Science.gov

Sample records for nested mesoscale model

  1. A nested-grid mesoscale numerical weather prediction model modified for Space Shuttle operational requirements

    NASA Technical Reports Server (NTRS)

    Kaplan, M. L.; Zack, J. W.; Wong, V. C.; Coats, G. D.

    1983-01-01

    A nested-grid mesoscale atmospheric simulation system (MASS) is tested over Florida for the case of intense seabreeze-induced convection. The goal of this modeling system is to provide real-time aviation weather support which is designed to fit local terminal operations such as those supporting NASA's STS. Results from a 58 km and a 14.5 km nested-grid simulation show that this version of the MASS is capable of simulating many of the basic characteristics of convective complexes during periods of relatively weak synoptic scale flow regimes. However, it is noted that extensive development work is required with nested-grid cumulus and planetary boundary layer parameterization schemes before many of the meso-beta scale features such as thunderstorm downdraft-produced bubble high pressure centers can be accurately simulated. After these schemes are properly tuned, MASS can be utilized to initialize microscale modeling systems.

  2. Implementation of wind turbine parameterizations in a mesoscale-LES nested model framework

    NASA Astrophysics Data System (ADS)

    Chow, Fotini; Marjanovic, Nikola; Mirocha, Jeffrey

    2014-11-01

    Wind turbine performance depends on weather conditions, local topography, and wind turbine spacing, among other factors. Atmospheric simulations can be used to predict wind energy production at increasingly higher resolutions. Turbine models placed within such simulations can be used to investigate turbine operation and performance. This work describes the implementation of generalized actuator disk (GAD) and line (GAL) models into the Weather Research and Forecasting (WRF) mesoscale atmospheric model. WRF can be used in a grid nested configuration starting from the mesoscale (~10 km resolution) and ending with fine scale resolutions (~1-10 m) suitable for large-eddy simulations (LES). At LES scales it becomes possible to resolve both the thrust and torque forces generated on turbines and imparted to the atmosphere using GAD and GAL models. Both models include real-time yaw and pitch control to respond to changing flow conditions. Here, the GAD and GAL are tested for idealized and real model configurations and compared to data from a wind farm. Comparisons are also made that help determine the importance of turbine blade tilt away from the tower and the inclusion of tower and turbine hub drag effects.

  3. Applying different spatial distribution and modelling concepts in three nested mesoscale catchments of Germany

    NASA Astrophysics Data System (ADS)

    Bongartz, K.

    Distributed, physically based river basin models are receiving increasing importance in integrated water resources management (IWRM) in Germany and in Europe, especially after the release of the new European Water Framework Directive (WFD). Applications in mesoscale catchments require an appropriate approach to represent the spatial distribution of related catchment properties such as land use, soil physics and topography by utilizing techniques of remote sensing and GIS analyses. The challenge is to delineate scale independent homogeneous modelling entities which, on the one hand may represent the dynamics of the dominant hydrological processes and, on the other hand can be derived from spatially distributed physiographical catchment properties. This scaling problem is tackled in this regional modelling study by applying the concept of hydrological response units (HRUs). In a nested catchment approach three different modelling conceptualisations are used to describe the runoff processes: (i) the topographic stream-segment-based HRU delineation proposed by Leavesley et al. [Precipitation-Runoff-Modelling-System, User’s Manual, Water Resource Investigations Report 83-4238, US Geological Survey, 1983]; (ii) the process based physiographic HRU-concept introduced by Flügel [Hydrol. Process. 9 (1995) 423] and (iii) an advanced HRU-concept adapted from (ii), which included the topographic topology of HRU-areas and the river network developed by Staudenraush [Eco Regio 8 (2000) 121]. The influence of different boundary conditions associated with changing the landuse classes, the temporal data resolution and the landuse scenarios were investigated. The mesoscale catchment of the river Ilm ( A∼895 km 2) in Thuringia, Germany, and the Precipitation-Runoff-Modelling-System (PRMS) were selected for this study. Simulations show that the physiographic based concept is a reliable method for modelling basin dynamics in catchments up to 200 km 2 whereas in larger catchments

  4. Data assimilation of a ten-day period during June 1993 over the Southern Great Plains Site using a nested mesoscale model

    SciTech Connect

    Dudhia, J.; Guo, Y.R.

    1996-04-01

    A goal of the Atmospheric Radiation Measurement (ARM) Program has been to obtain a complete representation of physical processes on the scale of a general circulation model (GCM) grid box in order to better parameterize radiative processes in these models. Since an observational network of practical size cannot be used alone to characterize the Cloud and Radiation Testbed (CART) site`s 3D structure and time development, data assimilation using the enhanced observations together with a mesoscale model is used to give a full 4D analysis at high resolution. The National Center for Atmospheric Research (NCAR)/Penn State Mesoscale Model (MM5) has been applied over a ten-day continuous period in a triple-nested mode with grid sizes of 60, 20 and 6.67 in. The outer domain covers the United States` 48 contiguous states; the innermost is a 480-km square centered on Lamont, Oklahoma. A simulation has been run with data assimilation using the Mesoscale Analysis and Prediction System (MAPS) 60-km analyses from the Forecast Systems Laboratory (FSL) of the National Ocean and Atmospheric Administration (NOAA). The nested domains take boundary conditions from and feed back continually to their parent meshes (i.e., they are two-way interactive). As reported last year, this provided a simulation of the basic features of mesoscale events over the CART site during the period 16-26 June 1993 when an Intensive Observation Period (IOP) was under way.

  5. Validation of mesoscale models

    NASA Technical Reports Server (NTRS)

    Kuo, Bill; Warner, Tom; Benjamin, Stan; Koch, Steve; Staniforth, Andrew

    1993-01-01

    The topics discussed include the following: verification of cloud prediction from the PSU/NCAR mesoscale model; results form MAPS/NGM verification comparisons and MAPS observation sensitivity tests to ACARS and profiler data; systematic errors and mesoscale verification for a mesoscale model; and the COMPARE Project and the CME.

  6. Modeling mesoscale eddies

    NASA Astrophysics Data System (ADS)

    Canuto, V. M.; Dubovikov, M. S.

    Mesoscale eddies are not resolved in coarse resolution ocean models and must be modeled. They affect both mean momentum and scalars. At present, no generally accepted model exists for the former; in the latter case, mesoscales are modeled with a bolus velocity u∗ to represent a sink of mean potential energy. However, comparison of u∗(model) vs. u∗ (eddy resolving code, [J. Phys. Ocean. 29 (1999) 2442]) has shown that u∗(model) is incomplete and that additional terms, "unrelated to thickness source or sinks", are required. Thus far, no form of the additional terms has been suggested. To describe mesoscale eddies, we employ the Navier-Stokes and scalar equations and a turbulence model to treat the non-linear interactions. We then show that the problem reduces to an eigenvalue problem for the mesoscale Bernoulli potential. The solution, which we derive in analytic form, is used to construct the momentum and thickness fluxes. In the latter case, the bolus velocity u∗ is found to contain two types of terms: the first type entails the gradient of the mean potential vorticity and represents a positive contribution to the production of mesoscale potential energy; the second type of terms, which is new, entails the velocity of the mean flow and represents a negative contribution to the production of mesoscale potential energy, or equivalently, a backscatter process whereby a fraction of the mesoscale potential energy is returned to the original reservoir of mean potential energy. This type of terms satisfies the physical description of the additional terms given by [J. Phys. Ocean. 29 (1999) 2442]. The mesoscale flux that enters the momentum equations is also contributed by two types of terms of the same physical nature as those entering the thickness flux. The potential vorticity flux is also shown to contain two types of terms: the first is of the gradient-type while the other terms entail the velocity of the mean flow. An expression is derived for the mesoscale

  7. Acid rain: Mesoscale model

    NASA Technical Reports Server (NTRS)

    Hsu, H. M.

    1980-01-01

    A mesoscale numerical model of the Florida peninsula was formulated and applied to a dry, neutral atmosphere. The prospective use of the STAR-100 computer for the submesoscale model is discussed. The numerical model presented is tested under synoptically undisturbed conditions. Two cases, differing only in the direction of the prevailing geostrophic wind, are examined: a prevailing southwest wind and a prevailing southeast wind, both 6 m/sec at all levels initially.

  8. Mesoscale ocean dynamics modeling

    SciTech Connect

    mHolm, D.; Alber, M.; Bayly, B.; Camassa, R.; Choi, W.; Cockburn, B.; Jones, D.; Lifschitz, A.; Margolin, L.; Marsden, L.; Nadiga, B.; Poje, A.; Smolarkiewicz, P.; Levermore, D.

    1996-05-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The ocean is a very complex nonlinear system that exhibits turbulence on essentially all scales, multiple equilibria, and significant intrinsic variability. Modeling the ocean`s dynamics at mesoscales is of fundamental importance for long-time-scale climate predictions. A major goal of this project has been to coordinate, strengthen, and focus the efforts of applied mathematicians, computer scientists, computational physicists and engineers (at LANL and a consortium of Universities) in a joint effort addressing the issues in mesoscale ocean dynamics. The project combines expertise in the core competencies of high performance computing and theory of complex systems in a new way that has great potential for improving ocean models now running on the Connection Machines CM-200 and CM-5 and on the Cray T3D.

  9. The multiple nesting of mesoscale, submesoscale, and nonhydrostatic microscale numerical models for a case of mesocyclogenesis and severe storm development

    NASA Technical Reports Server (NTRS)

    Kaplan, M. L.; Gooden, A. L.

    1977-01-01

    A fundamental approach involving the integration of two different numerical models over several different spatial mesh lengths is considered. Model I is a hydrostatic, incompressible, and adiabatic primitive (Newtonian) equation set with no boundary layer forcing, i.e., surface heat or moisture flux or external frictional stresses. Typically this model is initialized from conventional radiosonde data and run for a 12-15 hour forecast period over a 40 km horizontal mesh. If phase I of the tornado developmental processes develops, the data is 'frozen' in space and time, interpolated to a 20 km mesh, and integrated for a shorter time period (3 hours) with a shorter time step. Model II is a nonhydrostatic compressible 18-level complement of model I. If model II indicates the development of the intensification of phase V dynamical processes, the data is frozen and interpolated to finer mesh lengths until the tornadic circulation system is approximated

  10. Nesting Large-Eddy Simulations Within Mesoscale Simulations for Wind Energy Applications

    NASA Astrophysics Data System (ADS)

    Lundquist, J. K.; Mirocha, J. D.; Chow, F. K.; Kosovic, B.; Lundquist, K. A.

    2008-12-01

    With increasing demand for more accurate atmospheric simulations for wind turbine micrositing, for operational wind power forecasting, and for more reliable turbine design, simulations of atmospheric flow with resolution of tens of meters or higher are required. These time-dependent large-eddy simulations (LES) account for complex terrain and resolve individual atmospheric eddies on length scales smaller than turbine blades. These small-domain high-resolution simulations are possible with a range of commercial and open- source software, including the Weather Research and Forecasting (WRF) model. In addition to "local" sources of turbulence within an LES domain, changing weather conditions outside the domain can also affect flow, suggesting that a mesoscale model provide boundary conditions to the large-eddy simulations. Nesting a large-eddy simulation within a mesoscale model requires nuanced representations of turbulence. Our group has improved the Weather and Research Forecating model's (WRF) LES capability by implementing the Nonlinear Backscatter and Anisotropy (NBA) subfilter stress model following Kosoviæ (1997) and an explicit filtering and reconstruction technique to compute the Resolvable Subfilter-Scale (RSFS) stresses (following Chow et al, 2005). We have also implemented an immersed boundary method (IBM) in WRF to accommodate complex terrain. These new models improve WRF's LES capabilities over complex terrain and in stable atmospheric conditions. We demonstrate approaches to nesting LES within a mesoscale simulation for farms of wind turbines in hilly regions. Results are sensitive to the nesting method, indicating that care must be taken to provide appropriate boundary conditions, and to allow adequate spin-up of turbulence in the LES domain. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  11. Eddy Effects in the General Circulation, Spanning Mean Currents, Mesoscale Eddies, and Topographic Generation, Including Submesoscale Nests

    DTIC Science & Technology

    2013-09-30

    Eddies, and Topographic Generation, Including Submesoscale Nests Alexander F. Shchepetkin (PI) James C. McWilliams and Maarten J. Molemaker (co-PIs... submesoscale phenomena; analysis and understanding the underlying physical processes; improving parameterizations of unresolved processes...mesoscale and submesoscale eddies generated by instability and bottom topography effects. This is accompanied by development of modeling codes

  12. Saharan Cyclogenesis As Seen From Mesoscale Modeling

    NASA Astrophysics Data System (ADS)

    Born, K.; Simmer, C.

    In order to study causes of longterm rainfall variability in Northwestafrica in the framework of IMPETUS Westafrica, typical rainfall events--extratropical fronts, oro- graphically triggered thunderstorms, advection of moist tropical air--were examined in detail using the Lokalmodell (LM) of the German Weather Service. One of the most interesting types of rainfall bearing phenomena are Saharan cyclones, which form usu- ally in the lee of the Atlas Mountains. They have been subject to some studies in the past, because they may be connected with severe dust storms and strong rainfall even in the dry season. With their relatively small vertical extent, their short lifetime and - in most cases - their absence of a clearly visible cold front, they seem to be typical mesoscale cyclones. Nevertheless, a closer view shows that these cyclones are con- nected with strong inactive synoptic scale cold fronts. Multiscale interactions, i. e. thunderstorms occurring in the warm sector of Saharan cyclones, rapid movement and synoptic scale forcing makes them to interesting objects for mesoscale modelling. The convection parameterization--which has to be adapted to the mesoscale-- as well as the nesting into initial and boundary data are very important for the development of Saharan cyclones in the model environment.

  13. Mesoscale Modeling, Forecasting and Remote Sensing Research.

    DTIC Science & Technology

    remote sensing , cyclonic scale diagnostic studies and mesoscale numerical modeling and forecasting are summarized. Mechanisms involved in the release of potential instability are discussed and simulated quantitatively, giving particular attention to the convective formulation. The basic mesoscale model is documented including the equations, boundary condition, finite differences and initialization through an idealized frontal zone. Results of tests including a three dimensional test with real data, tests of convective/mesoscale interaction and tests with a detailed

  14. Mesoscale Wind Predictions for Wave Model Evaluation

    DTIC Science & Technology

    2016-06-07

    SEP 1999 2. REPORT TYPE 3. DATES COVERED 00-00-1999 to 00-00-1999 4. TITLE AND SUBTITLE Mesoscale Wind Predictions for Wave Model Evaluation...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 1 Mesoscale Wind Predictions for Wave Model...resolution (< 10 km) atmospheric wind and surface stress fields produced by an atmospheric mesoscale data assimilation system to the numerical prediction of

  15. Wind turbine parameterizations implemented in WRF mesoscale-LES nested simulations

    NASA Astrophysics Data System (ADS)

    Marjanovic, N.; Mirocha, J. D.; Chow, F. K.

    2014-12-01

    Atmospheric simulations can be used to predict wind energy production at increasingly higher resolutions, which can better capture boundary layer processes and topography. Wind turbine performance depends on several different factors including local topography, weather conditions, and turbine spacing. In this work, we implement and examine the performance of a generalized actuator disk model (GAD) and a generalized actuator line model (GAL) in the Weather Research and Forecasting (WRF) model, a mesoscale atmospheric model. The wind turbine parameterizations are designed for turbulence-resolving simulations, and are used within downscaled large-eddy simulations (LES) forced with mesoscale simulations and WRF's grid nesting capability. The GAD represents the effects of thrust and torque created by a wind turbine on the atmosphere within a disk representing the rotor swept area. The forces applied by the turbine blades on the atmosphere are parameterized using blade-element theory and the aerodynamic properties of the blades. The GAL tracks the location of the individual turbine blades and applies thrust and tangential forces at the temporal location of each blade instead of distributing the total force of all the blades over the actuator disk like the GAD does. This should in theory increase fidelity but carries higher computational cost (~10 m for GAD vs. ~1 m resolution for GAL). Both GAD and GAL models include real-time yaw and pitch control to respond realistically to changing flow conditions. Comparisons are also made to help determine the importance of turbine blade tilt away from the tower and the inclusion of the tower and turbine hub drag effects. Our implementations are designed to permit simulation of turbine wake effects and turbine/airflow interactions within a realistic atmospheric boundary layer flow field, including resolved turbulence, time-evolving mesoscale forcing, and real topography. This work was performed under the auspices of the U

  16. Mesoscale acid deposition modeling studies

    NASA Technical Reports Server (NTRS)

    Kaplan, Michael L.; Proctor, F. H.; Zack, John W.; Karyampudi, V. Mohan; Price, P. E.; Bousquet, M. D.; Coats, G. D.

    1989-01-01

    The work performed in support of the EPA/DOE MADS (Mesoscale Acid Deposition) Project included the development of meteorological data bases for the initialization of chemistry models, the testing and implementation of new planetary boundary layer parameterization schemes in the MASS model, the simulation of transport and precipitation for MADS case studies employing the MASS model, and the use of the TASS model in the simulation of cloud statistics and the complex transport of conservative tracers within simulated cumuloform clouds. The work performed in support of the NASA/FAA Wind Shear Program included the use of the TASS model in the simulation of the dynamical processes within convective cloud systems, the analyses of the sensitivity of microburst intensity and general characteristics as a function of the atmospheric environment within which they are formed, comparisons of TASS model microburst simulation results to observed data sets, and the generation of simulated wind shear data bases for use by the aviation meteorological community in the evaluation of flight hazards caused by microbursts.

  17. Dynamic Model of Mesoscale Eddies

    NASA Astrophysics Data System (ADS)

    Dubovikov, Mikhail S.

    2003-04-01

    Oceanic mesoscale eddies which are analogs of well known synoptic eddies (cyclones and anticyclones), are studied on the basis of the turbulence model originated by Dubovikov (Dubovikov, M.S., "Dynamical model of turbulent eddies", Int. J. Mod. Phys.B7, 4631-4645 (1993).) and further developed by Canuto and Dubovikov (Canuto, V.M. and Dubovikov, M.S., "A dynamical model for turbulence: I. General formalism", Phys. Fluids8, 571-586 (1996a) (CD96a); Canuto, V.M. and Dubovikov, M.S., "A dynamical model for turbulence: II. Sheardriven flows", Phys. Fluids8, 587-598 (1996b) (CD96b); Canuto, V.M., Dubovikov, M.S., Cheng, Y. and Dienstfrey, A., "A dynamical model for turbulence: III. Numerical results", Phys. Fluids8, 599-613 (1996c)(CD96c); Canuto, V.M., Dubovikov, M.S. and Dienstfrey, A., "A dynamical model for turbulence: IV. Buoyancy-driven flows", Phys. Fluids9, 2118-2131 (1997a) (CD97a); Canuto, V.M. and Dubovikov, M.S., "A dynamical model for turbulence: V. The effect of rotation", Phys. Fluids9, 2132-2140 (1997b) (CD97b); Canuto, V.M., Dubovikov, M.S. and Wielaard, D.J., "A dynamical model for turbulence: VI. Two dimensional turbulence", Phys. Fluids9, 2141-2147 (1997c) (CD97c); Canuto, V.M. and Dubovikov, M.S., "Physical regimes and dimensional structure of rotating turbulence", Phys. Rev. Lett. 78, 666-669 (1997d) (CD97d); Canuto, V.M., Dubovikov, M.S. and Dienstfrey, A., "Turbulent convection in a spectral model", Phys. Rev. Lett. 78, 662-665 (1997e) (CD97e); Canuto, V.M. and Dubovikov, M.S., "A new approach to turbulence", Int. J. Mod. Phys.12, 3121-3152 (1997f) (CD97f); Canuto, V.M. and Dubovikov, M.S., "Two scaling regimes for rotating Raleigh-Benard convection", Phys. Rev. Letters78, 281-284, (1998) (CD98); Canuto, V.M. and Dubovikov, M.S., "A dynamical model for turbulence: VII. The five invariants for shear driven flows", Phys. Fluids11, 659-664 (1999a) (CD99a); Canuto, V.M., Dubovikov, M.S. and Yu, G., "A dynamical model for turbulence: VIII. IR and UV

  18. Chemistry on the mesoscale: Modeling and measurement issues

    NASA Technical Reports Server (NTRS)

    Thompson, Anne; Pleim, John; Walcek, Christopher; Ching, Jason; Binkowski, Frank; Tao, Wei-Kuo; Dickerson, Russell; Pickering, Kenneth

    1993-01-01

    The topics covered include the following: Regional Acid Deposition Model (RADM) -- a coupled chemistry/mesoscale model; convection in RADM; unresolved issues for mesoscale modeling with chemistry -- nonprecipitating clouds; unresolved issues for mesoscale modeling with chemistry -- aerosols; tracer studies with Goddard Cumulus Ensemble Model (GCEM); field observations of trace gas transport in convection; and photochemical consequences of convection.

  19. Mesoscale Modeling of Energetic Materials

    DTIC Science & Technology

    2014-10-23

    This briefing represents interim progress towards these goals. 15. SUBJECT TERMS Heterogeneous explosives , Mesoscale dynamics, Level set method...High  Explosives  Research and Development Branch (RWME) – Damage Mechanisms Branch (RWMW) • Goal: Predict survivability of energetic payload of high...the mechanical  behavior of simple  explosive – Pristine – Damaged • Performed simulations on mechanical RVE’s – From XCMT – Idealized • Developed and

  20. Nano- and mesoscale modeling of cement matrix

    NASA Astrophysics Data System (ADS)

    Yu, Zechuan; Lau, Denvid

    2015-04-01

    Atomistic simulations of cementitious material can enrich our understanding of its structural and mechanical properties, whereas current computational capacities restrict the investigation length scale within 10 nm. In this context, coarse-grained simulations can translate the information from nanoscale to mesoscale, thus bridging the multi-scale investigations. Here, we develop a coarse-grained model of cement matrix using the concept of disk-like building block. The objective is to introduce a new method to construct a coarse-grained model of cement, which could contribute to the scale-bridging issue from nanoscale to mesoscale. PAC codes: 07.05.Tp, 62.25.-g, 82.70.Dd

  1. Nano- and mesoscale modeling of cement matrix.

    PubMed

    Yu, Zechuan; Lau, Denvid

    2015-01-01

    Atomistic simulations of cementitious material can enrich our understanding of its structural and mechanical properties, whereas current computational capacities restrict the investigation length scale within 10 nm. In this context, coarse-grained simulations can translate the information from nanoscale to mesoscale, thus bridging the multi-scale investigations. Here, we develop a coarse-grained model of cement matrix using the concept of disk-like building block. The objective is to introduce a new method to construct a coarse-grained model of cement, which could contribute to the scale-bridging issue from nanoscale to mesoscale. PAC codes: 07.05.Tp, 62.25.-g, 82.70.Dd.

  2. Modeling mesoscale circulation of the Black Sea

    NASA Astrophysics Data System (ADS)

    Korotenko, K. A.

    2015-11-01

    An eddy-resolving (1/30)° version of the DieCAST low-dissipative model, adapted to the Black Sea circulation, is presented. Under mean climatological forcing, the model realistically reproduces major dominant large-scale and mesoscale structures of seasonal sea circulation, including the Rim Current, coastal anticyclonic eddies, mushroom currents, etc. Due to its extremely low dissipation and high resolution, the model makes it possible to trace the development of the baroclinic instability along the Turkish and Caucasian coasts, reproduce mesoscale structures generated by this mechanism, and assess the scales of these structures. The model also realistically reproduces short-term effects of bora winds on the evolution of subsurface layer structures.

  3. Mesoscale model forecast verification during monsoon 2008

    NASA Astrophysics Data System (ADS)

    Ashrit, Raghavendra; Mohandas, Saji

    2010-08-01

    There have been very few mesoscale modelling studies of the Indian monsoon, with focus on the verification and intercomparison of the operational real time forecasts. With the exception of Das et al (2008), most of the studies in the literature are either the case studies of tropical cyclones and thunderstorms or the sensitivity studies involving physical parameterization or climate simulation studies. Almost all the studies are based on either National Center for Environmental Prediction (NCEP), USA, final analysis fields (NCEP FNL) or the reanalysis data used as initial and lateral boundary conditions for driving the mesoscale model. Here we present a mesoscale model forecast verification and intercomparison study over India involving three mesoscale models: (i) the Weather Research and Forecast (WRF) model developed at the National Center for Atmospheric Research (NCAR), USA, (ii) the MM5 model developed by NCAR, and (iii) the Eta model of the NCEP, USA. The analysis is carried out for the monsoon season, June to September 2008. This study is unique since it is based entirely on the real time global model forecasts of the National Centre for Medium Range Weather Forecasting (NCMRWF) T254 global analysis and forecast system. Based on the evaluation and intercomparison of the mesoscale model forecasts, we recommend the best model for operational real-time forecasts over the Indian region. Although the forecast mean 850 hPa circulation shows realistic monsoon flow and the monsoon trough, the systematic errors over the Arabian Sea indicate an easterly bias to the north (of mean flow) and westerly bias to the south (of mean flow). This suggests that the forecasts feature a southward shift in the monsoon current. The systematic error in the 850 hPa temperature indicates that largely the WRF model forecasts feature warm bias and the MM5 model forecasts feature cold bias. Features common to all the three models include warm bias over northwest India and cold bias over

  4. Mesoscale Modeling of Chromatin Folding

    NASA Astrophysics Data System (ADS)

    Schlick, Tamar

    2009-03-01

    Eukaryotic chromatin is the fundamental protein/nucleic acid unit that stores the genetic material. Understanding how chromatin fibers fold and unfold in physiological conditions is important for interpreting fundamental biological processes like DNA replication and transcription regulation. Using a mesoscopic model of oligonucleosome chains and tailored sampling protocols, we elucidate the energetics of oligonucleosome folding/unfolding and the role of each histone tail, linker histones, and divalent ions in regulating chromatin structure. The resulting compact topologies reconcile features of the zigzag model with straight linker DNAs with the solenoid model with bent linker DNAs for optimal fiber organization and reveal dynamic and energetic aspects involved.

  5. A new vertical grid nesting capability in the Weather Research and Forecasting (WRF) Model

    DOE PAGES

    Daniels, Megan H.; Lundquist, Katherine A.; Mirocha, Jeffrey D.; ...

