt">atmospheric</span> and lake chemistry portions. The <span class="hlt">atmospheric</span> <span class="hlt">model</span> is a Gaussian crosswind concentration distribution modification to a box <span class="hlt">model</span> with a uniform vertical concentration gradient limited by a mixing height. In the near-field Briggs' plume rise and vertical dispersion terms are utilized. Oxidation, wet and dry deposition mechanisms are included to account for the gas, liquid and solid phases separately. Important improvements over existing <span class="hlt">models</span> include (1) near- and far-field conditions treated in a single <span class="hlt">model</span>; (2) direct linkage of crosswind dispersion to hourly meteorological observations; (3) utilization of maximum to minimum range of input parameters to realistically <span class="hlt">model</span> the range of outputs; (4) direct linkage of the <span class="hlt">atmospheric</span> <span class="hlt">model</span> to a lake <span class="hlt">model</span>. Precipitation chemistry as calculated by the <span class="hlt">atmospheric</span> <span class="hlt">model</span> is related to lake water and sediment chemistry utilizing a mass balance approach and assuming a continuously stirred reactor (CSTR) <span class="hlt">model</span> to describe lake circulation. All inputs are <span class="hlt">atmospheric</span>, modified by hydrology, soil chemistry and sedimentation. <span class="hlt">Model</span> results were tested by comparison with existing <span class="hlt">atmospheric</span> and precipitation chemistry measurements, supplemented with analyses of lake water and sediment chemistry collected in a field program. Eight pollutant species were selected for <span class="hlt">modeling</span>: sulphur dioxide, sulphate ion, hydrogen ion, copper, nickel, lead, zinc, and iron. The <span class="hlt">model</span> effectively predicts precipitation chemistry within 150 km of Sudbury, with an average prediction to measurement ratio of 90 percent. <span class="hlt">Atmospheric</span> concentrations are effectively predicted within 80 km, with an average prediction to measurement ratio of 81 percent. Lake chemistry predictions are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Harbour&pg=5&id=EJ665005','ERIC'); return false;" href="https://eric.ed.gov/?q=Harbour&pg=5&id=EJ665005"><span>An Institutional Accountability <span class="hlt">Model</span> for <span class="hlt">Community</span> Colleges.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Harbour, Clifford P.</p> <p>2003-01-01</p> <p>Proposes a <span class="hlt">model</span> for managing a <span class="hlt">community</span> college's accountability environment and shows how it can be applied. Reports that the <span class="hlt">model</span> is premised on the pluralistic perspective of accountability (Kearns), and uses Christensen's value network for building the <span class="hlt">community</span> college <span class="hlt">model</span>. (Contains 37 references.) (AUTH/NB)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1513455P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1513455P"><span>The balance <span class="hlt">model</span> of oxygen enrichment of <span class="hlt">atmospheric</span> air</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Popov, Alexander</p> <p>2013-04-01</p> <p>The study of turnover of carbon and oxygen is an important line of scientific investigation. This line takes on special significance in conditions of soil degradation, which leads to the excess content of carbon dioxide and, as result, decrease of oxygen in the <span class="hlt">atmosphere</span>. The aim of this article is a statement the balance <span class="hlt">model</span> of oxygen enrichment of <span class="hlt">atmospheric</span> air (ratio O/C) depending on consumption and assimilation by plants of dissolved organic matter (DOM) and the value of the oxidation-reduction potential (Eh). Basis of <span class="hlt">model</span> was the following: green vascular plants are facultative heterotrophic organisms with symbiotic digestion and nutrition. According to the trophology viewpoint, the plant consumption of organic compounds broadens greatly a notion about the plant nutrition and ways of its regulation. In particular, beside the main known cycle of carbon: plant - litter - humus - carbon dioxide - plant, there is the second carbon cycle (turnover of organic compounds): plant - litter - humus - DOM - plant. The biogeochemical meaning of consumption of organic compounds by plants is that plants build the structural and functional blocks of biological macromolecules in their bodies. It provides receiving of a certain "energy payoff" by plants, which leads to increase of plant biomass by both an inclusion of allochthonous organic molecules in plant tissues, and positive effect of organic compounds on plant metabolic processes. One more of powerful ecological consequence of a heterotrophic nutrition of green plants is oxygen enrichment of <span class="hlt">atmospheric</span> air. As the organic molecules in the second biological cycle of carbon are built in plants without considerable chemical change, the <span class="hlt">atmospheric</span> air is enriched on that amount of oxygen, which would be required on oxidation of the organic molecules absorbed by plants, in result. It was accepted that: plant-soil system was climax, the plant <span class="hlt">community</span> was grassy, initial contents of carbon in phytomass was accepted</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/35021','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/35021"><span>Microbial <span class="hlt">community</span> composition and function beneath temperate trees exposed to elevated <span class="hlt">atmospheric</span> carbon dioxide and ozone</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Rebecca L. Phillips; Donald R. Zak; William E. Holmes; David C. White</p> <p>2002-01-01</p> <p>We hypothesized that changes in plant growth resulting from <span class="hlt">atmospheric</span> CO2 and O3 enrichment would alter the flow of C through soil food webs and that this effect would vary with tree species. To test this idea, we traced the course of C through the soil microbial <span class="hlt">community</span> using soils from the free-air CO2...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/17310','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/17310"><span>Productivity and <span class="hlt">community</span> structure of ectomycorrhizal fungal sporocarps under increased <span class="hlt">atmospheric</span> CO2 and O3</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Carrie Andrew; Erik A. Lilleskov</p> <p>2009-01-01</p> <p>Sporocarp production is essential for ectomycorrhizal fungal recombination and dispersal, which influences fungal <span class="hlt">community</span> dynamics. Increasing <span class="hlt">atmospheric</span> carbon dioxide (CO2) and ozone (O3) affect host plant carbon gain and allocation, which may in turn influence ectomycorrhizal sporocarp production if the carbon...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=294453','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=294453"><span>Fungal <span class="hlt">community</span> responses to past and future <span class="hlt">atmospheric</span> CO2 differ by soil type</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>Soils sequester and release substantial <span class="hlt">atmospheric</span> carbon, but the biological responses of soils to rising CO2 are not well understood. We studied fungal <span class="hlt">communities</span> in a grassland ecosystem exposed to a preindustrial-to-future CO2 gradient (250-500 ppm) on two soil types, a black clay and a sandy...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017isms.confEMJ07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017isms.confEMJ07B"><span><span class="hlt">Atmospheric</span> Isotopologues Observed with Ace-Fts and <span class="hlt">Modeled</span> with Waccm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Buzan, Eric M.; Beale, Christopher A.; Yousefi, Mahdi; Boone, Chris; Bernath, Peter F.</p> <p>2017-06-01</p> <p><span class="hlt">Atmospheric</span> isotopologues are useful tracers of dynamics and chemistry and can be used to constrain budgets of gases in the <span class="hlt">atmosphere</span>. The <span class="hlt">Atmospheric</span> Chemistry Experiment (ACE) routinely measures vertical profiles of over 35 molecules and 20 isotopologues via solar occultation from a satellite in low Earth orbit. The primary instrument is an infrared Fourier transform spectrometer with a spectral range of 750 - 4400 \\wn and a resolution of 0.02 \\wn. ACE began taking measurements in 2004 and is still active today. This talk focuses on isotopic measurements of CH_{4}, CO, CO_{2}, and N_{2}O from ACE-FTS. To complement ACE-FTS data, <span class="hlt">modeling</span> using the Whole <span class="hlt">Atmosphere</span> <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (WACCM) was performed for each molecule.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740012367','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740012367"><span>Scientific summary. [composition of Titan <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hunten, D. M.</p> <p>1974-01-01</p> <p>Methane absorptions are prominent in the Titan <span class="hlt">atmospheric</span> spectrum; also present are atomic hydrogen and nitrogen bands. Evaluation of the low ultraviolet albedo points to solid methane clouds and photochemical haze. Thermal infrared data indicate solar energy absorption and photodissociation reactions of the gas mixture resulting in the production of organic compounds and free hydrogen atoms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990062656','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990062656"><span><span class="hlt">Modelling</span> <span class="hlt">Atmospheric</span> Scattering Using Spacecraft Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rages, Kathy A.</p> <p>1999-01-01</p> <p>The period covered by this cooperative agreement included the analysis of data from the Voyager encounter with Neptune and Triton and the primary Galileo mission to Jupiter (including the Galileo Probe entry into Jupiter's <span class="hlt">atmosphere</span>), as well as continued work on Uranus' seasonal variability using the Voyager encounter data as a baseline.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790061925&hterms=Electricity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectricity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790061925&hterms=Electricity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectricity"><span>A quasi-static <span class="hlt">model</span> of global <span class="hlt">atmospheric</span> electricity. I - The lower <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hays, P. B.; Roble, R. G.</p> <p>1979-01-01</p> <p>A quasi-steady <span class="hlt">model</span> of global lower <span class="hlt">atmospheric</span> electricity is presented. The <span class="hlt">model</span> considers thunderstorms as dipole electric generators that can be randomly distributed in various regions and that are the only source of <span class="hlt">atmospheric</span> electricity and includes the effects of orography and electrical coupling along geomagnetic field lines in the ionosphere and magnetosphere. The <span class="hlt">model</span> is used to calculate the global distribution of electric potential and current for <span class="hlt">model</span> conductivities and assumed spatial distributions of thunderstorms. Results indicate that large positive electric potentials are generated over thunderstorms and penetrate to ionospheric heights and into the conjugate hemisphere along magnetic field lines. The perturbation of the calculated electric potential and current distributions during solar flares and subsequent Forbush decreases is discussed, and future measurements of <span class="hlt">atmospheric</span> electrical parameters and modifications of the <span class="hlt">model</span> which would improve the agreement between calculations and measurements are suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790061925&hterms=electricity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Delectricity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790061925&hterms=electricity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Delectricity"><span>A quasi-static <span class="hlt">model</span> of global <span class="hlt">atmospheric</span> electricity. I - The lower <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hays, P. B.; Roble, R. G.</p> <p>1979-01-01</p> <p>A quasi-steady <span class="hlt">model</span> of global lower <span class="hlt">atmospheric</span> electricity is presented. The <span class="hlt">model</span> considers thunderstorms as dipole electric generators that can be randomly distributed in various regions and that are the only source of <span class="hlt">atmospheric</span> electricity and includes the effects of orography and electrical coupling along geomagnetic field lines in the ionosphere and magnetosphere. The <span class="hlt">model</span> is used to calculate the global distribution of electric potential and current for <span class="hlt">model</span> conductivities and assumed spatial distributions of thunderstorms. Results indicate that large positive electric potentials are generated over thunderstorms and penetrate to ionospheric heights and into the conjugate hemisphere along magnetic field lines. The perturbation of the calculated electric potential and current distributions during solar flares and subsequent Forbush decreases is discussed, and future measurements of <span class="hlt">atmospheric</span> electrical parameters and modifications of the <span class="hlt">model</span> which would improve the agreement between calculations and measurements are suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080013597','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080013597"><span>Earth Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> 2007 (Earth-GRAM07) Applications for the NASA Constellation Program</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leslie, Fred W.; Justus, C. G.</p> <p>2008-01-01</p> <p>Engineering <span class="hlt">models</span> of the <span class="hlt">atmosphere</span> are used extensively by the aerospace <span class="hlt">community</span> for design issues related to vehicle ascent and descent. The Earth Global Reference <span class="hlt">Atmosphere</span> <span class="hlt">Model</span> version 2007 (Earth-GRAM07) is the latest in this series and includes a number of new features. Like previous versions, Earth-GRAM07 provides both mean values and perturbations for density, temperature, pressure, and winds, as well as monthly- and geographically-varying trace constituent concentrations. From 0 km to 27 km, thermodynamics and winds are based on the National Oceanic and <span class="hlt">Atmospheric</span> Administration Global Upper Air Climatic Atlas (GUACA) climatology. For altitudes between 20 km and 120 km, the <span class="hlt">model</span> uses data from the Middle <span class="hlt">Atmosphere</span> Program (MAP). Above 120 km, EarthGRAM07 now provides users with a choice of three thermosphere <span class="hlt">models</span>: the Marshall Engineering Thermosphere (MET-2007) <span class="hlt">model</span>; the Jacchia-Bowman 2006 thermosphere <span class="hlt">model</span> (JB2006); and the Naval Research Labs Mass Spectrometer, Incoherent Scatter Radar Extended <span class="hlt">Model</span> (NRL MSIS E-OO) with the associated Harmonic Wind <span class="hlt">Model</span> (HWM-93). In place of these datasets, Earth-GRAM07 has the option of using the new 2006 revised Range Reference <span class="hlt">Atmosphere</span> (RRA) data, the earlier (1983) RRA data, or the user may also provide their own data as an auxiliary profile. Refinements of the perturbation <span class="hlt">model</span> are also discussed which include wind shears more similar to those observed at the Kennedy Space Center than the previous version Earth-GRAM99.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1043034','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1043034"><span>COLLABORATIVE RESEARCH: CONTINUOUS DYNAMIC GRID ADAPTATION IN A GLOBAL <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span>: APPLICATION AND REFINEMENT</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Prusa, Joseph</p> <p>2012-05-08</p> <p>This project had goals of advancing the performance capabilities of the numerical general circulation <span class="hlt">model</span> EULAG and using it to produce a fully operational <span class="hlt">atmospheric</span> global climate <span class="hlt">model</span> (AGCM) that can employ either static or dynamic grid stretching for targeted phenomena. The resulting AGCM combined EULAG's advanced dynamics core with the physics of the NCAR <span class="hlt">Community</span> <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (CAM). Effort discussed below shows how we improved <span class="hlt">model</span> performance and tested both EULAG and the coupled CAM-EULAG in several ways to demonstrate the grid stretching and ability to simulate very well a wide range of scales, that is, multi-scale capability. We leveraged our effort through interaction with an international EULAG <span class="hlt">community</span> that has collectively developed new features and applications of EULAG, which we exploited for our own work summarized here. Overall, the work contributed to over 40 peer- reviewed publications and over 70 conference/workshop/seminar presentations, many of them invited.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GMD.....6..495D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GMD.....6..495D"><span><span class="hlt">Modeling</span> agriculture in the <span class="hlt">Community</span> Land <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Drewniak, B.; Song, J.; Prell, J.; Kotamarthi, V. R.; Jacob, R.</p> <p>2013-04-01</p> <p>The potential impact of climate change on agriculture is uncertain. In addition, agriculture could influence above- and below-ground carbon storage. Development of <span class="hlt">models</span> that represent agriculture is necessary to address these impacts. We have developed an approach to integrate agriculture representations for three crop types - maize, soybean, and spring wheat - into the coupled carbon-nitrogen version of the <span class="hlt">Community</span> Land <span class="hlt">Model</span> (CLM), to help address these questions. Here we present the new <span class="hlt">model</span>, CLM-Crop, validated against observations from two AmeriFlux sites in the United States, planted with maize and soybean. Seasonal carbon fluxes compared well with field measurements for soybean, but not as well for maize. CLM-Crop yields were comparable with observations in countries such as the United States, Argentina, and China, although the generality of the crop <span class="hlt">model</span> and its lack of technology and irrigation made direct comparison difficult. CLM-Crop was compared against the standard CLM3.5, which simulates crops as grass. The comparison showed improvement in gross primary productivity in regions where crops are the dominant vegetation cover. Crop yields and productivity were negatively correlated with temperature and positively correlated with precipitation, in agreement with other <span class="hlt">modeling</span> studies. In case studies with the new crop <span class="hlt">model</span> looking at impacts of residue management and planting date on crop yield, we found that increased residue returned to the litter pool increased crop yield, while reduced residue returns resulted in yield decreases. Using climate controls to signal planting date caused different responses in different crops. Maize and soybean had opposite reactions: when low temperature threshold resulted in early planting, maize responded with a loss of yield, but soybean yields increased. Our improvements in CLM demonstrate a new capability in the <span class="hlt">model</span> - simulating agriculture in a realistic way, complete with fertilizer and residue management</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/656663','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/656663"><span>[Development of <span class="hlt">model</span> <span class="hlt">communities</span> (Cool <span class="hlt">Communities</span>)]. Final report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p></p> <p>1998-09-01</p> <p>This report covers progress in the Cool <span class="hlt">Communities</span> program and is intended to detail specific accomplishments during the year and to provide a limited amount of background information about the program and its progress over the past three years. The Cool <span class="hlt">Communities</span> project is driven by local partnerships among business, citizens, government, and guided by a Local Advisory Committee of representatives from these organizations. A national overview of the program is given in the first section. The second section describes specific accomplishments in each of the <span class="hlt">model</span> <span class="hlt">communities</span> in Dade County, Atlanta, Frederick, Tucson, Springfield, Austin, and the Davis Monthan Air Force Base.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.H51I1635L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.H51I1635L"><span>Evaluating Land-<span class="hlt">Atmosphere</span> Moisture Feedbacks in Earth System <span class="hlt">Models</span> With Spaceborne Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Levine, P. A.; Randerson, J. T.; Lawrence, D. M.; Swenson, S. C.</p> <p>2016-12-01</p> <p>We have developed a set of metrics for measuring the feedback loop between the land surface moisture state and the <span class="hlt">atmosphere</span> globally on an interannual time scale. These metrics consider both the forcing of terrestrial water storage (TWS) on subsequent <span class="hlt">atmospheric</span> conditions as well as the response of TWS to antecedent <span class="hlt">atmospheric</span> conditions. We designed our metrics to take advantage of more than one decade's worth of satellite observations of TWS from the Gravity Recovery and Climate Experiment (GRACE) along with <span class="hlt">atmospheric</span> variables from the <span class="hlt">Atmospheric</span> Infrared Sounder (AIRS), the Global Precipitation Climatology Project (GPCP), and Clouds and the Earths Radiant Energy System (CERES). Metrics derived from spaceborne observations were used to evaluate the strength of the feedback loop in the <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM) Large Ensemble (LENS) and in several <span class="hlt">models</span> that contributed simulations to Phase 5 of the Coupled <span class="hlt">Model</span> Intercomparison Project (CMIP5). We found that both forcing and response limbs of the feedback loop were generally stronger in tropical and temperate regions in CMIP5 <span class="hlt">models</span> and even more so in LENS compared to satellite observations. Our analysis suggests that <span class="hlt">models</span> may overestimate the strength of the feedbacks between the land surface and the <span class="hlt">atmosphere</span>, which is consistent with previous studies conducted across different spatial and temporal scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20050180353&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20050180353&hterms=defense+centers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddefense%2Bcenters"><span>Transition to Operations Support at the <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hesse, M.</p> <p>2005-01-01</p> <p>The <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather <span class="hlt">models</span>. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day <span class="hlt">modeling</span> capability for space weather purposes, and to provide <span class="hlt">models</span> for transition to the rapid prototyping centers at the space weather forecast centers. This goal requires close collaborations with and substantial involvement of the research <span class="hlt">community</span>. The physical regions to be addressed by CCMC-related activities range from the solar <span class="hlt">atmosphere</span> to the Earth's upper <span class="hlt">atmosphere</span>. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center, as well as distributed computing facilities provided by the US Air Force. CCMC also provides, to the research <span class="hlt">community</span>, access to state-of-the-art space research <span class="hlt">models</span>. This paper will focus on a status report on CCMC activities in support of <span class="hlt">model</span> transition to operations at US space weather forecasting centers. In particular, an update will be given on past and present transition activities, on developments that address operational needs, and on future opportunities for transition-to-operations support.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23734048','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23734048"><span><span class="hlt">Modelling</span> the formation of <span class="hlt">atmospheric</span> dust in brown dwarfs and planetary <span class="hlt">atmospheres</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Helling, Christiane; Fomins, Aleksejs</p> <p>2013-07-13</p> <p><span class="hlt">Atmospheric</span> dust from volcanoes, sand storms and biogenic products provides condensation seeds for water cloud formation on the Earth. Extrasolar planetary objects such as brown dwarfs and extrasolar giant planets have no comparable sources of condensation seeds. Hence, understanding cloud formation and further its implications for the climate requires a <span class="hlt">modelling</span> effort that includes the treatment of seed formation (nucleation), growth and evaporation, in addition to rain-out, mixing and gas-phase depletion. This paper discusses nucleation in the ultra-cool <span class="hlt">atmospheres</span> of brown dwarfs and extrasolar giant planets whose chemical gas-phase composition differs largely from the terrestrial <span class="hlt">atmosphere</span>. A kinetic <span class="hlt">model</span> for <span class="hlt">atmospheric</span> dust formation is described, which, in recent work, has become part of a cloud-formation <span class="hlt">model</span>. For the first time, diffusive replenishment of the upper <span class="hlt">atmosphere</span> is introduced as a source term into our <span class="hlt">model</span> equations. This paper further aims to show how experimental and computational chemistry work links into our dust-formation <span class="hlt">model</span>, which is driven by applications in extraterrestrial environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9452E..12K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9452E..12K"><span>Memory efficient <span class="hlt">atmospheric</span> effects <span class="hlt">modeling</span> for infrared scene generators</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kavak, Çaǧlar; Özsaraç, Seçkin</p> <p>2015-05-01</p> <p>The infrared (IR) energy radiated from any source passes through the <span class="hlt">atmosphere</span> before reaching the sensor. As a result, the total signature captured by the IR sensor is significantly modified by the <span class="hlt">atmospheric</span> effects. The dominant physical quantities that constitute the mentioned <span class="hlt">atmospheric</span> effects are the <span class="hlt">atmospheric</span> transmittance and the <span class="hlt">atmospheric</span> path radiance. The incoming IR radiation is attenuated by the transmittance and path radiance is added on top of the attenuated radiation. In IR scene simulations OpenGL is widely used for rendering purposes. In the literature there are studies, which <span class="hlt">model</span> the <span class="hlt">atmospheric</span> effects in an IR band using OpenGLs exponential fog <span class="hlt">model</span> as suggested by Beers law. In the standard pipeline of OpenGL, the related fog <span class="hlt">model</span> needs single equivalent OpenGL variables for the transmittance and path radiance, which actually depend on both the distance between the source and the sensor and also on the wavelength of interest. However, in the conditions where the range dependency cannot be <span class="hlt">modeled</span> as an exponential function, it is not accurate to replace the <span class="hlt">atmospheric</span> quantities with a single parameter. The introduction of OpenGL Shading Language (GLSL) has enabled the developers to use the GPU more flexible. In this paper, a novel method is proposed for the <span class="hlt">atmospheric</span> effects <span class="hlt">modeling</span> using the least squares estimation with polynomial fitting by programmable OpenGL shader programs built with GLSL. In this context, a radiative transfer <span class="hlt">model</span> code is used to obtain the transmittance and path radiance data. Then, polynomial fits are computed for the range dependency of these variables. Hence, the <span class="hlt">atmospheric</span> effects <span class="hlt">model</span> data that will be uploaded in the GPU memory is significantly reduced. Moreover, the error because of fitting is negligible as long as narrow IR bands are used.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPJWC..8902001K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPJWC..8902001K"><span><span class="hlt">Atmospheric</span> monitoring and <span class="hlt">model</span> applications at the Pierre Auger Observatory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keilhauer, Bianca</p> <p>2015-03-01</p> <p>The Pierre Auger Observatory detects high-energy cosmic rays with energies above ˜1017 eV. It is built as a multi-hybrid detector measuring extensive air showers with different techniques. For the reconstruction of extensive air showers, the <span class="hlt">atmospheric</span> conditions at the site of the Observatory have to be known quite well. This is particularly true for reconstructions based on data obtained by the fluorescence technique. For these data, not only the weather conditions near ground are relevant, most important are altitude-dependent <span class="hlt">atmospheric</span> profiles. The Pierre Auger Observatory has set up a dedicated <span class="hlt">atmospheric</span> monitoring programme at the site in the Mendoza province, Argentina. Beyond this, exploratory studies were performed in Colorado, USA, for possible installations in the northern hemisphere. In recent years, the <span class="hlt">atmospheric</span> monitoring programme at the Pierre Auger Observatory was supplemented by applying data from <span class="hlt">atmospheric</span> <span class="hlt">models</span>. Both GDAS and HYSPLIT are developments by the US weather department NOAA and the data are freely available. GDAS is a global <span class="hlt">model</span> of the <span class="hlt">atmospheric</span> state parameters on a 1 degree geographical grid, based on real-time measurements and numeric weather predictions, providing a full altitude-dependent data set every 3 hours. HYSPLIT is a powerful tool to track the movement of air masses at various heights, and with it the aerosols. Combining local measurements of the <span class="hlt">atmospheric</span> state variables and aerosol scattering with the given <span class="hlt">model</span> data, advanced studies about <span class="hlt">atmospheric</span> conditions can be performed and high precision air shower reconstructions are achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014IzAOP..50..111T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014IzAOP..50..111T"><span>Simulation of seasonal anomalies of <span class="hlt">atmospheric</span> circulation using coupled <span class="hlt">atmosphere</span>-ocean <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tolstykh, M. A.; Diansky, N. A.; Gusev, A. V.; Kiktev, D. B.</p> <p>2014-03-01</p> <p>A coupled <span class="hlt">atmosphere</span>-ocean <span class="hlt">model</span> intended for the simulation of coupled circulation at time scales up to a season is developed. The semi-Lagrangian <span class="hlt">atmospheric</span> general circulation <span class="hlt">model</span> of the Hydrometeorological Centre of Russia, SLAV, is coupled with the sigma <span class="hlt">model</span> of ocean general circulation developed at the Institute of Numerical Mathematics, Russian Academy of Sciences (INM RAS), INMOM. Using this coupled <span class="hlt">model</span>, numerical experiments on ensemble <span class="hlt">modeling</span> of the <span class="hlt">atmosphere</span> and ocean circulation for up to 4 months are carried out using real initial data for all seasons of an annual cycle in 1989-2010. Results of these experiments are compared to the results of the SLAV <span class="hlt">model</span> with the simple evolution of the sea surface temperature. A comparative analysis of seasonally averaged anomalies of <span class="hlt">atmospheric</span> circulation shows prospects in applying the coupled <span class="hlt">model</span> for forecasts. It is shown with the example of the El Niño phenomenon of 1997-1998 that the coupled <span class="hlt">model</span> forecasts the seasonally averaged anomalies for the period of the nonstationary El Niño phase significantly better.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28872723','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28872723"><span>Working <span class="hlt">atmosphere</span>, job satisfaction and individual characteristics of <span class="hlt">community</span> mental health professionals in integrated care.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Goetz, Katja; Kleine-Budde, Katja; Bramesfeld, Anke; Stegbauer, Constance</p> <p>2017-09-05</p> <p>Working requirements of <span class="hlt">community</span> mental healthcare professionals in integrated care are complex. There is a lack of research concerning the relation of job satisfaction, working <span class="hlt">atmosphere</span> and individual characteristics. For the current study, a survey evaluating job satisfaction and working <span class="hlt">atmosphere</span> of mental healthcare professionals in integrated care was performed. About 321 <span class="hlt">community</span> mental healthcare professionals were included in the survey; the response rate was 59.5%. The professional background of <span class="hlt">community</span> mental healthcare professionals included nursing, social work and psychology. <span class="hlt">Community</span> mental healthcare professionals reported the highest satisfaction with colleagues and the lowest satisfaction with income. Moreover, it could be shown that more responsibility, more recognition and more variety in job tasks lead to an increase of overall job satisfaction. Healthcare for mentally ill patients in the <span class="hlt">community</span> setting is complex and requires well-structured care with appropriate responsibilities within the team. A co-operative relationship among colleagues as well as clearly defined responsibilities seem to be the key for the job satisfaction of <span class="hlt">community</span> mental healthcare professionals in integrated care. © 2017 John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830023875','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830023875"><span>Comparison of <span class="hlt">modelled</span> and empirical <span class="hlt">atmospheric</span> propagation data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schott, J. R.; Biegel, J. D.</p> <p>1983-01-01</p> <p>The radiometric integrity of TM thermal infrared channel data was evaluated and monitored to develop improved radiometric preprocessing calibration techniques for removal of <span class="hlt">atmospheric</span> effects. <span class="hlt">Modelled</span> <span class="hlt">atmospheric</span> transmittance and path radiance were compared with empirical values derived from aircraft underflight data. Aircraft thermal infrared imagery and calibration data were available on two dates as were corresponding <span class="hlt">atmospheric</span> radiosonde data. The radiosonde data were used as input to the LOWTRAN 5A code which was modified to output <span class="hlt">atmospheric</span> path radiance in addition to transmittance. The aircraft data were calibrated and used to generate analogous measurements. These data indicate that there is a tendancy for the LOWTRAN <span class="hlt">model</span> to underestimate <span class="hlt">atmospheric</span> path radiance and transmittance as compared to empirical data. A plot of transmittance versus altitude for both LOWTRAN and empirical data is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=342295','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=342295"><span>Know your <span class="hlt">community</span>: evapotranspiration measurement and <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>This publication discusses the Evapotranspiration Measurement and <span class="hlt">Modeling</span> <span class="hlt">Community</span> in the Agronomy Society of America. The importance of Evapotranspiration (ET) for agricultural studies is discussed along with research tools and methodologies for measuring and <span class="hlt">modeling</span> ET. We discuss the communi...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/390819','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/390819"><span>JORNEX: An airborne campaign to quantify rangeland vegetation change and plant <span class="hlt">community-atmospheric</span> interactions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ritchie, J.C.; Rango, A.; Kustas, W.P.</p> <p>1996-11-01</p> <p>The Jornada Experimental Range in New Mexico provides a unique opportunity to integrate hydrologic-<span class="hlt">atmospheric</span> fluxes and surface states, vegetation types, cover, and distribution, and vegetation response to changes in hydrologic states and <span class="hlt">atmospheric</span> driving forces. The Jornada Range is the site of a long-term ecological research program to investigate the processes leading to desertification. In concert with ongoing ground measurements, remotely sensed data are being collected from ground, airborne, and satellite platforms during JORNEX (the JORNada Experiment) to provide spatial and temporal distribution of vegetation state using laser altimeter and multispectral aircraft and satellite data and surface energy balance estimates from a combination of parameters and state variables derived from remotely sensed data. These measurements will be used as inputs to <span class="hlt">models</span> to quantify the hydrologic budget and the plant response to changes in components in the water and energy balance. Intensive three day study periods for ground and airborne campaigns have been made in May 1995 (dry season) and September 1995 (wet season), February 1996 (Winter) and are planned for wet and dry seasons of 1996. An airborne platform is being used to collect thermal, multispectral, 3-band video, and laser altimetry profile data. Bowen ratio-energy balance stations were established in shrub and grass <span class="hlt">communities</span> in May 1995 and are collecting data continuously. Additional energy flux measurements were made using eddy correlation techniques during the September 1995 campaign. Ground-based measurements during the intensive campaigns include thermal and multispectral measurements made using yoke-based platforms and hand-held instruments, LAI, and other vegetation data. Ground and aircraft measurements are acquired during Landsat overpasses so the effect of scale on measurements can be studied. This paper discusses preliminary results from the 1995 airborne campaign. 24 refs., 13 figs., 1 tab.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040084667','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040084667"><span>Advancing Solid Earth Science through Improved <span class="hlt">Atmosphere</span> <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Niell, A. E.</p> <p>2004-01-01</p> <p>We proposed to investigate and develop better <span class="hlt">models</span> for the effect of the hydrostatic and water vapor components of the neutral <span class="hlt">atmosphere</span> on delay for VLBI and GPS by using a Numerical Weather <span class="hlt">Model</span> to better simulate realistic <span class="hlt">atmosphere</span> conditions. By using a raytrace calculation through the <span class="hlt">model</span> <span class="hlt">atmosphere</span> at the times of actual VLBI observations, the potential improvement in geodetic results can be evaluated. Also, by calculating the actual variation of delays with elevation and azimuth, the errors in current mapping function <span class="hlt">models</span> can be assessed. The VLBI data to be initially analyzed are the fifteen days of the CONT02 sessions of 2002 October which included eight stations. There are three segments to the research. 1) The PSU/NCAR fifth generation mesoscale numerical weather <span class="hlt">model</span> (MM5) will be used to provide the state of the <span class="hlt">atmosphere</span> with highest horizontal resolution of 3 km. 2) A three-dimensional raytrace program will be developed to determine the delays through the <span class="hlt">model</span> <span class="hlt">atmosphere</span> at the times and in the directions of the VLBI observations for each of the sites. 3) The VLBI data will be analyzed using both standard <span class="hlt">models</span> for the <span class="hlt">atmosphere</span> mapping functions and the mapping functions derived from the NWM raytracing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22092223','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22092223"><span>AN ANALYTIC RADIATIVE-CONVECTIVE <span class="hlt">MODEL</span> FOR PLANETARY <span class="hlt">ATMOSPHERES</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Robinson, Tyler D.; Catling, David C.</p> <p>2012-09-20</p> <p>We present an analytic one-dimensional radiative-convective <span class="hlt">model</span> of the thermal structure of planetary <span class="hlt">atmospheres</span>. Our <span class="hlt">model</span> assumes that thermal radiative transfer is gray and can be represented by the two-stream approximation. <span class="hlt">Model</span> <span class="hlt">atmospheres</span> are assumed to be in hydrostatic equilibrium, with a power-law scaling between the <span class="hlt">atmospheric</span> pressure and the gray thermal optical depth. The convective portions of our <span class="hlt">models</span> are taken to follow adiabats that account for condensation of volatiles through a scaling parameter to the dry adiabat. By combining these assumptions, we produce simple, analytic expressions that allow calculations of the <span class="hlt">atmospheric</span>-pressure-temperature profile, as well as expressions for the profiles of thermal radiative flux and convective flux. We explore the general behaviors of our <span class="hlt">model</span>. These investigations encompass (1) worlds where <span class="hlt">atmospheric</span> attenuation of sunlight is weak, which we show tend to have relatively high radiative-convective boundaries; (2) worlds with some attenuation of sunlight throughout the <span class="hlt">atmosphere</span>, which we show can produce either shallow or deep radiative-convective boundaries, depending on the strength of sunlight attenuation; and (3) strongly irradiated giant planets (including hot Jupiters), where we explore the conditions under which these worlds acquire detached convective regions in their mid-tropospheres. Finally, we validate our <span class="hlt">model</span> and demonstrate its utility through comparisons to the average observed thermal structure of Venus, Jupiter, and Titan, and by comparing computed flux profiles to more complex <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004SPIE.5396..212S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004SPIE.5396..212S"><span><span class="hlt">Model</span> of radiation transfer in <span class="hlt">atmosphere</span>-smoke system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sushkevich, Tamara A.; Strelkov, Sergey A.; Vladimirova, Ekaterina V.; Kulikov, Alexey K.; Maksakova, Svetlana V.</p> <p>2004-02-01</p> <p>A more detailed <span class="hlt">modeling</span> of interactions between the solar radiation and smoke medium and also of mechanisms of radiative transfer between air and smoke media is required. One-dimensional <span class="hlt">models</span> of solar-radiation transfer in the <span class="hlt">atmosphere</span>-smoke system (SAS), i.e. <span class="hlt">atmosphere</span> with admixtures that arose under the effect of large scale fires (forest, peat, industrial) and lead to forming extending smoke screen, are being developed by us on the basis of two approaches. In one <span class="hlt">model</span>, calculations are performed by the iteration method of characteristics ofr a two-medium SAS: underlying layer - smoke screen, upper layer- <span class="hlt">atmosphere</span>. The second <span class="hlt">model</span> uses the optical transfer operator (OTO) to express the SAS radiation through the influence functions (IFs) of the <span class="hlt">atmosphere</span> and smoke.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ascl.soft01009S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ascl.soft01009S"><span>GrayStarServer: Stellar <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> and spectrum synthesis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Short, C. Ian</p> <p>2017-01-01</p> <p>GrayStarServer is a stellar <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> and spectrum synthesis code of pedagogical accuracy that is accessible in any web browser on commonplace computational devices and that runs on a timescale of a few seconds.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150005626&hterms=internship+chemistry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dinternship%2Bchemistry','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150005626&hterms=internship+chemistry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dinternship%2Bchemistry"><span>Revisions to Photochemical Data for Use in <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shutter, Joshua D.; Willacy, Karen; Allen, Mark</p> <p>2012-01-01</p> <p>Solar and stellar flux incident on an <span class="hlt">atmosphere</span> can cause molecules to dissociate into highly reactive species and allows for photochemical processes to play a fundamental role in <span class="hlt">atmospheric</span> chemistry. While <span class="hlt">models</span> have tried to simulate such processes, they are extremely sensitive to photoabsorption cross-sections and quantum yields: two parameters that are important in determining the photodissociation rate, and hence the lifetime, of <span class="hlt">atmospheric</span> compounds. Obtaining high-resolution and current data for these parameters is therefore highly desirable. Due to this, database and literature searches for high-quality cross-sections and quantum yields were performed and compiled for KINETICS, a Caltech/JPL Chemical Transport <span class="hlt">Model</span> that can be used in <span class="hlt">modeling</span> planetary <span class="hlt">atmospheres</span>. Furthermore, photodissociation rates determined by running a Titan 1-D <span class="hlt">model</span> were used to verify the completeness of these latest revisions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989SPIE.1044..206N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989SPIE.1044..206N"><span><span class="hlt">Modeling</span> The <span class="hlt">Atmosphere</span> As An Unguided Optical Communications Channel</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nuber, Raymond M.</p> <p>1989-07-01</p> <p>Due to the increasing number of applications for optical communications, methods such as computer simulation are needed for the performance analysis of these systems. The objective of this paper is to propose a system level <span class="hlt">model</span> for simulating the Earth's <span class="hlt">atmosphere</span> as an unguided optical communications channel. The major degradations in received optical intensity introduced by the <span class="hlt">atmosphere</span> are scintillation, beam spreading, beam wander, and <span class="hlt">atmospheric</span> transmissivity. The <span class="hlt">model</span> presented here considers scintillation and beam wander to impose random fading in the received signal while beam spreading is a constant loss in intensity. <span class="hlt">Atmospheric</span> transmissivity is treated as a filter-like channel transfer function. Relationships for the parameters of the <span class="hlt">model</span> are given in terms of parameters which characterize the optical link. Also included is a description of an implementation of the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000099712','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000099712"><span>Basic <span class="hlt">Modeling</span> of the Solar <span class="hlt">Atmosphere</span> and Spectrum</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Avrett, Eugene H.; Wagner, William J. (Technical Monitor)</p> <p>2000-01-01</p> <p>During the last three years we have continued the development of extensive computer programs for constructing realistic <span class="hlt">models</span> of the solar <span class="hlt">atmosphere</span> and for calculating detailed spectra to use in the interpretation of solar observations. This research involves two major interrelated efforts: work by Avrett and Loeser on the Pandora computer program for optically thick non-LTE <span class="hlt">modeling</span> of the solar <span class="hlt">atmosphere</span> including a wide range of physical processes, and work by Kurucz on the detailed high-resolution synthesis of the solar spectrum using data for over 58 million atomic and molecular lines. Our objective is to construct <span class="hlt">atmospheric</span> <span class="hlt">models</span> from which the calculated spectra agree as well as possible with high-and low-resolution observations over a wide wavelength range. Such <span class="hlt">modeling</span> leads to an improved understanding of the physical processes responsible for the structure and behavior of the <span class="hlt">atmosphere</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017LPICo2022.8043J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017LPICo2022.8043J"><span>Venus Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Status and Planned Updates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Justh, H. L.; Dwyer Cianciolo, A. M.