    2016-09-16

    Mesoscale atmospheric models are increasingly used for high-resolution (<3 km) simulations to better resolve smaller-scale flow details. Increased resolution is achieved using mesh refinement via grid nesting, a procedure where multiple computational domains are integrated either concurrently or in series. A constraint in the concurrent nesting framework offered by the Weather Research and Forecasting (WRF) Model is that mesh refinement is restricted to the horizontal dimensions. This limitation prevents control of the grid aspect ratio, leading to numerical errors due to poor grid quality and preventing grid optimization. Here, a procedure permitting vertical nesting for one-way concurrent simulation is developedmore » and validated through idealized cases. The benefits of vertical nesting are demonstrated using both mesoscale and large-eddy simulations (LES). Mesoscale simulations of the Terrain-Induced Rotor Experiment (T-REX) show that vertical grid nesting can alleviate numerical errors due to large aspect ratios on coarse grids, while allowing for higher vertical resolution on fine grids. Furthermore, the coarsening of the parent domain does not result in a significant loss of accuracy on the nested domain. LES of neutral boundary layer flow shows that, by permitting optimal grid aspect ratios on both parent and nested domains, use of vertical nesting yields improved agreement with the theoretical logarithmic velocity profile on both domains. Lastly, vertical grid nesting in WRF opens the path forward for multiscale simulations, allowing more accurate simulations spanning a wider range of scales than previously possible.« less

  6. A new vertical grid nesting capability in the Weather Research and Forecasting (WRF) Model

    SciTech Connect

    Daniels, Megan H.; Lundquist, Katherine A.; Mirocha, Jeffrey D.; Wiersema, David J.; Chow, Fotini K.

    2016-09-16

    Mesoscale atmospheric models are increasingly used for high-resolution (<3 km) simulations to better resolve smaller-scale flow details. Increased resolution is achieved using mesh refinement via grid nesting, a procedure where multiple computational domains are integrated either concurrently or in series. A constraint in the concurrent nesting framework offered by the Weather Research and Forecasting (WRF) Model is that mesh refinement is restricted to the horizontal dimensions. This limitation prevents control of the grid aspect ratio, leading to numerical errors due to poor grid quality and preventing grid optimization. Here, a procedure permitting vertical nesting for one-way concurrent simulation is developed and validated through idealized cases. The benefits of vertical nesting are demonstrated using both mesoscale and large-eddy simulations (LES). Mesoscale simulations of the Terrain-Induced Rotor Experiment (T-REX) show that vertical grid nesting can alleviate numerical errors due to large aspect ratios on coarse grids, while allowing for higher vertical resolution on fine grids. Furthermore, the coarsening of the parent domain does not result in a significant loss of accuracy on the nested domain. LES of neutral boundary layer flow shows that, by permitting optimal grid aspect ratios on both parent and nested domains, use of vertical nesting yields improved agreement with the theoretical logarithmic velocity profile on both domains. Lastly, vertical grid nesting in WRF opens the path forward for multiscale simulations, allowing more accurate simulations spanning a wider range of scales than previously possible.

  7. An Overview of Mesoscale Modeling Software for Energetic Materials Research

    DTIC Science & Technology

    2010-03-01

    areas of primary interest with regard to mesoscale modeling software are: • Soft materials, such as polymers , melts, blends, surfactants, complex...materials: Processing of materials requires an understanding of how polycrystalline materials interact with polymer binders. Mesoscale modeling...Mesocale modeling software summary. Software Algorithms Applications/Properties MesoDyn Dynamic Density Field Soft matter, polymers , melts, blends

  8. Probabilistic, meso-scale flood loss modelling

    NASA Astrophysics Data System (ADS)

    Kreibich, Heidi; Botto, Anna; Schröter, Kai; Merz, Bruno

    2016-04-01

    Flood risk analyses are an important basis for decisions on flood risk management and adaptation. However, such analyses are associated with significant uncertainty, even more if changes in risk due to global change are expected. Although uncertainty analysis and probabilistic approaches have received increased attention during the last years, they are still not standard practice for flood risk assessments and even more for flood loss modelling. State of the art in flood loss modelling is still the use of simple, deterministic approaches like stage-damage functions. Novel probabilistic, multi-variate flood loss models have been developed and validated on the micro-scale using a data-mining approach, namely bagging decision trees (Merz et al. 2013). In this presentation we demonstrate and evaluate the upscaling of the approach to the meso-scale, namely on the basis of land-use units. The model is applied in 19 municipalities which were affected during the 2002 flood by the River Mulde in Saxony, Germany (Botto et al. submitted). The application of bagging decision tree based loss models provide a probability distribution of estimated loss per municipality. Validation is undertaken on the one hand via a comparison with eight deterministic loss models including stage-damage functions as well as multi-variate models. On the other hand the results are compared with official loss data provided by the Saxon Relief Bank (SAB). The results show, that uncertainties of loss estimation remain high. Thus, the significant advantage of this probabilistic flood loss estimation approach is that it inherently provides quantitative information about the uncertainty of the prediction. References: Merz, B.; Kreibich, H.; Lall, U. (2013): Multi-variate flood damage assessment: a tree-based data-mining approach. NHESS, 13(1), 53-64. Botto A, Kreibich H, Merz B, Schröter K (submitted) Probabilistic, multi-variable flood loss modelling on the meso-scale with BT-FLEMO. Risk Analysis.

  9. Nested Gulf of Mexico Modeling with HYCOM

    DTIC Science & Technology

    2004-10-29

    Gulf of Mexico Modeling with HYCOM Patrick J. Hogan1 Alan J. Wallcraft1 Ole Martin Smedstad2 1Naval Research Laboratory Stennis Space Center...2004 4. TITLE AND SUBTITLE Nested Gulf of Mexico Modeling with HYCOM 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Running Nested Gulf of Mexico • 1/12° Assimilative Nested Gulf of Mexico 1/25° Free-Running Nested Gulf of Mexico

  10. Mesoscale Modelling of the Response of Aluminas

    SciTech Connect

    Bourne, N. K.

    2006-07-28

    The response of polycrystalline alumina to shock is not well addressed. There are several operating mechanisms that only hypothesized which results in models which are empirical. A similar state of affairs in reactive flow modelling led to the development of mesoscale representations of the flow to illuminate operating mechanisms. In this spirit, a similar effort is undergone for a polycrystalline alumina. Simulations are conducted to observe operating mechanisms at the micron scale. A method is then developed to extend the simulations to meet response at the continuum level where measurements are made. The approach is validated by comparison with continuum experiments. The method and results are presented, and some of the operating mechanisms are illuminated by the observed response.

  11. Real-Time Mesoscale Modeling Over Antarctica: The Antarctic Mesoscale Prediction System*.

    NASA Astrophysics Data System (ADS)

    Powers, Jordan G.; Monaghan, Andrew J.; Cayette, Arthur M.; Bromwich, David H.; Kuo, Ying-Hwa; Manning, Kevin W.

    2003-11-01

    *Byrd Polar Research Center Contribution Number 1276In support of the United States Antarctic Program (USAP), the National Center for Atmospheric Research and the Byrd Polar Research Center of The Ohio State University have created the Antarctic Mesoscale Prediction System (AMPS): an experimental, real-time mesoscale modeling system covering Antarctica. AMPS has been designed to serve flight forecasters at McMurdo Station, to support science and operations around the continent, and to be a vehicle for the development of physical parameterizations suitable for polar regions. Since 2000, AMPS has been producing high-resolution forecasts (grids to 3.3 km) with the “Polar MM5,” a version of the fifth-generation Pennsylvania State University NCAR Mesoscale Model tuned for the polar atmosphere. Beyond its basic mission of serving the USAP flight forecasters at McMurdo, AMPS has assisted both in emergency operations to save lives and in programs to explore the extreme polar environment. The former have included a medical evacuation from the South Pole and a marine rescue from the continental margin. The latter have included scientific field campaigns and the daily activities of international Antarctic forecasters and researchers. The AMPS program has been a success in terms of advancing polar mesoscale NWP, serving critical logistical operations of the USAP, and, most visibly, assisting in emergency rescue missions to save lives. The history and performance of AMPS are described and the successes of this unique real-time mesoscale modeling system in crisis support are detailed.

  12. Meso-NH: Non-hydrostatic mesoscale atmospheric model

    NASA Astrophysics Data System (ADS)

    Laboratoire d'Aérologie; Centre National de Recherches Météorologiques

    2016-12-01

    Meso-NH is the non-hydrostatic mesoscale atmospheric model of the French research community 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 model SURFEX for representation of surface atmosphere 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 model output directly with satellite observations, radar, lidar and GPS.

  13. User's guide to the Penn State/NCAR Mesoscale Modeling System

    NASA Astrophysics Data System (ADS)

    Gill, David O.

    1992-10-01

    An updated version of the Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Modeling system (the MM4 system) is presented. The standard MM4 modeling package employs a Cressman multi-scan isobaric and surface analysis, with a hydrostatic predictive component using a leap frog integration of the flux form of the primitive equations on sigma coordinates. An experimental version has expanded the data ingest routines to allow hybrid isentropic-isobaric + surface analyses. Experimental versions of the model allow split-explicit time integration, several cumulus parameterizations coupled with an explicit moisture scheme, multiple levels of movable nests, relaxation of the hydrostatic assumptions, additional planetary boundary layer schemes, and microphysical packages. Due to the developmental nature of the modeling system, periodic upgrades in documentation are required to keep the manuals in accord with the programs. The document supersedes Penn State/NCAR Mesoscale Model User's Manual--Ver 8.

  14. Evaluation of Mesoscale Model Phenomenological Verification Techniques

    NASA Technical Reports Server (NTRS)

    Lambert, Winifred

    2006-01-01

    Forecasters at the Spaceflight Meteorology Group, 45th Weather Squadron, and National Weather Service in Melbourne, FL use mesoscale numerical weather prediction model output in creating their operational forecasts. These models aid in forecasting weather phenomena that could compromise the safety of launch, landing, and daily ground operations and must produce reasonable weather forecasts in order for their output to be useful in operations. Considering the importance of model forecasts to operations, their accuracy in forecasting critical weather phenomena must be verified to determine their usefulness. The currently-used traditional verification techniques involve an objective point-by-point comparison of model output and observations valid at the same time and location. The resulting statistics can unfairly penalize high-resolution models that make realistic forecasts of a certain phenomena, but are offset from the observations in small time and/or space increments. Manual subjective verification can provide a more valid representation of model performance, but is time-consuming and prone to personal biases. An objective technique that verifies specific meteorological phenomena, much in the way a human would in a subjective evaluation, would likely produce a more realistic assessment of model performance. Such techniques are being developed in the research community. The Applied Meteorology Unit (AMU) was tasked to conduct a literature search to identify phenomenological verification techniques being developed, determine if any are ready to use operationally, and outline the steps needed to implement any operationally-ready techniques into the Advanced Weather Information Processing System (AWIPS). The AMU conducted a search of all literature on the topic of phenomenological-based mesoscale model verification techniques and found 10 different techniques in various stages of development. Six of the techniques were developed to verify precipitation forecasts, one

  15. Meso-Scale Modeling of Polycrystal Deformation

    NASA Astrophysics Data System (ADS)

    Lim, Hojun

    Computational material modeling of material is essential to accelerate material/process design and reduce costs in wide variety of applications. In particular, multi-scale models are gaining momentum in many fields as computers become faster, and finer structures become accessible experimentally. An effective (i.e. sufficiently accurate and fast to have practical impact) multi-scale model of dislocation-based metal plasticity may have many important applications such as metal forming. A two-scale method to predict quantitatively the Hall-Petch effect, as well as dislocation densities and lattice curvatures throughout a polycrystal, has been developed and implemented. Based on a finite element formulation, the first scale is called a Grain-Scale Simulation (GSS) that is standard except for using novel single-crystal constitutive equations that were proposed and tested as part of this work (and which are informed from the second model scale). The GSS allows the determination of local stresses, strains, and slip magnitudes while enforcing compatibility and equilibrium throughout a polycrystal in a finite element sense. The second scale is called here a Meso-Scale Simulation (MSS) which is novel in concept and application. It redistributes the mobile part of the dislocation density within grains consistent with the plastic strain distribution, and enforces slip transmission criteria at grain boundaries that depend on local grain and boundary properties. Stepwise simulation at the two scales proceeds sequentially in order to predict the spatial distribution of dislocation density and the flow stress for each slip system within each grain, and each simulation point. The MSS was formulated with the minimum number of undermined or arbitrary parameters, three. Two of these are related to the shape of the strain hardening curve and the other represents the initial yield. These parameters do not invoke additional length scales. The new model made possible the following

  16. Nested ocean models: Work in progress

    NASA Technical Reports Server (NTRS)

    Perkins, A. Louise

    1991-01-01

    The ongoing work of combining three existing software programs into a nested grid oceanography model is detailed. The HYPER domain decomposition program, the SPEM ocean modeling program, and a quasi-geostrophic model written in England are being combined into a general ocean modeling facility. This facility will be used to test the viability and the capability of two-way nested grids in the North Atlantic.

  17. An evaluation of the synoptic- and mesoscale predictability of the Mesoscale Atmospheric Simulation System (MASS 2.0) model

    NASA Technical Reports Server (NTRS)

    Koch, S. E.; Skillman, W. C.; Kocin, P. J.; Wetzel, P. J.; Brill, K. F.

    1983-01-01

    A report is presented regarding the synoptic- and mesoscale predictive capabilities of a regional-scale numerical weather prediction model known as the Mesoscale Atmospheric Simulation System (MASS, Version 2.0). The development of this model has been discussed by Kaplan et al. (1982). An evaluation of the performance of MASS 2.0 is based on the study of a sample of approximately thirty 12 h and 24 h forecasts of atmospheric flow patterns over the U.S. during spring and early summer of 1982. A description of model systems is provided, and synoptic-scale evaluation methods are considered along with aspects of mesoscale evaluation methodology, examples of coherent mesoscale information provided by MASS 2.0, the results of a diagnostic study of mesoscale convective systems (MCS), and the results of a limited real-time forecast experiment.

  18. Nested Gulf of Mexico Modeling with HYCOM

    DTIC Science & Technology

    2005-12-08

    Nested Gulf of Mexico Modeling with HYCOM Patrick J. Hogan Alan J. Wallcraft Naval Research Laboratory Stennis Space Center, MS HYCOM Meeting...valid OMB control number. 1. REPORT DATE DEC 2005 2. REPORT TYPE 3. DATES COVERED 00-00-2005 to 00-00-2005 4. TITLE AND SUBTITLE Nested Gulf of Mexico Modeling...topography is from NRL-DBDB2 • Integrated over 2000-2001 1/25° (~4 km) non-assimilative Nested Gulf of Mexico Possible cross-shelf transport

  19. Recent Applications of Mesoscale Modeling to Nanotechnology and Drug Delivery

    SciTech Connect

    Maiti, A; Wescott, J; Kung, P; Goldbeck-Wood, G

    2005-02-11

    Mesoscale simulations have traditionally been used to investigate structural morphology of polymer in solution, melts and blends. Recently we have been pushing such modeling methods to important areas of Nanotechnology and Drug delivery that are well out of reach of classical molecular dynamics. This paper summarizes our efforts in three important emerging areas: (1) polymer-nanotube composites; (2) drug diffusivity through cell membranes; and (3) solvent exchange in nanoporous membranes. The first two applications are based on a bead-spring-based approach as encoded in the Dissipative Particle Dynamics (DPD) module. The last application used density-based Mesoscale modeling as implemented in the Mesodyn module.

  20. Mesoscale to microscale wind farm flow modeling and evaluation: Mesoscale to Microscale Wind Farm Models

    SciTech Connect

    Sanz Rodrigo, Javier; Chávez Arroyo, Roberto Aurelio; Moriarty, Patrick; Churchfield, Matthew; Kosović, Branko; Réthoré, Pierre-Elouan; Hansen, Kurt Schaldemose; Hahmann, Andrea; Mirocha, Jeffrey D.; Rife, Daran

    2016-08-31

    The increasing size of wind turbines, with rotors already spanning more than 150 m diameter and hub heights above 100 m, requires proper modeling of the atmospheric boundary layer (ABL) from the surface to the free atmosphere. Furthermore, large wind farm arrays create their own boundary layer structure with unique physics. This poses significant challenges to traditional wind engineering models that rely on surface-layer theories and engineering wind farm models to simulate the flow in and around wind farms. However, adopting an ABL approach offers the opportunity to better integrate wind farm design tools and meteorological models. The challenge is how to build the bridge between atmospheric and wind engineering model communities and how to establish a comprehensive evaluation process that identifies relevant physical phenomena for wind energy applications with modeling and experimental requirements. A framework for model verification, validation, and uncertainty quantification is established to guide this process by a systematic evaluation of the modeling system at increasing levels of complexity. In terms of atmospheric physics, 'building the bridge' means developing models for the so-called 'terra incognita,' a term used to designate the turbulent scales that transition from mesoscale to microscale. This range of scales within atmospheric research deals with the transition from parameterized to resolved turbulence and the improvement of surface boundary-layer parameterizations. The coupling of meteorological and wind engineering flow models and the definition of a formal model evaluation methodology, is a strong area of research for the next generation of wind conditions assessment and wind farm and wind turbine design tools. Some fundamental challenges are identified in order to guide future research in this area.

  1. Mesoscale modeling of solute precipitation and radiation damage

    SciTech Connect

    Zhang, Yongfeng; Schwen, Daniel; Ke, Huibin; Bai, Xianming; Hales, Jason

    2015-09-01

    This report summarizes the low length scale effort during FY 2014 in developing mesoscale capabilities for microstructure evolution in reactor pressure vessels. During operation, reactor pressure vessels are subject to hardening and embrittlement caused by irradiation-induced defect accumulation and irradiation-enhanced solute precipitation. Both defect production and solute precipitation start from the atomic scale, and manifest their eventual effects as degradation in engineering-scale properties. To predict the property degradation, multiscale modeling and simulation are needed to deal with the microstructure evolution, and to link the microstructure feature to material properties. In this report, the development of mesoscale capabilities for defect accumulation and solute precipitation are summarized. Atomic-scale efforts that supply information for the mesoscale capabilities are also included.

  2. Mesoscale modeling of molecular machines: cyclic dynamics and hydrodynamical fluctuations.

    PubMed

    Cressman, Andrew; Togashi, Yuichi; Mikhailov, Alexander S; Kapral, Raymond

    2008-05-01

    Proteins acting as molecular machines can undergo cyclic internal conformational motions that are coupled to ligand binding and dissociation events. In contrast to their macroscopic counterparts, nanomachines operate in a highly fluctuating environment, which influences their operation. To bridge the gap between detailed microscopic and simple phenomenological descriptions, a mesoscale approach, which combines an elastic network model of a machine with a particle-based mesoscale description of the solvent, is employed. The time scale of the cyclic hinge motions of the machine prototype is strongly affected by hydrodynamical coupling to the solvent.

  3. Refinement of a mesoscale model for large eddy simulation

    NASA Astrophysics Data System (ADS)

    Gasset, Nicolas

    With the advent of wind energy technology, several methods have become mature and are seen today as standard for predicting and forecasting the wind. However, their results are still site dependent, and the increasing sizes of both modern wind turbines and wind farms tackle limits of existing methods. Some triggered processes extend to the junction between microscales and mesoscales.The main objectives of this thesis are thus to identify, implement and evaluate an approach allowing for microscale and mesoscale ABL flow modelling considering the various challenges of modern wind energy applications. A literature review of ABL flow modelling from microscales to mesoscales first provides an overview of the specificities and abilities of existing methods. The combined mesoscale/large eddy simulation (LES) modelling appears to be the most promising approach, and the Compressible Community Mesoscale Model (MC2) is elected as the basis of the method in which the components required for LES are added and implemented. A detailed description of the mathematical model and the numerical aspects of the various components of the LES-capable MC2 are then presented so that a complete view of the proposed approach along with the specificities of its implementation are provided. This further allows to introduce the enhancements and new components of the method (separation of volumetric and deviatoric Reynolds tensor terms, vertical staggering, subgrid scale models, 3D turbulent diffusion, 3D turbulent kinetic energy equation), as well as the adaptation of its operating mode to allow for LES (initialization, large scale geostrophic forcing, surface and lateral boundaries). Finally, fundamental aspects and new components of the proposed approach are evaluated based on theoretical 1D Ekman boundary layer and 3D unsteady shear and buoyancy driven homogeneous surface full ABL cases. The model behaviour at high resolution as well as the components required for LES in MC2 are all finely

  4. Runtime system library for parallel finite difference models with nesting

    SciTech Connect

    Michalakes, J.

    1997-03-01

    RSL is a parallel run-time system library for implementing regular-grid models with nesting on distributed memory parallel computers. RSL provides support for automatically decomposing multiple model domains and for redistributing work between processors at run time for dynamic load balancing. A unique feature of RSL is that processor subdomains need not be rectangular patches; rather, grid points are independently allocated to processors, allowing more precisely balanced allocation of work to processors. Communication mechanisms are tailored to the application: RSL provides an efficient high-level stencil exchange operation for updating subdomain ghost areas and interdomain communication to support two-way interaction between nest levels. RSL also provides run-time support for local iteration over subdomains, global-local index translation, and distributed I/O from ordinary Fortran record-blocked data sets. The interface to RSL supports Fortran77 and Fortran90. RSL has been used to parallelize the NCAR/Penn State Mesoscale Model (MM5).

  5. Parameterization of Cumulus Convective Cloud Systems in Mesoscale Forecast Models

    DTIC Science & Technology

    2013-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Parameterization of Cumulus Convective Cloud Systems in...parameterization of cumulus convective clouds in mesoscale numerical weather prediction models OBJECTIVES Conduct detailed studies of cloud ...microphysical processes in order to develop a unified parameterization of boundary layer stratocumulus and trade wind cumulus convective clouds . Develop

  6. Comments on the challenge of using mesoscale data in mesoscale numerical models

    NASA Technical Reports Server (NTRS)

    Uccellini, Louis W.

    1987-01-01

    The dangers of addressing the initialization issues for limited-area mesoscale models by extending the lessons learned during the development of global analysis and prediction systems are discussed. Lack of impact with data inserts at one time suggests that the lateral boundary conditions imposed on the limited-area models might force the model simulation toward a preferred solution, work against the new data being inserted into the model and, therefore, limit the potential impact that this data can have on the model system. The second potential pitfall involves the imposition of balance constraints on the data that are being inserted into the model to compute winds from temperature data and/or temperature from wind data.

  7. Numerical Model Studies of the Martian Mesoscale Circulations

    NASA Technical Reports Server (NTRS)

    Segal, Moti; Arritt, Raymond W.

    1997-01-01

    The study objectives were to evaluate by numerical modeling various possible mesoscale circulation on Mars and related atmospheric boundary layer processes. The study was in collaboration with J. Tillman of the University of Washington (who supported the study observationally). Interaction has been made with J. Prusa of Iowa State University in numerical modeling investigation of dynamical effects of topographically-influenced flow. Modeling simulations included evaluations of surface physical characteristics on: (i) the Martian atmospheric boundary layer and (ii) their impact on thermally and dynamically forced mesoscale flows. Special model evaluations were made in support of selection of the Pathfinder landing sites. J. Tillman's finding of VL-2 inter-annual temperature difference was followed by model simulations attempting to point out the forcing for this feature. Publication of the results in the reviewed literature in pending upon completion of the manuscripts in preparation as indicated later.

  8. Estimation of Eddy Dissipation Rates from Mesoscale Model Simulations

    NASA Technical Reports Server (NTRS)

    Ahmad, Nashat N.; Proctor, Fred H.

    2012-01-01

    The Eddy Dissipation Rate is an important metric for representing the intensity of atmospheric turbulence and is used as an input parameter for predicting the decay of aircraft wake vortices. In this study, the forecasts of eddy dissipation rates obtained from the current state-of-the-art mesoscale model are evaluated for terminal area applications. The Weather Research and Forecast mesoscale model is used to simulate the planetary boundary layer at high horizontal and vertical mesh resolutions. The Bougeault-Lacarrer and the Mellor-Yamada-Janji schemes implemented in the Weather Research and Forecast model are evaluated against data collected during the National Aeronautics and Space Administration s Memphis Wake Vortex Field Experiment. Comparisons with other observations are included as well.

  9. Modeling the mesoscale variability in the Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Korotenko, K. A.

    2007-06-01

    A new high-resolution (<2 km) version of the DieCAST fourth-accuracy-order model for the ocean circulation is proposed for the study of the general circulation, mesoscale structures, and their variability in the Adriatic Sea. The model uses mean seasonal data on the temperature, salinity, buoyancy fluxes, and wind. The data of the COAMPS system with a 4-km resolution were used for the simulation of the sea response to the effects of various winds: Sirocco, Maestro, and two types of boras. The mean monthly runoffs from 38 rivers and mean daily runoffs from 12 main rivers throughout the year were given in the model. The conditions at the open boundary of the Strait of Otranto were given on the basis of the hierarchy of two coarser models for the Adriatic and Mediterranean seas. Due to the extremely weak dissipation and the high resolution (the mesh size is less than the baroclinic radius of deformation, 5 10 km), the model allows one to trace the development of a baroclinic instability along the Italian coast, to simulate mesoscale structures associated with the instability, and to estimate the scales of the structures. Mesoscale filaments, meanders, mushroom-like currents, fronts, and intrusions known from satellite observations were simulated and explained. The scenario of the anomalous upwelling near the Italian coast observed in the summer of 2003 was also simulated and analyzed.

  10. Mesoscale modeling of metal-loaded high explosives

    SciTech Connect

    Bdzil, John Bohdan; Lieberthal, Brandon; Srewart, Donald S

    2010-01-01

    We describe a 3D approach to modeling multi-phase blast explosive, which is primarily condensed explosive by volume with inert embedded particles. These embedded particles are uniform in size and placed on the array of a regular lattice. The asymptotic theory of detonation shock dynamics governs the detonation shock propagation in the explosive. Mesoscale hydrodynamic simulations are used to show how the particles are compressed, deformed, and accelerated by the high-speed detonation products flow.

  11. Anisotropic Mesoscale Eddy Transport in Ocean General Circulation Models

    NASA Astrophysics Data System (ADS)

    Reckinger, S. J.; Fox-Kemper, B.; Bachman, S.; Bryan, F.; Dennis, J.; Danabasoglu, G.

    2014-12-01

    Modern climate models are limited to coarse-resolution representations of large-scale ocean circulation that rely on parameterizations for mesoscale eddies. The effects of eddies are typically introduced by relating subgrid eddy fluxes to the resolved gradients of buoyancy or other tracers, where the proportionality is, in general, governed by an eddy transport tensor. The symmetric part of the tensor, which represents the diffusive effects of mesoscale eddies, is universally treated isotropically in general circulation models. Thus, only a single parameter, namely the eddy diffusivity, is used at each spatial and temporal location to impart the influence of mesoscale eddies on the resolved flow. However, the diffusive processes that the parameterization approximates, such as shear dispersion, potential vorticity barriers, oceanic turbulence, and instabilities, typically have strongly anisotropic characteristics. Generalizing the eddy diffusivity tensor for anisotropy extends the number of parameters to three: a major diffusivity, a minor diffusivity, and the principal axis of alignment. The Community Earth System Model (CESM) with the anisotropic eddy parameterization is used to test various choices for the newly introduced parameters, which are motivated by observations and the eddy transport tensor diagnosed from high resolution simulations. Simply setting the ratio of major to minor diffusivities to a value of five globally, while aligning the major axis along the flow direction, improves biogeochemical tracer ventilation and reduces global temperature and salinity biases. These effects can be improved even further by parameterizing the anisotropic transport mechanisms in the ocean.

  12. Development and analysis of prognostic equations for mesoscale kinetic energy and mesoscale (subgrid scale) fluxes for large-scale atmospheric models

    NASA Technical Reports Server (NTRS)

    Avissar, Roni; Chen, Fei

    1993-01-01

    Generated by landscape discontinuities (e.g., sea breezes) mesoscale circulation processes are not represented in large-scale atmospheric models (e.g., general circulation models), which have an inappropiate grid-scale resolution. With the assumption that atmospheric variables can be separated into large scale, mesoscale, and turbulent scale, a set of prognostic equations applicable in large-scale atmospheric models for momentum, temperature, moisture, and any other gaseous or aerosol material, which includes both mesoscale and turbulent fluxes is developed. Prognostic equations are also developed for these mesoscale fluxes, which indicate a closure problem and, therefore, require a parameterization. For this purpose, the mean mesoscale kinetic energy (MKE) per unit of mass is used, defined as E-tilde = 0.5 (the mean value of u'(sub i exp 2), where u'(sub i) represents the three Cartesian components of a mesoscale circulation (the angle bracket symbol is the grid-scale, horizontal averaging operator in the large-scale model, and a tilde indicates a corresponding large-scale mean value). A prognostic equation is developed for E-tilde, and an analysis of the different terms of this equation indicates that the mesoscale vertical heat flux, the mesoscale pressure correlation, and the interaction between turbulence and mesoscale perturbations are the major terms that affect the time tendency of E-tilde. A-state-of-the-art mesoscale atmospheric model is used to investigate the relationship between MKE, landscape discontinuities (as characterized by the spatial distribution of heat fluxes at the earth's surface), and mesoscale sensible and latent heat fluxes in the atmosphere. MKE is compared with turbulence kinetic energy to illustrate the importance of mesoscale processes as compared to turbulent processes. This analysis emphasizes the potential use of MKE to bridge between landscape discontinuities and mesoscale fluxes and, therefore, to parameterize mesoscale fluxes

  13. Adaptation of Mesoscale Weather Models to Local Forecasting

    NASA Technical Reports Server (NTRS)

    Manobianco, John T.; Taylor, Gregory E.; Case, Jonathan L.; Dianic, Allan V.; Wheeler, Mark W.; Zack, John W.; Nutter, Paul A.

    2003-01-01

    Methodologies have been developed for (1) configuring mesoscale numerical weather-prediction models for execution on high-performance computer workstations to make short-range weather forecasts for the vicinity of the Kennedy Space Center (KSC) and the Cape Canaveral Air Force Station (CCAFS) and (2) evaluating the performances of the models as configured. These methodologies have been implemented as part of a continuing effort to improve weather forecasting in support of operations of the U.S. space program. The models, methodologies, and results of the evaluations also have potential value for commercial users who could benefit from tailoring their operations and/or marketing strategies based on accurate predictions of local weather. More specifically, the purpose of developing the methodologies for configuring the models to run on computers at KSC and CCAFS is to provide accurate forecasts of winds, temperature, and such specific thunderstorm-related phenomena as lightning and precipitation. The purpose of developing the evaluation methodologies is to maximize the utility of the models by providing users with assessments of the capabilities and limitations of the models. The models used in this effort thus far include the Mesoscale Atmospheric Simulation System (MASS), the Regional Atmospheric Modeling System (RAMS), and the National Centers for Environmental Prediction Eta Model ( Eta for short). The configuration of the MASS and RAMS is designed to run the models at very high spatial resolution and incorporate local data to resolve fine-scale weather features. Model preprocessors were modified to incorporate surface, ship, buoy, and rawinsonde data as well as data from local wind towers, wind profilers, and conventional or Doppler radars. The overall evaluation of the MASS, Eta, and RAMS was designed to assess the utility of these mesoscale models for satisfying the weather-forecasting needs of the U.S. space program. The evaluation methodology includes

  14. Multiscale models for synoptic-mesoscale interactions in the ocean

    NASA Astrophysics Data System (ADS)

    Grooms, Ian; Shafer Smith, K.; Majda, Andrew J.

    2012-11-01

    Multiscale analysis is used to derive two sets of coupled models, each based on the same distinguished limit, to represent the interaction of the midlatitude oceanic synoptic scale-where coherent features such as jets and rings form-and the mesoscale, defined by the internal deformation scale. The synoptic scale and mesoscale overlap at low and mid latitudes, and are hence synonymous in much of the oceanographic literature; at higher latitudes the synoptic scale can be an order of magnitude larger than the deformation scale, which motivates our asymptotic approach and our nonstandard terminology. In the first model the synoptic dynamics are described by ‘Large Amplitude Geostrophic’ (LAG) equations while the eddy dynamics are quasigeostrophic. This model has order one isopycnal variation on the synoptic scale; the synoptic dynamics respond to an eddy momentum flux while the eddy dynamics respond to the baroclinically unstable synoptic density gradient. The second model assumes small isopycnal variation on the synoptic scale, but allows for a planetary scale background density gradient that may be fixed or evolved on a slower time scale. Here the large-scale equations are just the barotropic quasigeostrophic equations, and the mesoscale is modeled by the baroclinic quasigeostrophic equations. The synoptic dynamics now respond to both eddy momentum and buoyancy fluxes, but the small-scale eddy dynamics are simply advected by the synoptic-scale flow-there is no baroclinic production term in the eddy equations. The energy budget is closed by deriving an equation for the slow evolution of the eddy energy, which ensures that energy gained or lost by the synoptic-scale flow is reflected in a corresponding loss or gain by the eddies. This latter model, aided by the eddy energy equation-a key result of this paper-provides a conceptual basis through which to understand the classic baroclinic turbulence cycle.

  15. DEVELOPMENT OF A LAND-SURFACE MODEL PART I: APPLICATION IN A MESOSCALE METEOROLOGY MODEL

    EPA Science Inventory

    Parameterization of land-surface processes and consideration of surface inhomogeneities are very important to mesoscale meteorological modeling applications, especially those that provide information for air quality modeling. To provide crucial, reliable information on the diurn...

  16. Mesoscale Modelling of Westafrican Precipitation In Impetus Westafrica

    NASA Astrophysics Data System (ADS)

    Born, K.; Bachner, S.; Haase, G.; Hübener, H.; Paeth, H.; Sogalla, M.

    The objective of the IMPETUS Westafricaproject is the research on water availability, water use and management and future impacts of expected climate changes on the socio-economic development in two critical regions of Westafrica: On the northern side of the Sahara in the catchment of the Qued Drâa in Morocco, south of the Sahara and Sahel in the catchment of the river Ouémé in Benin. Precipitation is the most important input to the hydrological cycle in these regions. For any hydrologic or economic modeling we need spatially distributed precipitation fields as accurate as possible. Therefore, precipitation modeling is one scope for the meteorologists participating in IMPETUS. For detailed studies on the influence of land use changes on soil hydrology and plant growth, the spatial scale of used models should be as small as possible. Therefore, the use of mesoscale models for regional climate modelling is tested and further developped. Since causes of rainfall variability are multiscale phenomena--teleconnections with ENSO and NAO steer the rainfall variability as well as local changes like deforestation--a hierachy of models, from the global scale down to the Meso- /Micro- scale, was set up to study processes affecting rainfall variability in the regions of interest. This model chain is described in some detail, first results and fu- ture aims of research activities in the area of mesoscale modeling are shown.

  17. Utilization of satellite data in mesoscale modeling of severe weather

    NASA Technical Reports Server (NTRS)

    Warner, Thomas T.

    1987-01-01

    The Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS) data were used to model the 36 hour cyclogenesis period over the Pacific Ocean. Various combinations of VAS data, conventional radiosonde data, and gridded data from the National Weather Service global analysis were used in successive-correction and variational objective-analysis procedures. The Penn State/NCAR mesoscale model was used to test the impact of the VAS data on a 12 hour forecast of convective precipitation in the midweastern U.S.

  18. Mesoscale Modeling of the Atmosphere and Aerosols

    DTIC Science & Technology

    2000-09-30

    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 models to

  19. Mesoscale modeling of dislocations in molecular crystals

    NASA Astrophysics Data System (ADS)

    Lei, Lei; Koslowski, Marisol

    2011-02-01

    Understanding the inelastic deformation of molecular crystals is of fundamental importance to the modeling of the processing of drugs in the pharmaceutical industry as well as to the initiation of detonation in high energy density materials. In this work, we present dislocation dynamics simulations of the deformation of two molecular crystals of interest in the pharmaceutical industry, sucrose and paracetamol. The simulations calculate the yield stress of sucrose and paracetamol in good agreement with experimental observation and predict the anisotropy in the mechanical response observed in these materials. Our results show that dislocation dynamics is an effective tool to study plastic deformation in molecular crystals.

  20. Validation of an Urban Parameterization in a Mesoscale Model

    SciTech Connect

    Leach, M.J.; Chin, H.

    2001-07-19

    The Atmospheric Science Division at Lawrence Livermore National Laboratory uses the Naval Research Laboratory's Couple Ocean-Atmosphere Mesoscale Prediction System (COAMPS) for both operations and research. COAMPS is a non-hydrostatic model, designed as a multi-scale simulation system ranging from synoptic down to meso, storm and local terrain scales. As model resolution increases, the forcing due to small-scale complex terrain features including urban structures and surfaces, intensifies. An urban parameterization has been added to the Naval Research Laboratory's mesoscale model, COAMPS. The parameterization attempts to incorporate the effects of buildings and urban surfaces without explicitly resolving them, and includes modeling the mean flow to turbulence energy exchange, radiative transfer, the surface energy budget, and the addition of anthropogenic heat. The Chemical and Biological National Security Program's (CBNP) URBAN field experiment was designed to collect data to validate numerical models over a range of length and time scales. The experiment was conducted in Salt Lake City in October 2000. The scales ranged from circulation around single buildings to flow in the entire Salt Lake basin. Data from the field experiment includes tracer data as well as observations of mean and turbulence atmospheric parameters. Wind and turbulence predictions from COAMPS are used to drive a Lagrangian particle model, the Livermore Operational Dispersion Integrator (LODI). Simulations with COAMPS and LODI are used to test the sensitivity to the urban parameterization. Data from the field experiment, including the tracer data and the atmospheric parameters, are also used to validate the urban parameterization.

  1. Evaluation of an Urban Canopy Parameterization in a Mesoscale Model

    SciTech Connect

    Chin, H S; Leach, M J; Sugiyama, G A; Leone, Jr., J M; Walker, H; Nasstrom, J; Brown, M J

    2004-03-18

    A modified urban canopy parameterization (UCP) is developed and evaluated in a three-dimensional mesoscale model to assess the urban impact on surface and lower atmospheric properties. This parameterization accounts for the effects of building drag, turbulent production, radiation balance, anthropogenic heating, and building rooftop heating/cooling. USGS land-use data are also utilized to derive urban infrastructure and urban surface properties needed for driving the UCP. An intensive observational period with clear-sky, strong ambient wind and drainage flow, and the absence of land-lake breeze over the Salt Lake Valley, occurring on 25-26 October 2000, is selected for this study. A series of sensitivity experiments are performed to gain understanding of the urban impact in the mesoscale model. Results indicate that within the selected urban environment, urban surface characteristics and anthropogenic heating play little role in the formation of the modeled nocturnal urban boundary layer. The rooftop effect appears to be the main contributor to this urban boundary layer. Sensitivity experiments also show that for this weak urban heat island case, the model horizontal grid resolution is important in simulating the elevated inversion layer. The root mean square errors of the predicted wind and temperature with respect to surface station measurements exhibit substantially larger discrepancies at the urban locations than the rural counterparts. However, the close agreement of modeled tracer concentration with observations fairly justifies the modeled urban impact on the wind direction shift and wind drag effects.

  2. Development and Utilization of Regional Oceanic Modeling System (ROMS). Delicacy, Imprecision, and Uncertainty of Oceanic Simulations: An Investigation with the Regional Oceanic Modeling System (ROMS). Submesoscale Flows and Mixing in the Ocean Surface Layer Using the Regional Oceanic Modeling System (ROMS). Eddy Effects in General Circulation, Spanning Mean Currents, Mesoscale Eddies, and Topographic Generation, including Submesoscale Nests

    DTIC Science & Technology

    2012-09-30

    the broad categories of front, filaments and vortical structures. We illustrate with a few examples. South of the Gulf Stream separation point at...2011: Currents connecting communities: the decay of nearshore community similarity with ocean circulation. Ecology 92, 1193-1200. Weir , B., Y...mesoscale structures such as the warm-core Gulf Stream Rings to the north and backward streamers off of meander crests . We focus on the submesoscale

  3. Mesoscale modeling of polyelectrolyte brushes with salt.

    PubMed

    Ibergay, Cyrille; Malfreyt, Patrice; Tildesley, Dominic J

    2010-06-03

    We report dissipative particle dynamics (DPD) simulations of a polyelectrolyte brush under athermal solvent conditions. The electrostatic interactions are calculated using the particle-particle particle-mesh (PPPM) method with charges distributed over the particles. The polymer beads, counterions, co-ions, and solvent particles are modeled explicitly. The DPD simulations show a dependence of the brush height on the grafting density and the charge fraction that is typical of the nonlinear osmotic brush regime. We report the effect of the addition of salt on the structural properties of the brush. In the case of a polyelectrolyte brush with a high surface coverage, the simulations reproduce the transition between the nonlinear osmotic brush regime where the thickness of the brush is independent of the salt concentration and the salted regime where the brush height decreases weakly with the salt concentration.

  4. Three Dimensional Visualization of a Coastal Mesoscale Model

    DTIC Science & Technology

    1993-12-01

    thankful to Karen, my wife, who managed to keep the faith as well as grow a beautiful daughter, Danielle Tayler Sampson -- our first. Danielle, I ...No I I TITLE (include secutray class•ncarronii Three Dimensional Visualization of a Coastal Mesoscale Model 12 PERSONAl. AUTHOR(S) Sampson, R. Mark 1...3a TYPE OF REPORT 13b TIME COVERED 114 DATE OF REPORT (year, monA daiv; I PAGE COUN.NT Master’s Thesis Fr To 93 December 70 16 SUPPLEMENTARY NOTATION

  5. An explicit mixed numerical method for mesoscale model

    NASA Technical Reports Server (NTRS)

    Hsu, H.-M.

    1981-01-01

    A mixed numerical method has been developed for mesoscale models. The technique consists of a forward difference scheme for time tendency terms, an upstream scheme for advective terms, and a central scheme for the other terms in a physical system. It is shown that the mixed method is conditionally stable and highly accurate for approximating the system of either shallow-water equations in one dimension or primitive equations in three dimensions. Since the technique is explicit and two time level, it conserves computer and programming resources.

  6. Optogenetic stimulation of a meso-scale human cortical model

    NASA Astrophysics Data System (ADS)

    Selvaraj, Prashanth; Szeri, Andrew; Sleigh, Jamie; Kirsch, Heidi

    2015-03-01

    Neurological phenomena like sleep and seizures depend not only on the activity of individual neurons, but on the dynamics of neuron populations as well. Meso-scale models of cortical activity provide a means to study neural dynamics at the level of neuron populations. Additionally, they offer a safe and economical way to test the effects and efficacy of stimulation techniques on the dynamics of the cortex. Here, we use a physiologically relevant meso-scale model of the cortex to study the hypersynchronous activity of neuron populations during epileptic seizures. The model consists of a set of stochastic, highly non-linear partial differential equations. Next, we use optogenetic stimulation to control seizures in a hyperexcited cortex, and to induce seizures in a normally functioning cortex. The high spatial and temporal resolution this method offers makes a strong case for the use of optogenetics in treating meso scale cortical disorders such as epileptic seizures. We use bifurcation analysis to investigate the effect of optogenetic stimulation in the meso scale model, and its efficacy in suppressing the non-linear dynamics of seizures.

  7. Mesoscale modelling of crack-induced diffusivity in concrete

    NASA Astrophysics Data System (ADS)

    Nilenius, Filip; Larsson, Fredrik; Lundgren, Karin; Runesson, Kenneth

    2015-02-01

    Cracks have large impact on the diffusivity of concrete since they provide low-resistance pathways for moisture and chloride ions to migrate through the material. In this work, crack-induced diffusivity in concrete is modelled on the heterogeneous mesoscale and computationally homogenized to obtain macroscale diffusivity properties. Computations are carried out using the finite element method on three-dimensional statistical volume elements (SVEs) comprising the mesoscale constituents in terms of cement paste, aggregates and the interfacial transition zone (ITZ). The SVEs are subjected to uni-axial tension loading and cracks are simulated by use of an isotropic damage model. In a damaged finite element, the crack plane is assumed to be perpendicular to the largest principle strain, and diffusivity properties are assigned to the element only in the in-plane direction of the crack by anisotropic constitutive modelling. The numerical results show that the macroscale diffusivity of concrete can be correlated to the applied mechanical straining of the SVE and that the macroscale diffusivity increases mainly in the transversal direction relative to the axis of imposed mechanical straining.

  8. Use of observational and model-derived fields and regime model output statistics in mesoscale forecasting

    NASA Technical Reports Server (NTRS)

    Forbes, G. S.; Pielke, R. A.

    1985-01-01

    Various empirical and statistical weather-forecasting studies which utilize stratification by weather regime are described. Objective classification was used to determine weather regime in some studies. In other cases the weather pattern was determined on the basis of a parameter representing the physical and dynamical processes relevant to the anticipated mesoscale phenomena, such as low level moisture convergence and convective precipitation, or the Froude number and the occurrence of cold-air damming. For mesoscale phenomena already in existence, new forecasting techniques were developed. The use of cloud models in operational forecasting is discussed. Models to calculate the spatial scales of forcings and resultant response for mesoscale systems are presented. The use of these models to represent the climatologically most prevalent systems, and to perform case-by-case simulations is reviewed. Operational implementation of mesoscale data into weather forecasts, using both actual simulation output and method-output statistics is discussed.

  9. Anisotropic mesoscale eddy transport in ocean general circulation models

    NASA Astrophysics Data System (ADS)

    Reckinger, Scott; Fox-Kemper, Baylor; Bachman, Scott; Bryan, Frank; Dennis, John; Danabasoglu, Gokhan

    2014-11-01

    In modern climate models, the effects of oceanic mesoscale eddies are introduced by relating subgrid eddy fluxes to the resolved gradients of buoyancy or other tracers, where the proportionality is, in general, governed by an eddy transport tensor. The symmetric part of the tensor, which represents the diffusive effects of mesoscale eddies, is universally treated isotropically. However, the diffusive processes that the parameterization approximates, such as shear dispersion and potential vorticity barriers, typically have strongly anisotropic characteristics. Generalizing the eddy diffusivity tensor for anisotropy extends the number of parameters from one to three: major diffusivity, minor diffusivity, and alignment. The Community Earth System Model (CESM) with the anisotropic eddy parameterization is used to test various choices for the parameters, which are motivated by observations and the eddy transport tensor diagnosed from high resolution simulations. Simply setting the ratio of major to minor diffusivities to a value of five globally, while aligning the major axis along the flow direction, improves biogeochemical tracer ventilation and reduces temperature and salinity biases. These effects can be improved by parameterizing the oceanic anisotropic transport mechanisms.

  10. Modeling Mesoscale Eddies in the North Atlantic Ocean

    NASA Technical Reports Server (NTRS)

    Chao, Yi

    1999-01-01

    Ocean modeling plays an important role in understanding the current climatic conditions and predicting the future climate change. Modeling the ocean at eddy-permitting and/or eddy resolving resolutions (1/3 degree or higher) has a two-fold objective. One part is to represent the ocean as realistically as possible, because mesoscale eddies have an impact on the large-scale circulation. The second objective is to learn how to represent effects of mesoscale eddies without explicitly resolving them. This is particularly important for climate models which cannot be run at eddy-resolving resolutions because of the computational constraints. At JPL, a 1/6 degree latitude by 1/6 degree longitude with 37 vertical levels Atlantic Ocean model has been developed. The model is based on the Parallel Ocean Program (POP) developed at Los Alamos National Laboratory (LANL). Using the 256-processor Cray T3D, we have conducted a 40-year integration of this Atlantic eddy-resolving ocean model. A regional analysis demonstrate that many observed features associated with the Caribbean Sea eddies can be realistically simulated by this model. Analysis of this Atlantic eddy-resolving ocean model further suggests that these Caribbean Sea eddies are connected with eddies formed outside the Caribbean Sea at the confluence of the North Brazil Current (NBC) and the North Equatorial Countercurrent. The diagram of the model simulated surface current shows that the Caribbean eddies ultimately originate in the NBC retroflection region, traveling more than a year from the North Brazil coast through the Lesser Antilles into the Caribbean Sea and eventually into the Gulf of Mexico. Additional information is contained in the original.

  11. Evaluation of cloud prediction and determination of critical relative humidity for a mesoscale numerical weather prediction model

    SciTech Connect

    Seaman, N.L.; Guo, Z.; Ackerman, T.P.

    1996-04-01

    Predictions of cloud occurrence and vertical location from the Pennsylvannia State University/National Center for Atmospheric Research nonhydrostatic mesoscale model (MM5) were evaluated statistically using cloud observations obtained at Coffeyville, Kansas, as part of the Second International satellite Cloud Climatology Project Regional Experiment campaign. Seventeen cases were selected for simulation during a November-December 1991 field study. MM5 was used to produce two sets of 36-km simulations, one with and one without four-dimensional data assimilation (FDDA), and a set of 12-km simulations without FDDA, but nested within the 36-km FDDA runs.

  12. Three-dimensional parabolic equation modeling of mesoscale eddy deflection.

    PubMed

    Heaney, Kevin D; Campbell, Richard L

    2016-02-01

    The impact of mesoscale oceanography, including ocean fronts and eddies, on global scale low-frequency acoustics is examined using a fully three-dimensional parabolic equation model. The narrowband acoustic signal, for frequencies from 2 to 16 Hz, is simulated from a seismic event on the Kerguellen Plateau in the South Indian Ocean to an array of receivers south of Ascension Island in the South Atlantic, a distance of 9100 km. The path was chosen for its relevance to seismic detections from the HA10 Ascension Island station of the International Monitoring System, for its lack of bathymetric interaction, and for the dynamic oceanography encountered as the sound passes the Cape of Good Hope. The acoustic field was propagated through two years (1992 and 1993) of the eddy-permitting ocean state estimation ECCO2 (Estimating the Circulation and Climate of the Ocean, Phase II) system. The range of deflection of the back-azimuth was 1.8° with a root-mean-square of 0.34°. The refraction due to mesoscale oceanography could therefore have significant impacts upon localization of distant low-frequency sources, such as seismic or nuclear test events.

  13. Hydrodynamic modeling of Singapore's coastal waters: Nesting and model accuracy

    NASA Astrophysics Data System (ADS)

    Hasan, G. M. Jahid; van Maren, Dirk Sebastiaan; Ooi, Seng Keat

    2016-01-01

    The tidal variation in Singapore's coastal waters is influenced by large-scale, complex tidal dynamics (by interaction of the Indian Ocean and the South China Sea) as well as monsoon-driven low frequency variations, requiring a model with large spatial coverage. Close to the shores, the complex topography, influenced by headlands and small islands, requires a high resolution model to simulate tidal dynamics. This can be achieved through direct nesting or multi-scale nesting, involving multiple model grids. In this paper, we investigate the effect of grid resolution and multi-scale nesting on the tidal dynamics in Singapore's coastal waters, by comparing model results with observations using different statistical techniques. The results reveal that the intermediate-scale model is generally sufficiently accurate (equal to or better than the most refined model), but also that the most refined model is only more accurate when nested in the intermediate scale model (requiring multi-scale nesting). This latter is the result of the complex tidal dynamics around Singapore, where the dominantly diurnal tidal currents are decoupled from the semi-diurnal water level variations. Furthermore, different techniques to quantify model accuracy (harmonic analysis, basic statistics and more complex statistics) are inconsistent in determining which model is more accurate.

  14. New Approaches to the Parameterization of Gravity-Wave and Flow-Blocking Drag due to Unresolved Mesoscale Orography Guided by Mesoscale Model Predictability Research

    DTIC Science & Technology

    2012-09-30

    and Flow-Blocking Drag due to Unresolved Mesoscale Orography Guided by Mesoscale Model Predictability Research Stephen D. Eckermann Geospace ...5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Geospace Science & Technology Branch

  15. Initialization of a mesoscale model for April 10, 1979, using alternative data sources

    NASA Technical Reports Server (NTRS)

    Kalb, M. W.

    1984-01-01

    A 35 km grid limited area mesoscale model was initialized with high density SESAME radiosonde data and high density TIROS-N satellite temperature profiles for April 10, 1979. These data sources were used individually and with low level wind fields constructed from surface wind observations. The primary objective was to examine the use of satellite temperature data for initializing a mesoscale model by comparing the forecast results with similar experiments employing radiosonde data. The impact of observed low level winds on the model forecasts was also investigated with experiments varying the method of insertion. All forecasts were compared with each other and with mesoscale observations for precipitation, mass and wind structure. Several forecasts produced convective precipitation systems with characteristics satisfying criteria for a mesoscale convective complex. High density satellite temperature data and balanced winds can be used in a mesoscale model to produce forecasts which verify favorably with observations.

  16. Mesoscale Simulation Data for Initializing Fast-Time Wake Transport and Decay Models

    NASA Technical Reports Server (NTRS)

    Ahmad, Nashat N.; Proctor, Fred H.; Vanvalkenburg, Randal L.; Pruis, Mathew J.; LimonDuparcmeur, Fanny M.

    2012-01-01

    The fast-time wake transport and decay models require vertical profiles of crosswinds, potential temperature and the eddy dissipation rate as initial conditions. These inputs are normally obtained from various field sensors. In case of data-denied scenarios or operational use, these initial conditions can be provided by mesoscale model simulations. In this study, the vertical profiles of potential temperature from a mesoscale model were used as initial conditions for the fast-time wake models. The mesoscale model simulations were compared against available observations and the wake model predictions were compared with the Lidar measurements from three wake vortex field experiments.