</p> <p>2017-05-01</p> <p>Details the current status of Venus Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (Venus-GRAM). Provides new sources of data and upgrades that need to be incorporated to maintain credibility and identifies options and features that could increase capability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A34E..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A34E..08S"><span><span class="hlt">Atmospheric</span> Rivers in a Hierarchy of High-Resolution Global <span class="hlt">Atmospheric</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schiemann, R.; Demory, M. E.; Lavers, D. A.; Mizielinski, M.; Vidale, P. L.; Roberts, M.</p> <p>2014-12-01</p> <p><span class="hlt">Atmospheric</span> rivers are long and narrow plumes that carry moisture over land along frontal zones associated with mid-latitude storms. They can account for 90% of the horizontal moisture transport in a given day and are responsible for major flooding, particularly along western coastal regions (western coasts of North America and Europe). It is therefore crucial to well simulate these events in climate <span class="hlt">models</span> in order to improve predictions and attributions of heavy precipitation and flooding along western coastal regions. In this study, we investigate the ability of a state-of-the art climate <span class="hlt">model</span> to represent the location, frequency and structure of <span class="hlt">atmospheric</span> rivers affecting Western Europe and California. By making use of the UPSCALE (UK on PRACE: weather resolving Simulations of Climate for globAL Environmental risk) campaign, a traceable hierarchy of global <span class="hlt">atmospheric</span> simulations (based on the Met Office Unified <span class="hlt">Model</span>, GA3 formulation), with mesh sizes ranging from 130 km to 25 km, we study the impact of improved representation of small-scale processes on the mean climate, its variability and extremes in order to understand the processes underlying observed improvement with higher resolution. Five-member ensembles of 27-year, <span class="hlt">atmosphere</span>-only integrations are available at these resolutions, using both present day forcing and a future climate scenario. Demory et al (2014) have already shown that a relatively coarse resolution limits the <span class="hlt">model</span>'s ability to simulate moisture transport from ocean to land. This is particularly true at mid-latitude, where the transport is dominated by eddies. Increasing horizontal resolution increases eddy transport of moisture at mid-latitudes. Here, we investigate the climatology of <span class="hlt">atmospheric</span> rivers, in particular their frequency and associated precipitation, compared to reanalysis products. Some aspects of the relationship between the improved simulation of moisture transport in current climate conditions, and how this impacts</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22340185','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22340185"><span>ANALYTICAL <span class="hlt">MODELS</span> OF EXOPLANETARY <span class="hlt">ATMOSPHERES</span>. I. <span class="hlt">ATMOSPHERIC</span> DYNAMICS VIA THE SHALLOW WATER SYSTEM</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Heng, Kevin; Workman, Jared E-mail: jworkman@coloradomesa.edu</p> <p>2014-08-01</p> <p>Within the context of exoplanetary <span class="hlt">atmospheres</span>, we present a comprehensive linear analysis of forced, damped, magnetized shallow water systems, exploring the effects of dimensionality, geometry (Cartesian, pseudo-spherical, and spherical), rotation, magnetic tension, and hydrodynamic and magnetic sources of friction. Across a broad range of conditions, we find that the key governing equation for <span class="hlt">atmospheres</span> and quantum harmonic oscillators are identical, even when forcing (stellar irradiation), sources of friction (molecular viscosity, Rayleigh drag, and magnetic drag), and magnetic tension are included. The global <span class="hlt">atmospheric</span> structure is largely controlled by a single key parameter that involves the Rossby and Prandtl numbers. This near-universality breaks down when either molecular viscosity or magnetic drag acts non-uniformly across latitude or a poloidal magnetic field is present, suggesting that these effects will introduce qualitative changes to the familiar chevron-shaped feature witnessed in simulations of <span class="hlt">atmospheric</span> circulation. We also find that hydrodynamic and magnetic sources of friction have dissimilar phase signatures and affect the flow in fundamentally different ways, implying that using Rayleigh drag to mimic magnetic drag is inaccurate. We exhaustively lay down the theoretical formalism (dispersion relations, governing equations, and time-dependent wave solutions) for a broad suite of <span class="hlt">models</span>. In all situations, we derive the steady state of an <span class="hlt">atmosphere</span>, which is relevant to interpreting infrared phase and eclipse maps of exoplanetary <span class="hlt">atmospheres</span>. We elucidate a pinching effect that confines the <span class="hlt">atmospheric</span> structure to be near the equator. Our suite of analytical <span class="hlt">models</span> may be used to develop decisively physical intuition and as a reference point for three-dimensional magnetohydrodynamic simulations of <span class="hlt">atmospheric</span> circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DPS....4721022M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DPS....4721022M"><span>Pluto: <span class="hlt">Modeling</span> of 3-D <span class="hlt">Atmosphere</span>-Surface Interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Michaels, Timothy I.</p> <p>2015-11-01</p> <p><span class="hlt">Atmosphere</span>-surface interactions on Pluto are of great importance to creating and maintaining the <span class="hlt">atmospheric</span> variations and heterogeneous surface that have been observed by New Horizons and two decades' prior work. Publicly released images/data from New Horizons contain numerous fascinating surface features and constrasts. Insights into their origin, maintenance, and/or evolution may be gleaned through multidisciplinary climate <span class="hlt">modeling</span>. Some results from such <span class="hlt">modeling</span> will be presented, with an emphasis on shorter-timescale interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140003184','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140003184"><span>Mars Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> 2010 Version: Users Guide</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justh, H. L.</p> <p>2014-01-01</p> <p>This Technical Memorandum (TM) presents the Mars Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> 2010 (Mars-GRAM 2010) and its new features. Mars-GRAM is an engineering-level <span class="hlt">atmospheric</span> <span class="hlt">model</span> widely used for diverse mission applications. Applications include systems design, performance analysis, and operations planning for aerobraking, entry, descent and landing, and aerocapture. Additionally, this TM includes instructions on obtaining the Mars-GRAM source code and data files as well as running Mars-GRAM. It also contains sample Mars-GRAM input and output files and an example of how to incorporate Mars-GRAM as an <span class="hlt">atmospheric</span> subroutine in a trajectory code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..664C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..664C"><span>A radiative <span class="hlt">model</span> for Titan's <span class="hlt">atmosphere</span> in the IR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cofano, A.; Sindoni, G.</p> <p>2015-10-01</p> <p>The aim of this work is the development of a <span class="hlt">model</span> of Titan <span class="hlt">atmosphere</span> between 1 and 5 micron, using data from Cassini-Huygens mission. The simulations will be useful to remove the <span class="hlt">atmospheric</span> features from the measured spectrum, to study the surface. The radiative transfer <span class="hlt">model</span> is performed with ARS (<span class="hlt">Atmosphere</span> Radiation Spectrum), a a group of Fortran 77 routines, able to calculate absorption coefficients, radiance and other parameters about gas and aerosols at LTE (Local Thermal Equilibrium) [5] and considering multiple scattering in nadir geometry. Our study covers the IR spectral range but it would be extended also to the visible spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A53B0170P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A53B0170P"><span>Reanalyses, <span class="hlt">Models</span> and Measurements in <span class="hlt">Atmospheric</span> Science</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parker, W.</p> <p>2013-12-01</p> <p>Reanalyses, produced via data assimilation, are among the most-used datasets in <span class="hlt">atmospheric</span> science. Because they are a synthesis of traditional observations and computer simulations, however, reanalyses seem importantly different from other 'observational' datasets. I argue that they are less different than one might think. In fact, I suggest that in principle data assimilation can be placed on a spectrum with other measuring and observing activities in <span class="hlt">atmospheric</span> science. In practice, however, most reanalyses are incomplete as observational datasets insofar as they are not accompanied by reliable information about uncertainties. Quantitative uncertainty estimates are out of reach for some fields, but increasingly efforts are being made to assess reanalysis quality. These efforts include comparison with independent observational datasets for particular regions and intercomparison of reanalyses. As with other datasets, users of should be sensitive to the potential limitations of reanalyses, some of which I briefly outline. I emphasize, however, that judgments about the quality of reanalysis fields (and even of individual results within a given field) should be made on a case by case basis; it should not be assumed that fields for which no direct observations were used (so-called 'C' variables) are necessarily untrustworthy, nor should fields for which direct observations were available be used uncritically. The limitations of techniques used to estimate uncertainties in reanalyses, when such estimates are provided, should also be kept in mind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27889141','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27889141"><span>Exploring lot-to-lot variation in spoilage bacterial <span class="hlt">communities</span> on commercial modified <span class="hlt">atmosphere</span> packaged beef.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Säde, Elina; Penttinen, Katri; Björkroth, Johanna; Hultman, Jenni</p> <p>2017-04-01</p> <p>Understanding the factors influencing meat bacterial <span class="hlt">communities</span> is important as these <span class="hlt">communities</span> are largely responsible for meat spoilage. The composition and structure of a bacterial <span class="hlt">community</span> on a high-O2 modified-<span class="hlt">atmosphere</span> packaged beef product were examined after packaging, on the use-by date and two days after, to determine whether the <span class="hlt">communities</span> at each stage were similar to those in samples taken from different production lots. Furthermore, we examined whether the taxa associated with product spoilage were distributed across production lots. Results from 16S rRNA amplicon sequencing showed that while the early samples harbored distinct bacterial <span class="hlt">communities</span>, after 8-12 days storage at 6 °C the <span class="hlt">communities</span> were similar to those in samples from different lots, comprising mainly of common meat spoilage bacteria Carnobacterium spp., Brochothrix spp., Leuconostoc spp. and Lactococcus spp. Interestingly, abundant operational taxonomic units associated with product spoilage were shared between the production lots, suggesting that the bacteria enable to spoil the product were constant contaminants in the production chain. A characteristic succession pattern and the distribution of common spoilage bacteria between lots suggest that both the packaging type and the initial <span class="hlt">community</span> structure influenced the development of the spoilage bacterial <span class="hlt">community</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880008184','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880008184"><span>Development of an engineering <span class="hlt">model</span> <span class="hlt">atmosphere</span> for Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.</p> <p>1988-01-01</p> <p>An engineering <span class="hlt">model</span> <span class="hlt">atmosphere</span> for Mars is being developed with many of the same features and capabilities for the highly successful Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (GRAM) program for Earth's <span class="hlt">atmosphere</span>. As an initial approach, the <span class="hlt">model</span> is being built around the Martian <span class="hlt">atmosphere</span> <span class="hlt">model</span> computer subroutine (ATMOS) of Culp and Stewart (1984). In a longer-term program of research, additional refinements and modifications will be included. ATMOS includes parameterizations to stimulate the effects of solar activity, seasonal variation, diurnal variation magnitude, dust storm effects, and effects due to the orbital position of Mars. One of the current shortcomings of ATMOS is the neglect of surface variation effects. The longer-term period of research and <span class="hlt">model</span> building is to address some of these problem areas and provide further improvements in the <span class="hlt">model</span> (including improved representation of near-surface variations, improved latitude-longitude gradient representation, effects of the large annual variation in surface pressure because of differential condensation/sublimation of the CO2 <span class="hlt">atmosphere</span> in the polar caps, and effects of Martian <span class="hlt">atmospheric</span> wave perturbations on the magnitude of the expected density perturbation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10156991','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10156991"><span>Evaluation protocol for the WIND system <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fast, J.D.</p> <p>1991-12-31</p> <p><span class="hlt">Atmospheric</span> transport and diffusion <span class="hlt">models</span> have been developed for real-time calculations of the location and concentration of toxic or radioactive materials during a accidental release at the Savannah River Site (SRS). These <span class="hlt">models</span> are have been incorporated into an automated menu-driven computer based system called the WIND (Weather INformation and Display) system. In an effort to establish more formal quality assurance procedures for the WIND system <span class="hlt">atmospheric</span> codes, a software evaluation protocol is being developed. An evaluation protocol is necessary to determine how well they may perform in emergency response (real-time) situations. The evaluation of high-impact software must be conducted in accordance with WSRC QA Manual, 1Q, QAP 20-1. This report will describe the method that will be used to evaluate the <span class="hlt">atmospheric</span> <span class="hlt">models</span>. The evaluation will determine the effectiveness of the <span class="hlt">atmospheric</span> <span class="hlt">models</span> in emergency response situations, which is not necessarily the same procedure used for research purposes. The format of the evaluation plan will provide guidance for the evaluation of <span class="hlt">atmospheric</span> <span class="hlt">models</span> that may be added to the WIND system in the future. The evaluation plan is designed to provide the user with information about the WIND system <span class="hlt">atmospheric</span> <span class="hlt">models</span> that is necessary for emergency response situations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/7280066','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/7280066"><span>Evaluation protocol for the WIND system <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Fast, J.D.</p> <p>1991-01-01</p> <p><span class="hlt">Atmospheric</span> transport and diffusion <span class="hlt">models</span> have been developed for real-time calculations of the location and concentration of toxic or radioactive materials during a accidental release at the Savannah River Site (SRS). These <span class="hlt">models</span> are have been incorporated into an automated menu-driven computer based system called the WIND (Weather INformation and Display) system. In an effort to establish more formal quality assurance procedures for the WIND system <span class="hlt">atmospheric</span> codes, a software evaluation protocol is being developed. An evaluation protocol is necessary to determine how well they may perform in emergency response (real-time) situations. The evaluation of high-impact software must be conducted in accordance with WSRC QA Manual, 1Q, QAP 20-1. This report will describe the method that will be used to evaluate the <span class="hlt">atmospheric</span> <span class="hlt">models</span>. The evaluation will determine the effectiveness of the <span class="hlt">atmospheric</span> <span class="hlt">models</span> in emergency response situations, which is not necessarily the same procedure used for research purposes. The format of the evaluation plan will provide guidance for the evaluation of <span class="hlt">atmospheric</span> <span class="hlt">models</span> that may be added to the WIND system in the future. The evaluation plan is designed to provide the user with information about the WIND system <span class="hlt">atmospheric</span> <span class="hlt">models</span> that is necessary for emergency response situations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC53A1022S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC53A1022S"><span>Studying urban land-<span class="hlt">atmospheric</span> interactions by coupling an urban canopy <span class="hlt">model</span> with a single column <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, J.; Wang, Z.</p> <p>2013-12-01</p> <p>Studying urban land-<span class="hlt">atmospheric</span> interactions by coupling an urban canopy <span class="hlt">model</span> with a single column <span class="hlt">atmospheric</span> <span class="hlt">models</span> Jiyun Song and Zhi-Hua Wang School of Sustainable Engineering and the Built Environment, Arizona State University, PO Box 875306, Tempe, AZ 85287-5306 Landuse landcover changes in urban area will modify surface energy budgets, turbulent fluxes as well as dynamic and thermodynamic structures of the overlying <span class="hlt">atmospheric</span> boundary layer (ABL). In order to study urban land-<span class="hlt">atmospheric</span> interactions, we coupled a single column <span class="hlt">atmospheric</span> <span class="hlt">model</span> (SCM) to a cutting-edge single layer urban canopy <span class="hlt">model</span> (SLUCM). Modification of surface parameters such as the fraction of vegetation and engineered pavements, thermal properties of building and pavement materials, and geometrical features of street canyon, etc. in SLUCM dictates the evolution of surface balance of energy, water and momentum. The land surface states then provide lower boundary conditions to the overlying <span class="hlt">atmosphere</span>, which in turn modulates the modification of ABL structure as well as vertical profiles of temperature, humidity, wind speed and tracer gases. The coupled SLUCM-SCM <span class="hlt">model</span> is tested against field measurements of surface layer fluxes as well as profiles of temperature and humidity in the mixed layer under convective conditions. After <span class="hlt">model</span> test, SLUCM-SCM is used to simulate the effect of changing urban land surface conditions on the evolution of ABL structure and dynamics. Simulation results show that despite the prescribed <span class="hlt">atmospheric</span> forcing, land surface states impose significant impact on the physics of the overlying vertical <span class="hlt">atmospheric</span> layer. Overall, this numerical framework provides a useful standalone <span class="hlt">modeling</span> tool to assess the impacts of urban land surface conditions on the local hydrometeorology through land-<span class="hlt">atmospheric</span> interactions. It also has potentially far-reaching implications to urban ecohydrological services for cities under future expansion and climate challenges.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AcO....43...80H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AcO....43...80H"><span>Elevated <span class="hlt">atmospheric</span> CO2 alters the arthropod <span class="hlt">community</span> in a forest understory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hamilton, Jason; Zangerl, Arthur R.; Berenbaum, May R.; Sparks, Jed P.; Elich, Lauren; Eisenstein, Alissa; DeLucia, Evan H.</p> <p>2012-08-01</p> <p>The objective of this study was to determine the extent to which overall population sizes and <span class="hlt">community</span> composition of arthropods in a naturally occurring forest understory are altered by elevated CO2. The Free Air Concentration Enrichment (FACE) method was used to fumigate large, replicated plots in the Piedmont region of North Carolina, USA to achieve the CO2 concentration predicted for 2050 (˜580 μl l-1). In addition, the extent to which unrestricted herbivorous arthropods were spatially delimited in their resource acquisition was determined. Stable isotope data for spiders (δ13C and δ15N) were collected in ambient and elevated CO2 plots and analyzed to determine whether their prey species moved among plots. Elevated CO2 had no effect on total arthropod numbers but had a large effect on the composition of the arthropod <span class="hlt">community</span>. Insects collected in our samples were identified to a level that allowed for an assignment of trophic classification (generally to family). For the groups of insects sensitive to <span class="hlt">atmospheric</span> gas composition, there was an increase in the numbers of individuals collected in primarily predaceous orders (Araneae and Hymenoptera; from 60% to more than 150%) under elevated CO2 and a decrease in the numbers in primarily herbivorous orders (Lepidoptera and Coleoptera; from -30 to -45%). Isotopic data gave no indication that the treatment plots represented a "boundary" to the movement of insects or that there were distinct and independent insect populations inside and outside the treatment plots. A simple two-ended mixing <span class="hlt">model</span> estimates 55% of the carbon and nitrogen in spider biomass originated external to the elevated CO2 plots. In addition to changes in insect performance, decreases in herbivorous arthropods and increases in predaceous arthropods may also be factors involved in reduced herbivory under elevated CO2 in this forest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACPD...1530857F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACPD...1530857F"><span>PCBs in the Arctic <span class="hlt">atmosphere</span>: determining important driving forces using a global <span class="hlt">atmospheric</span> transport <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Friedman, C. L.; Selin, N. E.</p> <p>2015-11-01</p> <p>We present a spatially and temporally resolved global <span class="hlt">atmospheric</span> PCB <span class="hlt">model</span>, driven by meteorological data, that is skilled at simulating mean <span class="hlt">atmospheric</span> PCB concentrations and seasonal cycles in the Northern Hemisphere mid-latitudes, and mean Arctic concentrations. However, the <span class="hlt">model</span> does not capture the observed Arctic summer maximum in <span class="hlt">atmospheric</span> PCBs. We use the <span class="hlt">model</span> to estimate global budgets for the International Council for the Exploration of the Sea 7 PCBs, and demonstrate that congeners that deposit more readily show lower potential for long-range transport, consistent with a recently-described "differential removal hypothesis" regarding the hemispheric transport of PCBs. Using sensitivity simulations to assess processes within, outside, or transport to the Arctic, we examine the influence of climate- and emissions-driven processes on Arctic concentrations and their effect on improving the simulated Arctic seasonal cycle. We find evidence that processes occurring outside the Arctic have a greater influence on Arctic <span class="hlt">atmospheric</span> PCB levels than processes that occur within the Arctic. Our simulations suggest that re-emissions from sea ice melting or from the Arctic Ocean during summer would have to be unrealistically high in order to capture observed temporal trends of PCBs in the Arctic <span class="hlt">atmosphere</span>. We conclude that mid-latitude processes are likely to have a greater effect on the Arctic under global change scenarios than re-emissions within the Arctic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=167005&keyword=Balances&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78827944&CFTOKEN=75617281','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=167005&keyword=Balances&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78827944&CFTOKEN=75617281"><span>INTERCOMPARISON STUDY OF <span class="hlt">ATMOSPHERIC</span> MERCURY <span class="hlt">MODELS</span>: 2. <span class="hlt">MODELING</span> RESULTS VS. LONG-TERM OBSERVATIONS AND COMPARISON OF COUNTRY <span class="hlt">ATMOSPHERIC</span> BALANCES</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Five regional scale <span class="hlt">models</span> with a horizontal domain covering the European continent and its surrounding seas, two hemispheric and one global scale <span class="hlt">model</span> participated in the <span class="hlt">atmospheric</span> Hg <span class="hlt">modelling</span> intercomparison study. The <span class="hlt">models</span> were compared between each other and with availa...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=167005&keyword=Balances&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=167005&keyword=Balances&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>INTERCOMPARISON STUDY OF <span class="hlt">ATMOSPHERIC</span> MERCURY <span class="hlt">MODELS</span>: 2. <span class="hlt">MODELING</span> RESULTS VS. LONG-TERM OBSERVATIONS AND COMPARISON OF COUNTRY <span class="hlt">ATMOSPHERIC</span> BALANCES</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Five regional scale <span class="hlt">models</span> with a horizontal domain covering the European continent and its surrounding seas, two hemispheric and one global scale <span class="hlt">model</span> participated in the <span class="hlt">atmospheric</span> Hg <span class="hlt">modelling</span> intercomparison study. The <span class="hlt">models</span> were compared between each other and with availa...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2251559C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2251559C"><span>Queensborough <span class="hlt">Community</span> College of the City University of New York (CUNY) Solar and <span class="hlt">Atmospheric</span> Research and Education Program</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chantale Damas, M.</p> <p>2015-08-01</p> <p>The Queensborough <span class="hlt">Community</span> College (QCC) of the City University of New York (CUNY), a Hispanic and minority-serving institution, is the recipient of a 2-year NSF EAGER (Early Concept Grants for Exploratory Research) grant to design and implement a high-impact practice integrated research and education program in solar, geospace and <span class="hlt">atmospheric</span> physics. Proposed is a year-long research experience with two components: 1) during the academic year, students are enrolled in a course-based introductory research (CURE) where they conduct research on real-world problems; and 2) during the summer, students are placed in research internships at partner institutions. Specific objectives include: 1) provide QCC students with research opportunities in solar and <span class="hlt">atmospheric</span> physics as early as their first year; 2) develop educational materials in solar and <span class="hlt">atmospheric</span> physics; 3) increase the number of students, especially underrepresented minorities, that transfer to 4-year STEM programs. A modular, interdisciplinary concept approach is used to integrate educational materials into the research experience. The project also uses evidence-based best practices (i.e., Research experience, Mentoring, Outreach, Recruitment, Enrichment and Partnership with 4-year colleges and institutions) that have proven successful at increasing the retention, transfer and graduation rates of <span class="hlt">community</span> college students. Through a strong collaboration with CUNY’s 4-year colleges (Medgar Evers College and the City College of New York’s NOAA CREST program); Colorado Center for Astrodynamics Research (CCAR) at the University of Colorado, Boulder; and NASA Goddard Space Flight Center’s <span class="hlt">Community</span> Coordinated <span class="hlt">Modeling</span> Center (CCMC), the project trains and retains underrepresented <span class="hlt">community</span> college students in geosciences-related STEM fields. Preliminary results will be presented at this meeting.*This project is supported by the National Science Foundation Geosciences Directorate under NSF Award</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AdSpR..29.1017Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AdSpR..29.1017Z"><span>Effects of the upper <span class="hlt">atmosphere</span> on terrestrial and space communications: the new cost 271 action of the European scientific <span class="hlt">community</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zolesi, B.; Cander, Lj. R.</p> <p></p> <p>During the last decade important results have been obtained by the two COST Actions (Co-operation in the Field of Scientific and Technical Research) promoted by the European Union: the PRIME (Prediction and Retrospective Ionospheric <span class="hlt">Modelling</span> over Europe) and the IITS (Improved Quality of Service in Ionospheric Telecommunication Systems Planning and Operation). The European scientific <span class="hlt">community</span> involved in the ionospheric physics, radio propagation and space science has then proposed a new 4 years Action on the effects of the upper <span class="hlt">atmosphere</span> on terrestrial and Earth space communications. The objectives and the most important directions of this recently accepted COST271 project are here shortly outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.H33F1386S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H33F1386S"><span>Coupling groundwater, vegetation and <span class="hlt">atmosphere</span> processes: a comparison of two integrated <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sulis, M.; Williams, J. L.; Shrestha, P.; Maxwell, R. M.; Masbou, M.; Simmer, C.</p> <p>2012-12-01</p> <p>The correct <span class="hlt">modelling</span> of the mutual response to and feedback between <span class="hlt">atmospheric</span>, hydrological, and ecological processes is an important prerequisite for accurate climate/meteorological projection, environmental protection, and water management. As such, numerical <span class="hlt">models</span> based on a detailed representation of both groundwater and <span class="hlt">atmospheric</span> dynamics have gained increasing attention within the scientific <span class="hlt">community</span>. In this study, we compare two integrated systems that dynamically simulate soil-vegetation-<span class="hlt">atmosphere</span> interactions. One system is the combination of the Weather Research and Forecasting (WRF) <span class="hlt">atmospheric</span> <span class="hlt">model</span> coupled with the three-dimensional variably saturated subsurface ParFlow <span class="hlt">model</span>. Both sub-<span class="hlt">models</span> are internally coupled in an explicit, operator-splitting manner via the Noah land surface scheme. The second system consists of the regional climate and weather forecast <span class="hlt">model</span> COSMO coupled also with ParFlow but via the <span class="hlt">Community</span> Land <span class="hlt">Model</span> (CLM). In this second system the external OASIS coupler is used to pass relevant fluxes and state variables between these three components via the MPI parallel communications protocol. The comparison on how interactions are simulated and how different processes are integrated/coupled is carried out by selecting a set of test cases. These tests involve a flat domain with idealized initial and boundary conditions, as well as simulations over the Rur catchment in Germany based upon equilibrium initial conditions for the subsurface and realistic <span class="hlt">atmospheric</span> conditions at the boundaries. We explore and explain the differences in <span class="hlt">model</span> response, and we discuss the pros and cons of the two approaches by emphasizing the role played by factors such as temporal subcycling and coupling frequency between <span class="hlt">model</span> components.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985JGR....9012927M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985JGR....9012927M"><span><span class="hlt">Modeling</span> <span class="hlt">atmospheric</span> transport to the Marshall Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Merrill, John T.; Bleck, Rainer; Avila, Lixion</p> <p>1985-12-01</p> <p>Isentropic trajectory analyses are presented which support the hypothesis that <span class="hlt">atmospheric</span> continental material found at Enewetak Atoll (11.3°N, 162.3°E) during the Sea-Air Exchange (SEAREX) experiments in 1979 had its origin primarily in Asia in the springtime (dry season experiment) and in North and Central America in the summer (wet season experiment). Fields of wind, Montgomery potential, and pressure on isentropic surfaces are obtained from global isobaric analyses by vertical interpolation. Trajectories backward in time from the area at and upwind of the experiment site were calculated using these fields. In April and May 1979 the <span class="hlt">atmospheric</span> chemistry at Enewetak was influenced strongly by long-range transport from Asia; this transport was primarily in the potential temperature range 305-315 K with travel times of 8-13 days. Westerly winds over Asia at 350-600 mbar carry continental materials over the ocean, and as the air moves southward, subsidence occurs until the air is entrained in the trade wind flow. During July and August 1979 the transport paths were from open ocean areas and from near North and Central America at 305-310 K with travel times of 17-21 days. The trajectories remained at low levels within the boundary layer during this period. Also discussed is a meteorological analysis of dust storms in China, which shows that a mechanism exists for lifting eolian material to the upper troposphere. There is substantial uncertainty in the individual trajectories, and the factors limiting their accuracy are discussed. Given the consistency of the trajectory analyses with the chemical results, we now have a coherent picture of some of the processes responsible for long-range transport to the subtropical open ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/934686','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/934686"><span><span class="hlt">Atmospheric</span> Dispersion <span class="hlt">Model</span> Validation in Low Wind Conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sawyer, Patrick</p> <p>2007-11-01</p> <p><span class="hlt">Atmospheric</span> plume dispersion <span class="hlt">models</span> are used for a variety of purposes including emergency planning and response to hazardous material releases, determining force protection actions in the event of a Weapons of Mass Destruction (WMD) attack and for locating sources of pollution. This study provides a review of previous studies that examine the accuracy of <span class="hlt">atmospheric</span> plume dispersion <span class="hlt">models</span> for chemical releases. It considers the principles used to derive air dispersion plume <span class="hlt">models</span> and looks at three specific <span class="hlt">models</span> currently in use: Aerial Location of Hazardous <span class="hlt">Atmospheres</span> (ALOHA), Emergency Prediction Information Code (EPIcode) and Second Order Closure Integrated Puff (SCIPUFF). Results from this study indicate over-prediction bias by the EPIcode and SCIPUFF <span class="hlt">models</span> and under-prediction bias by the ALOHA <span class="hlt">model</span>. The experiment parameters were for near field dispersion (less than 100 meters) in low wind speed conditions (less than 2 meters per second).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007IzAOP..43..413F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007IzAOP..43..413F"><span>Statistical analysis of a global photochemical <span class="hlt">model</span> of the <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frol'Kis, V. A.; Karol', I. L.; Kiselev, A. A.; Ozolin, Yu. E.; Zubov, V. A.</p> <p>2007-08-01</p> <p>This is a study of the sensitivity of <span class="hlt">model</span> results (<span class="hlt">atmospheric</span> content of main gas constituents and radiative characteristics of the <span class="hlt">atmosphere</span>) to errors in emissions of a number of <span class="hlt">atmospheric</span> gaseous pollutants. Groups of the <span class="hlt">model</span> variables most dependent on these errors are selected. Two variants of emissions are considered: one without their evolution and the other with their variation according to the IPCC scenario. The estimates are made on the basis of standard statistical methods for the results obtained with the detailed onedimensional radiative—photochemical <span class="hlt">model</span> of the Main Geophysical Observatory (MGO). Some approaches to such estimations with <span class="hlt">models</span> of higher complexity and to the solution of the inverse problem (i.e., the estimation of the necessary accuracy of external <span class="hlt">model</span> parameters for obtaining the given accuracy of <span class="hlt">model</span> results) are outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/scram','PESTICIDES'); return false;" href="https://www.epa.gov/scram"><span>Support Center for Regulatory <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> (SCRAM)</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>This technical site provides access to air quality <span class="hlt">models</span> (including computer code, input data, and <span class="hlt">model</span> processors) and other mathematical simulation techniques used in assessing air emissions control strategies and source impacts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EPJA...52...20S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EPJA...52...20S"><span>Measuring the basic parameters of neutron stars using <span class="hlt">model</span> <span class="hlt">atmospheres</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Suleimanov, V. F.; Poutanen, J.; Klochkov, D.; Werner, K.</p> <p>2016-02-01</p> <p><span class="hlt">Model</span> spectra of neutron star <span class="hlt">atmospheres</span> are nowadays widely used to fit the observed thermal X-ray spectra of neutron stars. This fitting is the key element in the method of the neutron star radius determination. Here, we present the basic assumptions used for the neutron star <span class="hlt">atmosphere</span> <span class="hlt">modeling</span> as well as the main qualitative features of the stellar <span class="hlt">atmospheres</span> leading to the deviations of the emergent <span class="hlt">model</span> spectrum from blackbody. We describe the properties of two of our <span class="hlt">model</span> <span class="hlt">atmosphere</span> grids: i) pure carbon <span class="hlt">atmospheres</span> for relatively cool neutron stars (1-4MK) and ii) hot <span class="hlt">atmospheres</span> with Compton scattering taken into account. The results obtained by applying these grids to <span class="hlt">model</span> the X-ray spectra of the central compact object in supernova remnant HESS 1731-347, and two X-ray bursting neutron stars in low-mass X-ray binaries, 4U 1724-307 and 4U 1608-52, are presented. Possible systematic uncertainties associated with the obtained neutron star radii are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=weather+AND+predictions&pg=5&id=ED540138','ERIC'); return false;" href="https://eric.ed.gov/?q=weather+AND+predictions&pg=5&id=ED540138"><span>Information Flow in an <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> and Data Assimilation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Yoon, Young-noh</p> <p>2011-01-01</p> <p>Weather forecasting consists of two processes, <span class="hlt">model</span> integration and analysis (data assimilation). During the <span class="hlt">model</span> integration, the state estimate produced by the analysis evolves to the next cycle time according to the <span class="hlt">atmospheric</span> <span class="hlt">model</span> to become the background estimate. The analysis then produces a new state estimate by combining the background…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730018598','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730018598"><span><span class="hlt">Models</span> of earth's <span class="hlt">atmosphere</span> (90 to 2500 km)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1973-01-01</p> <p>This monograph replaces a monograph on the upper <span class="hlt">atmosphere</span> which was a computerized version of Jacchia's <span class="hlt">model</span>. The current <span class="hlt">model</span> has a range from 90 to 2500 km. In addition to the computerized <span class="hlt">model</span>, a quick-look prediction method is given that may be used to estimate the density for any time and spatial location without using a computer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Weather+AND+forecasting&id=ED540138','ERIC'); return false;" href="http://eric.ed.gov/?q=Weather+AND+forecasting&id=ED540138"><span>Information Flow in an <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> and Data Assimilation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Yoon, Young-noh</p> <p>2011-01-01</p> <p>Weather forecasting consists of two processes, <span class="hlt">model</span> integration and analysis (data assimilation). During the <span class="hlt">model</span> integration, the state estimate produced by the analysis evolves to the next cycle time according to the <span class="hlt">atmospheric</span> <span class="hlt">model</span> to become the background estimate. The analysis then produces a new state estimate by combining the background…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940019925','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940019925"><span>Session on coupled <span class="hlt">atmospheric</span>/chemistry coupled <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thompson, Anne</p> <p>1993-01-01</p> <p>The session on coupled <span class="hlt">atmospheric</span>/chemistry coupled <span class="hlt">models</span> is reviewed. Current <span class="hlt">model</span> limitations, current issues and critical unknowns, and <span class="hlt">modeling</span> activity are addressed. Specific recommendations and experimental strategies on the following are given: multiscale surface layer - planetary boundary layer - chemical flux measurements; Eulerian budget study; and Langrangian experiment. Nonprecipitating cloud studies, organized convective systems, and aerosols - heterogenous chemistry are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1077547','SCIGOV-DOEDE'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1077547"><span>Plant Response and Environmental Data from the Oldfield <span class="hlt">Community</span> Climate and <span class="hlt">Atmospheric</span> Manipulation (OCCAM) Project</span></a></p> <p><a target="_blank" href="http://www.osti.gov/dataexplorer">DOE Data Explorer</a></p> <p></p> <p></p> <p>The Oldfield <span class="hlt">Community</span> Climate and <span class="hlt">Atmospheric</span> Manipulation (OCCAM) project is a joint effort of ORNL and the University of Tennessee to investigate <span class="hlt">community</span> and ecosystem response to global change, specifically looking at the interactive effects of <span class="hlt">atmospheric</span> carbon dioxide, surface temperatures, and soil moisture. The plants studied for their response to warming temperatures, elevated carbon dioxide, and altered water availability include C3 and C4 grasses, forbs, and legumes. These plants are typical of an old-field ecosystem that establishes itself on unused agricultural land. The results of the research focus on species abundance, production, phenology, and what is going on chemically below ground. Data are currently available from 2003 through July, 2008.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ASPC..448...91A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ASPC..448...91A"><span><span class="hlt">Model</span> <span class="hlt">Atmospheres</span> From Very Low Mass Stars to Brown Dwarfs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allard, F.; Homeier, D.; Freytag, B.</p> <p>2011-12-01</p> <p>Since the discovery of brown dwarfs in 1994, and the discovery of dust cloud formation in the latest Very Low Mass Stars (VLMs) and Brown Dwarfs (BDs) in 1996, the most important challenge in <span class="hlt">modeling</span> their <span class="hlt">atmospheres</span> as become the understanding of cloud formation and advective mixing. For this purpose, we have developed radiation hydrodynamic 2D <span class="hlt">model</span> <span class="hlt">atmosphere</span> simulations to study the formation of forsterite dust in presence of advection, condensation, and sedimentation across the M-L-T VLMs to BDs sequence (Teff = 2800 K to 900 K, Freytag et al. 2010). We discovered the formation of gravity waves as a driving mechanism for the formation of clouds in these <span class="hlt">atmospheres</span>, and derived a rule for the velocity field versus <span class="hlt">atmospheric</span> depth and Teff, which is relatively insensitive to gravity. This rule has been used in the construction of the new <span class="hlt">model</span> <span class="hlt">atmosphere</span> grid, BT-Settl, to determine the micro-turbulence velocity, the diffusion coefficient, and the advective mixing of molecules as a function of depth. This new <span class="hlt">model</span> grid of <span class="hlt">atmospheres</span> and synthetic spectra has been computed for 100,000 K > Teff > 400 K, 5.5 > logg > -0.5, and [M/H]= +0.5 to -1.5, and the reference solar abundances of Asplund et al. (2009). We found that the new solar abundances allow an improved (close to perfect) reproduction of the photometric and spectroscopic VLMs properties, and, for the first time, a smooth transition between stellar and substellar regimes -- unlike the transition between the NextGen <span class="hlt">models</span> from Hauschildt et al. 1999a,b, and the AMES-Dusty <span class="hlt">models</span> from Allard et al. 2001. In the BDs regime, the BT-Settl <span class="hlt">models</span> propose an improved explanation for the M-L-T spectral transition. In this paper, we therefore present the new BT-Settl <span class="hlt">model</span> <span class="hlt">atmosphere</span> grid, which explains the entire transition from the stellar to planetary mass regimes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335637&showcriteria=2&timstype=presentation&datebeginpublishedpresented=03/19/2012&dateendpublishedpresented=03/19/2017&sortby=pubdateyear&','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335637&showcriteria=2&timstype=presentation&datebeginpublishedpresented=03/19/2012&dateendpublishedpresented=03/19/2017&sortby=pubdateyear&"><span><span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">Modeling</span> for ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>The CMAQ <span class="hlt">model</span> is a Eulerian <span class="hlt">model</span> that produces gridded values of <span class="hlt">atmospheric</span> concentration and deposition. Recent updates to the <span class="hlt">model</span> are highlighted that impact estimates of dry and wet deposition of nitrogen, sulfur and base cations. Output from the CMAQ <span class="hlt">model</span> is used in the measurement-<span class="hlt">model</span> fusion method used to create the National <span class="hlt">Atmospheric</span> Program's (NADP) Total Deposition (TDEP) map product. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, decision-support tools, and <span class="hlt">models</span> to be applied to media-specific or receptor-specific problem areas. CED uses <span class="hlt">modeling</span>-based approaches to characterize exposures, evaluate fate and transport, and support environmental diagnostics/forensics with input from multiple data sources. It also develops media- and receptor-specific <span class="hlt">models</span>, process <span class="hlt">models</span>, and decision support tools for use both within and outside of EPA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335637&showcriteria=2&fed_org_id=111&timstype=presentation&datebeginpublishedpresented=03/04/2012&dateendpublishedpresented=03/04/2017&sortby=pubdateyear','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=335637&showcriteria=2&fed_org_id=111&timstype=presentation&datebeginpublishedpresented=03/04/2012&dateendpublishedpresented=03/04/2017&sortby=pubdateyear"><span><span class="hlt">Community</span> Multiscale Air Quality (CMAQ) <span class="hlt">Modeling</span> for ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>The CMAQ <span class="hlt">model</span> is a Eulerian <span class="hlt">model</span> that produces gridded values of <span class="hlt">atmospheric</span> concentration and deposition. Recent updates to the <span class="hlt">model</span> are highlighted that impact estimates of dry and wet deposition of nitrogen, sulfur and base cations. Output from the CMAQ <span class="hlt">model</span> is used in the measurement-<span class="hlt">model</span> fusion method used to create the National <span class="hlt">Atmospheric</span> Program's (NADP) Total Deposition (TDEP) map product. The National Exposure Research Laboratory (NERL) Computational Exposure Division (CED) develops and evaluates data, decision-support tools, and <span class="hlt">models</span> to be applied to media-specific or receptor-specific problem areas. CED uses <span class="hlt">modeling</span>-based approaches to characterize exposures, evaluate fate and transport, and support environmental diagnostics/forensics with input from multiple data sources. It also develops media- and receptor-specific <span class="hlt">models</span>, process <span class="hlt">models</span>, and decision support tools for use both within and outside of EPA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920016171','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920016171"><span>Constructing an advanced software tool for planetary <span class="hlt">atmospheric</span> <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keller, Richard M.; Sims, Michael; Podolak, Ester; Mckay, Christopher</p> <p>1990-01-01</p> <p>Scientific <span class="hlt">model</span> building can be an intensive and painstaking process, often involving the development of large and complex computer programs. Despite the effort involved, scientific <span class="hlt">models</span> cannot be easily distributed and shared with other scientists. In general, implemented scientific <span class="hlt">models</span> are complex, idiosyncratic, and difficult for anyone but the original scientist/programmer to understand. We believe that advanced software techniques can facilitate both the <span class="hlt">model</span> building and <span class="hlt">model</span> sharing process. In this paper, we describe a prototype for a scientific <span class="hlt">modeling</span> software tool that serves as an aid to the scientist in developing and using <span class="hlt">models</span>. This tool includes an interactive intelligent graphical interface, a high level domain specific <span class="hlt">modeling</span> language, a library of physics equations and experimental datasets, and a suite of data display facilities. Our prototype has been developed in the domain of planetary <span class="hlt">atmospheric</span> <span class="hlt">modeling</span>, and is being used to construct <span class="hlt">models</span> of Titan's <span class="hlt">atmosphere</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AAS...22940106S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AAS...22940106S"><span><span class="hlt">Atmosphere</span>-magma ocean <span class="hlt">modeling</span> of GJ 1132 b</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schaefer, Laura; Wordsworth, Robin; Berta-Thompson, Zachory K.; Sasselov, Dimitar</p> <p>2017-01-01</p> <p>GJ 1132 b is a nearby Earth-sized exoplanet transiting an M dwarf, and is amongst the most highly characterizable small exoplanets currently known. Using a coupled <span class="hlt">atmosphere</span>-magma ocean <span class="hlt">model</span>, we determine that GJ 1132 b must have begun with more than 5 wt% initial water in order to still retain a water-based <span class="hlt">atmosphere</span>. We also determine the amount of O2 that can build up in the <span class="hlt">atmosphere</span> as a result of hydrogen dissociation and loss. We find that the magma ocean absorbs at most ~ 10% of the O2 produced, whereas more than 90% is lost to space through hydrodynamic drag. The results of the <span class="hlt">model</span> depend strongly on the initial water abundance and the XUV <span class="hlt">model</span>. The most common outcome for GJ 1132 b from our simulations is a tenuous <span class="hlt">atmosphere</span> dominated by O2, although for very large initial water abundances, <span class="hlt">atmospheres</span> with several thousands of bars of O2 are possible. A substantial steam envelope would indicate either the existence of an earlier H2 envelope or low XUV flux over the system's lifetime. A steam <span class="hlt">atmosphere</span> would also imply the continued existence of a magma ocean on GJ 1132 b. Preliminary <span class="hlt">modeling</span> with the addition of CO2 gas will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A23I..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A23I..08M"><span>Using Existing Arctic <span class="hlt">Atmospheric</span> Mercury Measurements to Refine Global and Regional Scale <span class="hlt">Atmospheric</span> Transport <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moore, C. W.; Dastoor, A.; Steffen, A.; Nghiem, S. V.; Agnan, Y.; Obrist, D.</p> <p>2015-12-01</p> <p>Northern hemisphere background <span class="hlt">atmospheric</span> concentrations of gaseous elemental mercury (GEM) have been declining by up to 25% over the last ten years at some lower latitude sites. However, this decline has ranged from no decline to 9% over 10 years at Arctic long-term measurement sites. Measurements also show a highly dynamic nature of mercury (Hg) species in Arctic air and snow from early spring to the end of summer when biogeochemical transformations peak. Currently, <span class="hlt">models</span> are unable to reproduce this variability accurately. Estimates of Hg accumulation in the Arctic and Arctic Ocean by <span class="hlt">models</span> require a full mechanistic understanding of the multi-phase redox chemistry of Hg in air and snow as well as the role of meteorology in the physicochemical processes of Hg. We will show how findings from ground-based <span class="hlt">atmospheric</span> Hg measurements like those made in spring 2012 during the Bromine, Ozone and Mercury Experiment (BROMEX) near Barrow, Alaska can be used to reduce the discrepancy between measurements and <span class="hlt">model</span> output in the Canadian GEM-MACH-Hg <span class="hlt">model</span>. The <span class="hlt">model</span> is able to reproduce and to explain some of the variability in Arctic Hg measurements but discrepancies still remain. One improvement involves incorporation of new physical mechanisms such as the one we were able to identify during BROMEX. This mechanism, by which <span class="hlt">atmospheric</span> mercury depletion events are abruptly ended via sea ice leads opening and inducing shallow convective mixing that replenishes GEM (and ozone) in the near surface <span class="hlt">atmospheric</span> layer, causing an immediate recovery from the depletion event, is currently lacking in <span class="hlt">models</span>. Future implementation of this physical mechanism will have to incorporate current remote sensing sea ice products but also rely on the development of products that can identify sea ice leads quantitatively. In this way, we can advance the knowledge of the dynamic nature of GEM in the Arctic and the impact of climate change along with new regulations on the overall</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981gfma.book.....S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981gfma.book.....S"><span>Guideline for fluid <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> diffusion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Snyder, W. H.</p> <p>1981-04-01</p> <p>The usefulness of fluid <span class="hlt">models</span> are evaluated from both scientific and engineering viewpoints. Because many detailed decisions must be made during the design and execution of each <span class="hlt">model</span> study, and because the fundamental principles frequency do not provide enough guidance, extensive discussion of the details of the most common types of <span class="hlt">modeling</span> problems are provided. The hardware requirements are also discussed. This guidance is intended to be of use both to scientists and engineering involved in operating fluid <span class="hlt">modeling</span> facilities and to air pollution control officials in evaluating the quality and credibility of the reports from such studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JPhCS.276a2223W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JPhCS.276a2223W"><span>The physical theory and propagation <span class="hlt">model</span> of THz <span class="hlt">atmospheric</span> propagation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, R.; Yao, J. Q.; Xu, D. G.; Wang, J. L.; Wang, P.</p> <p>2011-02-01</p> <p>Terahertz (THz) radiation is extensively applied in diverse fields, such as space communication, Earth environment observation, <span class="hlt">atmosphere</span> science, remote sensing and so on. And the research on propagation features of THz wave in the <span class="hlt">atmosphere</span> becomes more and more important. This paper firstly illuminates the advantages and outlook of THz in space technology. Then it introduces the theoretical framework of THz <span class="hlt">atmospheric</span> propagation, including some fundamental physical concepts and processes. The attenuation effect (especially the absorption of water vapor), the scattering of aerosol particles and the effect of turbulent flow mainly influence THz <span class="hlt">atmosphere</span> propagation. Fundamental physical laws are illuminated as well, such as Lamber-beer law, Mie scattering theory and radiative transfer equation. The last part comprises the demonstration and comparison of THz <span class="hlt">atmosphere</span> propagation <span class="hlt">models</span> like Moliere(V5), SARTre and AMATERASU. The essential problems are the deep analysis of physical mechanism of this process, the construction of <span class="hlt">atmospheric</span> propagation <span class="hlt">model</span> and databases of every kind of material in the <span class="hlt">atmosphere</span>, and the standardization of measurement procedures.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=resisting+AND+change&pg=3&id=EJ599590','ERIC'); return false;" href="https://eric.ed.gov/?q=resisting+AND+change&pg=3&id=EJ599590"><span><span class="hlt">Model</span> for the New Millennium: Preserving <span class="hlt">Community</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rezmierski, Virginia E.</p> <p>1999-01-01</p> <p>Addresses issues surrounding higher education and <span class="hlt">community</span> building in the context of the effect on human behavior of the information technology revolution. Suggests the need for a new <span class="hlt">model</span> which will seek to preserve a <span class="hlt">community</span> that is open, just, disciplined, and caring by refocusing on mission, resisting change for its own sake,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED229062.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED229062.pdf"><span>Small Business Training <span class="hlt">Models</span> for <span class="hlt">Community</span> Growth.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jellison, Holly M., Ed.</p> <p></p> <p>Nine successful <span class="hlt">community</span> college programs for small business management training are described in this report in terms of their college and economic context, purpose, offerings, delivery modes, operating and marketing strategies, <span class="hlt">community</span> outreach, support services, faculty and staff, evaluation, and future directions. The <span class="hlt">model</span> programs are…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840046945&hterms=volcanic+influences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D10%26Ntt%3Dvolcanic%2Binfluences','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840046945&hterms=volcanic+influences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D10%26Ntt%3Dvolcanic%2Binfluences"><span>A zonally symmetric <span class="hlt">model</span> for volcanic influence upon <span class="hlt">atmospheric</span> circulation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schatten, K. H.; Mayr, H. G.; Harris, I.; Taylor, H. A., Jr.</p> <p>1984-01-01</p> <p>The effects of volcanic activity upon zonal wind flow in a <span class="hlt">model</span> <span class="hlt">atmosphere</span> are considered. A low latitude volcanic eruption could lower the tropospheric pole to equator temperature difference and thereby affect the <span class="hlt">atmospheric</span> motions. When the temperature contrast decreases, the zonal wind velocities at high altitudes are reduced. To conserve angular momentum, the velocities in the lower <span class="hlt">atmosphere</span> near the surface must increase, thus providing a momentum source for ocean currents. It is suggested that this momentum source may have played a role as a trigger for inducing the 1982-83 anomalous El Nino and possibly other climate changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984GeoRL..11..303S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984GeoRL..11..303S"><span>A zonally symmetric <span class="hlt">model</span> for volcanic influence upon <span class="hlt">atmospheric</span> circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schatten, K. H.; Mayr, H. G.; Harris, I.; Taylor, H. A., Jr.</p> <p>1984-04-01</p> <p>The effects of volcanic activity upon zonal wind flow in a <span class="hlt">model</span> <span class="hlt">atmosphere</span> are considered. A low latitude volcanic eruption could lower the tropospheric pole to equator temperature difference and thereby affect the <span class="hlt">atmospheric</span> motions. When the temperature contrast decreases, the zonal wind velocities at high altitudes are reduced. To conserve angular momentum, the velocities in the lower <span class="hlt">atmosphere</span> near the surface must increase, thus providing a momentum source for ocean currents. It is suggested that this momentum source may have played a role as a trigger for inducing the 1982-83 anomalous El Nino and possibly other climate changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=Fowler&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DFowler%252C%2BR.%2BT.%2BJ.','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=Fowler&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DFowler%252C%2BR.%2BT.%2BJ."><span>Cloud Feedback in <span class="hlt">Atmospheric</span> General Circulation <span class="hlt">Models</span>: An Update</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cess, R. D.; Zhang, M. H.; Ingram, W. J.; Potter, G. L.; Alekseev, V.; Barker, H. W.; Cohen-Solal, E.; Colman, R. A.; Dazlich, D. A.; DelGenio, A. D.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_19990111731'); toggleEditAbsImage('author_19990111731_show'); toggleEditAbsImage('author_19990111731_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_19990111731_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_19990111731_hide"></p> <p>1996-01-01</p> <p>Six years ago, we compared the climate sensitivity of 19 <span class="hlt">atmospheric</span> general circulation <span class="hlt">models</span> and found a roughly threefold variation among the <span class="hlt">models</span>; most of this variation was attributed to differences in the <span class="hlt">models</span>' depictions of cloud feedback. In an update of this comparison, current <span class="hlt">models</span> showed considerably smaller differences in net cloud feedback, with most producing modest values. There are, however, substantial differences in the feedback components, indicating that the <span class="hlt">models</span> still have physical disagreements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=hack&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dhack','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=hack&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dhack"><span>Cloud Feedback in <span class="hlt">Atmospheric</span> General Circulation <span class="hlt">Models</span>: An Update</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cess, R. D.; Zhang, M. H.; Ingram, W. J.; Potter, G. L.; Alekseev, V.; Barker, H. W.; Cohen-Solal, E.; Colman, R. A.; Dazlich, D. A.; DelGenio, A. D.; Dix, M. R.; Dymnikov, V.; Esch, M.; Fowler, L. D.; Fraser, J. R.; Galin, V.; Gates, W. L.; Hack, J. J.; Kiehl, J. T.; LeTreut, H.</p> <p>1996-01-01</p> <p>Six years ago, we compared the climate sensitivity of 19 <span class="hlt">atmospheric</span> general circulation <span class="hlt">models</span> and found a roughly threefold variation among the <span class="hlt">models</span>; most of this variation was attributed to differences in the <span class="hlt">models</span>' depictions of cloud feedback. In an update of this comparison, current <span class="hlt">models</span> showed considerably smaller differences in net cloud feedback, with most producing modest values. There are, however, substantial differences in the feedback components, indicating that the <span class="hlt">models</span> still have physical disagreements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/145245','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/145245"><span>Regional forecasting with global <span class="hlt">atmospheric</span> <span class="hlt">models</span>; Fourth year report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Crowley, T.J.; North, G.R.; Smith, N.R.</p> <p>1994-05-01</p> <p>The scope of the report is to present the results of the fourth year`s work on the <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> part of the global climate studies task. The development testing of computer <span class="hlt">models</span> and initial results are discussed. The appendices contain studies that provide supporting information and guidance to the <span class="hlt">modeling</span> work and further details on computer <span class="hlt">model</span> development. Complete documentation of the <span class="hlt">models</span>, including user information, will be prepared under separate reports and manuals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/755641','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/755641"><span>Peformance Tuning and Evaluation of a Parallel <span class="hlt">Community</span> Climate <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Drake, J.B.; Worley, P.H.; Hammond, S.</p> <p>1999-11-13</p> <p>The Parallel <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (PCCM) is a message-passing parallelization of version 2.1 of the <span class="hlt">Community</span> Climate <span class="hlt">Model</span> (CCM) developed by researchers at Argonne and Oak Ridge National Laboratories and at the National Center for <span class="hlt">Atmospheric</span> Research in the early to mid 1990s. In preparation for use in the Department of Energy's Parallel Climate <span class="hlt">Model</span> (PCM), PCCM has recently been updated with new physics routines from version 3.2 of the CCM, improvements to the parallel implementation, and ports to the SGIKray Research T3E and Origin 2000. We describe our experience in porting and tuning PCCM on these new platforms, evaluating the performance of different parallel algorithm options and comparing performance between the T3E and Origin 2000.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150015485','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150015485"><span><span class="hlt">Atmospheric</span> Turbulence <span class="hlt">Modeling</span> for Aero Vehicles: Fractional Order Fits</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kopasakis, George</p> <p>2015-01-01</p> <p><span class="hlt">Atmospheric</span> turbulence <span class="hlt">models</span> are necessary for the design of both inlet/engine and flight controls, as well as for studying coupling between the propulsion and the vehicle structural dynamics for supersonic vehicles. <span class="hlt">Models</span> based on the Kolmogorov spectrum have been previously utilized to <span class="hlt">model</span> <span class="hlt">atmospheric</span> turbulence. In this paper, a more accurate <span class="hlt">model</span> is developed in its representative fractional order form, typical of <span class="hlt">atmospheric</span> disturbances. This is accomplished by first scaling the Kolmogorov spectral to convert them into finite energy von Karman forms and then by deriving an explicit fractional circuit-filter type analog for this <span class="hlt">model</span>. This circuit <span class="hlt">model</span> is utilized to develop a generalized formulation in frequency domain to approximate the fractional order with the products of first order transfer functions, which enables accurate time domain simulations. The objective of this work is as follows. Given the parameters describing the conditions of <span class="hlt">atmospheric</span> disturbances, and utilizing the derived formulations, directly compute the transfer function poles and zeros describing these disturbances for acoustic velocity, temperature, pressure, and density. Time domain simulations of representative <span class="hlt">atmospheric</span> turbulence can then be developed by utilizing these computed transfer functions together with the disturbance frequencies of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110002734','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110002734"><span><span class="hlt">Atmospheric</span> Turbulence <span class="hlt">Modeling</span> for Aero Vehicles: Fractional Order Fits</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kopasakis, George</p> <p>2010-01-01</p> <p><span class="hlt">Atmospheric</span> turbulence <span class="hlt">models</span> are necessary for the design of both inlet/engine and flight controls, as well as for studying coupling between the propulsion and the vehicle structural dynamics for supersonic vehicles. <span class="hlt">Models</span> based on the Kolmogorov spectrum have been previously utilized to <span class="hlt">model</span> <span class="hlt">atmospheric</span> turbulence. In this paper, a more accurate <span class="hlt">model</span> is developed in its representative fractional order form, typical of <span class="hlt">atmospheric</span> disturbances. This is accomplished by first scaling the Kolmogorov spectral to convert them into finite energy von Karman forms and then by deriving an explicit fractional circuit-filter type analog for this <span class="hlt">model</span>. This circuit <span class="hlt">model</span> is utilized to develop a generalized formulation in frequency domain to approximate the fractional order with the products of first order transfer functions, which enables accurate time domain simulations. The objective of this work is as follows. Given the parameters describing the conditions of <span class="hlt">atmospheric</span> disturbances, and utilizing the derived formulations, directly compute the transfer function poles and zeros describing these disturbances for acoustic velocity, temperature, pressure, and density. Time domain simulations of representative <span class="hlt">atmospheric</span> turbulence can then be developed by utilizing these computed transfer functions together with the disturbance frequencies of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150003441','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150003441"><span><span class="hlt">Atmospheric</span> Turbulence <span class="hlt">Modeling</span> for Aerospace Vehicles: Fractional Order Fit</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kopasakis, George (Inventor)</p> <p>2015-01-01</p> <p>An improved <span class="hlt">model</span> for simulating <span class="hlt">atmospheric</span> disturbances is disclosed. A scale Kolmogorov spectral may be scaled to convert the Kolmogorov spectral into a finite energy von Karman spectral and a fractional order pole-zero transfer function (TF) may be derived from the von Karman spectral. Fractional order <span class="hlt">atmospheric</span> turbulence may be approximated with an integer order pole-zero TF fit, and the approximation may be stored in memory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1227980','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1227980"><span>Development of hybrid 3-D hydrological <span class="hlt">modeling</span> for the NCAR <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zeng, Xubin; Troch, Peter; Pelletier, Jon; Niu, Guo-Yue; Gochis, David</p> <p>2015-11-15</p> <p>This is the Final Report of our four-year (3-year plus one-year no cost extension) collaborative project between the University of Arizona (UA) and the National Center for <span class="hlt">Atmospheric</span> Research (NCAR). The overall objective of our project is to develop and evaluate the first hybrid 3-D hydrological <span class="hlt">model</span> with a horizontal grid spacing of 1 km for the NCAR <span class="hlt">Community</span> Earth System <span class="hlt">Model</span> (CESM).