  17. Observation Denial and Performance of a Local Mesoscale Model

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.; Bauman, William H., III

    2009-01-01

    .Forecasters at the 45th Weather Squadron (45 WS) use observations from the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) wind tower network and the CCAFS (XMR) daily rawinsonde observations (RAOB) to issue and verify wind advisories and warnings for operations. These observations are also used by the National Weather Service (NWS) Spaceflight Meteorology Group (SMG) in Houston, Texas and the NWS Melbourne, Florida (NWS MLB) to initialize their locally-run mesoscale models. In addition, SMG uses these observations to support shuttle landings at the Shuttle Landing Facility (SLF). Due to impending budget cuts, some or all of the wind towers on the east-central Florida mainland and the XMR RAOBs may be eliminated. The locations of the mainland towers and XMR RAOB site are shown in Figure 1. The loss of these data may impact the forecast capability of the 45 WS, SMG and NWS MLB.

  18. The Challenge of Forecasting the Onset and Development of Radiation Fog Using Mesoscale Atmospheric Models

    NASA Astrophysics Data System (ADS)

    Steeneveld, G. J.; Ronda, R. J.; Holtslag, A. A. M.

    2015-02-01

    The numerical weather prediction of radiation fog is challenging, as many models typically show large biases for the timing of the onset and dispersal of the fog, as well as for its depth and liquid water content. To understand the role of physical processes, i.e. turbulence, radiation, land-surface coupling, and microphysics, we evaluate the HARMONIE and Weather Research and Forecasting (WRF) mesoscale models for two contrasting warm fog episodes at the relatively flat terrain around the Cabauw tower facility in the Netherlands. One case involves a radiation fog that arose in calm anticyclonic conditions, and the second is a radiation fog that developed just after a cold front passage. The WRF model represents the radiation fog well, while the HARMONIE model forecasts a stratus lowering fog layer in the first case and hardly any fog in the second case. Permutations of parametrization schemes for boundary-layer mixing, radiation and microphysics, each for two levels of complexity, have been evaluated within the WRF model. It appears that the boundary-layer formulation is critical for forecasting the fog onset, while for fog dispersal the choice of the microphysical scheme is a key element, where a double-moment scheme outperforms any of the single-moment schemes. Finally, the WRF model results appear to be relatively insensitive to horizontal grid spacing, but nesting deteriorates the modelled fog formation. Increasing the domain size leads to a more scattered character of the simulated fog. Model results with one-way or two-way nesting show approximately comparable results.

  19. A hierarchical nest survival model integrating incomplete temporally varying covariates

    PubMed Central

    Converse, Sarah J; Royle, J Andrew; Adler, Peter H; Urbanek, Richard P; Barzen, Jeb A

    2013-01-01

    Nest success is a critical determinant of the dynamics of avian populations, and nest survival modeling has played a key role in advancing avian ecology and management. Beginning with the development of daily nest survival models, and proceeding through subsequent extensions, the capacity for modeling the effects of hypothesized factors on nest survival has expanded greatly. We extend nest survival models further by introducing an approach to deal with incompletely observed, temporally varying covariates using a hierarchical model. Hierarchical modeling offers a way to separate process and observational components of demographic models to obtain estimates of the parameters of primary interest, and to evaluate structural effects of ecological and management interest. We built a hierarchical model for daily nest survival to analyze nest data from reintroduced whooping cranes (Grus americana) in the Eastern Migratory Population. This reintroduction effort has been beset by poor reproduction, apparently due primarily to nest abandonment by breeding birds. We used the model to assess support for the hypothesis that nest abandonment is caused by harassment from biting insects. We obtained indices of blood-feeding insect populations based on the spatially interpolated counts of insects captured in carbon dioxide traps. However, insect trapping was not conducted daily, and so we had incomplete information on a temporally variable covariate of interest. We therefore supplemented our nest survival model with a parallel model for estimating the values of the missing insect covariates. We used Bayesian model selection to identify the best predictors of daily nest survival. Our results suggest that the black fly Simulium annulus may be negatively affecting nest survival of reintroduced whooping cranes, with decreasing nest survival as abundance of S. annulus increases. The modeling framework we have developed will be applied in the future to a larger data set to evaluate the

  20. A hierarchical nest survival model integrating incomplete temporally varying covariates.

    PubMed

    Converse, Sarah J; Royle, J Andrew; Adler, Peter H; Urbanek, Richard P; Barzen, Jeb A

    2013-11-01

    Nest success is a critical determinant of the dynamics of avian populations, and nest survival modeling has played a key role in advancing avian ecology and management. Beginning with the development of daily nest survival models, and proceeding through subsequent extensions, the capacity for modeling the effects of hypothesized factors on nest survival has expanded greatly. We extend nest survival models further by introducing an approach to deal with incompletely observed, temporally varying covariates using a hierarchical model. Hierarchical modeling offers a way to separate process and observational components of demographic models to obtain estimates of the parameters of primary interest, and to evaluate structural effects of ecological and management interest. We built a hierarchical model for daily nest survival to analyze nest data from reintroduced whooping cranes (Grus americana) in the Eastern Migratory Population. This reintroduction effort has been beset by poor reproduction, apparently due primarily to nest abandonment by breeding birds. We used the model to assess support for the hypothesis that nest abandonment is caused by harassment from biting insects. We obtained indices of blood-feeding insect populations based on the spatially interpolated counts of insects captured in carbon dioxide traps. However, insect trapping was not conducted daily, and so we had incomplete information on a temporally variable covariate of interest. We therefore supplemented our nest survival model with a parallel model for estimating the values of the missing insect covariates. We used Bayesian model selection to identify the best predictors of daily nest survival. Our results suggest that the black fly Simulium annulus may be negatively affecting nest survival of reintroduced whooping cranes, with decreasing nest survival as abundance of S. annulus increases. The modeling framework we have developed will be applied in the future to a larger data set to evaluate the

  1. A hierarchical nest survival model integrating incomplete temporally varying covariates

    USGS Publications Warehouse

    Converse, Sarah J.; Royle, J. Andrew; Adler, Peter H.; Urbanek, Richard P.; Barzan, Jeb A.

    2013-01-01

    Nest success is a critical determinant of the dynamics of avian populations, and nest survival modeling has played a key role in advancing avian ecology and management. Beginning with the development of daily nest survival models, and proceeding through subsequent extensions, the capacity for modeling the effects of hypothesized factors on nest survival has expanded greatly. We extend nest survival models further by introducing an approach to deal with incompletely observed, temporally varying covariates using a hierarchical model. Hierarchical modeling offers a way to separate process and observational components of demographic models to obtain estimates of the parameters of primary interest, and to evaluate structural effects of ecological and management interest. We built a hierarchical model for daily nest survival to analyze nest data from reintroduced whooping cranes (Grus americana) in the Eastern Migratory Population. This reintroduction effort has been beset by poor reproduction, apparently due primarily to nest abandonment by breeding birds. We used the model to assess support for the hypothesis that nest abandonment is caused by harassment from biting insects. We obtained indices of blood-feeding insect populations based on the spatially interpolated counts of insects captured in carbon dioxide traps. However, insect trapping was not conducted daily, and so we had incomplete information on a temporally variable covariate of interest. We therefore supplemented our nest survival model with a parallel model for estimating the values of the missing insect covariates. We used Bayesian model selection to identify the best predictors of daily nest survival. Our results suggest that the black fly Simulium annulus may be negatively affecting nest survival of reintroduced whooping cranes, with decreasing nest survival as abundance of S. annulus increases. The modeling framework we have developed will be applied in the future to a larger data set to evaluate the

  2. Air Pollution Modeling Using A 3-d Hemispheric Nested Model

    NASA Astrophysics Data System (ADS)

    Frohn, L. M.; Christensen, J. H.; Brandt, J.; Hertel, O.

    A 3-D Eulerian transport-chemistry model based on modules and parameterisations from models developed over the last decade at the National Environmental Research Institute (DREAM, DEHM, ACDEP and DEOM) has been developed. The model is hemispheric with currently two nests implemented. The horizontal resolution in the mother domain is 150 km x 150 km. First nest covers the European area wit,h a 50 km x 50 km resolution, second covers the Scandinavian area with a resolution of 16.67 km x 16.67 km. The model employs a chemical scheme (originally 53 species) which has been modified to include a detailed description of the nitrogen chemistry. The concentration of air pollutants, such as sulfur and nitrogen in various forms, has been calculated with the model, applying no nesting as well as one and two nests. The calculated values have been validated by comparison to measurements from more than 200 EMEP monitoring stations. Furthermore deposition of nitrogen to marine waters has been estimated with the model. The goal is to obtain an improved description of spatial and temporal variations in the nutrient deposition to the marine environment. In the presentation the physics and chemistry of the model will be shortly described. Validations of the model calculations by comparison to EMEP measurements will be shown and discussed together with the results of the deposition calculations.

  3. Systematic multiscale models for deep convection on mesoscales

    NASA Astrophysics Data System (ADS)

    Klein, Rupert; Majda, Andrew J.

    2006-11-01

    This paper builds on recent developments of a unified asymptotic approach to meteorological modeling [ZAMM, 80: 765 777, 2000, SIAM Proc. App. Math. 116, 227 289, 2004], which was used successfully in the development of Systematic multiscale models for the tropics in Majda and Klein [J. Atmosph. Sci. 60: 393 408, 2003] and Majda and Biello [PNAS, 101: 4736 4741, 2004]. Biello and Majda [J. Atmosph. Sci. 62: 1694 1720, 2005]. Here we account for typical bulk microphysics parameterizations of moist processes within this framework. The key steps are careful nondimensionalization of the bulk microphysics equations and the choice of appropriate distinguished limits for the various nondimensional small parameters that appear. We are then in a position to study scale interactions in the atmosphere involving moist physics. We demonstrate this by developing two systematic multiscale models that are motivated by our interest in mesoscale organized convection. The emphasis here is on multiple length scales but common time scales. The first of these models describes the short-time evolution of slender, deep convective hot towers with horizontal scale ~ 1 km interacting with the linearized momentum balance on length and time scales of (10 km/3 min). We expect this model to describe how convective inhibition may be overcome near the surface, how the onset of deep convection triggers convective-scale gravity waves, and that it will also yield new insight into how such local convective events may conspire to create larger-scale strong storms. The second model addresses the next larger range of length and time scales (10 km, 100 km, and 20 min) and exhibits mathematical features that are strongly reminiscent of mesoscale organized convection. In both cases, the asymptotic analysis reveals how the stiffness of condensation/evaporation processes induces highly nonlinear dynamics. Besides providing new theoretical insights, the derived models may also serve as a theoretical devices

  4. Operational Assimilation of GOES Data into a Mesoscale Model

    NASA Technical Reports Server (NTRS)

    Lapenta, William; Suggs, Ron; McNider, Richard; Jedlovec, Gary; Dembek, Scott

    2000-01-01

    A technique has been developed for assimilating GOES-derived skin temperature tendencies and insolation into the surface energy budget equation of a mesoscale model so that the simulated rate of temperature change closely agrees with the satellite observations. A critical assumption of the technique is that the availability of moisture (either from the soil or vegetation) is the least known term in the model's surface energy budget. Therefore, the simulated latent heat flux, which is a function of surface moisture availability, is adjusted based upon differences between the modeled and satellite- observed skin temperature tendencies. An advantage of this technique is that satellite temperature tendencies are assimilated in an energetically consistent manner that avoids energy imbalances and surface stability problems that arise from direct assimilation of surface shelter temperatures. The fact that the rate of change of the satellite skin temperature is used rather than the absolute temperature means that sensor calibration is not as critical. The technique has been employed on a semi-operational basis at the Global Hydrology and Climate Center (GHCC) within the Penn State/National Center for Atmospheric Research (PSU/NCAR) Mesoscale Model (MM5) since 1 November 1998. We performed the assimilation on a model grid centered over the Southeastern US. In addition, a control run without assimilation was performed to provide insight into the performance of the assimilation technique. Bulk verification statistics (BIAS and RMSE) of surface air temperature and relative humidity of more than 250 case days has been performed to date. Results show that assimilation of the satellite data results reduces both the bias and RMSE for simulations of surface air temperature and relative humidity. We are working with forecasters at the National Weather Service Forecast Office located in Birmingham, AL to evaluate the impact of the assimilation on precipitation forecasts. In addition

  5. Performance of a Local Mesoscale Model with Data Denial

    NASA Technical Reports Server (NTRS)

    Watson, Leela; Baumann, William H., III

    2008-01-01

    Forecasters at the 45th Weather Squadron (45 WS) use observations from the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) wind tower network and daily rawinsonde observations (RAOB) to issue and verify wind advisories, watches, and warnings for operations. They are also used by the Spaceflight Meteorology Group and Melbourne, Florida National Weather Service to initialize locally run mesoscale models. Due to impending budget cuts, some or all of the mainland wind towers and RAOBs may be eliminated, The loss of these data may significantly impact the forecast capability of the 45 WS and SMG. The Applied Meteorology Unit (AMU) was tasked to conduct an objective independent modeling study to determine how important these observations are to the accuracy of the model output used by the forecasters as input to their forecasts. To accomplish this, the AMU performed a sensitivity study using the Weather Research and Forecasting (WRF) model run with and without KSC/CCAFS wind tower and CCAFS RAOB observations and assessed the accuracy of model forecasts by comparing them to the observations.

  6. Analysis of Surface Heterogeneity Effects with Mesoscale Terrestrial Modeling Platforms

    NASA Astrophysics Data System (ADS)

    Simmer, C.

    2015-12-01

    An improved understanding of the full variability in the weather and climate system is crucial for reducing the uncertainty in weather forecasting and climate prediction, and to aid policy makers to develop adaptation and mitigation strategies. A yet unknown part of uncertainty in the predictions from the numerical models is caused by the negligence of non-resolved land surface heterogeneity and the sub-surface dynamics and their potential impact on the state of the atmosphere. At the same time, mesoscale numerical models using finer horizontal grid resolution [O(1)km] can suffer from inconsistencies and neglected scale-dependencies in ABL parameterizations and non-resolved effects of integrated surface-subsurface lateral flow at this scale. Our present knowledge suggests large-eddy-simulation (LES) as an eventual solution to overcome the inadequacy of the physical parameterizations in the atmosphere in this transition scale, yet we are constrained by the computational resources, memory management, big-data, when using LES for regional domains. For the present, there is a need for scale-aware parameterizations not only in the atmosphere but also in the land surface and subsurface model components. In this study, we use the recently developed Terrestrial Systems Modeling Platform (TerrSysMP) as a numerical tool to analyze the uncertainty in the simulation of surface exchange fluxes and boundary layer circulations at grid resolutions of the order of 1km, and explore the sensitivity of the atmospheric boundary layer evolution and convective rainfall processes on land surface heterogeneity.

  7. Random-forcing model of the mesoscale oceanic eddies

    NASA Astrophysics Data System (ADS)

    Berloff, Pavel S.

    2005-04-01

    The role of mesoscale oceanic eddies in driving large-scale currents is studied in an eddy-resolving midlatitude double-gyre ocean model. The reference solution is decomposed into large-scale and eddy components in a way which is dynamically consistent with a non-eddy-resolving ocean model. That is, the non-eddy-resolving solution driven by this eddy-forcing history, calculated on the basis of this decomposition, correctly approximates the original flow. The main effect of the eddy forcing on the large-scale flow is to enhance the eastward-jet extension of the subtropical western boundary current. This is an anti-diffusive process, which cannot be represented in terms of turbulent diffusion. It is shown that the eddy-forcing history can be approximated as a space-time correlated, random-forcing process in such a way that the non-eddy-resolving solution correctly approximates the reference solution. Thus, the random-forcing model can potentially replace the diffusion model, which is commonly used to parameterize eddy effects on the large-scale currents. The eddy-forcing statistics are treated as spatially inhomogeneous but stationary, and the dynamical roles of space-time correlations and spatial inhomogeneities are systematically explored. The integral correlation time, oscillations of the space correlations, and inhomogeneity of the variance are found to be particularly important for the flow response.

  8. A Mesoscale Model of DNA and Its Renaturation

    PubMed Central

    Sambriski, E.J.; Schwartz, D.C.; de Pablo, J.J.

    2009-01-01

    A mesoscale model of DNA is presented (3SPN.1), extending the scheme previously developed by our group. Each nucleotide is mapped onto three interaction sites. Solvent is accounted for implicitly through a medium-effective dielectric constant and electrostatic interactions are treated at the level of Debye-Hückel theory. The force field includes a weak, solvent-induced attraction, which helps mediate the renaturation of DNA. Model parameterization is accomplished through replica exchange molecular dynamics simulations of short oligonucleotide sequences over a range of composition and chain length. The model describes the melting temperature of DNA as a function of composition as well as ionic strength, and is consistent with heat capacity profiles from experiments. The dependence of persistence length on ionic strength is also captured by the force field. The proposed model is used to examine the renaturation of DNA. It is found that a typical renaturation event occurs through a nucleation step, whereby an interplay between repulsive electrostatic interactions and colloidal-like attractions allows the system to undergo a series of rearrangements before complete molecular reassociation occurs. PMID:19254530

  9. Solar Radiation Estimated Through Mesoscale Atmospheric Modeling over Northeast Brazil

    NASA Astrophysics Data System (ADS)

    de Menezes Neto, Otacilio Leandro; Costa, Alexandre Araújo; Ramalho, Fernando Pinto; de Maria, Paulo Henrique Santiago

    2009-03-01

    The use of renewable energy sources, like solar, wind and biomass is rapidly increasing in recent years, with solar radiation as a particularly abundant energy source over Northeast Brazil. A proper quantitative knowledge of the incoming solar radiation is of great importance for energy planning in Brazil, serving as basis for developing future projects of photovoltaic power plants and solar energy exploitation. This work presents a methodology for mapping the incoming solar radiation at ground level for Northeast Brazil, using a mesoscale atmospheric model (Regional Atmospheric Modeling System—RAMS), calibrated and validated using data from the network of automatic surface stations from the State Foundation for Meteorology and Water Resources from Ceará (Fundação Cearense de Meteorologia e Recursos Hídricos- FUNCEME). The results showed that the model exhibits systematic errors, overestimating surface radiation, but that, after the proper statistical corrections, using a relationship between the model-predicted cloud fraction, the ground-level observed solar radiation and the incoming solar radiation estimated at the top of the atmosphere, a correlation of 0.92 with a confidence interval of 13.5 W/m2 is found for monthly data. Using this methodology, we found an estimate for annual average incoming solar radiation over Ceará of 215 W/m2 (maximum in October: 260 W/m2).

  10. Numerical Simulations of the Wintertime Optical Turbulence in Antarctica with the Mesoscale Model Meso-Nh

    NASA Astrophysics Data System (ADS)

    Lascaux, F.; Masciadri, E.; Hagelin, S.; Stoesz, J.

    2009-09-01

    Mesoscale model such as Meso-NH have proven to be highly reliable in reproducing 3D maps of optical turbulence (OT).1-3 These last years ground-based astronomy has been looking towards Antarctica, especially its summits and the continental plateau where the OT appears to be confined in a shallow layer close to the surface. However some uncertainties remain. That's why our group is focusing on a detailed study of the atmospheric flow and turbulence in the internal Antarctic Plateau. Our intention in this study is to use the Meso-NH model to do predictions of the atmospheric flow in the internal plateau. The use of this model permits us to have access to informations inside an entire 3D volume, which is not the case with observations only. Two different configurations of the model have been used: one with a low horizontal resolution (ΔX = 100 km) and another one with higher horizontal resolution with the help of the grid-nesting interactive technique (ΔX = 1 km in the innermost domain). The impact of the configuration on the meteorological parameters has already been studied.4 We present here the results obtained with Meso-Nh of forecasted CN2 profiles, surface layer thickness (SLT) and seeing values at Dome C for the 16 winter nights, whose CN2 profiles have been measured by Ref.5.

  11. Release of potential instability by mesoscale triggering - An objective model simulation. [in precipitation numerical weather forecasting

    NASA Technical Reports Server (NTRS)

    Matthews, D. A.

    1978-01-01

    The effects of mesoscale triggering on organized nonsevere convective cloud systems in the High Plains are considered. Two experiments were conducted to determine if a one-dimensional quasi-time dependent model could (1) detect soundings which were sensitive to mesoscale triggering, and (2) discriminate between cases which had mesoscale organized convection and those with no organized convection. The MESOCU model was used to analyze the available potential instability and thermodynamic potential for cloud growth. It is noted that lifting is a key factor in the release of available potential instability on the High Plains.

  12. Dynamically consistent parameterization of mesoscale eddies. Part I: Simple model

    NASA Astrophysics Data System (ADS)

    Berloff, Pavel

    2015-03-01

    This work aims at developing a framework for dynamically consistent parameterization of mesoscale eddy effects for use in non-eddy-resolving ocean circulation models. The proposed eddy parameterization framework is successfully tested on the classical, wind-driven double-gyre model, which is solved both with explicitly resolved vigorous eddy field and in the non-eddy-resolving configuration with the eddy parameterization replacing the eddy effects. The parameterization locally approximates transient eddy flux divergence by spatially localized and temporally periodic forcing, referred to as the plunger, and focuses on the linear-dynamics flow solution induced by it. The nonlinear self-interaction of this solution, referred to as the footprint, characterizes and quantifies the induced cumulative eddy forcing exerted on the large-scale flow. We find that spatial pattern and amplitude of the footprint strongly depend on the underlying large-scale and the corresponding relationships provide the basis for the eddy parameterization and its closure on the large-scale flow properties. Dependencies of the footprints on other important parameters of the problem are also systematically analyzed. The parameterization utilizes the local large-scale flow information, constructs and scales the corresponding footprints, and then sums them up over the gyres to produce the resulting eddy forcing field, which is interactively added to the model as an extra forcing. The parameterization framework is implemented in the simplest way, but it provides a systematic strategy for improving the implementation algorithm.

  13. Mesoscale Phase Field Modeling of Glass Strengthening Under Triaxial Compression

    SciTech Connect

    Li, Yulan; Sun, Xin

    2015-09-28

    Recent hydraulic bomb and confined sleeve tests on transparent armor glass materials such as borosilicate glass and soda-lime glass showed that the glass strength was a function of confinement pressure. The measured stress-strain relation is not a straight line as most brittle materials behave under little or no confinement. Moreover, borosilicate glass exhibited a stronger compressive strength when compared to soda-lime glass, even though soda-lime has higher bulk and shear moduli as well as apparent yield strength. To better understand these experimental findings, a mesoscale phase field model is developed to simulate the nonlinear stress versus strain behaviors under confinement by considering heterogeneity formation under triaxial compression and the energy barrier of a micro shear banding event (referred to as pseudo-slip hereafter) in the amorphous glass. With calibrated modeling parameters, the simulation results demonstrate that the developed phase field model can quantitatively predict the pressure-dependent strength, and it can also explain the difference between the two types of glasses from the perspective of energy barrier associated with a pseudo-slip event.

  14. A spatial model of waterfowl nest site selection in grassland nesting cover

    NASA Astrophysics Data System (ADS)

    Pool, Duane Bruce

    Ducks Unlimited's (DU) mission statement is focused on providing for the annual lifecycle needs of migratory waterfowl. The largest impacts to the success and numbers of continental populations are determined by their activities on the breeding grounds. To model and therefore manage habitats and landscapes for ducks (Anas and Aythya spp.) it is necessary to understand several characteristics of their behavior. This research builds a model of nest site selection from nest probability based on remotely sensed data, presence data and minimum threshold theory. The methods used are applicable to other sensor platforms as well as other target species or phenomenon. Using data compression techniques, logistic regression, and spatial statistical functions (Ripley's k-function, a global k-function, and Multiple Response Permutation Procedure) we tested the observed point patterns and developed a point process model to predict nesting patterns. The application of this type of fine resolution database, validated by empirical data, will be more powerful than either classified remote sensing data or field level nest demographic data alone. In the largest of the five study sites, which was also the site with the greatest number of observations, the pattern of nests were significantly different from Poisson. The model developed to fit these data was tested using the other sites and the observed data on the other four sites were not shown to be significantly different from the model. The tests for spatial association showed some evidence negative association between Blue-winged Teal and Gadwall as well as between successful and unsuccessful nest. There is some evidence that a process of natural selection may exist and the future studies should be designed with this in mind. These data will be used as a baseline for future habitat manipulation and controlled experiments on the DU Goebel Ranch complex. The results of this and future studies will be used as the basis for DU strategic

  15. Probabilistic flood damage modelling at the meso-scale

    NASA Astrophysics Data System (ADS)

    Kreibich, Heidi; Botto, Anna; Schröter, Kai; Merz, Bruno

    2014-05-01

    Decisions on flood risk management and adaptation are usually based on risk analyses. Such analyses are associated with significant uncertainty, even more if changes in risk due to global change are expected. Although uncertainty analysis and probabilistic approaches have received increased attention during the last years, they are still not standard practice for flood risk assessments. Most damage models have in common that complex damaging processes are described by simple, deterministic approaches like stage-damage functions. Novel probabilistic, multi-variate flood damage models have been developed and validated on the micro-scale using a data-mining approach, namely bagging decision trees (Merz et al. 2013). In this presentation we show how the model BT-FLEMO (Bagging decision Tree based Flood Loss Estimation MOdel) can be applied on the meso-scale, namely on the basis of ATKIS land-use units. The model is applied in 19 municipalities which were affected during the 2002 flood by the River Mulde in Saxony, Germany. The application of BT-FLEMO provides a probability distribution of estimated damage to residential buildings per municipality. Validation is undertaken on the one hand via a comparison with eight other damage models including stage-damage functions as well as multi-variate models. On the other hand the results are compared with official damage data provided by the Saxon Relief Bank (SAB). The results show, that uncertainties of damage estimation remain high. Thus, the significant advantage of this probabilistic flood loss estimation model BT-FLEMO is that it inherently provides quantitative information about the uncertainty of the prediction. Reference: Merz, B.; Kreibich, H.; Lall, U. (2013): Multi-variate flood damage assessment: a tree-based data-mining approach. NHESS, 13(1), 53-64.

  16. Meso-scale modeling of irradiated concrete in test reactor

    SciTech Connect

    Giorla, Alain B.; Vaitová, M.; Le Pape, Yann; Štemberk, P.

    2015-10-18

    In this paper, we detail a numerical model accounting for the effects of neutron irradiation on concrete at the mesoscale. Irradiation experiments in test reactor (Elleuch et al.,1972), i.e., in accelerated conditions, are simulated. Concrete is considered as a two-phase material made of elastic inclusions (aggregate) subjected to thermal and irradiation-induced swelling and embedded in a cementitious matrix subjected to shrinkage and thermal expansion. The role of the hardened cement paste in the post-peak regime (brittle-ductile transition with decreasing loading rate), and creep effects are investigated. Radiation-induced volumetric expansion (RIVE) of the aggregate cause the development and propagation of damage around the aggregate which further develops in bridging cracks across the hardened cement paste between the individual aggregate particles. The development of damage is aggravated when shrinkage occurs simultaneously with RIVE during the irradiation experiment. The post-irradiation expansion derived from the simulation is well correlated with the experimental data and, the obtained damage levels are fully consistent with previous estimations based on a micromechanical interpretation of the experimental post-irradiation elastic properties (Le Pape et al.,2015). In conclusion, the proposed modeling opens new perspectives for the interpretation of test reactor experiments in regards to the actual operation of light water reactors.