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC43F..05W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC43F..05W"><span>The Role of <span class="hlt">Atmospheric</span> Measurements in Wind Power Statistical <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wharton, S.; Bulaevskaya, V.; Irons, Z.; Newman, J. F.; Clifton, A.</p> <p>2015-12-01</p> <p>The simplest wind power generation curves <span class="hlt">model</span> power only as a function of the wind speed at turbine hub-height. While the latter is an essential predictor of power output, it is widely accepted that wind speed information in other parts of the vertical profile, as well as additional <span class="hlt">atmospheric</span> variables including <span class="hlt">atmospheric</span> stability, wind veer, and hub-height turbulence are also important factors. The goal of this work is to determine the gain in predictive ability afforded by adding additional <span class="hlt">atmospheric</span> measurements to the power prediction <span class="hlt">model</span>. In particular, we are interested in quantifying any gain in predictive ability afforded by measurements taken from a laser detection and ranging (lidar) instrument, as lidar provides high spatial and temporal resolution measurements of wind speed and direction at 10 or more levels throughout the rotor-disk and at heights well above. Co-located lidar and meteorological tower data as well as SCADA power data from a wind farm in Northern Oklahoma will be used to train a set of statistical <span class="hlt">models</span>. In practice, most wind farms continue to rely on <span class="hlt">atmospheric</span> measurements taken from less expensive, in situ instruments mounted on meteorological towers to assess turbine power response to a changing <span class="hlt">atmospheric</span> environment. Here, we compare a large suite of <span class="hlt">atmospheric</span> variables derived from tower measurements to those taken from lidar to determine if remote sensing devices add any competitive advantage over tower measurements alone to predict turbine power response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/422950','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/422950"><span>Operational evaluation of forecast and diagnostic <span class="hlt">atmospheric</span> <span class="hlt">models</span> in a forest canopy environment</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Atchison, M.K.; Dean, D.; Lambert, W.C.; Seely, S.</p> <p>1996-12-31</p> <p>For many years, simple Gaussian diffusion <span class="hlt">models</span> have been used by the operational <span class="hlt">community</span> for real-time air pollution analysis. These <span class="hlt">models</span> generally produce quick, reasonable results for short distances and simple meteorological situations. However <span class="hlt">model</span> simulations involving complex topography or weather patterns may produce very unreliable results. In order to aid the user in <span class="hlt">model</span> selection, a study is currently underway to evaluate several mesoscale and trajectory-diffusion type <span class="hlt">models</span> for source to sampler distances of up to 150 km in various environments. The <span class="hlt">models</span> chosen for this study are the Regional <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> System (RAMS), the Higher Order Turbulence <span class="hlt">Model</span> for <span class="hlt">Atmospheric</span> Circulation (HOTMAC) and the Short-Range Layered <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> (SLAM). RAMS and HOTMAC are traditional meteorological forecast <span class="hlt">models</span> while SLAM is a diagnostic trajectory and diffusion <span class="hlt">model</span>. These <span class="hlt">models</span> are undergoing an evaluation using ground-based tracer data from meteorological experiments representing desert, forest, complex topography, and lands/sea breeze physiographic environments. The focus of the present work will be in the forest canopy environment using data from the Short Range Experiment (SRE) conducted at the Savannah River Plant from March 1975 through September 1977.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910042403&hterms=Shukla&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DShukla','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910042403&hterms=Shukla&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DShukla"><span>Predictability of a coupled ocean-<span class="hlt">atmosphere</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goswami, B. N.; Shukla, J.</p> <p>1991-01-01</p> <p>A study is presented to determine the limits on the predictability of the coupled ocean-<span class="hlt">atmosphere</span> system. Following the classical methods developed for <span class="hlt">atmospheric</span> predictability studies, the <span class="hlt">model</span> used is one of the simplest that realistically reproduces many of the important features of the observed interannual variability of sea surface temperature in the tropical Pacific Ocean when forced by observed wind stresses. As no reasonable analysis is available for all the fields, initial conditions for these prediction experiments were taken from a <span class="hlt">model</span> control run in which the ocean <span class="hlt">model</span> was forced by the observed surface winds. The <span class="hlt">atmospheric</span> component of the coupled <span class="hlt">model</span> is not capable of accurately simulating the large-scale components of the observed wind stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...826..225M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...826..225M"><span>Examining Tatooine: <span class="hlt">Atmospheric</span> <span class="hlt">Models</span> of Neptune-like Circumbinary Planets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>May, E. M.; Rauscher, E.</p> <p>2016-08-01</p> <p>Circumbinary planets experience a time-varying irradiation pattern as they orbit their two host stars. In this work, we present the first detailed study of the <span class="hlt">atmospheric</span> effects of this irradiation pattern on known and hypothetical gaseous circumbinary planets. Using both a one-dimensional energy balance <span class="hlt">model</span> (EBM) and a three-dimensional general circulation <span class="hlt">model</span> (GCM), we look at the temperature differences between circumbinary planets and their equivalent single-star cases in order to determine the nature of the <span class="hlt">atmospheres</span> of these planets. We find that for circumbinary planets on stable orbits around their host stars, temperature differences are on average no more than 1.0% in the most extreme cases. Based on detailed <span class="hlt">modeling</span> with the GCM, we find that these temperature differences are not large enough to excite circulation differences between the two cases. We conclude that gaseous circumbinary planets can be treated as their equivalent single-star case in future <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850005880&hterms=biosphere+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dbiosphere%2Bmodeling','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850005880&hterms=biosphere+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dbiosphere%2Bmodeling"><span>Three dimensional global <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> CO2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hanse, J.; Fung, I.; Rind, D.</p> <p>1984-01-01</p> <p>The initial attempts to <span class="hlt">model</span> the <span class="hlt">atmospheric</span> CO2 distribution, including couplings to the ocean and biosphere as sources and sinks of <span class="hlt">atmospheric</span> CO2, encourage the notion that this approach will lead to useful quantitative constraints on CO2 fluxes. Realization of this objective will require: (1) continued improvement in the realism of the global transport <span class="hlt">modeling</span>; (2) extended timeline of <span class="hlt">atmospheric</span> CO2 monitoring, which improved precision and improved definition of the uncertainties in the measured CO2 amounts; and (3) given an accurate knowledge of <span class="hlt">model</span> capabilities and limitations and given a good understanding of CO2 observations and their limitations, there is a need for good ideas concerning what quantitative information on the carbon cycle can be inferred from global <span class="hlt">modeling</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850005880&hterms=fossil+fuels+timeline&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dfossil%2Bfuels%2Btimeline','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850005880&hterms=fossil+fuels+timeline&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dfossil%2Bfuels%2Btimeline"><span>Three dimensional global <span class="hlt">modeling</span> of <span class="hlt">atmospheric</span> CO2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hanse, J.; Fung, I.; Rind, D.</p> <p>1984-01-01</p> <p>The initial attempts to <span class="hlt">model</span> the <span class="hlt">atmospheric</span> CO2 distribution, including couplings to the ocean and biosphere as sources and sinks of <span class="hlt">atmospheric</span> CO2, encourage the notion that this approach will lead to useful quantitative constraints on CO2 fluxes. Realization of this objective will require: (1) continued improvement in the realism of the global transport <span class="hlt">modeling</span>; (2) extended timeline of <span class="hlt">atmospheric</span> CO2 monitoring, which improved precision and improved definition of the uncertainties in the measured CO2 amounts; and (3) given an accurate knowledge of <span class="hlt">model</span> capabilities and limitations and given a good understanding of CO2 observations and their limitations, there is a need for good ideas concerning what quantitative information on the carbon cycle can be inferred from global <span class="hlt">modeling</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985AdSpR...5..155K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985AdSpR...5..155K"><span>Proposed ozone reference <span class="hlt">models</span> for the middle <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keating, G. M.; Young, D. F.</p> <p></p> <p>Since the publication of the last COSPAR International Reference <span class="hlt">Atmosphere</span> (CIRA 72), large amounts of ozone data acquired from satellites have become available in addition to increasing quantities of rocketsonde, balloonsonde, Dobson, M83, and Umkehr measurements. From the available archived satellite data, <span class="hlt">models</span> are developed for the new CIRA using 5 satellite experiments (Nimbus 7 SBUV and LIMS, AEM-2 SAGE, and SME IR and UVS) of the monthly latitudinal and altitudinal variations in the ozone mixing ratio in the middle <span class="hlt">atmosphere</span>. Standard deviations and interannual variations are also quantified. The satellite <span class="hlt">models</span> are shown to agree well with a previous reference <span class="hlt">model</span> based on rocket and balloon measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030066242&hterms=Neptune&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNeptune','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030066242&hterms=Neptune&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DNeptune"><span>Engineering-Level <span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for Titan & Neptune</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Johnson, D. L.</p> <p>2003-01-01</p> <p>Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for Titan and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications in missions to the outer planets. Analogous to highly successful Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Earth (GRAM, Justus et al., 2000) and Mars (Mars-GRAM, Justus and Johnson, 2001, Justus et al., 2002) the new <span class="hlt">models</span> are called Titan-GRAM and Neptune-GRAM. Like GRAM and Mars-GRAM, an important feature of Titan-GRAM and Neptune-GRAM is their ability to simulate quasi-random perturbations for Monte- Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030066242&hterms=Neptune&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DNeptune','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030066242&hterms=Neptune&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DNeptune"><span>Engineering-Level <span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for Titan & Neptune</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Justus, C. G.; Johnson, D. L.</p> <p>2003-01-01</p> <p>Engineering-level <span class="hlt">atmospheric</span> <span class="hlt">models</span> for Titan and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications in missions to the outer planets. Analogous to highly successful Global Reference <span class="hlt">Atmospheric</span> <span class="hlt">Models</span> for Earth (GRAM, Justus et al., 2000) and Mars (Mars-GRAM, Justus and Johnson, 2001, Justus et al., 2002) the new <span class="hlt">models</span> are called Titan-GRAM and Neptune-GRAM. Like GRAM and Mars-GRAM, an important feature of Titan-GRAM and Neptune-GRAM is their ability to simulate quasi-random perturbations for Monte- Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AAS...22712804H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AAS...22712804H"><span>Forward <span class="hlt">Models</span> of Exoplanets for <span class="hlt">Atmosphere</span> Retrievals with JWST</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howe, Alex; Burrows, Adam Seth</p> <p>2016-01-01</p> <p>We present <span class="hlt">models</span> of extrasolar planets incorporating self-consistent treatment of internal structures, radiative cooling and XUV-driven mass loss over time, and over a range of masses. We also present new <span class="hlt">atmosphere</span> <span class="hlt">models</span> with 1-D radiative transfer and a range of compositions and cloud structures, with both theoretical transit and secondary eclipse spectra. These complimentary <span class="hlt">model</span> sets are designed for performing retrievals of <span class="hlt">atmosphere</span> parameters with data from the upcoming JWST mission. Finally, we present preliminary results with new theoretical spectra fit to well-observed transiting exoplanets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880020882&hterms=simulation+techniques&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsimulation%2Btechniques','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880020882&hterms=simulation+techniques&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsimulation%2Btechniques"><span>A digital simulation technique for the Dryden <span class="hlt">atmospheric</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhao, Zhenyan; Xiao, Yelun; Shi, Yijian</p> <p>1988-01-01</p> <p>The Dryden <span class="hlt">model</span> is usually used in studying the response of flight vehicles to <span class="hlt">atmospheric</span> turbulence. For a modern flight simulator, it is necessary to generate random winds (in Dryden <span class="hlt">model</span> or sometimes others) with a digital computer. A theoretically strict new method to meet this purpose is proposed. By this method, a three dimensional <span class="hlt">atmospheric</span> turbulence can be obtained which contains three components of wind velocity and three components of wind velocity gradient. The reliability of this method is checked by comparing the theoretical autocorrelation value. A numerical example has shown a satisfactory result. Finally, some proposals concerning the use of this mathematical <span class="hlt">model</span> in a flight simulator are given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNG31A1561B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNG31A1561B"><span>Forecast improvement by interactive ensemble of <span class="hlt">atmospheric</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Basnarkov, L.; Duane, G. S.; Kocarev, L.</p> <p>2013-12-01</p> <p>The advances in weather forecast traditionally have been based on two lines of improvement: 1 - deepening the understanding of physical phenomena that underlies the <span class="hlt">atmospheric</span> dynamics; and 2 - steady increase in computer power that enables use of finer grid resolution. The meteorological centers <span class="hlt">model</span> dynamics of the <span class="hlt">atmosphere</span> with the same basic physical laws, but sometimes take different approaches in capturing small-scale phenomena and generally use different grid sizes. As a result there are dozens operational <span class="hlt">models</span> around the globe with various parameterizations of the unresolved processes. Newest attempts in forecast improvements are based on using ensemble prediction. Multiple outputs are taken from runs with perturbed initial conditions, or perturbed parameter values. A novel paradigm is exploiting dynamical exchange of variables between simultaneously running <span class="hlt">models</span>. There are already simulations of <span class="hlt">models</span> exchanging fluxes between ocean and <span class="hlt">atmospheric</span> <span class="hlt">models</span>, but examples with direct coupling of different <span class="hlt">atmospheric</span> <span class="hlt">models</span> are rather new. Within this approach the coupling schemes can be different, but as simplest appear those that combine corresponding dynamical variables or tendency components. In this work we present results with an artificial toy <span class="hlt">model</span>-Lorenz 96 <span class="hlt">model</span>. To make more faithful example as reality (the <span class="hlt">atmosphere</span>) is considered one Lorenz 96 class III system, while as its imperfect <span class="hlt">models</span> are taken three class II systems that have different forcing terms. These resemble the <span class="hlt">models</span> used in three different meteorological centers. The interactive ensemble has tendency that is weighted combination of the individual <span class="hlt">models</span>' tendencies. The weights are obtained with statistical techniques based on past observations that target to minimize the mismatch between the truth's and interactive ensemble's tendencies. By means of anomaly correlation it is numerically verified that this ensemble has longer range of forecast than the individual <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009GBioC..23.4021G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009GBioC..23.4021G"><span><span class="hlt">Atmosphere</span>-ocean ozone exchange: A global <span class="hlt">modeling</span> study of biogeochemical, <span class="hlt">atmospheric</span>, and waterside turbulence dependencies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ganzeveld, L.; Helmig, D.; Fairall, C. W.; Hare, J.; Pozzer, A.</p> <p>2009-12-01</p> <p>The significance of the removal of tropospheric ozone by the oceans, covering ˜2/3 of the Earth's surface, has only been addressed in a few studies involving water tank, aircraft, and tower flux measurements. On the basis of results from these few observations of the ozone dry deposition velocity (VdO3), <span class="hlt">atmospheric</span> chemistry <span class="hlt">models</span> generally apply an empirical, constant ocean uptake rate of 0.05 cm s-1. This value is substantially smaller than the <span class="hlt">atmospheric</span> turbulent transport velocity for ozone. On the other hand, the uptake is higher than expected from the solubility of ozone in clean water alone, suggesting that there is an enhancement in oceanic ozone uptake, e.g., through a chemical destruction mechanism. We present an evaluation of a global-scale analysis with a new mechanistic representation of <span class="hlt">atmosphere</span>-ocean ozone exchange. The applied <span class="hlt">atmosphere</span> chemistry-climate <span class="hlt">model</span> includes not only <span class="hlt">atmospheric</span> but also waterside turbulence and the role of waterside chemical loss processes as a function of oceanic biogeochemistry. The simulations suggest a larger role of biogeochemistry in tropical and subtropical ozone oceanic uptake with a relative small temporal variability, whereas in midlatitude and high-latitude regions, highly variable ozone uptake rates are expected because of the stronger influence of waterside turbulence. Despite a relatively large range in the explicitly calculated ocean uptake rate, there is a surprisingly small sensitivity of simulated Marine Boundary Layer ozone concentrations compared to the sensitivity for the commonly applied constant ocean uptake approach. This small sensitivity points at compensating effects through inclusion of the process-based ocean uptake mechanisms to consider variability in oceanic O3 deposition consistent with that in <span class="hlt">atmospheric</span> and oceanic physical, chemical, and biological processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28422476','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28422476"><span>Origin-Dependent Variations in the <span class="hlt">Atmospheric</span> Microbiome <span class="hlt">Community</span> in Eastern Mediterranean Dust Storms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gat, Daniella; Mazar, Yinon; Cytryn, Eddie; Rudich, Yinon</p> <p>2017-06-20</p> <p>Microorganisms carried by dust storms are transported through the <span class="hlt">atmosphere</span> and may affect human health and the functionality of microbial <span class="hlt">communities</span> in various environments. Characterizing the dust-borne microbiome in dust storms of different origins or that followed different trajectories provides valuable data to improve our understanding of global health and environmental impacts. We present a comparative study on the diversity of dust-borne bacterial <span class="hlt">communities</span> in dust storms from three distinct origins (North Africa, Syria and Saudi Arabia) and compare them with local bacterial <span class="hlt">communities</span> sampled on clear days, all collected at a single location: Rehovot, Israel. Storms from different dust origins exhibited distinct bacterial <span class="hlt">communities</span>, with signature bacterial taxa. Dust storms were characterized by a lower abundance of selected antibiotic resistance genes (ARGs) compared with ambient dust, asserting that the origin of these genes is local and possibly anthropogenic. With the progression of the storm, the storm-borne bacterial <span class="hlt">community</span> showed increasing resemblance to ambient dust, suggesting mixing with local dust. These results show, for the first time, that dust storms from different sources display distinct bacterial <span class="hlt">communities</span>, suggesting possible diverse effects on the environment and public health.