  17. Meso-scale modeling of irradiated concrete in test reactor

    DOE PAGES

    Giorla, Alain B.; Vaitová, M.; Le Pape, Yann; ...

    2015-10-18

    In this paper, we detail a numerical model accounting for the effects of neutron irradiation on concrete at the mesoscale. Irradiation experiments in test reactor (Elleuch et al.,1972), i.e., in accelerated conditions, are simulated. Concrete is considered as a two-phase material made of elastic inclusions (aggregate) subjected to thermal and irradiation-induced swelling and embedded in a cementitious matrix subjected to shrinkage and thermal expansion. The role of the hardened cement paste in the post-peak regime (brittle-ductile transition with decreasing loading rate), and creep effects are investigated. Radiation-induced volumetric expansion (RIVE) of the aggregate cause the development and propagation of damagemore » around the aggregate which further develops in bridging cracks across the hardened cement paste between the individual aggregate particles. The development of damage is aggravated when shrinkage occurs simultaneously with RIVE during the irradiation experiment. The post-irradiation expansion derived from the simulation is well correlated with the experimental data and, the obtained damage levels are fully consistent with previous estimations based on a micromechanical interpretation of the experimental post-irradiation elastic properties (Le Pape et al.,2015). In conclusion, the proposed modeling opens new perspectives for the interpretation of test reactor experiments in regards to the actual operation of light water reactors.« less

  18. URBAN MORPHOLOGICAL ANALYSIS FOR MESOSCALE METEOROLOGICAL AND DISPERSION MODELING APPLICATIONS: CURRENT ISSUES

    EPA Science Inventory

    Representing urban terrain characteristics in mesoscale meteorological and dispersion models is critical to produce accurate predictions of wind flow and temperature fields, air quality, and contaminant transport. A key component of the urban terrain representation is the charac...

  19. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS

    SciTech Connect

    Anter El-Azab

    2013-04-08

    The research under this project focused on a theoretical and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical theory of dislocations to understand strain hardening and cell structure formation under monotonic loading. These aspects of crystal deformation are manifestations of the evolution of the underlying dislocation system under mechanical loading. The project had three research tasks: 1) Investigating the statistical characteristics of dislocation systems in deformed crystals. 2) Formulating kinetic equations of dislocations and coupling these kinetics equations and crystal mechanics. 3) Computational solution of coupled crystal mechanics and dislocation kinetics. Comparison of dislocation dynamics predictions with experimental results in the area of statistical properties of dislocations and their field was also a part of the proposed effort. In the first research task, the dislocation dynamics simulation method was used to investigate the spatial, orientation, velocity, and temporal statistics of dynamical dislocation systems, and on the use of the results from this investigation to complete the kinetic description of dislocations. The second task focused on completing the formulation of a kinetic theory of dislocations that respects the discrete nature of crystallographic slip and the physics of dislocation motion and dislocation interaction in the crystal. Part of this effort also targeted the theoretical basis for establishing the connection between discrete and continuum representation of dislocations and the analysis of discrete dislocation simulation results within the continuum framework. This part of the research enables the enrichment of the kinetic description with information representing the discrete dislocation systems behavior. The third task focused on the development of physics-inspired numerical methods of solution of the coupled

  20. Modeling of Mesoscale Variability in Biofilm Shear Behavior

    PubMed Central

    Barai, Pallab; Kumar, Aloke; Mukherjee, Partha P.

    2016-01-01

    Formation of bacterial colonies as biofilm on the surface/interface of various objects has the potential to impact not only human health and disease but also energy and environmental considerations. Biofilms can be regarded as soft materials, and comprehension of their shear response to external forces is a key element to the fundamental understanding. A mesoscale model has been presented in this article based on digitization of a biofilm microstructure. Its response under externally applied shear load is analyzed. Strain stiffening type behavior is readily observed under high strain loads due to the unfolding of chains within soft polymeric substrate. Sustained shear loading of the biofilm network results in strain localization along the diagonal direction. Rupture of the soft polymeric matrix can potentially reduce the intercellular interaction between the bacterial cells. Evolution of stiffness within the biofilm network under shear reveals two regimes: a) initial increase in stiffness due to strain stiffening of polymer matrix, and b) eventual reduction in stiffness because of tear in polymeric substrate. PMID:27806068

  1. Meso-Scale Radioactive Dispersion Modelling using GPU

    NASA Astrophysics Data System (ADS)

    Sunarko; Suud, Zaki

    2017-01-01

    Lagrangian Particle Dispersion Method (LPDM) is applied to model atmospheric dispersion of radioactive material in a meso-scale of a few tens of kilometers for site study purpose. Empirical relationships are used to determine the dispersion coefficient for various atmospheric stabilities. Diagnostic 3-D wind field is created based on data from a meteorological station using mass-conservation principle. Particles imitating radioactive pollutant are dispersed in the wind-field as a point source. Time-integrated air concentration is calculated using kernel density estimator (KDE) in the lowest layer of the atmosphere. Parallel code is developed for GTX-660Ti GPU with a total of 1344 scalar processors using CUDA programming. Significant speedup of about 20 times is achieved compared to the serial version of the code while accuracy is kept at reasonable level. Only small differences in particle positions and grid doses are observed when using the same sets of random number and meteorological data in both CPU and GPU versions of the code.

  2. A concurrent precursor inflow method for LES of atmospheric boundary layer flows with variable inflow direction for coupling with meso-scale models

    NASA Astrophysics Data System (ADS)

    Munters, Wim; Meneveau, Charles; Meyers, Johan

    2014-11-01

    In order to incorporate multiple scales of meteorological phenomena in atmospheric simulations, subsequent nesting of meso-scale models is often used. However, the spatial and temporal resolution in such models is too coarse to resolve the three-dimensional turbulent eddies that are characteristic for atmospheric boundary layer flows. This motivates the development of tools to couple meso-scale models to Large-Eddy Simulations (LES), in which turbulent fluctuations are explicitly resolved. A major challenge in this area is the spin-up region near the inlet of the LES in which the flow has to evolve from a RANS-like inflow, originating from the meso-scale model, to a fully turbulent velocity field. We propose a generalized concurrent precursor inflow method capable of imposing boundary conditions for time-varying inflow directions. The method is based on a periodic fully-developed precursor boundary-layer simulation that is dynamically rotated with the wind direction that drives the main LES. In this way realistic turbulent inflow conditions are applied while still retaining flexibility to dynamically adapt to meso-scale variations in wind directions. Applications to wind simulations with varying inflow directions, and comparisons to conventional coupling methods are shown. Work supported by ERC (ActiveWindFarms, Grant No: 306471). CM is supported by NSF (Grant No. 1243482).

  3. A survey of nested grid techniques and their potential for use within the MASS weather prediction model

    NASA Technical Reports Server (NTRS)

    Koch, Steven E.; Mcqueen, Jeffery T.

    1987-01-01

    A survey of various one- and two-way interactive nested grid techniques used in hydrostatic numerical weather prediction models is presented and the advantages and disadvantages of each method are discussed. The techniques for specifying the lateral boundary conditions for each nested grid scheme are described in detail. Averaging and interpolation techniques used when applying the coarse mesh grid (CMG) and fine mesh grid (FMG) interface conditions during two-way nesting are discussed separately. The survey shows that errors are commonly generated at the boundary between the CMG and FMG due to boundary formulation or specification discrepancies. Methods used to control this noise include application of smoothers, enhanced diffusion, or damping-type time integration schemes to model variables. The results from this survey provide the information needed to decide which one-way and two-way nested grid schemes merit future testing with the Mesoscale Atmospheric Simulation System (MASS) model. An analytically specified baroclinic wave will be used to conduct systematic tests of the chosen schemes since this will allow for objective determination of the interfacial noise in the kind of meteorological setting for which MASS is designed. Sample diagnostic plots from initial tests using the analytic wave are presented to illustrate how the model-generated noise is ascertained. These plots will be used to compare the accuracy of the various nesting schemes when incorporated into the MASS model.

  4. Analysis of a Mesoscale Model for Depicting Rain-on-Snow Flooding Events in Mountainous Terrain

    NASA Astrophysics Data System (ADS)

    Morehead, M. D.; Dawson, P.; Seyfried, M. S.

    2002-12-01

    Cold season rain-on-snow events are one of the major sources of flooding in the Pacific Northwest. Accurate modeling of the atmospheric fields forcing these events is leading to a better understanding of the atmospheric conditions behind these events and to better prediction of these floods. A mesoscale atmospheric model (RAMS) with nested grids is being used for high resolution simulations of winter precipitation and other climate variables in the Owyhee mountains of southwestern Idaho. The Reynolds Creek Experimental Watershed (RCEW) contains a dense array of meteorologic and hydrologic instrumentation with which to test the spatial and temporal hydrologic and atmospheric models. The large number of precipitation gauges in the RCEW cover a wide range of precipitation zones found in mountainous terrain. These gauges allow for a thorough assessment of the areal distribution and timing of modeled versus measured precipitation and temperature. A comparison of the modeled and measured data from two winter storms associated with rain-on-snow events shows close agreement in the spatial and temporal distributions of precipitation, temperature and other variables. The model correctly predicts the spatial distribution of precipitation and the temporal conversion from snow to rain-on-snow in the lower elevations of the watershed. The modeled precipitation is typically slightly lower than the measured values. Some of the high frequency (hourly) weather variability was not captured by the model, presumably due to lack of sufficient data in the initialization process. The longer term goal is to develop a tool for generating detailed weather information for winter time hydrologic studies including cold season flooding processes and to better understand the processes controlling winter flooding.

  5. Observation Denial and Performance of a Local Mesoscale Model

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.; Bauman, William H., III

    2009-01-01

    Forecasters at the 45th Weather Squadron (45 WS) use observations from the Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) wind tower network and the CCAFS (XMR) daily rawinsonde observations (RAOB) to issue and verify wind advisories and warnings for operations. These observations are also used by the Spaceflight Meteorology Group (SMG) in Houston, Texas and the Melbourne, Florida National Weather Service office to initialize their locally run mesoscale models. SMG also uses the observations to support shuttle landings at the KSC Shuttie Landing Facility. Due to impending budget cuts, some or all of the KSC/CCAFS wind towers on the east-central Florida mainland and the XMR RAOBs may be eliminated. The loss of these data may impact the forecast capability of the 45 WS and SMG. The Applied Meteorology Unit (AMU) was tasked to conduct a modeling study to determine how important these observations are to the accuracy of the model output used by the forecasters as input to their forecasts. To accomplish this, the AMU performed a sensitivity study using the Weather Research and Forecasting (NRF) model initialized with and without KSC/CCAFS wind tower and XMR RAOB observations. The AMU assessed the accuracy of model output by comparing peak wind forecasts with operationally significant wind advisory and warning criteria forecast by the 45 WS. To assess model performance when initialized with and without some of the wind tower and XMR RAOB observations, the AMU conducted a subjective analysis by displaying model wind forecasts graphically with the observations overlaid for comparison and they conducted an objective analysis by comparing the maximum peak wind forecast to the maximum peak wind observed within the KSC/CCAFS wind tower network. Data were collected for twelve warm season cases and eight cool season cases from June - September 2007 and November - January 2008, respectively. For each case chosen, the 45 WS must have issued a wind advisory

  6. Mesoscale modelling of water vapour in the tropical UTLS: two case studies from the HIBISCUS campaign

    NASA Astrophysics Data System (ADS)

    Marécal, V.; Durry, G.; Longo, K.; Freitas, S.; Rivière, E. D.; Pirre, M.

    2006-08-01

    In this study, we evaluate the ability of the BRAMS mesoscale model compared to ECMWF global analysis to simulate the observed vertical variations of water vapour in the tropical upper troposphere and lower stratosphere (UTLS). The observations are balloon-borne measurements of water vapour mixing ratio and temperature from micro-SDLA (Tunable Diode Laser Spectrometer) instrument. Data from two balloon flights performed during the 2004 HIBISCUS field campaign are used to compare with the mesoscale simulations and to ECMWF analysis. The mesoscale model performs significantly better than ECMWF analysis for water vapour in the upper troposphere and similarly or slightly worse for temperature. The improvement provided by the mesoscale model for water vapour comes mainly from (i) the enhanced vertical resolution in the UTLS (250 m for BRAMS and ~1 km for ECMWF model) and (ii) the more detailed microphysical parameterization providing ice supersaturations as in the observations. The ECMWF vertical resolution (~1 km) is too coarse to capture the observed fine scale vertical variations of water vapour in the UTLS. In near saturated or supersaturated layers, the mesoscale model relative humidity with respect to ice saturation is close to observations provided that the temperature profile is realistic. For temperature, ECMWF analysis gives good results partly thanks to data assimilation. The analysis of the mesoscale model results showed that in undersaturated layers, the water vapour profile depends mainly on the dynamics. In saturated/supersaturated layers, microphysical processes play an important role and have to be taken into account on top of the dynamical processes to understand the water vapour profiles. In the lower stratosphere, the ECMWF model and the BRAMS model give very similar water vapour profiles that are significantly dryer than micro-SDLA measurements. This similarity comes from the fact that BRAMS is initialised using ECMWF analysis and that no mesoscale

  7. Mesoscale modeling study of severe convection over complex terrain

    NASA Astrophysics Data System (ADS)

    Zhang, Ying; Meng, Zhiyong; Zhu, Peijun; Su, Tao; Zhai, Guoqing

    2016-11-01

    Short squall lines that occurred over Lishui, southwestern Zhejiang Province, China, on 5 July 2012, were investigated using the WRF model based on 1°×1° gridded NCEP Final Operational Global Analysis data. The results from the numerical simulations were particularly satisfactory in the simulated radar echo, which realistically reproduced the generation and development of the convective cells during the period of severe convection. The initiation of this severe convective case was mainly associated with the uplift effect of mesoscale mountains, topographic convergence, sufficient water vapor, and enhanced low-level southeasterly wind from the East China Sea. An obvious wind velocity gradient occurred between the Donggong Mountains and the southeast coastline, which easily enabled wind convergence on the windward slope of the Donggong Mountains; both strong mid-low-level southwesterly wind and low-level southeasterly wind enhanced vertical shear over the mountains to form instability; and a vertical coupling relation between the divergence on the upper-left side of the Donggong Mountains and the convergence on the lower-left side caused the convection to develop rapidly. The convergence centers of surface streams occurred over the mountain terrain and updrafts easily broke through the lifting condensation level (LCL) because of the strong wind convergence and topographic lift, which led to water vapor condensation above the LCL and the generation of the initial convective cloud. The centers of surface convergence continually created new convective cells that moved with the southwest wind and combined along the Donggong Mountains, eventually forming a short squall line that caused severe convective weather.

  8. Mesoscale Modeling During Mixed-Phase Arctic Cloud Experiment

    SciTech Connect

    Avramov, A.; Harringston, J.Y.; Verlinde, J.

    2005-03-18

    Mixed-phase arctic stratus clouds are the predominant cloud type in the Arctic (Curry et al. 2000) and through various feedback mechanisms exert a strong influence on the Arctic climate. Perhaps one of the most intriguing of their features is that they tend to have liquid tops that precipitate ice. Despite the fact that this situation is colloidally unstable, these cloud systems are quite long lived - from a few days to over a couple of weeks. It has been hypothesized that mixed-phase clouds are maintained through a balance between liquid water condensation resulting from the cloud-top radiative cooling and ice removal by precipitation (Pinto 1998; Harrington et al. 1999). In their modeling study Harrington et al. (1999) found that the maintenance of this balance depends strongly on the ambient concentration of ice forming nucleus (IFN). In a follow-up study, Jiang et al. (2002), using only 30% of IFN concentration predicted by Meyers et al. (1992) IFN parameterization were able to obtain results similar to the observations reported by Pinto (1998). The IFN concentration measurements collected during the Mixed-Phase Arctic Cloud Experiment (M-PACE), conducted in October 2004 over the North Slope of Alaska and the Beaufort Sea (Verlinde et al. 2005), also showed much lower values then those predicted (Prenne, pers. comm.) by currently accepted ice nucleation parameterizations (e.g. Meyers et al. 1992). The goal of this study is to use the extensive IFN data taken during M-PACE to examine what effects low IFN concentrations have on mesoscale cloud structure and coastal dynamics.

  9. Nested Logit Models for Multiple-Choice Item Response Data

    ERIC Educational Resources Information Center

    Suh, Youngsuk; Bolt, Daniel M.

    2010-01-01

    Nested logit item response models for multiple-choice data are presented. Relative to previous models, the new models are suggested to provide a better approximation to multiple-choice items where the application of a solution strategy precedes consideration of response options. In practice, the models also accommodate collapsibility across all…

  10. Numerical Model Studies of the Martian Mesoscale Circulations

    NASA Technical Reports Server (NTRS)

    Segal, M.; Arritt, R. W.

    1996-01-01

    Studies concerning mesoscale topographical effects on Martian flows examined low-level jets in the near equatorial latitudes and the dynamical intensification of flow by steep terrain. Continuation of work from previous years included evaluating the dissipation of cold air mass outbreaks due to enhanced sensible heat flux, further sensitivity and scaling evaluations for generalization of the characteristics of Martian mesoscale circulation caused by horizontal sensible heat-flux gradients, and evaluations of the significance that non-uniform surface would have on enhancing the polar CO2 ice sublimation during the spring. The sensitivity of maximum and minimum atmospheric temperatures to changes in wind speed, surface albedo, and deep soil temperature was investigated.

  11. Interpreting the suspended sediment dynamics in a mesoscale river basin of Central Mexico using a nested watershed approach

    NASA Astrophysics Data System (ADS)

    Duvert, C.; Némery, J.; Gratiot, N.; Prat, C.; Collet, L.; Esteves, M.

    2009-12-01

    at the outlet, with a dominance of cohesive sediments (mainly silt and clay). Sediment delivery dynamics was found to be seasonally dependent and principally driven by the river network transport capacity. With the exception of events associated with a very high discharge peak, sub-catchments delivered very little sediment to the basin’s outlet during first events of the rainy season (corresponding to May-June period). Later on (from July until the end of the season), even low headwater sediment peaks were coupled with significant sediment fluxes at the outlet. An analysis of SSC-Q hysteresis patterns was also conducted for major flood events at each site. Anti-clockwise SSC-Q hysteresis loops were recorded most frequently at the three upland sub-catchments, while at the outlet a double-peaked SSC signal was repeatedly detected, outlining the variety in sediment contributions. The findings of this nested watershed approach suggest that during the first part of the rainy season, fine sediment loads exported from active hillslopes deposit as fluid mud layers in the lowland river channels. Once the in-channel storage capacity is loaded, the river transport potential guarantees a direct transit between headwater areas and delivery zones.

  12. Intercomparison of state-of-the-art models for wind energy resources with mesoscale models:

    NASA Astrophysics Data System (ADS)

    Olsen, Bjarke Tobias; Hahmann, Andrea N.; Sempreviva, Anna Maria; Badger, Jake; Joergensen, Hans E.

    2016-04-01

    1. Introduction Mesoscale models are increasingly being used to estimate wind conditions to identify perspective areas and sites where to develop wind farm projects. Mesoscale models are functional for giving information over extensive areas with various terrain complexities where measurements are scarce and measurement campaigns costly. Several mesoscale models and families of models are being used, and each often contains thousands of setup options. Since long-term integrations are expensive and tedious to carry out, only limited comparisons exist. To remedy this problem and for evaluating the capabilities of mesoscale models to estimate site wind conditions, a tailored benchmarking study has been co-organized by the European Wind Energy Association (EWEA) and the European Energy Research Alliance Joint Programme Wind Energy (EERA JP WIND). EWEA hosted results and ensured that participants were anonymous. The blind evaluation was performed at the Wind Energy Department of the Technical University of Denmark (DTU) with the following objectives: (1) To highlight common issues on mesoscale modelling of wind conditions on sites with different characteristics, and (2) To identify gaps and strengths of models and understand the root conditions for further evaluating uncertainties. 2. Approach Three experimental sites were selected: FINO 3 (offshore, GE), Høvsore (coastal, DK), and Cabauw (land-based, NL), and three other sites without observations based on . The three mast sites were chosen because the availability of concurrent suitable time series of vertical profiles of winds speed and other surface parameters. The participants were asked to provide hourly time series of wind speed, wind direction, temperature, etc., at various vertical heights for a complete year. The methodology used to derive the time series was left to the choice of the participants, but they were asked for a brief description of their model and many other parameters (e.g., horizontal and

  13. Weather Research and Forecasting Model with Vertical Nesting Capability

    SciTech Connect

    2014-08-01

    The Weather Research and Forecasting (WRF) model with vertical nesting capability is an extension of the WRF model, which is available in the public domain, from www.wrf-model.org. The new code modifies the nesting procedure, which passes lateral boundary conditions between computational domains in the WRF model. Previously, the same vertical grid was required on all domains, while the new code allows different vertical grids to be used on concurrently run domains. This new functionality improves WRF's ability to produce high-resolution simulations of the atmosphere by allowing a wider range of scales to be efficiently resolved and more accurate lateral boundary conditions to be provided through the nesting procedure.

  14. Case study modeling of turbulent and mesoscale fluxes over the BOREAS region

    USGS Publications Warehouse

    Vidale, P.L.; Pielke, R.A.; Steyaert, L.T.; Barr, A.

    1997-01-01

    Results from aircraft and surface observations provided evidence for the existence of mesoscale circulations over the Boreal Ecosystem-Atmosphere Study (BOREAS) domain. Using an integrated approach that included the use of analytical modeling, numerical modeling, and data analysis, we have found that there are substantial contributions to the total budgets of heat over the BOREAS domain generated by mesoscale circulations. This effect is largest when the synoptic flow is relatively weak, yet it is present under less favorable conditions, as shown by the case study presented here. While further analysis is warranted to document this effect, the existence of mesoscale flow is not surprising, since it is related to the presence of landscape patches, including lakes, which are of a size on the order of the local Rossby radius and which have spatial differences in maximum sensible heat flux of about 300 W m-2. We have also analyzed the vertical temperature profile simulated in our case study as well as high-resolution soundings and we have found vertical profiles of temperature change above the boundary layer height, which we attribute in part to mesoscale contributions. Our conclusion is that in regions with organized landscapes, such as BOREAS, even with relatively strong synoptic winds, dynamical scaling criteria should be used to assess whether mesoscale effects should be parameterized or explicitly resolved in numerical models of the atmosphere.

  15. Sensitivity of a mesoscale model to initial specification of relative humidity, liquid water and vertical motion

    NASA Technical Reports Server (NTRS)

    Kalb, M. W.; Perkey, D. J.

    1985-01-01

    The influence of synoptic scale initial conditions on the accuracy of mesoscale precipitation modeling is investigated. Attention is focused on the relative importance of the water vapor, cloud water, rain water, and vertical motion, with the analysis carried out using the Limited Area Mesoscale Prediction System (LAMPS). The fully moist primitive equation model has 15 levels and a terrain-following sigma coordinate system. A K-theory approach was implemented to model the planetary boundary layer. A total of 15 sensitivity simulations were run to investigate the effects of the synoptic initial conditions of the four atmospheric variables. The absence of synoptic cloud and rain water amounts in the initialization caused a 2 hr delay in the onset of precipitation. The delay was increased if synoptic-scale vertical motion was used instead of mesoscale values. Both the delays and a choice of a smoothed moisture field resulted in underestimations of the total rainfall.

  16. Overshooting convection during TRO-pico: mesoscale modelling of two cases hydrating the lower stratosphere

    NASA Astrophysics Data System (ADS)

    Rivière, Emmanuel; Marécal, Virginie; Khaykin, Sergey; Amarouche, Nadir; Ghysels, Mélanie; Mappe-Fogaing, Irène; Behera, Abhinna; Held, Gerhard; França, Hermes

    2016-04-01

    One of the main aims of the TRO-pico project (2010-2015) was to study the variability of overshooting convection at the local scale to try to deduce a typical impact on the TTL water at the global scale. In this study, we've identified local maximum in the water vapour profiles gathered by the balloon-borne hygrometers Pico-SDLA and Flash above Bauru, Brazil (22.3 S) during the TRO-pico campaign. We tried to link them to overshooting cells in the surrounding of Bauru with a trajectory analysis. In this study we select a couple of cases of overshooting convection both sampled by the Bauru S-Band radar and by one of the balloon-borne instruments of the TRO-pico campaign in 2012 and 2013. The selected cases are the case of March 13, 2012 (hereafter M12), sounded by both hygrometers Pico-SDLA and FLASH, and the case of January 26, 2013 (hereafter J13), sounded by Pico-SDLA. For the M12 case, local water vapour enhancements at two different altitudes due to two different cells were reported, with local enhancement of about 0.65 ppmv. For the J26 case, the water enhancement was about 1 ppmv. The corresponding mesoscale simulations with the Brazilian Regional Atmospheric Modelling System (BRAMS) using 3 nested grids with horizontal resolution down to 800 m were carried out. Simulation results are compared to Bauru's radar echo tops and and water vapour in situ measurements. As for the M12 simulation, the model is doing a rather good job in reproducing several overshooting cells, both in severity and timing. Associated stratospheric water budget are computed for each cases.

  17. Eddy Effects in the General Circulation, Spanning Mean Currents, Mesoscale Eddies, and Topographic Generation, Including Submesoscale Nests

    DTIC Science & Technology

    2014-09-30

    Alexander F. Shchepetkin (PI) James C. McWilliams and Maarten J. Molemaker (Co-PIs) Department of Atmospheric and Oceanic Sciences University of...LONG-TERM GOALS Our goals are the continuing development of the Regional Oceanic Modeling System (ROMS) with emphasis on the ability to simulate... Oceanic Sciences,Los Angeles,CA,90095 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR

  18. The evolution of the mesoscale environment of severe local storms Preliminary modeling results

    NASA Technical Reports Server (NTRS)

    Anthes, R. A.; Kuo, Y.-H.; Benjamin, S. G.; Li, Y.-F.

    1982-01-01

    A mesoscale model is employed for predicting two severe weather events observed during thy 1979 SESAME field programs. Particular attention is given to the development and decay of a low-level jet, to the formation of a mesoscale convective complex (MCC) and its modification of lower- and upper-level circulation, to the formation of mesoscale regions of heavy precipitation, the intensification of surface warm and cold fronts, the formation of drylines, dynamic coupling of upper- and low-level jets, the formation of a mountain wave, and the formation and maintenance of capping inversions. A summary of the physics and parameters of a tornado outbreak and a heavy precipitation event are given for a simple bulk-PBL formulation with no heating. A ten-layer model was demonstrated to be sufficient for generating and maintaining distinct vertical gradients of temperature, moisture, and wind across low-level inversions.

  19. A nested grid, nonhydrostatic, elastic model using a terrain-following coordinate transformation - The radiative-nesting boundary conditions

    NASA Technical Reports Server (NTRS)

    Chen, Chaing

    1991-01-01

    This study presents a nested-grid nonhydrostatic and elastic model using a terrain-following coordinate transformation as well as a unique application of grid-nesting techniques to the time-splitting elastic model. A simulation of the 10-m-high Witch of Agnesi Mountain provides the control to test this new model. The results show that the model produces the same solution as that derived from a simple linear analytic model. It is demonstrated that the new nested-grid model improves model resolution without resorting to the costly method of placing a fine-resolution grid over the entire domain. Since the wave reflection from the boundaries of the fine-grid model is well controlled, the boundary of the nested fine-grid model can be located even at the wave-active region. The model can be used to simulate various weather systems in which scale interactions are important.

  20. A shallow convection parameterization for the non-hydrostatic MM5 mesoscale model

    SciTech Connect

    Seaman, N.L.; Kain, J.S.; Deng, A.

    1996-04-01

    A shallow convection parameterization suitable for the Pennsylvannia State University (PSU)/National Center for Atmospheric Research nonhydrostatic mesoscale model (MM5) is being developed at PSU. The parameterization is based on parcel perturbation theory developed in conjunction with a 1-D Mellor Yamada 1.5-order planetary boundary layer scheme and the Kain-Fritsch deep convection model.

  1. Mesoscale Backtracking by Means of Atmospheric Transport Modeling of Xenon Plumes Measured by Radionuclide Gas Stations

    NASA Astrophysics Data System (ADS)

    Armand, P. P.; Achim, P.; Taffary, T.

    2006-12-01

    The monitoring of atmospheric radioactive xenon concentration is performed for nuclear safety regulatory requirements. It is also planned to be used for the detection of hypothetical nuclear tests in the framework of the Comprehensive nuclear-Test-Ban Treaty (CTBT). In this context, the French Atomic Energy Commission designed a high sensitive and automated fieldable station, named SPALAX, to measure the activity concentrations of xenon isotopes in the atmosphere. SPALAX stations were set up in Western Europe and have been operated quite continuously for three years or more, detecting principally xenon-133 and more scarcely xenon-135, xenon-133m and xenon-131m. There are around 150 nuclear power plants in the European Union, research reactors, reprocessing plants, medical production and application facilities releasing radioactive xenon in normal or incidental operations. A numerical study was carried out aiming to explain the SPALAX measurements. The mesoscale Atmospheric Transport Modelling involves the MM5 suite (PSU- NCAR) to predict the wind fields on nested domains, and FLEXPART, a 3D Lagrangian particle dispersion code, used to simulate the backward transport of xenon plumes detected by the SPALAX. For every event of detection, at least one potential xenon source has a significant efficiency of emission. The identified likely sources are located quite close to the SPALAX stations (some tens of kilometres), or situated farther (a few hundreds of kilometres). A base line of some mBq per cubic meter in xenon-133 is generated by the nuclear power plants. Peaks of xenon-133 ranging from tens to hundreds of mBq per cubic meter originate from a radioisotope production facility. The calculated xenon source terms required to obtain the SPALAX measurements are discussed and seem consistent with realistic emissions from the xenon sources in Western Europe.

  2. The CAOS model: a physically based, flexible hydrological model for the mesoscale

    NASA Astrophysics Data System (ADS)

    Westhoff, Martijn; Zehe, Erwin

    2014-05-01

    Hydrological models are not only tools to predict discharge, but they are also hypotheses of how a catchment functions with respect to rainfall-runoff behaviour. In this work in progress, we present a new (physically based) model concept that should ultimately be suitable to run at the mesoscale. To be able to run it efficiently on the mesoscale, the model cannot be too complex. Yet, we wanted it physically based, with explicit incorporation of dissipative structures, such as macropores and lateral preferential flow paths. Besides water fluxes it should also be able to simulate solute concentrations and energy fluxes. This helps to parameterize the model while the model is also thermodynamically consistent, meaning that it is suitable to test thermodynamic optimality principles (such as maximum entropy production principle). With these constraints in mind, we developed a model where, in each subroutine, flow is modelled in only one dimension (vertical for the unsaturated zone and lateral for subsurface storm flow, groundwater flow and stream flow routines, making the model multiple 1-D), decreasing computation time significantly. The code is developed in an object oriented way, leading to more flexibility to test different model structures. For example, we will demonstrate the effect on simulated rapid subsurface flow for different mathematical descriptions (i.e. the Darcy-Weisbach equation vs. the diffusive wave and kinematic wave equation). For this study, the model will also be evaluated for hillslopes in three different geological settings within the Attert Basin in Luxembourg.

  3. Modelling the Shock Response of Polycrystals at the Mesoscale

    NASA Astrophysics Data System (ADS)

    Case, Simon; Horie, Yuki

    2006-07-01

    Simulation of the shock compression of a copper polycrystal at the mesoscale has been carried out using a Discrete Element code. Grains were aligned in three crystal orientations with respect to the shock direction; <100>, <110>, and <111>. The polycrystal had an average grain diameter of 14μm and was impacted by a single crystal of copper at 200m/s. Results show the presence of a Particle Velocity Dispersion which attains its maximum magnitude of 8m/s at the plastic wave rise, and which is quantitatively of the same order as experimentally observed values. Non-planar elastic and plastic wave fronts are present. The shock front position distribution increases with propagation distance until its standard deviation is 0.4μm at a propagation distance of 80μm.

  4. Integrating Visualizations into Modeling NEST Simulations

    PubMed Central

    Nowke, Christian; Zielasko, Daniel; Weyers, Benjamin; Peyser, Alexander; Hentschel, Bernd; Kuhlen, Torsten W.

    2015-01-01

    Modeling large-scale spiking neural networks showing realistic biological behavior in their dynamics is a complex and tedious task. Since these networks consist of millions of interconnected neurons, their simulation produces an immense amount of data. In recent years it has become possible to simulate even larger networks. However, solutions to assist researchers in understanding the simulation's complex emergent behavior by means of visualization are still lacking. While developing tools to partially fill this gap, we encountered the challenge to integrate these tools easily into the neuroscientists' daily workflow. To understand what makes this so challenging, we looked into the workflows of our collaborators and analyzed how they use the visualizations to solve their daily problems. We identified two major issues: first, the analysis process can rapidly change focus which requires to switch the visualization tool that assists in the current problem domain. Second, because of the heterogeneous data that results from simulations, researchers want to relate data to investigate these effectively. Since a monolithic application model, processing and visualizing all data modalities and reflecting all combinations of possible workflows in a holistic way, is most likely impossible to develop and to maintain, a software architecture that offers specialized visualization tools that run simultaneously and can be linked together to reflect the current workflow, is a more feasible approach. To this end, we have developed a software architecture that allows neuroscientists to integrate visualization tools more closely into the modeling tasks. In addition, it forms the basis for semantic linking of different visualizations to reflect the current workflow. In this paper, we present this architecture and substantiate the usefulness of our approach by common use cases we encountered in our collaborative work. PMID:26733860

  5. Development of a 1D canopy module to couple mesoscale meteorogical model with building energy model

    NASA Astrophysics Data System (ADS)

    Mauree, Dasaraden; Kohler, Manon; Blond, Nadège; Clappier, Alain

    2013-04-01

    The actual global warming, highlighted by the scientific community, is due to the greenhouse gases emissions resulting from our energy consumption. This energy is mainly produced in cities (about 70% of the total energy use). Around 36% of this energy are used in buildings (residential/tertiary) and this accounts for about 20% of the greenhouse gases emissions. Moreover, the world population is more and more concentrated in urban areas, 50% of the actual world population already lives in cities and this ratio is expected to reach 70% by 2050. With the obviously increasing responsibility of cities in climate change in the future, it is of great importance to go toward more sustainable cities that would reduce the energy consumption in urban areas. The energy use inside buildings is driven by two factors: (1) the level of comfort wished by the inhabitants and (2) the urban climate. On the other hand, the urban climate is influenced by the presence of buildings. Indeed, artificial surfaces of urban areas modify the energy budget of the Earth's surface and furthermore, heat is released into the atmosphere due to the energy used by buildings. Modifications at the building scale (micro-scale) can thus have an influence on the climate of the urban areas and surroundings (meso-scale), and vice and versa. During the last decades, meso-scale models have been developed to simulate the atmospheric conditions for domain of 100-1000km wide with a resolution of few kilometers. Due to their low resolution, the effects of small obstacles (such as buildings, trees, ...) near the ground are not reproduced properly and parameterizations have been developed to represent such effects in meso-scale models. On the other side, micro-scale models have a higher resolution (around 1 meter) and consequently can better simulate the impact of obstacles on the atmospheric heat flux exchanges with the earth surface. However, only a smaller domain (less than 1km) can be simulated for the same

  6. Network-based model of the growth of termite nests.

    PubMed

    Eom, Young-Ho; Perna, Andrea; Fortunato, Santo; Darrouzet, Eric; Theraulaz, Guy; Jost, Christian

    2015-12-01

    We present a model for the growth of the transportation network inside nests of the social insect subfamily Termitinae (Isoptera, termitidae). These nests consist of large chambers (nodes) connected by tunnels (edges). The model based on the empirical analysis of the real nest networks combined with pruning (edge removal, either random or weighted by betweenness centrality) and a memory effect (preferential growth from the latest added chambers) successfully predicts emergent nest properties (degree distribution, size of the largest connected component, average path lengths, backbone link ratios, and local graph redundancy). The two pruning alternatives can be associated with different genuses in the subfamily. A sensitivity analysis on the pruning and memory parameters indicates that Termitinae networks favor fast internal transportation over efficient defense strategies against ant predators. Our results provide an example of how complex network organization and efficient network properties can be generated from simple building rules based on local interactions and contribute to our understanding of the mechanisms that come into play for the formation of termite networks and of biological transportation networks in general.

  7. Network-based model of the growth of termite nests

    NASA Astrophysics Data System (ADS)

    Eom, Young-Ho; Perna, Andrea; Fortunato, Santo; Darrouzet, Eric; Theraulaz, Guy; Jost, Christian

    2015-12-01

    We present a model for the growth of the transportation network inside nests of the social insect subfamily Termitinae (Isoptera, termitidae). These nests consist of large chambers (nodes) connected by tunnels (edges). The model based on the empirical analysis of the real nest networks combined with pruning (edge removal, either random or weighted by betweenness centrality) and a memory effect (preferential growth from the latest added chambers) successfully predicts emergent nest properties (degree distribution, size of the largest connected component, average path lengths, backbone link ratios, and local graph redundancy). The two pruning alternatives can be associated with different genuses in the subfamily. A sensitivity analysis on the pruning and memory parameters indicates that Termitinae networks favor fast internal transportation over efficient defense strategies against ant predators. Our results provide an example of how complex network organization and efficient network properties can be generated from simple building rules based on local interactions and contribute to our understanding of the mechanisms that come into play for the formation of termite networks and of biological transportation networks in general.

  8. High-Resolution Specification of the Land and Ocean Surface for Improving Regional Mesoscale Model Predictions

    NASA Technical Reports Server (NTRS)

    Case, Jonathan L.; Lazarus, Steven M.; Splitt, Michael E.; Crosson, William L.; Lapenta, William M.; Jedlovec, Gary J.; Peters-Lidard, Christa D.

    2008-01-01

    The exchange of energy and moisture between the Earth's surface and the atmospheric boundary layer plays a critical role in many meteorological processes. High-resolution, accurate representations of surface properties such as sea-surface temperature (SST), soil temperature and moisture content, ground fluxes, and vegetation are necessary to better understand the Earth-atmosphere interactions and improve numerical predictions of sensible weather. The NASA Short-term Prediction Research and Transition (SPoRT) Center has been conducting separate studies to examine the impacts of high-resolution land-surface initialization data from the Goddard Space Flight Center Land Information System (LIS) on subsequent WRF forecasts, as well as the influence of initializing WRF with SST composites derived from the MODIS instrument. This current project addresses the combined impacts of using high-resolution lower boundary data over both land (LIS data) and water (MODIS SSTs) on the subsequent daily WRF forecasts over Florida during May 2004. For this experiment, the WRF model is configured to run on a nested domain with 9- km and 3-kin grid spacing, centered on the Florida peninsula and adjacent coastal waters of the Gulf of Mexico and Atlantic Ocean. A control configuration of WRF is established to take all initial condition data from the NCEP Eta model. Meanwhile, two WRF experimental runs are configured to use high-resolution initialization data from (1) LIS land-surface data only, and (2) a combination of LIS data and high-resolution MODIS SST composites. The experiment involves running 24-hour simulations of the control WRF configuration, the MS-initialized WRF, and the LIS+MODIS-initialized WRF daily for the entire month of May 2004. All atmospheric data for initial and boundary conditions for the Control, LIS, and LIS+MODIS runs come from the NCEP Eta model on a 40-km grid. Verification statistics are generated at land surface observation sites and buoys, and the impacts

  9. Mesoscale modelling of water vapour in the tropical UTLS: two case studies from the HIBISCUS campaign

    NASA Astrophysics Data System (ADS)

    Marécal, V.; Durry, G.; Longo, K.; Freitas, S.; Rivière, E. D.; Pirre, M.

    2007-03-01

    In this study, we evaluate the ability of the BRAMS (Brazilian Regional Atmospheric Modeling System) mesoscale model compared to ECMWF global analysis to simulate the observed vertical variations of water vapour in the tropical upper troposphere and lower stratosphere (UTLS). The observations are balloon-borne measurements of water vapour mixing ratio and temperature from micro-SDLA (Tunable Diode Laser Spectrometer) instrument. Data from two balloon flights performed during the 2004 HIBISCUS field campaign are used to compare with the mesoscale simulations and to the ECMWF analysis. The observations exhibit fine scale vertical structures of water vapour of a few hundred meters height. The ECMWF vertical resolution (~1 km) is too coarse to capture these vertical structures in the UTLS. With a vertical resolution similar to ECMWF, the mesoscale model performs better than ECMWF analysis for water vapour in the upper troposphere and similarly or slightly worse for temperature. The BRAMS model with 250 m vertical resolution is able to capture more of the observed fine scale vertical variations of water vapour compared to runs with a coarser vertical resolution. This is mainly related to: (i) the enhanced vertical resolution in the UTLS and (ii) to the more detailed microphysical parameterization providing ice supersaturations as in the observations. In near saturated or supersaturated layers, the mesoscale model predicted relative humidity with respect to ice saturation is close to observations provided that the temperature profile is realistic. For temperature, the ECMWF analysis gives good results partly attributed to data assimilation. The analysis of the mesoscale model results showed that the vertical variations of the water vapour profile depends on the dynamics in unsaturated layer while the microphysical processes play a major role in saturated/supersaturated layers. In the lower stratosphere, the ECMWF model and the BRAMS model give very similar water vapour

  10. Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)

    SciTech Connect

    Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

    2014-06-01

    Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

  11. The effects of elevation data representation on mesoscale atmospheric model simulations

    SciTech Connect

    Walker, H.; Leone, J.M. Jr.; Kim, Jinwon

    1996-01-01

    Mesoscale atmospheric model simulations rely on descriptions of the land surface characteristics, which must be developed from geographic databases. Certain features of the geographic data, such as its resolution and accuracy, as well as the method of processing for use in the model, can be very important in producing accurate model simulations. The work described here is part of research effort into the relationship between these aspects of geographic data and the performance of mesoscale atmospheric models and is particularly focused on elevation data and how it is prepared for use in such models. A source for digital elevation data will typically not be at the resolution required for a given model simulation and so a resampling step is required. In addition, predictive non-linear model often cannot accept forcing at high spatial frequencies due to the terrain, thus smoothing is also required. The effect of different means of resampling and smoothing elevation data on two types of model simulations is investigated. At smaller spatial scales, nocturnal drainage winds in mountain valleys in Colorado are examined for effects on the general characteristics as well as the details of the flows. At the larger end of the mesoscale, extended simulations of California weather are examined for effects on orographic lifting, low-level convergence and divergence and ultimately rain and snow distribution.

  12. Mesoscale Modeling of the Inland Nocturnal Sea Breeze

    SciTech Connect

    Kurzeja, R.J.; Buckley, R.L.

    1995-09-12

    The mesoscale sea breeze has important consequences for many densely populated coastal environments, including convection initiation, aviation safety, and air quality. The sea breeze characteristics before and after sunset are markedly different (Sha et al 1993). A gravity current will form during the early afternoon due to the relatively large density difference between the land and sea air. During the afternoon, as the lighter land air is forced upward by the cooler dense sea air, Kelvin-Helmholtz (KH) billows often form along the interface, as well as thin regions of turbulent rising air, playing a crucial role in the mixing process (Simpson 1994). After sunset, the frontal zone expands as longwave radiation cools the surface which reduces vertical mixing. With further inland penetration, the sea breeze encounters increasingly stable air near the ground, resulting in the formation of an undular bore or cutoff vortex (Sha et al. 1993). It has been demonstrated that large-scale winds have profound effects on both the strength and inland penetration of sea breezes (Arritt 1993, among others). In general, offshore flow results in a sharper frontal discontinuity and less inland penetration, while onshore flow produces weaker fronts which may penetrate further inland. Most sea breeze studies have focused on its more dramatic daytime properties near the coast whereas inland nocturnal sea breezes have received much less attention. The reason for this neglect is a lack of good observational data in the boundary layer. Sha et al. (1991) note the necessity of high resolution data to capture the finer structures of the sea breeze. A unique opportunity to examine the nocturnal sea breeze became available at the Savannah River Site (SRS, located roughly 150 km from the Atlantic Ocean in southwestern South Carolina) during the Stable Boundary Layer Experiment (STABLE), 12-17 April, 1988. (Abstract Truncated)

  13. Studying PMMA films on silica surfaces with generic microscopic and mesoscale models

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Mukherji, D.; Daoulas, K. Ch.

    2016-10-01

    Polymer films on solid substrates present significant interest for fundamental polymer physics and industrial applications. For their mesoscale study, we develop a hybrid particle-based representation where polymers are modeled as worm-like chains and non-bonded interactions are introduced through a simple density functional. The mesoscale description is parameterized to match a generic microscopic model, which nevertheless can represent real materials. Choosing poly (methyl methacrylate) adsorbed on silica as a case study, the consistency of both models in describing conformational and structural properties in polymer films is investigated. We compare selected quantifiers of chain-shape, the structure of the adsorbed layer, as well as the statistics of loops, tails, and trains. Overall, the models are found to be consistent with each other. Some deviations in conformations and structure of adsorbed layer can be attributed to the simplified description of polymer/surface interactions and local liquid packing in the mesoscale model. These results are encouraging for a future development of pseudo-dynamical schemes, parameterizing the kinetics in the hybrid model via the dynamics of the generic microscopic model.

  14. Regional Model Nesting Within GFS Daily Forecasts Over West Africa

    NASA Technical Reports Server (NTRS)

    Druyan, Leonard M.; Fulakeza, Matthew; Lonergan, Patrick; Worrell, Ruben

    2010-01-01

    The study uses the RM3, the regional climate model at the Center for Climate Systems Research of Columbia University and the NASA/Goddard Institute for Space Studies (CCSR/GISS). The paper evaluates 30 48-hour RM3 weather forecasts over West Africa during September 2006 made on a 0.5 grid nested within 1 Global Forecast System (GFS) global forecasts. September 2006 was the Special Observing Period #3 of the African Monsoon Multidisciplinary Analysis (AMMA). Archived GFS initial conditions and lateral boundary conditions for the simulations from the US National Weather Service, National Oceanographic and Atmospheric Administration were interpolated four times daily. Results for precipitation forecasts are validated against Tropical Rainfall Measurement Mission (TRMM) satellite estimates and data from the Famine Early Warning System (FEWS), which includes rain gauge measurements, and forecasts of circulation are compared to reanalysis 2. Performance statistics for the precipitation forecasts include bias, root-mean-square errors and spatial correlation coefficients. The nested regional model forecasts are compared to GFS forecasts to gauge whether nesting provides additional realistic information. They are also compared to RM3 simulations driven by reanalysis 2, representing high potential skill forecasts, to gauge the sensitivity of results to lateral boundary conditions. Nested RM3/GFS forecasts generate excessive moisture advection toward West Africa, which in turn causes prodigious amounts of model precipitation. This problem is corrected by empirical adjustments in the preparation of lateral boundary conditions and initial conditions. The resulting modified simulations improve on the GFS precipitation forecasts, achieving time-space correlations with TRMM of 0.77 on the first day and 0.63 on the second day. One realtime RM3/GFS precipitation forecast made at and posted by the African Centre of Meteorological Application for Development (ACMAD) in Niamey, Niger

  15. Model studies on the role of moist convection as a mechanism for interaction between the mesoscales

    NASA Technical Reports Server (NTRS)

    Waight, Kenneth T., III; Song, J. Aaron; Zack, John W.; Price, Pamela E.

    1991-01-01

    A three year research effort is described which had as its goal the development of techniques to improve the numerical prediction of cumulus convection on the meso-beta and meso-gamma scales. Two MESO models are used, the MASS (mesoscale) and TASS (cloud scale) models. The primary meteorological situation studied is the 28-29 Jun. 1986 Cooperative Huntsville Meteorological Experiment (COHMEX) study area on a day with relatively weak large scale forcing. The problem of determining where and when convection should be initiated is considered to be a major problem of current approaches. Assimilation of moisture data from satellite, radar, and surface data is shown to significantly improve mesoscale simulations. The TASS model is shown to reproduce some observed mesoscale features when initialized with 3-D observational data. Convection evolution studies center on comparison of the Kuo and Fritsch-Chappell cumulus parameterization schemes to each other, and to cloud model results. The Fritsch-Chappell scheme is found to be superior at about 30 km resolution, while the Kuo scheme does surprisingly well in simulating convection down to 10 km in cases where convergence features are well-resolved by the model grid. Results from MASS-TASS interaction experiments are presented and discussed. A discussion of the future of convective simulation is given, with the conclusion that significant progress is possible on several fronts in the next few years.

  16. THE APPLICATION OF AN EVOLUTIONARY ALGORITHM TO THE OPTIMIZATION OF A MESOSCALE METEOROLOGICAL MODEL

    SciTech Connect

    Werth, D.; O'Steen, L.

    2008-02-11

    We show that a simple evolutionary algorithm can optimize a set of mesoscale atmospheric model parameters with respect to agreement between the mesoscale simulation and a limited set of synthetic observations. This is illustrated using the Regional Atmospheric Modeling System (RAMS). A set of 23 RAMS parameters is optimized by minimizing a cost function based on the root mean square (rms) error between the RAMS simulation and synthetic data (observations derived from a separate RAMS simulation). We find that the optimization can be efficient with relatively modest computer resources, thus operational implementation is possible. The optimization efficiency, however, is found to depend strongly on the procedure used to perturb the 'child' parameters relative to their 'parents' within the evolutionary algorithm. In addition, the meteorological variables included in the rms error and their weighting are found to be an important factor with respect to finding the global optimum.

  17. Hot-spot contributions in shocked high explosives from mesoscale ignition models

    NASA Astrophysics Data System (ADS)

    Levesque, G.; Vitello, P.; Howard, W. M.

    2013-06-01

    High explosive performance and sensitivity is strongly related to the mesoscale defect densities. Bracketing the population of mesoscale hot spots that are active in the shocked ignition of explosives is important for the development of predictive reactive flow models. By coupling a multiphysics-capable hydrodynamics code (ale3d) with a chemical kinetics solver (cheetah), we can parametrically analyze different pore sizes undergoing collapse in high pressure shock conditions with evolving physical parameter fields. Implementing first-principles based decomposition kinetics, burning hot spots are monitored, and the regimes of pore sizes that contribute significantly to burnt mass faction and those that survive thermal conduction on the time scales of ignition are elucidated. Comparisons are drawn between the thermal explosion theory and the multiphysics models for the determination of nominal pore sizes that burn significantly during ignition for the explosive 1,3,5-triamino-2,4,6-trinitrobenzene.

  18. Representing Hurricanes with a Nested Global Forecast Model

    NASA Astrophysics Data System (ADS)

    Otte, M. J.; Walko, R. L.; Avissar, R.

    2007-12-01

    A global forecast model is essential for predicting hurricane tracks beyond a period of ~2 days since global processes that may influence the longer-term storm tracks can be represented explicitly and there are no errors from the lateral boundary conditions that can propagate into the model domain and diminish the accuracy of the track forecasts. However, global models usually do not have enough horizontal and vertical resolution to produce meaningful hurricane intensity forecasts. Most current operational global forecast models represent the atmosphere horizontally using spherical harmonic basis functions with an equivalent resolution of ~40-50 km. The NOAA Science Advisory Board Hurricane Intensity Research Working Group recommends approximately 1-km-resolution hurricane forecasts in order to represent the important physical processes in the core region of hurricanes that are important to accurately predict hurricane intensity. Even with state-of-the-art computers, it will be many years before global forecasts with 1-km horizontal resolution are practical. To predict both hurricane tracks and intensity well, a nested global model is necessary. Large-scale processes are represented on a coarser, computationally-efficient grid while features such as hurricanes are represented on a high-resolution nest. The global model used in this study is the Ocean-Land-Atmosphere Model (OLAM) being developed at Duke University. OLAM is the global successor to the Regional Atmospheric Modeling System (RAMS), which originated at Colorado State University in 1986. OLAM uses the same physics parameterizations as RAMS, but it solves the governing equations by discretizing the atmosphere on an unstructured triangular finite-volume grid. The triangular grid uses the Arakawa-C staggering and is fully mass conservative. Since the triangular mesh is unstructured, the mesh can be refined to produce much higher horizontal resolution in areas of interest such as near hurricanes. Here, we

  19. The Adriatic Sea modelling system: a nested approach

    NASA Astrophysics Data System (ADS)

    Zavatarelli, M.; Pinardi, N.