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ECSS..153...18M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ECSS..153...18M"><span>Impact of <span class="hlt">atmospheric</span> deposition on the metabolism of coastal microbial <span class="hlt">communities</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martínez-García, Sandra; Arbones, B.; García-Martín, E. E.; Teixeira, I. G.; Serret, P.; Fernández, E.; Figueiras, F. G.; Teira, E.; Álvarez-Salgado, X. A.</p> <p>2015-02-01</p> <p>The impact of rain water collected at marine, urban and rural sites on coastal phytoplankton biomass, primary production and <span class="hlt">community</span> composition as well as the effect on microbial plankton metabolism was studied in 3 microcosm experiments conducted under contrasting spring, autumn and winter conditions. The measured responses were highly variable. Rainwater additions increased chlorophyll a (Chl a) concentration (5-68% difference between rainwater treatments relative to the control) in all experiments and reduced or stimulated primary production (PP) depending on the treatment and the experiment (from -10 to +169% relative to the control). Autotrophic stimulation was highest in spring, probably related to the low initial natural nutrient concentrations. Under winter nutrient replete conditions, rainwater inputs changed the phytoplankton <span class="hlt">community</span> although this change did not promote increases in primary production. Enhancement of net autotrophy (increase of net oxygen production up to 227%) after rainwater inputs were only found during the period of low nutrient availability. Inputs of dissolved organic nitrogen (DON) explained a large fraction of the variability in the response of PP, Chl a, <span class="hlt">community</span> respiration (CR) and net <span class="hlt">community</span> production (NCP). Our results suggest that differences in the initial environmental conditions (i.e. nutrient availability), rainwater composition and the ability of the present autotrophic <span class="hlt">communities</span> to utilize the new nutrients result in substantial changes in the microbial responses and associated biologically-mediated carbon fluxes. As <span class="hlt">atmospheric</span> nutrient inputs into coastal oceans are increasing rapidly, our results help to understand the effects of different inputs on the metabolism of distinct microbial <span class="hlt">communities</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=312035&keyword=Latest&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=312035&keyword=Latest&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Evaluation of the <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">model</span> version 5.1</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">model</span> is a state-of-the-science air quality <span class="hlt">model</span> that simulates the emission, transport and fate of numerous air pollutants, including ozone and particulate matter. The <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> and Analysis Division (AMAD) of the U.S. Environment...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=312035&keyword=Scientific+AND+Work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78751495&CFTOKEN=85972416','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=312035&keyword=Scientific+AND+Work&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78751495&CFTOKEN=85972416"><span>Evaluation of the <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">model</span> version 5.1</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The <span class="hlt">Community</span> Multiscale Air Quality <span class="hlt">model</span> is a state-of-the-science air quality <span class="hlt">model</span> that simulates the emission, transport and fate of numerous air pollutants, including ozone and particulate matter. The <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> and Analysis Division (AMAD) of the U.S. Environment...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1523P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1523P"><span><span class="hlt">Modeling</span> Planetary <span class="hlt">Atmospheric</span> Energy Deposition By Energetic Ions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parkinson, Christopher; Bougher, Stephen; Gronoff, Guillaume; Barthelemy, Mathieu</p> <p>2016-07-01</p> <p>The structure, dynamics, chemistry, and evolution of planetary upper <span class="hlt">atmospheres</span> are in large part determined by the available sources of energy. In addition to the solar EUV flux, the solar wind and solar energetic particle (SEP) events are also important sources. Both of these particle populations can significantly affect an <span class="hlt">atmosphere</span>, causing <span class="hlt">atmospheric</span> loss and driving chemical reactions. Attention has been paid to these sources from the standpoint of the radiation environment for humans and electronics, but little work has been done to evaluate their impact on planetary <span class="hlt">atmospheres</span>. At unmagnetized planets or those with crustal field anomalies, in particular, the solar wind and SEPs of all energies have direct access to the <span class="hlt">atmosphere</span> and so provide a more substantial energy source than at planets having protective global magnetic fields. Additionally, solar wind and energetic particle fluxes should be more significant for planets orbiting more active stars, such as is the case in the early history of the solar system for paleo-Venus and Mars. Therefore quantification of the <span class="hlt">atmospheric</span> energy input from the solar wind and SEP events is an important component of our understanding of the processes that control their state and evolution. We have applied a full Lorentz motion particle transport <span class="hlt">model</span> to study the effects of particle precipitation in the upper <span class="hlt">atmospheres</span> of Mars and Venus. Such <span class="hlt">modeling</span> has been previously done for Earth and Mars using a guiding center precipitation <span class="hlt">model</span>. Currently, this code is only valid for particles with small gyroradii in strong uniform magnetic fields. There is a clear necessity for a Lorentz formulation, hence, a systematic study of the ionization, excitation, and energy deposition has been conducted, including a comparison of the influence relative to other energy sources (namely EUV photons). The result is a robust examination of the influence of energetic ion transport on the Venus and Mars upper <span class="hlt">atmosphere</span> which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhDT.......166R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhDT.......166R"><span><span class="hlt">Atmospheric</span> Circulation on Hot Jupiters: <span class="hlt">Modeling</span> and Observable Signatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rauscher, Emily Christine</p> <p>2010-12-01</p> <p>Hot Jupiters are unlike any planets in our Solar System and yet one of the most common types of extrasolar planet discovered. These gas giants orbit their parent stars with periods of a few days. Expected to be tidally locked into synchronous rotation, hot Jupiters experience intense, asymmetric heating from stellar irradiation, such that day-night temperature contrasts could reach hundreds of degrees Kelvin. This unique state of radiative forcing, as well as the slow rotation rates of these planets, places hot Jupiters within a new regime of <span class="hlt">atmospheric</span> circulation. Hot Jupiters have also been the first type of extrasolar planet with direct detections of their <span class="hlt">atmospheres</span>, through measurements of emitted, reflected, and transmitted light. This thesis investigates observational methods to distinguish between various <span class="hlt">atmospheric</span> <span class="hlt">models</span>, observational signatures of potential <span class="hlt">atmospheric</span> variability, and presents a three dimensional <span class="hlt">model</span> with which to study hot Jupiter circulation patterns. First, we find that eclipse mapping is a technique that can be used to image the day sides of these planets and although this is beyond the ability of current instruments, it will be achievable with future missions, such as the James Webb Space Telescope. Second, we consider the signatures of large-scale <span class="hlt">atmospheric</span> variability in measurements of secondary eclipses and thermal orbital phase curves. For various <span class="hlt">models</span> we predict the amount of variation in eclipse depth, and the amplitudes and detailed shapes of phase curves. Lastly, we develop a three-dimensional <span class="hlt">model</span> of hot Jupiter <span class="hlt">atmospheric</span> dynamics with simplified forcing and adopt a set-up nearly identical to work by another group to facilitate code inter-comparison. Our results are broadly consistent with theirs, with a transonic flow and the hottest region of the <span class="hlt">atmosphere</span> advected eastward of the substellar point. However, we note important differences and identify areas of concern for future <span class="hlt">modeling</span> efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSM52C..08K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSM52C..08K"><span>IMPACT: Integrated <span class="hlt">Modeling</span> of Perturbations in <span class="hlt">Atmospheres</span> for Conjunction Tracking</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koller, J.; Brennan, S.; Godinez, H. C.; Higdon, D. M.; Klimenko, A.; Larsen, B.; Lawrence, E.; Linares, R.; McLaughlin, C. A.; Mehta, P. M.; Palmer, D.; Ridley, A. J.; Shoemaker, M.; Sutton, E.; Thompson, D.; Walker, A.; Wohlberg, B.</p> <p>2013-12-01</p> <p>Low-Earth orbiting satellites suffer from <span class="hlt">atmospheric</span> drag due to thermospheric density which changes on the order of several magnitudes especially during space weather events. Solar flares, precipitating particles and ionospheric currents cause the upper <span class="hlt">atmosphere</span> to heat up, redistribute, and cool again. These processes are intrinsically included in empirical <span class="hlt">models</span>, e.g. MSIS and Jacchia-Bowman type <span class="hlt">models</span>. However, sensitivity analysis has shown that <span class="hlt">atmospheric</span> drag has the highest influence on satellite conjunction analysis and empirical <span class="hlt">model</span> still do not adequately represent a desired accuracy. Space debris and collision avoidance have become an increasingly operational reality. It is paramount to accurately predict satellite orbits and include drag effect driven by space weather. The IMPACT project (Integrated <span class="hlt">Modeling</span> of Perturbations in <span class="hlt">Atmospheres</span> for Conjunction Tracking), funded with over $5 Million by the Los Alamos Laboratory Directed Research and Development office, has the goal to develop an integrated system of <span class="hlt">atmospheric</span> drag <span class="hlt">modeling</span>, orbit propagation, and conjunction analysis with detailed uncertainty quantification to address the space debris and collision avoidance problem. Now with over two years into the project, we have developed an integrated solution combining physics-based density <span class="hlt">modeling</span> of the upper <span class="hlt">atmosphere</span> between 120-700 km altitude, satellite drag forecasting for quiet and disturbed geomagnetic conditions, and conjunction analysis with non-Gaussian uncertainty quantification. We are employing several novel approaches including a unique observational sensor developed at Los Alamos; machine learning with a support-vector machine approach of the coupling between solar drivers of the upper <span class="hlt">atmosphere</span> and satellite drag; rigorous data assimilative <span class="hlt">modeling</span> using a physics-based approach instead of empirical <span class="hlt">modeling</span> of the thermosphere; and a computed-tomography method for extracting temporal maps of thermospheric densities</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140823&keyword=static+AND+dynamic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78001885&CFTOKEN=57287486','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140823&keyword=static+AND+dynamic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78001885&CFTOKEN=57287486"><span>THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span> EVALUATION TOOL (AMET); AIR QUALITY MODULE</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This presentation reviews the development of the <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Evaluation Tool (AMET) air quality module. The AMET tool is being developed to aid in the <span class="hlt">model</span> evaluation. This presentation focuses on the air quality evaluation portion of AMET. Presented are examples of the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=160407&keyword=wind+AND+tunnel&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90550376&CFTOKEN=31112438','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=160407&keyword=wind+AND+tunnel&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=90550376&CFTOKEN=31112438"><span>NEAR ROADWAY RESEARCH IN THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODELING</span> DIVISION</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This is a presentation to the CRC Mobile Source Air Toxics Workshop in Phoenix, AZ, on 23 October 2006. The presentation provides an overview of air quality <span class="hlt">modeling</span> research in the USEPA/ORD/NERL's <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> Division, with an emphasis on near-road pollutant character...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140823&keyword=Model+AND+Transport+AND+Research+AND+Operational&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=140823&keyword=Model+AND+Transport+AND+Research+AND+Operational&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>THE <span class="hlt">ATMOSPHERIC</span> <span class="hlt">MODEL</span> EVALUATION TOOL (AMET); AIR QUALITY MODULE</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>This presentation reviews the development of the <span class="hlt">Atmospheric</span> <span class="hlt">Model</span> Evaluation Tool (AMET) air quality module. The AMET tool is being developed to aid in the <span class="hlt">model</span> evaluation. This presentation focuses on the air quality evaluation portion of AMET. Presented are examples of the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12..275V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12..275V"><span>Assessment of <span class="hlt">Atmosphere</span>-Ocean General Circulation <span class="hlt">Model</span> Simulations of Winter Northern Hemisphere <span class="hlt">Atmospheric</span> Blocking</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vial, Jessica; Osborn, Tim</p> <p>2010-05-01</p> <p>Characterized by their persistence and quasi-stationary features, large-scale <span class="hlt">atmospheric</span> blocking are often responsible for extreme weather events, which can have enormous impacts on human life, economy and environment e.g. European heat wave in summer 2003. Therefore, diagnostics of the present-day climate and future projections of potential changes in blocking-related extreme events are essential for risk management and adaptation planning. This study focuses on assessing the ability of six coupled <span class="hlt">Atmosphere</span>-Ocean General Circulation <span class="hlt">Models</span> (AOGCMs) to simulate large-scale winter <span class="hlt">atmospheric</span> blocking in the Northern Hemisphere for the present-day climate (1957-1999). A modified version of the Tibaldi and Molteni (1990)'s blocking index, which measures the strength of the average westerly flow in the mid-latitudes, is applied to daily averaged 500 hPa geopotential height output from the climate <span class="hlt">models</span>. ERA-40 re-analysis <span class="hlt">atmospheric</span> data have also been used over the same time period to verify the <span class="hlt">models</span>' results. The two preferred regions of blocking development, in the Euro-Atlantic and North Pacific, are well captured by most of the <span class="hlt">models</span>. However, the prominent error in blocking simulations, according to a number of previous <span class="hlt">model</span> assessments, consists of an underestimation of the total frequency of blocking episodes over both regions. A more detailed analysis of blocking frequency as a function of duration revealed that this error was due to an insufficient number of medium spells and long-lasting episodes, and a shift in blocking lifetime distributions towards shorter blocks, while short-lived blocking events (between 5 and 8 days) tend to be overestimated. The impact of <span class="hlt">models</span>' systematic errors on blocking simulations has been analyzed, and results suggest that there is a primary need to reduce the time-mean bias to improve the representation of blocking in climate <span class="hlt">models</span>. The underestimated high-frequency variability of the transient eddies embedded in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5677757','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5677757"><span><span class="hlt">Modeled</span> <span class="hlt">atmospheric</span> radon concentrations from uranium mines</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Droppo, J.G.</p> <p>1985-04-01</p> <p>Uranium mining and milling operations result in the release of radon from numerous sources of various types and strengths. The US Environmental Protection Agency (EPA) under the Clean Air Act, is assessing the health impact of air emissions of radon from underground uranium mines. In this case, the radon emissions may impact workers and residents in the mine vicinity. To aid in this assessment, the EPA needs to know how mine releases can affect the radon concentrations at populated locations. To obtain this type of information, Pacific Northwest Laboratory used the radon emissions, release characteristics and local meterological conditions for a number of mines to <span class="hlt">model</span> incremental radon concentrations. Long-term, average, incremental radon concentrations were computed based on the best available information on release rates, plume rise parameters, number and locations of vents, and local dispersion climatology. Calculations are made for a <span class="hlt">model</span> mine, individual mines, and multiple mines. Our approach was to start with a general case and then consider specific cases for comparison. A <span class="hlt">model</span> underground uranium mine was used to provide definition of the order of magnitude of typical impacts. Then computations were made for specific mines using the best mine-specific information available for each mine. These case study results are expressed as predicted incremental radon concentration contours plotted on maps with local population data from a previous study. Finally, the effect of possible overlap of radon releases from nearby mines was studied by calculating cumulative radon concentrations for multiple mines in a region with many mines. The dispersion <span class="hlt">model</span>, <span class="hlt">modeling</span> assumptions, data sources, computational procedures, and results are documented in this report. 7 refs., 27 figs., 18 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC13C0642P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC13C0642P"><span>THE Antarctic <span class="hlt">Atmospheric</span> Energy Budget: Observations and <span class="hlt">Model</span> Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Previdi, M. J.; Smith, K. L.; Polvani, L. M.</p> <p>2014-12-01</p> <p>We present a new, observationally-based estimate of the <span class="hlt">atmospheric</span> energy budget for the Antarctic polar cap (the region poleward of 70°S). This energy budget is constructed using state-of-the-art reanalysis products from ECMWF [the ECMWF Interim Re-Analysis (ERA-Interim)] and Clouds and the Earth's Radiant Energy System (CERES) top-of-<span class="hlt">atmosphere</span> (TOA) radiative fluxes. We find that the climatological mean Antarctic energy budget is characterized by an approximate balance between the TOA net outgoing radiation and the horizontal convergence of <span class="hlt">atmospheric</span> energy transport, with the net surface energy flux and <span class="hlt">atmospheric</span> energy storage generally being small in comparison. We compare these observationally-based results with coupled <span class="hlt">atmosphere</span>-ocean general circulation <span class="hlt">model</span> simulations that have been made available as part of the Coupled <span class="hlt">Model</span> Intercomparison Project, phase 5 (CMIP5). While CMIP5 <span class="hlt">models</span> generally perform well in simulating the observed climatological mean energy budget, some notable <span class="hlt">model</span> biases are apparent. These biases are most pronounced during the austral summer and fall seasons, with the largest biases (approaching 30 W m-2 for some <span class="hlt">models</span>) occurring for the TOA net incoming shortwave radiation during summer. Finally, we examine the causes of <span class="hlt">model</span> biases (e.g., deficiencies in the simulated cloud cover and sea ice), as well as their relationship to the simulated twenty-first century trends in the energy budget. We find a statistically significant inverse correlation across the CMIP5 <span class="hlt">models</span> between the present-day biases in <span class="hlt">atmospheric</span> energy transport into the polar cap, and the simulated future changes in energy transport over the twenty-first century. Possible reasons for this relationship are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015BoLMe.154..427S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015BoLMe.154..427S"><span>Interfacing the Urban Land-<span class="hlt">Atmosphere</span> System Through Coupled Urban Canopy and <span class="hlt">Atmospheric</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Jiyun; Wang, Zhi-Hua</p> <p>2015-03-01</p> <p>We couple a single column <span class="hlt">model</span> (SCM) to a cutting-edge single-layer urban canopy <span class="hlt">model</span> (SLUCM) with realistic representation of urban hydrological processes. The land-surface transport of energy and moisture parametrized by the SLUCM provides lower boundary conditions to the overlying <span class="hlt">atmosphere</span>. The coupled SLUCM-SCM <span class="hlt">model</span> is tested against field measurements of sensible and latent heat fluxes in the surface layer, as well as vertical profiles of temperature and humidity in the mixed layer under convective conditions. The <span class="hlt">model</span> is then used to simulate urban land-<span class="hlt">atmosphere</span> interactions by changing urban geometry, surface albedo, vegetation fraction and aerodynamic roughness. Results show that changes of landscape characteristics have a significant impact on the growth of the boundary layer as well as on the distributions of temperature and humidity in the mixed layer. Overall, the proposed numerical framework provides a useful stand-alone <span class="hlt">modelling</span> tool, with which the impact of urban land-surface conditions on the local hydrometeorology can be assessed via land-<span class="hlt">atmosphere</span> interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940002998&hterms=worldwide+statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dworldwide%2Bstatistics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940002998&hterms=worldwide+statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dworldwide%2Bstatistics"><span>GRAM 88 - 4D GLOBAL REFERENCE <span class="hlt">ATMOSPHERE</span> <span class="hlt">MODEL</span>-1988</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, D. L.