    2003-01-01

    A modelling system for the Adriatic Sea has been built within the framework of the Mediterranean Forecasting System Pilot Project. The modelling system consists of a hierarchy of three numerical models (whole Mediterranean Sea, whole Adriatic Sea, Northern Adriatic Basin) coupled among each other by simple one-way, off-line nesting techniques, to downscale the larger scale flow field to highly resolved coastal scale fields. Numerical simulations have been carried out under climatological surface forcing. Simulations were aimed to assess the effectiveness of the nesting techniques and the skill of the system to reproduce known features of the Adriatic Sea circulation phenomenology (main circulation features, dense water formation,flow at the Otranto Strait and coastal circulation characteristics over the northern Adriatic shelf), in view of the pre-operational use of the modelling system. This paper describes the modelling system setup, and discusses the simulation results for the whole Adriatic Sea and its northern basin, comparing the simulations with the observed climatological circulation characteristics. Results obtained with the northern Adriatic model are also compared with the corresponding simulations obtained with the coarser resolution Adriatic model.

  20. A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation and first results

    NASA Astrophysics Data System (ADS)

    Spiga, Aymeric; Forget, François

    2009-02-01

    The Laboratoire de Météorologie Dynamique (LMD) Mesoscale Model is a new versatile simulator of the Martian atmosphere and environment at horizontal scales ranging from hundreds of kilometers to tens of meters. The model combines the National Centers for Environmental Prediction(NCEP)-National Center for Atmospheric Research (NCAR) fully compressible nonhydrostatic Advanced Research Weather Research and Forecasting (ARW-WRF) dynamical core, adapted to Mars, with the LMD-general circulation model (GCM) comprehensive set of physical parameterizations for the Martian dust, CO2, water, and photochemistry cycles. Since LMD-GCM large-scale simulations are also used to drive the mesoscale model at the boundaries of the chosen domain of interest, a high level of downscaling consistency is reached. To define the initial state and the atmosphere at the domain boundaries, a specific ``hybrid'' vertical interpolation from the coarse-resolution GCM fields to the high-resolution mesoscale domain is used to ensure the stability and the physical relevancy of the simulations. Used in synoptic-scale mode with a cyclic domain wrapped around the planet, the mesoscale model correctly replicates the main large-scale thermal structure and the zonally propagating waves. The model diagnostics of the near-surface pressure, wind, and temperature daily cycles in Chryse Planitia are in accordance with the Viking and Pathfinder measurements. Afternoon gustiness at the respective landing sites is adequately accounted for on the condition that convective adjustment is turned off in the mesoscale simulations. On the rims of Valles Marineris, intense daytime anabatic (~30 m s-1) and nighttime katabatic (~40 m s-1) winds are predicted. Within the canyon corridors, topographical channeling can amplify the wind a few kilometers above the ground, especially during the night. Through large-eddy simulations in Gusev Crater, the model describes the mixing layer growth during the afternoon, and the

  1. Turbulence Parameterizations for Convective Boundary Layers in High-Resolution Mesoscale Models

    DTIC Science & Technology

    2003-12-01

    radars are especially dependent on clear weather conditions for effective operations. For example, dust storms and low cloud cover were weather events...PAGES 160 14. SUBJECT TERMS Grid Resolution, Parameterizations, Boundary Layer, Mesoscale Modeling, COAMPS . 16. PRICE CODE 17. SECURITY...Parameterizations in COAMPS using aircraft measurements. This work was also supported in part by a grant of computer time from the DOD high

  2. Exploring the mesoscale activity in the Solomon Sea: A complementary approach with a numerical model and altimetric data

    NASA Astrophysics Data System (ADS)

    Gourdeau, L.; Verron, J.; Melet, A.; Kessler, W.; Marin, F.; Djath, B.

    2014-04-01

    The Solomon Sea is an area of high level of eddy kinetic energy (EKE), and represents a transit area for the low-latitude western boundary currents (LLWBCs) connecting the subtropics to the equatorial Pacific and playing a major role in ENSO dynamics. This study aims at documenting the surface mesoscale activity in the Solomon Sea for the first time. Our analysis is based on the joint analysis of altimetric data and outputs from a 1/12° model simulation. The highest surface EKE is observed in the northern part of the basin and extends southward to the central basin. An eddy tracking algorithm is used to document the characteristics and trajectories of coherent mesoscale vortices. Cyclonic eddies, generated in the south basin, are advected to the north by the LLWBCs before merging with stationary mesoscale structures present in the mean circulation. Anticyclonic eddies are less numerous. They are generated in the southeastern basin, propagate westward, reach the LLWBCs, and dissipate. The seasonal and interannual modulations of the mesoscale activity are well marked. At seasonal time scale, maximum (minimum) activity is in May-June (September). At interannual time scale, the mesoscale activity is particularly enhanced during La Niña conditions. If instabilities of the regional circulations seem to explain the generation of mesoscale features, the modulation of the mesoscale activity seems to be rather related with the intrusion at Solomon Strait of the surface South Equatorial Current, rather than to the LLWBCs, by modulating the horizontal and vertical shears suitable for instabilities.

  3. Simulating wind energy resources with mesoscale models: Intercomparison of state-of-the-art models over Northern Europe

    NASA Astrophysics Data System (ADS)

    Hahmann, A. N.

    2015-12-01

    Mesoscale models are increasingly being used to estimate wind conditions to identify perspective areas and sites where to develop wind farm projects. Mesoscale models are useful because they give information over extensive areas with various terrain complexities where measurements are scarce and measurement campaigns costly. Various mesoscale models and families of mesoscale models are being used, with thousands of setup options. Since long-term integrations are expensive and tedious to carry out, only limited comparisons exist. We have carried out a blind benchmarking study to evaluate the capabilities of mesoscale models used in wind energy to estimate site wind conditions: to highlight common issues on mesoscale modeling of wind conditions on sites with different characteristics, and to identify gaps and strengths of models and understand the root conditions for further evaluating uncertainties. Three experimental sites with tall mast measurements were selected: FINO3 (offshore), Høvsøre (coastal), and Cabauw (land-based). The participants were asked to provide hourly time series of wind speed and direction, temperature, etc., at various heights for 2011. The methods used were left to the choice of the participants, but they were asked for a detailed description of their model and many other parameters (e.g., horizontal and vertical resolution, model parameterizations, surface roughness length) that could be used to group the models and interpret the results of the intercomparison. The analysis of the time series includes comparison to observations, summarized with well-known measures such as biases, RMSE, correlations, and of sector-wise statistics, and the temporal spectra. The statistics were grouped by the models, their spatial resolution, forcing data, various integration methods, etc. The results show high fidelity of the various entries in simulating the wind climate at the offshore and coastal site. Over land and the statistics of other derived fields

  4. Mesoscale modeling of combined aerosol and photo-oxidant processes in the Eastern Mediterranean

    NASA Astrophysics Data System (ADS)

    Lazaridis, M.; Spyridaki, A.; Solberg, S.; Smolík, J.; Zdímal, V.; Eleftheriadis, K.; Aleksanropoulou, V.; Hov, O.; Georgopoulos, P. G.

    2005-03-01

    Particulate matter and photo-oxidant processes in the Eastern Mediterranean have been studied using the UAM-AERO mesoscale air quality model in conjunction with the NILU-CTM regional model. Meteorological data were obtained from the RAMS prognostic meteorological model. The modeling domain includes the eastern Mediterranean area between the Greek mainland and the island of Crete. The modeling system is applied to study the atmospheric processes in three periods, i.e. 13-16 July 2000, 26-30 July 2000 and 7-14 January 2001. The spatial and temporal distributions of both gaseous and particulate matter pollutants have been extensively studied together with the identification of major emission sources in the area. The modeling results were compared with field data obtained in the same period. The objective of the current modeling work was mainly to apply the UAM-AERO mesoscale model in the eastern Mediterranean in order to assess the performed field campaigns and determine that the applied mesoscale model is fit for this purpose. Comparison of the modeling results with measured data was performed for a number of gaseous and aerosol species. The UAM-AERO model underestimates the PM10 measured concentrations during summer and winter campaigns. Discrepancies between modeled and measured data are attributed to unresolved particulate matter emissions. Particulate matter in the area is mainly composed by sulphate, sea salt and crustal materials, and with significant amounts of nitrate, ammonium and organics. During winter the particulate matter and oxidant concentrations were lower than the summer values.

  5. The Impact of Ignoring the Level of Nesting Structure in Nonparametric Multilevel Latent Class Models

    ERIC Educational Resources Information Center

    Park, Jungkyu; Yu, Hsiu-Ting

    2016-01-01

    The multilevel latent class model (MLCM) is a multilevel extension of a latent class model (LCM) that is used to analyze nested structure data structure. The nonparametric version of an MLCM assumes a discrete latent variable at a higher-level nesting structure to account for the dependency among observations nested within a higher-level unit. In…

  6. Modeling the wind-fields of accidental releases by mesoscale forecasting

    SciTech Connect

    Albritton, J.R.; Lee, R.L.; Mobley, R.L.; Pace, J.C.; Hodur, R.A.; Lion, C.S.

    1997-07-01

    Modeling atmospheric releases even during fair weather can present a sever challenge to diagnostic, observed-data-driven, models. Such schemes are often handicapped by sparse input data from meteorological surface stations and soundings. Forecasting by persistence is only acceptable for a few hours and cannot predict important changes in the diurnal cycle or from synoptic evolution. Many accident scenarios are data-sparse in space and/or time. Here we describe the potential value of limited-area, mesoscale, forecast models for real-time emergency response. Simulated wind-fields will be passed to ARAC`s operational models to produce improved forecasts of dispersion following accidents.

  7. Mesoscale energy deposition footprint model for kiloelectronvolt cluster bombardment of solids.

    PubMed

    Russo, Michael F; Garrison, Barbara J

    2006-10-15

    Molecular dynamics simulations have been performed to model 5-keV C60 and Au3 projectile bombardment of an amorphous water substrate. The goal is to obtain detailed insights into the dynamics of motion in order to develop a straightforward and less computationally demanding model of the process of ejection. The molecular dynamics results provide the basis for the mesoscale energy deposition footprint model. This model provides a method for predicting relative yields based on information from less than 1 ps of simulation time.

  8. Toward an extended-geostrophic Euler-Poincare model for mesoscale oceanographic flow

    SciTech Connect

    Allen, J.S.; Newberger, P.A.; Holm, D.D.

    1998-07-01

    The authors consider the motion of a rotating, continuously stratified fluid governed by the hydrostatic primitive equations (PE). An approximate Hamiltonian (L1) model for small Rossby number {var_epsilon} is derived for application to mesoscale oceanographic flow problems. Numerical experiments involving a baroclinically unstable oceanic jet are utilized to assess the accuracy of the L1 model compared to the PE and to other approximate models, such as the quasigeostrophic (QG) and the geostrophic momentum (GM) equations. The results of the numerical experiments for moderate Rossby number flow show that the L1 model gives accurate solutions with errors substantially smaller than QG or GM.

  9. Mesoscale simulations of two model systems in biophysics: from red blood cells to DNAs

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Chen, Yeng-Long; Lu, Huijie; Pan, Zehao; Chang, Hsueh-Chia

    2015-12-01

    Computational modeling has become increasingly important in biophysics, but the great challenge in numerical simulations due to the multiscale feature of biological systems limits the capability of modeling in making discoveries in biology. Innovative multiscale modeling approaches are desired to bridge different scales from nucleic acids and proteins to cells and tissues. Although all-atom molecular dynamics has been successfully applied in many microscale biological processes such as protein folding, it is still prohibitively expensive for studying macroscale problems such as biophysics of cells and tissues. On the other hand, continuum-based modeling has become a mature procedure for analysis and design in many engineering fields, but new insights for biological systems in the microscale are limited when molecular details are missing in continuum-based modeling. In this context, mesoscale modeling approaches such as Langevin dynamics, lattice Boltzmann method, and dissipative particle dynamics have become popular by simultaneously incorporating molecular interactions and long-range hydrodynamic interactions, providing insights to properties on longer time and length scales than molecular dynamics. In this review, we summarized several mesoscale simulation approaches for studying two model systems in biophysics: red blood cells (RBCs) and deoxyribonucleic acids (DNAs). The RBC is a model system for cell mechanics and biological membranes, while the DNA represents a model system for biopolymers. We introduced the motivations of studying these problems and presented the key features of different mesoscale methods. Furthermore, we described the latest progresses in these methods and highlighted the major findings for modeling RBCs and DNAs. Finally, we also discussed the challenges and potential issues of different approaches.

  10. Gasdynamic modeling and parametric study of mesoscale internal combustion swing engine/generator systems

    NASA Astrophysics Data System (ADS)

    Gu, Yongxian

    The demand of portable power generation systems for both domestic and military applications has driven the advances of mesoscale internal combustion engine systems. This dissertation was devoted to the gasdynamic modeling and parametric study of the mesoscale internal combustion swing engine/generator systems. First, the system-level thermodynamic modeling for the swing engine/generator systems has been developed. The system performance as well as the potentials of both two- and four-stroke swing engine systems has been investigated based on this model. Then through parameterc studies, the parameters that have significant impacts on the system performance have been identified, among which, the burn time and spark advance time are the critical factors related to combustion process. It is found that the shorter burn time leads to higher system efficiency and power output and the optimal spark advance time is about half of the burn time. Secondly, the turbulent combustion modeling based on levelset method (G-equation) has been implemented into the commercial software FLUENT. Thereafter, the turbulent flame propagation in a generic mesoscale combustion chamber and realistic swing engine chambers has been studied. It is found that, in mesoscale combustion engines, the burn time is dominated by the mean turbulent kinetic energy in the chamber. It is also shown that in a generic mesoscale combustion chamber, the burn time depends on the longest distance between the initial ignition kernel to its walls and by changing the ignition and injection locations, the burn time can be reduced by a factor of two. Furthermore, the studies of turbulent flame propagation in real swing engine chambers show that the combustion can be enhanced through in-chamber turbulence augmentation and with higher engine frequency, the burn time is shorter, which indicates that the in-chamber turbulence can be induced by the motion of moving components as well as the intake gas jet flow. The burn time

  11. Toward a Mesoscale Model for the Dynamics of Polymer Solutions

    SciTech Connect

    Miller, G H; Trebotich, D

    2006-10-02

    To model entire microfluidic systems containing solvated polymers we argue that it is necessary to have a numerical stability constraint governed only by the advective CFL condition. Advancements in the treatment of Kramers bead-rod polymer models are presented to enable tightly-coupled fluid-particle algorithms in the context of system-level modeling.

  12. Mesoscale modeling of lake effect snow over Lake Erie - sensitivity to convection, microphysics and the water temperature

    NASA Astrophysics Data System (ADS)

    Theeuwes, N. E.; Steeneveld, G. J.; Krikken, F.; Holtslag, A. A. M.

    2010-03-01

    Lake effect snow is a shallow convection phenomenon during cold air advection over a relatively warm lake. A severe case of lake effect snow over Lake Erie on 24 December 2001 was studied with the MM5 and WRF mesoscale models. This particular case provided over 200 cm of snow in Buffalo (NY), caused three casualties and 10 million of material damage. Hence, the need for a reliable forecast of the lake effect snow phenomenon is evident. MM5 and WRF simulate lake effect snow successfully, although the intensity of the snowbelt is underestimated. It appears that significant differences occur between using a simple and a complex microphysics scheme. In MM5, the use of the simple-ice microphysics scheme results in the triggering of the convection much earlier in time than with the more sophisticated Reisner-Graupel-scheme. Furthermore, we find a large difference in the maximum precipitation between the different nested domains: Reisner-Graupel produces larger differences in precipitation between the domains than "simple ice". In WRF, the sophisticated Thompson microphysics scheme simulates less precipitation than the simple WSM3 scheme. Increased temperature of Lake Erie results in an exponential growth in the 24-h precipitation. Regarding the convection scheme, the updated Kain-Fritsch scheme (especially designed for shallow convection during lake effect snow), gives only slight differences in precipitation between the updated and the original scheme.

  13. Local Bathymetry Estimation Using Variational Inverse Modeling: A Nested Approach

    NASA Astrophysics Data System (ADS)

    Almeida, T. G.; Walker, D. T.; Farquharson, G.

    2014-12-01

    Estimation of subreach river bathymetry from remotely-sensed surface velocity data is presented using variational inverse modeling applied to the 2D depth-averaged, shallow-water equations (SWEs). A nested approach is adopted to focus on obtaining an accurate estimate of bathymetry over a small region of interest within a larger complex hydrodynamic system. This approach reduces computational cost significantly. We begin by constructing a minimization problem with a cost function defined by the error between observed and estimated surface velocities, and then apply the SWEs as a constraint on the velocity field. An adjoint SWE model is developed through the use of Lagrange multipliers, converting the unconstrained minimization problem into a constrained one. The adjoint model solution is used to calculate the gradient of the cost function with respect to bathymetry. The gradient is used in a descent algorithm to determine the bathymetry that yields a surface velocity field that is a best-fit to the observational data. In this application of the algorithm, the 2D depth-averaged flow is computed within a nested framework using Delft3D-FLOW as the forward computational model. First, an outer simulation is generated using discharge rate and other measurements from USGS and NOAA, assuming a uniform bottom-friction coefficient. Then a nested, higher resolution inner model is constructed using open boundary condition data interpolated from the outer model (see figure). Riemann boundary conditions with specified tangential velocities are utilized to ensure a near seamless transition between outer and inner model results. The initial guess bathymetry matches the outer model bathymetry, and the iterative assimilation procedure is used to adjust the bathymetry only for the inner model. The observation data was collected during the ONR Rivet II field exercise for the mouth of the Columbia River near Hammond, OR. A dual beam squinted along-track-interferometric, synthetic

  14. Parameterization of Cumulus Convective Cloud Systems in Mesoscale Forecast Models

    DTIC Science & Technology

    2012-09-30

    and the 6th moments. The development and testing of the parameterization was made using the CIMMS LES explicit warm rain microphysical model. The...implemented into the 3D dynamical framework of the CIMMS LES model where the errors of the parameterization were assessed in a realistic setting. The

  15. Nested Sphere Model for SQUID-based Impedance Magnetocardiography

    NASA Astrophysics Data System (ADS)

    Vajrala, Vijayanand; Nawarathna, Dharmakeerthi; Claycomb, James; Miller, John

    2004-03-01

    An axisymmetric FEM model is used to predict the SQUID response to changes in tissue conductivity and blood volume during the cardiac cycle. The heart is modeled as a nested sphere inside a cylindrical conducting thorax. The current density and resulting magnetic field is calculated during end systolic, end diastolic and diastolic phases. Modeling results are compared to Impedance Magnetocardiography (IMCG) measurements made using a High-Tc SQUID magnetometer in an unshielded environment .In this measurements, a low amplitude ac current is passed through the body through outer electrodes. Variations in blood flow during the cardiac cycle perturb currents that give rise to time varying magnetic fields amplitudes. Applications to inductive IMCG will be discussed.

  16. Numerical simulations of Hurricane Bertha using a mesoscale atmospheric model

    SciTech Connect

    Buckley, R.L.

    1996-08-01

    The Regional Atmospheric Model System (RAMS) has been used to simulate Hurricane Bertha as it moved toward and onto shore during the period July 10--12, 1996. Using large-scale atmospheric data from 00 UTC, 11 July (Wednesday evening) to initialize the model, a 36-hour simulation was created for a domain centered over the Atlantic Ocean east of the Florida coast near Jacksonville. The simulated onshore impact time of the hurricane was much earlier than observed (due to the use of results from the large-scale model, which predicted early arrival). However, the movement of the hurricane center (eye) as it approached the North Carolina/South Carolina coast as simulated in RAMS was quite good. Observations revealed a northerly storm track off the South Carolina coast as it moved toward land. As it approached landfall, Hurricane Bertha turned to the north-northeast, roughly paralleling the North Carolina coast before moving inland near Wilmington. Large-scale model forecasts were unable to detect this change in advance and predicted landfall near Myrtle Beach, South Carolina; RAMS, however, correctly predicted the parallel coastal movement. For future hurricane activity in the southeast, RAMS is being configured to run in an operational model using input from the large-scale pressure data in hopes of providing more information on predicted hurricane movement and landfall location.

  17. Perspective on Continuum Modeling of Mesoscale/ Macroscale Phenomena

    NASA Astrophysics Data System (ADS)

    Bammann, D. J.

    The attempt to model or predict the inelastic response or permanent deformation and failure observed in metals dates back over 180 years. Various descriptions of the post elastic response of metals have been proposed from the fields of physics, materials science (metallurgy), engineering, mechanics, and applied mathematics. The communication between these fields has improved and many of the modeling efforts today involve concepts from most or all of these fields. Early engineering description of post yield response treated the material as perfectly plastic — the material continues to deform with zero additional increase in load. These models became the basis of the mathematical theory of plasticity and were extended to account for hardening, unloading, and directional hardening. In contradistinction, rheological models treated the finite deformation of a solid similar to the deformation of a viscous fluid. In many cases of large deformation, rheological models have provided both adequate and accurate information about the deformed shape of a metal during many manufacturing processes. The treatment of geometric defects in solid bodies initiated within the mathematical theory of elasticity, the dislocation, introduced as an incompatible "cut" in a continuum body. This resulted in a very large body of literature devoted to the linear elastic study of dislocations, dislocation structures, and their interactions, and has provided essential information in the understanding of the "state" of a deformed material.

  18. Intercomparison of mesoscale meteorological models for precipitation forecasting

    NASA Astrophysics Data System (ADS)

    Richard, E.; Cosma, S.; Benoit, R.; Binder, P.; Buzzi, A.; Kaufmann, P.

    In the framework of the RAPHAEL EU project, a series of past heavy precipitation events has been simulated with different meteorological models. Rainfall hindcasts and forecasts have been produced by four models in use at various meteorological services or research centres of Italy, Canada, France and Switzerland. The paper is focused on the comparison of the computed precipitation fields with the available surface observations. The comparison is carried out for three meteorological situations which lead to severe flashflood over the Toce-Ticino catchment in Italy (6599 km2) or the Ammer catchment (709 km2) in Germany. The results show that all four models reproduced the occurrence of these heavy precipitation events. The accuracy of the computed precipitation appears to be more case-dependent than model-dependent. The sensitivity of the computed rainfall to the boundary conditions (hindcast v. forecast) was found to be rather weak, indicating that a flood forecasting system based upon a numerical meteo-hydrological simulation could be feasible in an operational context.

  19. Mesoscale modeling of smoke radiative feedback over the Sahel region

    NASA Astrophysics Data System (ADS)

    Yang, Z.; Wang, J.; Ichoku, C. M.; Ellison, L.; Zhang, F.; Yue, Y.

    2013-12-01

    This study employs satellite observations and a fully-coupled meteorology-chemistry-aerosol model, Weather Research and Forecasting model with Chemistry (WRF-Chem) to study the smoke radative feedback on surface energy budget, boundary layer processes, and atmospheric lapse rate in February 2008 over the Sahel region. The smoke emission inventories we use come from various sources, including but not limited to the Fire Locating and Modeling of Burning Emissions (FLAMBE) developed by NRL and the Fire Energetic and Emissions Research (FEER) developed by NASA GSFC. Model performance is evaluated using numerous satellite and ground-based datasets: MODIS true color images, ground-based Aerosol Optical Depth (AOD) measurements from AERONET, MODIS AOD retrievals, and Cloud-Aerosol Lidar data with Orthogonal Polarization (CALIOP) atmospheric backscattering and extinction products. Specification of smoke injection height of 650 m in WRF-Chem yields aerosol vertical profiles that are most consistent with CALIOP observations of aerosol layer height. Statistically, 5% of the CALIPSO valid measurements of aerosols in February 2008 show aerosol layers either above the clouds or between the clouds, reinforcing the importance of the aerosol vertical distribution for quantifying aerosol impact on climate in the Sahel region. The results further show that the smoke radiative feedbacks are sensitive to assumptions of black carbon and organic carbon ratio in the particle emission inventory. Also investigated is the smoke semi-direct effect as a function of cloud fraction.

  20. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics

    SciTech Connect

    Persson, Rasmus A. X.; Chu, Jhih-Wei; Voulgarakis, Nikolaos K.

    2014-11-07

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ϕ in coupling to the other equations of FHD. The resulting ϕ-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ϕ-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ϕ-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ϕ-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

  1. Mesoscale modelling of shock initiation in HMX-based explosives

    SciTech Connect

    Swift, D. C.; Mulford, R. N. R.; Winter, R. E.; Taylor, P.; Salisbury, D. A.; Harris, E. J.

    2002-01-01

    Motivation: predictive capability Want to predict initiation, detonics and performance given: {sm_bullet} Variations in composition {sm_bullet} Variations in morphology {sm_bullet}Different loading conditions Previous work on PBX and ANFO: need physically-based model rather than just mechanical calibrations

  2. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics.

    PubMed

    Persson, Rasmus A X; Voulgarakis, Nikolaos K; Chu, Jhih-Wei

    2014-11-07

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ϕ in coupling to the other equations of FHD. The resulting ϕ-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ϕ-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ϕ-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ϕ-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

  3. Range-Specific High-resolution Mesoscale Model Setup

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.

    2013-01-01

    This report summarizes the findings from an AMU task to determine the best model configuration for operational use at the ER and WFF to best predict winds, precipitation, and temperature. The AMU ran test cases in the warm and cool seasons at the ER and for the spring and fall seasons at WFF. For both the ER and WFF, the ARW core outperformed the NMM core. Results for the ER indicate that the Lin microphysical scheme and the YSU PBL scheme is the optimal model configuration for the ER. It consistently produced the best surface and upper air forecasts, while performing fairly well for the precipitation forecasts. Both the Ferrier and Lin microphysical schemes in combination with the YSU PBL scheme performed well for WFF in the spring and fall seasons. The AMU has been tasked with a follow-on modeling effort to recommended local DA and numerical forecast model design optimized for both the ER and WFF to support space launch activities. The AMU will determine the best software and type of assimilation to use, as well as determine the best grid resolution for the initialization based on spatial and temporal availability of data and the wall clock run-time of the initialization. The AMU will transition from the WRF EMS to NU-WRF, a NASA-specific version of the WRF that takes advantage of unique NASA software and datasets. 37

  4. Next-Generation Global and Mesoscale Atmospheric Models

    DTIC Science & Technology

    2013-09-30

    explore: 1. Unified high-order continuous Galerkin (CG) and discontinuous Galerkin (DG) spatial discretization methods; 2. Unified high-order... Galerkin (EBG) methods such as the spectral element (SE/CG) and discontinuous Galerkin (DG) methods. However, we have only partly showed the benefits...results of, to our knowledge, the first simulation with moisture for a discontinuous Galerkin (DG) model. The significance of this simulation is that it

  5. A sensitivity study of storm cyclones with a mesoscale model

    NASA Astrophysics Data System (ADS)

    Radtke, K. S.; Tetzlaff, G.