</p> <p>1994-01-01</p> <p>The Four-D Global Reference <span class="hlt">Atmosphere</span> program was developed from an empirical <span class="hlt">atmospheric</span> <span class="hlt">model</span> which generates values for pressure, density, temperature, and winds from surface level to orbital altitudes. This program can generate altitude profiles of <span class="hlt">atmospheric</span> parameters along any simulated trajectory through the <span class="hlt">atmosphere</span>. The program was developed for design applications in the Space Shuttle program, such as the simulation of external tank re-entry trajectories. Other potential applications are global circulation and diffusion studies; also the generation of profiles for comparison with other <span class="hlt">atmospheric</span> measurement techniques such as satellite measured temperature profiles and infrasonic measurement of wind profiles. GRAM-88 is the latest version of the software GRAM. The software GRAM-88 contains a number of changes that have improved the <span class="hlt">model</span> statistics, in particular, the small scale density perturbation statistics. It also corrected a low latitude grid problem as well as the SCIDAT data base. Furthermore, GRAM-88 now uses the U.S. Standard <span class="hlt">Atmosphere</span> 1976 as a comparison standard rather than the US62 used in other versions. The program is an amalgamation of two empirical <span class="hlt">atmospheric</span> <span class="hlt">models</span> for the low (25km) and the high (90km) <span class="hlt">atmosphere</span>, with a newly developed latitude-longitude dependent <span class="hlt">model</span> for the middle <span class="hlt">atmosphere</span>. The Jacchia (1970) <span class="hlt">model</span> simulates the high <span class="hlt">atmospheric</span> region above 115km. The Jacchia program sections are in separate subroutines so that other thermosphericexospheric <span class="hlt">models</span> could easily be adapted if required for special applications. The improved code eliminated the calculation of geostrophic winds above 125 km altitude from the <span class="hlt">model</span>. The <span class="hlt">atmospheric</span> region between 30km and 90km is simulated by a latitude-longitude dependent empirical <span class="hlt">model</span> modification of the latitude dependent empirical <span class="hlt">model</span> of Groves (1971). A fairing technique between 90km and 115km accomplished a smooth transition between the modified Groves values and</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110014525','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110014525"><span>Onboard <span class="hlt">Atmospheric</span> <span class="hlt">Modeling</span> and Prediction for Autonomous Aerobraking Missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tolson, Robert H.; Prince, Jill L. H.</p> <p>2011-01-01</p> <p>Aerobraking has proven to be an effective means of increasing the science payload for planetary orbiting missions and/or for enabling the use of less expensive launch vehicles. Though aerobraking has numerous benefits, large operations cost have been required to maintain the aerobraking time line without violating aerodynamic heating or other constraints. Two operations functions have been performed on an orbit by orbit basis to estimate <span class="hlt">atmospheric</span> properties relevant to aerobraking. The Navigation team typically solves for an <span class="hlt">atmospheric</span> density scale factor using DSN tracking data and the <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> team uses telemetric accelerometer data to recover <span class="hlt">atmospheric</span> density profiles. After some effort, decisions are made about the need for orbit trim maneuvers to adjust periapsis altitude to stay within the aerobraking corridor. Autonomous aerobraking would reduce the need for many ground based tasks. To be successful, <span class="hlt">atmospheric</span> <span class="hlt">modeling</span> must be performed on the vehicle in near real time. This paper discusses the issues associated with estimating the planetary <span class="hlt">atmosphere</span> onboard and evaluates a number of the options for Mars, Venus and Titan aerobraking missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.9726H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.9726H"><span><span class="hlt">Models</span> of ash-laden intrusions in a stratified <span class="hlt">atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hogg, Andrew; Johnson, Chris; Sparks, Steve; Huppert, Herbert; Woodhouse, Mark; Phillips, Jeremy</p> <p>2013-04-01</p> <p>Recent volcanic eruptions and the associated dispersion of ash through the <span class="hlt">atmosphere</span> have led to widespread closures of airspace, for example the 2010 eruption of Eyjafjallajokull and 2011 eruption of Puyehue-Cordón Caulle. These episodes bring into sharp focus the need to predict quantitatively the transport and deposition of fine ash and in particular, its interaction with <span class="hlt">atmospheric</span> wind. Many <span class="hlt">models</span> of this process are based upon capturing the physics of advection with the wind, turbulence-induced diffusion and gravitational settling. Buoyancy-induced processes, associated with the density of the ash cloud and the background stratification of the <span class="hlt">atmosphere</span>, are neglected and it is this issue that we address in this contribution. In particular, we suggest that the buoyancy-induced motion may account for the relatively thin distal ash layers that have been observed in the <span class="hlt">atmosphere</span> and their relatively weak cross-wind spreading. We formulate a new <span class="hlt">model</span> for buoyancy-driven spreading in the <span class="hlt">atmosphere</span> in which we treat the evolving ash layer as relatively shallow so that its motion is predominantly horizontal and the pressure locally hydrostatic. The motion is driven by horizontal pressure gradients along with interfacial drag between the flowing ash layer and the surrounding <span class="hlt">atmosphere</span>. Ash-laden fluid is delivered to this intrusion from a plume source and has risen through the <span class="hlt">atmosphere</span> to its height of neutral buoyancy. The ash particles are then transported horizontally by the intrusion and progressively settle out of it to sediment through the <span class="hlt">atmosphere</span> and form the deposit on the ground. This <span class="hlt">model</span> is integrated numerically and analysed asymptotically in various regimes, including scenarios in which the <span class="hlt">atmosphere</span> is quiescent and in which there is a sustained wind. The results yield predictions for the variation of the thickness of the intrusion with distance from the source and for how the concentration of ash is reduced due to settling. They</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4969754','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4969754"><span>Light self-focusing in the <span class="hlt">atmosphere</span>: thin window <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Vaseva, Irina A.; Fedoruk, Mikhail P.; Rubenchik, Alexander M.; Turitsyn, Sergei K.</p> <p>2016-01-01</p> <p>Ultra-high power (exceeding the self-focusing threshold by more than three orders of magnitude) light beams from ground-based laser systems may find applications in space-debris cleaning. The propagation of such powerful laser beams through the <span class="hlt">atmosphere</span> reveals many novel interesting features compared to traditional light self-focusing. It is demonstrated here that for the relevant laser parameters, when the thickness of the <span class="hlt">atmosphere</span> is much shorter than the focusing length (that is, of the orbit scale), the beam transit through the <span class="hlt">atmosphere</span> in lowest order produces phase distortion only. This means that by using adaptive optics it may be possible to eliminate the impact of self-focusing in the <span class="hlt">atmosphere</span> on the laser beam. The area of applicability of the proposed “thin window” <span class="hlt">model</span> is broader than the specific physical problem considered here. For instance, it might find applications in femtosecond laser material processing. PMID:27480220</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1297640-light-self-focusing-atmosphere-thin-window-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1297640-light-self-focusing-atmosphere-thin-window-model"><span>Light self-focusing in the <span class="hlt">atmosphere</span>: Thin window <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Vaseva, Irina A.; Fedoruk, Mikhail P.; Rubenchik, Alexander M.; ...</p> <p>2016-08-02</p> <p>Ultra-high power (exceeding the self-focusing threshold by more than three orders of magnitude) light beams from ground-based laser systems may find applications in space-debris cleaning. The propagation of such powerful laser beams through the <span class="hlt">atmosphere</span> reveals many novel interesting features compared to traditional light self-focusing. It is demonstrated here that for the relevant laser parameters, when the thickness of the <span class="hlt">atmosphere</span> is much shorter than the focusing length (that is, of the orbit scale), the beam transit through the <span class="hlt">atmosphere</span> in lowest order produces phase distortion only. This means that by using adaptive optics it may be possible to eliminatemore » the impact of self-focusing in the <span class="hlt">atmosphere</span> on the laser beam. Furthermore, the area of applicability of the proposed “thin window” <span class="hlt">model</span> is broader than the specific physical problem considered here. For instance, it might find applications in femtosecond laser material processing.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1297640','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1297640"><span>Light self-focusing in the <span class="hlt">atmosphere</span>: Thin window <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vaseva, Irina A.; Fedoruk, Mikhail P.; Rubenchik, Alexander M.; Turitsyn, Sergei K.</p> <p>2016-08-02</p> <p>Ultra-high power (exceeding the self-focusing threshold by more than three orders of magnitude) light beams from ground-based laser systems may find applications in space-debris cleaning. The propagation of such powerful laser beams through the <span class="hlt">atmosphere</span> reveals many novel interesting features compared to traditional light self-focusing. It is demonstrated here that for the relevant laser parameters, when the thickness of the <span class="hlt">atmosphere</span> is much shorter than the focusing length (that is, of the orbit scale), the beam transit through the <span class="hlt">atmosphere</span> in lowest order produces phase distortion only. This means that by using adaptive optics it may be possible to eliminate the impact of self-focusing in the <span class="hlt">atmosphere</span> on the laser beam. Furthermore, the area of applicability of the proposed “thin window” <span class="hlt">model</span> is broader than the specific physical problem considered here. For instance, it might find applications in femtosecond laser material processing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...630697V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...630697V"><span>Light self-focusing in the <span class="hlt">atmosphere</span>: thin window <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vaseva, Irina A.; Fedoruk, Mikhail P.; Rubenchik, Alexander M.; Turitsyn, Sergei K.</p> <p>2016-08-01</p> <p>Ultra-high power (exceeding the self-focusing threshold by more than three orders of magnitude) light beams from ground-based laser systems may find applications in space-debris cleaning. The propagation of such powerful laser beams through the <span class="hlt">atmosphere</span> reveals many novel interesting features compared to traditional light self-focusing. It is demonstrated here that for the relevant laser parameters, when the thickness of the <span class="hlt">atmosphere</span> is much shorter than the focusing length (that is, of the orbit scale), the beam transit through the <span class="hlt">atmosphere</span> in lowest order produces phase distortion only. This means that by using adaptive optics it may be possible to eliminate the impact of self-focusing in the <span class="hlt">atmosphere</span> on the laser beam. The area of applicability of the proposed “thin window” <span class="hlt">model</span> is broader than the specific physical problem considered here. For instance, it might find applications in femtosecond laser material processing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27480220','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27480220"><span>Light self-focusing in the <span class="hlt">atmosphere</span>: thin window <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vaseva, Irina A; Fedoruk, Mikhail P; Rubenchik, Alexander M; Turitsyn, Sergei K</p> <p>2016-08-02</p> <p>Ultra-high power (exceeding the self-focusing threshold by more than three orders of magnitude) light beams from ground-based laser systems may find applications in space-debris cleaning. The propagation of such powerful laser beams through the <span class="hlt">atmosphere</span> reveals many novel interesting features compared to traditional light self-focusing. It is demonstrated here that for the relevant laser parameters, when the thickness of the <span class="hlt">atmosphere</span> is much shorter than the focusing length (that is, of the orbit scale), the beam transit through the <span class="hlt">atmosphere</span> in lowest order produces phase distortion only. This means that by using adaptive optics it may be possible to eliminate the impact of self-focusing in the <span class="hlt">atmosphere</span> on the laser beam. The area of applicability of the proposed "thin window" <span class="hlt">model</span> is broader than the specific physical problem considered here. For instance, it might find applications in femtosecond laser material processing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040090188&hterms=Evolution+Controversy&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DEvolution%2BControversy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040090188&hterms=Evolution+Controversy&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DEvolution%2BControversy"><span>Box <span class="hlt">models</span> for the evolution of <span class="hlt">atmospheric</span> oxygen: an update</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kasting, J. F.</p> <p>1991-01-01</p> <p>A simple 3-box <span class="hlt">model</span> of the <span class="hlt">atmosphere</span>/ocean system is used to describe the various stages in the evolution of <span class="hlt">atmospheric</span> oxygen. In Stage I, which probably lasted until redbeds began to form about 2.0 Ga ago, the Earth's surface environment was generally devoid of free O2, except possibly in localized regions of high productivity in the surface ocean. In Stage II, which may have lasted for less than 150 Ma, the <span class="hlt">atmosphere</span> and surface ocean were oxidizing, while the deep ocean remained anoxic. In Stage III, which commenced with the disappearance of banded iron formations around 1.85 Ga ago and has lasted until the present, all three surface reservoirs contained appreciable amounts of free O2. Recent and not-so-recent controversies regarding the abundance of oxygen in the Archean <span class="hlt">atmosphere</span> are identified and discussed. The rate of O2 increase during the Middle and Late Proterozoic is identified as another outstanding question.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.4338J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.4338J"><span>Challenges in <span class="hlt">Modeling</span> of the Global <span class="hlt">Atmosphere</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Janjic, Zavisa; Djurdjevic, Vladimir; Vasic, Ratko; Black, Tom</p> <p>2015-04-01</p> <p>The massively parallel computer architectures require that some widely adopted <span class="hlt">modeling</span> paradigms be reconsidered in order to utilize more productively the power of parallel processing. For high computational efficiency with distributed memory, each core should work on a small subdomain of the full integration domain, and exchange only few rows of halo data with the neighbouring cores. However, the described scenario implies that the discretization used in the <span class="hlt">model</span> is horizontally local. The spherical geometry further complicates the problem. Various grid topologies will be discussed and examples will be shown. The latitude-longitude grid with local in space and explicit in time differencing has been an early choice and remained in use ever since. The problem with this method is that the grid size in the longitudinal direction tends to zero as the poles are approached. So, in addition to having unnecessarily high resolution near the poles, polar filtering has to be applied in order to use a time step of decent size. However, the polar filtering requires transpositions involving extra communications. The spectral transform method and the semi-implicit semi-Lagrangian schemes opened the way for a wide application of the spectral representation. With some variations, these techniques are used in most major centers. However, the horizontal non-locality is inherent to the spectral representation and implicit time differencing, which inhibits scaling on a large number of cores. In this respect the lat-lon grid with a fast Fourier transform represents a significant step in the right direction, particularly at high resolutions where the Legendre transforms become increasingly expensive. Other grids with reduced variability of grid distances such as various versions of the cubed sphere and the hexagonal/pentagonal ("soccer ball") grids were proposed almost fifty years ago. However, on these grids, large-scale (wavenumber 4 and 5) fictitious solutions ("grid imprinting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA623759','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA623759"><span>Mesoscale <span class="hlt">Modeling</span> of the <span class="hlt">Atmosphere</span> and Aerosols</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2000-09-30</p> <p>fires, or the dynamical and topographical forcing is small-scale, as in dust storms . A high-resolution COAMPS is needed to simulate the first stages of...context. However, the tightly coupled application is practical only for dynamically driven aerosols (e.g. dust storms ) or for planned (e.g. known...an imbedded aerosol module for COAMPS for use in the design and evaluation of techniques for coupling off-line transport and dispersion <span class="hlt">models</span> to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140016394','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140016394"><span>Mars Entry <span class="hlt">Atmospheric</span> Data System <span class="hlt">Modeling</span>, Calibration, and Error Analysis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Karlgaard, Christopher D.; VanNorman, John; Siemers, Paul M.; Schoenenberger, Mark; Munk, Michelle M.</p> <p>2014-01-01</p> <p>The Mars Science Laboratory (MSL) Entry, Descent, and Landing Instrumentation (MEDLI)/Mars Entry <span class="hlt">Atmospheric</span> Data System (MEADS) project installed seven pressure ports through the MSL Phenolic Impregnated Carbon Ablator (PICA) heatshield to measure heatshield surface pressures during entry. These measured surface pressures are used to generate estimates of <span class="hlt">atmospheric</span> quantities based on <span class="hlt">modeled</span> surface pressure distributions. In particular, the quantities to be estimated from the MEADS pressure measurements include the dynamic pressure, angle of attack, and angle of sideslip. This report describes the calibration of the pressure transducers utilized to reconstruct the <span class="hlt">atmospheric</span> data and associated uncertainty <span class="hlt">models</span>, pressure <span class="hlt">modeling</span> and uncertainty analysis, and system performance results. The results indicate that the MEADS pressure measurement system hardware meets the project requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...832..102M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...832..102M"><span><span class="hlt">Model</span> <span class="hlt">Atmospheres</span> for X-Ray Bursting Neutron Stars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Medin, Zach; von Steinkirch, Marina; Calder, Alan C.; Fontes, Christopher J.; Fryer, Chris L.; Hungerford, Aimee L.</p> <p>2016-12-01</p> <p>The hydrogen and helium accreted by X-ray bursting neutron stars is periodically consumed in runaway thermonuclear reactions that cause the entire surface to glow brightly in X-rays for a few seconds. With <span class="hlt">models</span> of the emission, the mass and radius of the neutron star can be inferred from the observations. By simultaneously probing neutron star masses and radii, X-ray bursts (XRBs) are one of the strongest diagnostics of the nature of matter at extremely high densities. Accurate determinations of these parameters are difficult, however, due to the highly non-ideal nature of the <span class="hlt">atmospheres</span> where XRBs occur. Observations from X-ray telescopes such as RXTE and NuStar can potentially place strong constraints on nuclear matter once uncertainties in <span class="hlt">atmosphere</span> <span class="hlt">models</span> have been reduced. Here we discuss current progress on <span class="hlt">modeling</span> <span class="hlt">atmospheres</span> of X-ray bursting neutron stars and some of the challenges still to be overcome.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1337104','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1337104"><span><span class="hlt">MODEL</span> <span class="hlt">ATMOSPHERES</span> FOR X-RAY BURSTING NEUTRON STARS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Medin, Zachary James; Steinkirch, Marina von; Calder, Alan C.; Fontes, Christopher J.; Fryer, Chris L.; Hungerford, Aimee L.</p> <p>2016-11-21</p> <p>The hydrogen and helium accreted by X-ray bursting neutron stars is periodically consumed in runaway thermonuclear reactions that cause the entire surface to glow brightly in X-rays for a few seconds. With <span class="hlt">models</span> of the emission, the mass and radius of the neutron star can be inferred from the observations. By simultaneously probing neutron star masses and radii, X-ray bursts (XRBs) are one of the strongest diagnostics of the nature of matter at extremely high densities. Accurate determinations of these parameters are difficult, however, due to the highly non-ideal nature of the <span class="hlt">atmospheres</span> where XRBs occur. Also, observations from X-ray telescopes such as RXTE and NuStar can potentially place strong constraints on nuclear matter once uncertainties in <span class="hlt">atmosphere</span> <span class="hlt">models</span> have been reduced. Lastly, here we discuss current progress on <span class="hlt">modeling</span> <span class="hlt">atmospheres</span> of X-ray bursting neutron stars and some of the challenges still to be overcome.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004EAS....11....3A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004EAS....11....3A"><span>The future of stellar <span class="hlt">model</span> <span class="hlt">atmospheres</span>: macroscopic nightmares?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Asplund, M.</p> <p></p> <p>Stellar <span class="hlt">atmospheres</span> represent unique windows for understanding stellar, galactic and cosmic evolution by being responsible for the emission of stellar spectra. Much progress has been made over the years in <span class="hlt">modelling</span> stellar <span class="hlt">atmospheres</span> but still the <span class="hlt">modelling</span> efforts are hampered by various, often questionable, assumptions and approximations. This review describes promising avenues for improving the realism of stellar <span class="hlt">model</span> <span class="hlt">atmospheres</span> for hot (spectral types O, B, A), cool (F, G, K) and very cool (M and later) stars, respectively, in the coming decade. A common theme will be time-dependent 3D hydrodynamical calculations with a detailed non-LTE treatment of the radiative transfer. It is argued that this is fully within the realm of possibility on this time-scale and indeed will be necessary to com