    2003-04-01

    Extra tropical storms caused noticeable damages in the last decades. The evolution of strong cyclones is investigated by simulations with the nonhydrostatic limited area model 'Lokal Modell' (LM) of the German Weather Service (DWD). Which Conditions become important to distinguish an common cyclone from an storm-cyclone? Intense cyclones are mostly characterised by two typical large-scale features: high baroclinicity along the track of the low pressure system and a region of high equivalent potential temperature. For this purpose the observed values of the horizontal temperature gradient and the distribution of air moisture are varied and were used as forcing data, in such a way the development of storms was modified. The forcing data for the LM were generated by the global model of the DWD. Therefore data of real cyclones, such as the low Ginger, which occurred in 2000, were used. As the LM simulates only a limited area, the lateral bounds become problematic because of the manipulated forcing data. A procedure is tested, in order to prevent these problems. In this manner ensembles of storm scenarios were produced. The effects of various conditions were studied. Here in particular the changes in the surface velocity field were of interest. In the case of Ginger, an increase of the temperature gradient about 10 K causes an increasing of the maximum velocity about 3 m/s.

  6. High resolution numerical modeling of mesoscale island wakes and sensitivity to static topographic relief data

    NASA Astrophysics Data System (ADS)

    Nunalee, C. G.; Horváth, Á.; Basu, S.

    2015-03-01

    Recent decades have witnessed a drastic increase in the fidelity of numerical weather prediction (NWP) modeling. Currently, both research-grade and operational NWP models regularly perform simulations with horizontal grid spacings as fine as 1 km. This migration towards higher resolution potentially improves NWP model solutions by increasing the resolvability of mesoscale processes and reducing dependency on empirical physics parameterizations. However, at the same time, the accuracy of high-resolution simulations, particularly in the atmospheric boundary layer (ABL), are also sensitive to orographic forcing which can have significant variability on the same spatial scale as, or smaller than, NWP model grids. Despite this sensitivity, many high resolution atmospheric simulations do not consider uncertainty with respect to selection of static terrain height dataset. In this paper, we use the Weather Research and Forecasting (WRF) model to simulate realistic cases of lower tropospheric flow over and downstream of mountainous islands using both the default global 30 s United States Geographic Survey terrain height dataset (GTOPO30) and the 3 s Shuttle Radar Topography Mission (SRTM) terrain height dataset. Our results demonstrate cases where the differences between GTOPO30-based and SRTM-based model terrain height are significant enough to produce entirely different orographic wake mechanics, such as vortex shedding vs. no vortex shedding. These results are also compared to MODIS visible satellite imagery and highlight the importance of considering uncertain static boundary conditions when running high-resolution mesoscale models.

  7. Mesoscale to plant-scale models of nuclear waste reprocessing.

    SciTech Connect

    Noble, David Frederick; O'Hern, Timothy John; Moffat, Harry K.; Nemer, Martin B.; Domino, Stefan Paul; Rao, Rekha Ranjana; Cipiti, Benjamin B.; Brotherton, Christopher M.; Jove-Colon, Carlos F.; Pawlowski, Roger Patrick

    2010-09-01

    Imported oil exacerabates our trade deficit and funds anti-American regimes. Nuclear Energy (NE) is a demonstrated technology with high efficiency. NE's two biggest political detriments are possible accidents and nuclear waste disposal. For NE policy, proliferation is the biggest obstacle. Nuclear waste can be reduced through reprocessing, where fuel rods are separated into various streams, some of which can be reused in reactors. Current process developed in the 1950s is dirty and expensive, U/Pu separation is the most critical. Fuel rods are sheared and dissolved in acid to extract fissile material in a centrifugal contactor. Plants have many contacts in series with other separations. We have taken a science and simulation-based approach to develop a modern reprocessing plant. Models of reprocessing plants are needed to support nuclear materials accountancy, nonproliferation, plant design, and plant scale-up.

  8. Tight-binding model for materials at mesoscale

    SciTech Connect

    Tai, Yuan-Yen; Choi, Hongchul; Zhu, Wei; Zhu, Jian-Xin

    2016-12-21

    TBM3 is an open source package for computational simulations of quantum materials at multiple scales in length and time. The project originated to investigate the multiferroic behavior in transition-metal oxide heterostructures. The framework has also been designed to study emergent phemona in other quantum materials like 2-dimensional transition-metal dichalcogenides, graphene, topological insulators, and skyrmion in materials, etc. In the long term, we will enable the package for transport and time-resolved phenomena. TBM3 is currently a C++ based numerical tool package and framework for the design and construction of any kind of lattice structures with multi-orbital and spin degrees of freedom. The fortran based portion of the package will be added in the near future. The design of TBM3 is in a highly flexible and reusable framework and the tight-binding parameters can be modeled or informed by DFT calculations. It is currently GPU enabled and feature of CPU enabled MPI will be added in the future.

  9. Meso-scale Modeling of Self-assembly of Polymer-Grafted Nanoparticles

    NASA Astrophysics Data System (ADS)

    Mancini, Derrick; Deshmukh, Sanket; Sankaranarayanan, Subramanian

    2015-03-01

    We develop meso-scale models to explore the self-assembly behavior of polymer-grafted nanoparticles. Specifically, we study nanoparticles with grafts of the thermo-sensitive polymer poly(N-isopropylacrylamide) (PNIPAM), which undergoes a coil-to-globule transition across the LCST at around 305 K. The atomic-scale mechanism of the coil-to-globule transition of polymers grafted nanoparticles and their interactions (agglomeration, assembly behavior) with other particles that are in its vicinity is poorly understood, yet knowledge about these interactions would enable designing novel self-assembled materials with well-defined structural and dynamical properties. Additionally, the effects of chemical nature, geometry, and morphology of the nanoparticle surface on the conformational transition of thermo-sensitive polymers is also unknown. We report on 1) development of all-atom models of polymer-grafted nanoparticles to conduct MD simulations at atomic-levels and 2) perform mesoscopic scaling of the conformational dynamics resulting from the atomistic simulations with the aid of coarse-grained or meso-scale models of PNIPAM and its composites. Coarse-grained simulations allow modeling of larger assemblies of polymer-grafted nanoparticles over longer time scales. This research used resources of the Center for Nanoscale Materials and the Argonne Leadership Computing Facility at Argonne National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract DE-AC02-06CH11357.

  10. Mesoscale/convective interaction

    NASA Technical Reports Server (NTRS)

    Haines, P. A.; Sun, W. Y.

    1988-01-01

    A novel cumulus parameterization scheme (CPS) has been developed in order to account for mesoscale/convective-scale interaction which considers both the mesoscale and convective scale mass and moisture budgets, under the assumption that the heating rate is a maximum for given environmental conditions. The basis of the CPS is a detailed, quasi-one-dimensional cloud model that calculates mass and moisture fluxes similar to those calculated by the Schlesinger (1978) three-dimensional model.

  11. Essays on pricing dynamics, price dispersion, and nested logit modelling

    NASA Astrophysics Data System (ADS)

    Verlinda, Jeremy Alan

    The body of this dissertation comprises three standalone essays, presented in three respective chapters. Chapter One explores the possibility that local market power contributes to the asymmetric relationship observed between wholesale costs and retail prices in gasoline markets. I exploit an original data set of weekly gas station prices in Southern California from September 2002 to May 2003, and take advantage of highly detailed station and local market-level characteristics to determine the extent to which spatial differentiation influences price-response asymmetry. I find that brand identity, proximity to rival stations, bundling and advertising, operation type, and local market features and demographics each influence a station's predicted asymmetric relationship between prices and wholesale costs. Chapter Two extends the existing literature on the effect of market structure on price dispersion in airline fares by modeling the effect at the disaggregate ticket level. Whereas past studies rely on aggregate measures of price dispersion such as the Gini coefficient or the standard deviation of fares, this paper estimates the entire empirical distribution of airline fares and documents how the shape of the distribution is determined by market structure. Specifically, I find that monopoly markets favor a wider distribution of fares with more mass in the tails while duopoly and competitive markets exhibit a tighter fare distribution. These findings indicate that the dispersion of airline fares may result from the efforts of airlines to practice second-degree price discrimination. Chapter Three adopts a Bayesian approach to the problem of tree structure specification in nested logit modelling, which requires a heavy computational burden in calculating marginal likelihoods. I compare two different techniques for estimating marginal likelihoods: (1) the Laplace approximation, and (2) reversible jump MCMC. I apply the techniques to both a simulated and a travel mode

  12. Meso-Scale Modeling to Characterize Moisture Absorption of 3D Woven Composite

    NASA Astrophysics Data System (ADS)

    Yuan, Yuan; Zhou, Chu-wei

    2016-08-01

    For polymer-matrix composites, moisture is expected to degrade their mechanical properties due to matrix plasticization and moisture introduced micro-scale defects. In this study, the moisture absorptions of bulk epoxy, unidirectional composite (UD) and 3D woven composite (3D WC) were tested. Two-stage features have been observed for all these three materials. Moisture properties for UD and 3D WC were found not in simple direct proportion to their matrix volume fractions. The moisture approach of UD was modeled including the effect of fiber/matrix interphase which promotes the moisture uptake. Then, meso-scale FE model for 3D WC was established to characterize the inhomogeneous moisture diffusion. The moisture properties of resin-rich region and fiber bundle in 3D WC were determined from water uptake experiments of bulk epoxy and UD, respectively. Through homogenizing moisture properties of surface and interior weave structures, a simplified theoretical sandwich moisture diffusion approach was established. The moisture weight gains of 3D WC predicted by both meso-scale FE model and simplified sandwich approach were well agreed with the experimental data.

  13. Numerical Weather Prediction Over Caucasus Region With Nested Grid Models

    NASA Astrophysics Data System (ADS)

    Davitashvili, Dr.; Kutaladze, Dr.; Kvatadze, Dr.

    2010-09-01

    Global atmosphere models, which describe the weather processes, give the general character of the weather but can't catch the smaller scale processes, especially local weather for the territories with compound topography. Small-scale processes such as convection often dominate the local weather, which cannot be explicitly represented in models with grid size more then 10 km. A much finer grid is required to properly simulate frontal structures and represent cumulus convection. Georgia lies to the south of the Major Caucasian Ridge and the Lesser Caucasus mountains occupy the southern part of Georgia. About 85 percent of the total land area occupies complex mountain ranges.Therefore for the territory of Georgia it is necessary to use atmosphere models with a very high resolution nested grid system taking into account main orographic features of the area. We have elaborated and configured Whether Research Forecast - Advanced Researcher Weather (WRF-ARW) model for Caucasus region considering geographical-landscape character, topography height, land use, soil type and temperature in deep layers, vegetation monthly distribution, albedo and others. Porting of WRF-ARW application to the grid was a good opportunity for running model on larger number of CPUs and storing large amount of data on the grid storage elements. On the grid WRF was compiled for both Open MP and MPI (Shared + Distributed memory) environment and WPS was compiled for serial environment using PGI (v7.1.6, MPI- version 1.2.7) on the platform Linux-x86. In searching of optimal execution time for time saving different model directory structures and storage schema was used. Simulations were performed using a set of 2 domains with horizontal grid-point resolutions of 15 and 5 km, both defined as those currently being used for operational forecasts The coarser domain is a grid of 94x102 points which covers the South Caucasus region, while the nested inner domain has a grid size of 70x70 points mainly

  14. Propagation of impact-induced shock waves in porous sandstone using mesoscale modeling

    NASA Astrophysics Data System (ADS)

    GÜLdemeister, Nicole; WÜNnemann, Kai; Durr, Nathanael; Hiermaier, Stefan

    2013-01-01

    Abstract-Generation and propagation of shock waves by meteorite impact is significantly affected by material properties such as porosity, water content, and strength. The objective of this work was to quantify processes related to the shock-induced compaction of pore space by numerical <span class="hlt">modeling</span>, and compare the results with data obtained in the framework of the Multidisciplinary Experimental and <span class="hlt">Modeling</span> Impact Research Network (MEMIN) impact experiments. We use <span class="hlt">mesoscale</span> <span class="hlt">models</span> resolving the collapse of individual pores to validate macroscopic (homogenized) approaches describing the bulk behavior of porous and water-saturated materials in large-scale <span class="hlt">models</span> of crater formation, and to quantify localized shock amplification as a result of pore space crushing. We carried out a suite of numerical <span class="hlt">models</span> of planar shock wave propagation through a well-defined area (the "sample") of porous and/or water-saturated material. The porous sample is either represented by a homogeneous unit where porosity is treated as a state variable (macroscale <span class="hlt">model</span>) and water content by an equation of state for mixed material (ANEOS) or by a defined number of individually resolved pores (<span class="hlt">mesoscale</span> <span class="hlt">model</span>). We varied porosity and water content and measured thermodynamic parameters such as shock wave velocity and particle velocity on meso- and macroscales in separate simulations. The <span class="hlt">mesoscale</span> <span class="hlt">models</span> provide additional data on the heterogeneous distribution of peak shock pressures as a consequence of the complex superposition of reflecting rarefaction waves and shock waves originating from the crushing of pores. We quantify the bulk effect of porosity, the reduction in shock pressure, in terms of Hugoniot data as a function of porosity, water content, and strength of a quartzite matrix. We find a good agreement between meso-, macroscale <span class="hlt">models</span> and Hugoniot data from shock experiments. We also propose a combination of a porosity compaction <span class="hlt">model</span> (ɛ-α <span class="hlt">model</span>) that was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..120.3920S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..120.3920S"><span id="translatedtitle">Impact of new aircraft observations Mode-S MRAR in a <span class="hlt">mesoscale</span> NWP <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>Strajnar, B.; Žagar, N.; Berre, L.</p> <p>2015-05-01</p> <p>The impact of recently available high-resolution Mode-S Meteorological Routine Air Report (MRAR) wind and temperature observations is evaluated in the <span class="hlt">mesoscale</span> numerical weather prediction (NWP) <span class="hlt">model</span> Aire Limitée Adaptation dynamique Développement InterNational (ALADIN). Data available from the airspace communicating with the Ljubljana Airport in Slovenia are assimilated by using the three-dimensional variational assimilation procedure on top of all other observations assimilated operationally. A data selection method based on aircraft type was shown to be important for the first application of the new observations in ALADIN. The evaluation of Mode-S MRAR impact included both winter and summer periods. In both seasons a clear improvement of wind and temperature forecasts was found for in the short forecast range, 1-3 h. The impact in the 24 h forecast range depends on season, with a consistent positive improvement of the boundary layer temperature forecasts obtained for the stable anticyclonic winter situations. In summer, the impact was mixed and it was found to be sensitive to the multivariate aspects of the moisture analysis. Overall presented results suggest that the new aircraft-derived observations Mode-S MRAR have a significant potential for <span class="hlt">mesoscale</span> NWP and improved data assimilation <span class="hlt">modeling</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.1154P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.1154P"><span id="translatedtitle">The impact of vertical resolution in <span class="hlt">mesoscale</span> <span class="hlt">model</span> AROME forecasting of radiation fog</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Philip, Alexandre; Bergot, Thierry; Bouteloup, Yves; Bouyssel, François</p> <p>2015-04-01</p> <p>Airports short-term forecasting of fog has a security and economic impact. Numerical simulations have been performed with the <span class="hlt">mesoscale</span> <span class="hlt">model</span> AROME (Application of Research to Operations at <span class="hlt">Mesoscale</span>) (Seity et al. 2011). Three vertical resolutions (60, 90 and 156 levels) are used to show the impact of radiation fog on numerical forecasting. Observations at Roissy Charles De Gaulle airport are compared to simulations. Significant differences in the onset, evolution and dissipation of fog were found. The high resolution simulation is in better agreement with observations than a coarser one. The surface boundary layer and incoming long-wave radiations are better represented. A more realistic behaviour of liquid water content evolution allows a better anticipation of low visibility procedures (ceiling < 60m and/or visibility < 600m). The case study of radiation fog shows that it is necessary to have a well defined vertical grid to better represent local phenomena. A statistical study over 6 months (October 2011 - March 2012 ) using different configurations was carried out. Statistically, results were the same as in the case study of radiation fog. Seity Y., P. Brousseau, S. Malardel, G. Hello, P. Bénard, F. Bouttier, C. Lac, V. Masson, 2011: The AROME-France convective scale operational <span class="hlt">model</span>. Mon.Wea.Rev., 139, 976-991.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10842945','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10842945"><span id="translatedtitle">Assessment of the <span class="hlt">nested</span> grid <span class="hlt">model</span> estimates for driving regional visibility <span class="hlt">models</span> in the southwestern United States.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pai, P; Farber, R J; Karamchandani, P; Tombach, I</p> <p>2000-05-01</p> <p>The <span class="hlt">Nested</span> Grid <span class="hlt">Model</span> (NGM) is a primitive-equation meteorological <span class="hlt">model</span> that is routinely exercised over North America for forecasting purposes by the National Meteorological Center. While prognostic meteorological <span class="hlt">models</span> are being increasingly used to drive air quality <span class="hlt">models</span>, their use in conducting annual simulations requires significant resources. NGM estimates of wind fields and other meteorological variables provide an attractive alternative since they are typically archived and readily available for an entire year. Preliminary evaluation of NGM winds during the summer of 1992 for application to the region surrounding the Grand Canyon National Park showed serious shortcomings. The NGM winds along the borders between California, Arizona and Mexico tend to be northwesterly with a speed of about 6 m/sec, while the observed flow is predominantly southerly at about 2-5 m/sec. The <span class="hlt">mesoscale</span> effect of a thermal low pressure area over the highly heated Southern California and western Arizona deserts does not appear to be represented by the NGM because of its coarse resolution and the use of sparse observations in that region. Tracer simulations and statistical evaluation against special high resolution observations of winds in the southwest United States clearly demonstrate the northwest bias in NGM winds and its adverse effect on predictions of an air quality <span class="hlt">model</span>. The "enhanced" NGM winds, in which selected wind observations are incorporated in the NGM winds using a diagnostic meteorological <span class="hlt">model</span> provide additional confirmation on the primary cause of the northwest bias. This study has demonstrated that in situations where limited resources prevent the use of prognostic meteorological <span class="hlt">models</span>, previously archived coarse resolution wind fields in which additional observations are incorporated to correct known biases provide an attractive option.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A43A3240T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A43A3240T"><span id="translatedtitle">Characterization of <span class="hlt">Mesoscale</span> Variability in WRF - a Coastal Low-Level Jet Case Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tay, K.; Lundquist, J. K.; Skote, M.; Koh, T. Y.</p> <p>2014-12-01</p> <p><span class="hlt">Mesoscale</span> weather <span class="hlt">models</span> have increasingly been featured in wind resource assessment development. The incorporation of real meteorological conditions into such assessments allow a more realistic, physical determination of the wind loads that will be experienced within a wind farm site. Large-Eddy Simulation (LES) confers the advantage of representing finer scale turbulence, such as wake effects. However, <span class="hlt">nesting</span> LES within real <span class="hlt">mesoscale</span> simulations is still in the nascent stage of development. One of the difficulties lies in providing accurate <span class="hlt">mesoscale</span> forcing boundaries for the LES domain. This study aims to characterize the <span class="hlt">mesoscale</span> variability in WRF to lay the groundwork for future <span class="hlt">mesoscale</span>-LES <span class="hlt">nested</span> simulations. A low-level jet (LLJ) event that was observed during the CBLAST-Low 2001 campaign (07 Aug to 09 Aug) provides a robust case study to test the capabilities of and characterize the <span class="hlt">mesoscale</span> variabilities in WRF. The dynamical interaction of a frontal passage with a stable boundary layer over a coastal region makes this an interesting and challenging case for real <span class="hlt">mesoscale</span> simulation and future LES <span class="hlt">nested</span> simulations. Sensitivities to vertical resolution, PBL schemes and initial forcing datasets were tested. This presentation will describe and explain the factors that influence the simulation of this frontal passage and the resulting LLJ. The initial forcing datasets have a major influence on spatial and temporal characteristics, as seen in Figure 1, introducing larger differences than the PBL schemes do. Furthermore, the <span class="hlt">mesoscale</span> simulation also showed a strong dependence on the vertical resolution: increasing the vertical resolution within the atmospheric boundary layer resulted in a more accurate vertical profile for wind speed. Lastly, the simulations did show a dependency on the PBL scheme selected however, the variability between PBL schemes were not large, especially compared to the variability introduced by the boundary and initial</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GMD.....8.2645N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GMD.....8.2645N"><span id="translatedtitle">High-resolution numerical <span class="hlt">modeling</span> of <span class="hlt">mesoscale</span> island wakes and sensitivity to static topographic relief data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nunalee, C. G.; Horváth, Á.; Basu, S.</p> <p>2015-08-01</p> <p>Recent decades have witnessed a drastic increase in the fidelity of numerical weather prediction (NWP) <span class="hlt">modeling</span>. Currently, both research-grade and operational NWP <span class="hlt">models</span> regularly perform simulations with horizontal grid spacings as fine as 1 km. This migration towards higher resolution potentially improves NWP <span class="hlt">model</span> solutions by increasing the resolvability of <span class="hlt">mesoscale</span> processes and reducing dependency on empirical physics parameterizations. However, at the same time, the accuracy of high-resolution simulations, particularly in the atmospheric boundary layer (ABL), is also sensitive to orographic forcing which can have significant variability on the same spatial scale as, or smaller than, NWP <span class="hlt">model</span> grids. Despite this sensitivity, many high-resolution atmospheric simulations do not consider uncertainty with respect to selection of static terrain height data set. In this paper, we use the Weather Research and Forecasting (WRF) <span class="hlt">model</span> to simulate realistic cases of lower tropospheric flow over and downstream of mountainous islands using the default global 30 s United States Geographic Survey terrain height data set (GTOPO30), the Shuttle Radar Topography Mission (SRTM), and the Global Multi-resolution Terrain Elevation Data set (GMTED2010) terrain height data sets. While the differences between the SRTM-based and GMTED2010-based simulations are extremely small, the GTOPO30-based simulations differ significantly. Our results demonstrate cases where the differences between the source terrain data sets are significant enough to produce entirely different orographic wake mechanics, such as vortex shedding vs. no vortex shedding. These results are also compared to MODIS visible satellite imagery and ASCAT near-surface wind retrievals. Collectively, these results highlight the importance of utilizing accurate static orographic boundary conditions when running high-resolution <span class="hlt">mesoscale</span> <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ems..confE.264R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ems..confE.264R"><span id="translatedtitle">Coupling of the atmospheric <span class="hlt">mesoscale</span> <span class="hlt">model</span> FOOT3DK to a photosynthesis <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>Reyers, M.; Zacharias, S.; Kerschgens, M.</p> <p>2009-09-01</p> <p>The interdisciplinary project SFB Transregio 32 aims at monitoring and <span class="hlt">modelling</span> of patterns in soil-vegetation-atmosphere systems. Field and aircraft measurements show temporal and spatial small scale variability of CO2 and H2O fluxes, which are associated with small scale vegetation structures of varying photosynthetic activity. Within the subproject D1 of the SFB Transregio 32 the influence of surface heterogenities on atmospheric fluxes is simulated using the atmospheric <span class="hlt">mesoscale</span> <span class="hlt">model</span> FOOT3DK. Simulations are performed for the TR32 investigation area near Selhausen, located in North-Rhine-Westphalia, Germany, with a horizontal resolution up to 100 m. Since in the original <span class="hlt">model</span> set-up no carbon cycle is included, FOOT3DK is coupled to a photosynthesis <span class="hlt">model</span>, which consists of a C3 single-leaf <span class="hlt">model</span> following Farquhar et al. (1980). Big-leaf approaches tend to overestimate photosynthesis activity, therefore an extended big-leaf <span class="hlt">model</span> (de Pury and Farquhar, 1997) is used for the upscaling from leaf to canopy scale. In this so-called sun/shade <span class="hlt">model</span> the canopy is divided into sunlit and shaded fractions and the net CO2 fluxes are calculated for both fractions separately. For the validation simulations with the stand-alone version of the photosynthesis <span class="hlt">model</span> are compared with field measurements for wheat and sugarbeet. Despite some slight overestimations simulated CO2 fluxes exhibit a good overall agreement with measured values. The general diurnal variation as well as local extrema (e.g. caused by clouds) are reproduced well. High resolution simulations of the coupled FOOT3DK-photosynthesis <span class="hlt">model</span> show reasonable results. While the diurnal cycle is matched well, the magnitudes of the simulated CO2 fluxes are considerably overestimated compared to measurements. The overestimations are probably caused by the ratio of photosynthetic active radiation to incoming solar radiation, which currently is assumed to be constant. To investigate the influence of small scale</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('http://hdl.handle.net/2060/20010037609','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010037609"><span id="translatedtitle">A Study of Heavy Precipitation Events in Taiwan During 10-13 August, 1994. Part 2; <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tao, Wei Kuo; Chen, C.-S.; Jia, Y.; Baker, D.; Lang, S.; Wetzel, P.; Lau, W. K.-M.</p> <p>2001-01-01</p> <p>Several heavy precipitation episodes occurred over Taiwan from August 10 to 13, 1994. Precipitation patterns and characteristics are quite different between the precipitation events that occurred from August 10 and I I and from August 12 and 13. In Part I (Chen et al. 2001), the environmental situation and precipitation characteristics are analyzed using the EC/TOGA data, ground-based radar data, surface rainfall patterns, surface wind data, and upper air soundings. In this study (Part II), the Penn State/NCAR <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> (MM5) is used to study the precipitation characteristics of these heavy precipitation events. Various physical processes (schemes) developed at NASA Goddard Space Flight Center (i.e., cloud microphysics scheme, radiative transfer <span class="hlt">model</span>, and land-soil-vegetation surface <span class="hlt">model</span>) have recently implemented into the MM5. These physical packages are described in the paper, Two way interactive <span class="hlt">nested</span> grids are used with horizontal resolutions of 45, 15 and 5 km. The <span class="hlt">model</span> results indicated that Cloud physics, land surface and radiation processes generally do not change the location (horizontal distribution) of heavy precipitation. The Goddard 3-class ice scheme produced more rainfall than the 2-class scheme. The Goddard multi-broad-band radiative transfer <span class="hlt">model</span> reduced precipitation compared to a one-broad band (emissivity) radiation <span class="hlt">model</span>. The Goddard land-soil-vegetation surface <span class="hlt">model</span> also reduce the rainfall compared to a simple surface <span class="hlt">model</span> in which the surface temperature is computed from a Surface energy budget following the "force-re store" method. However, <span class="hlt">model</span> runs including all Goddard physical processes enhanced precipitation significantly for both cases. The results from these runs are in better agreement with observations. Despite improved simulations using different physical schemes, there are still some deficiencies in the <span class="hlt">model</span> simulations. Some potential problems are discussed. Sensitivity tests (removing either terrain or radiative</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880060530&hterms=pea&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dpea','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880060530&hterms=pea&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dpea"><span id="translatedtitle"><span class="hlt">Mesoscale</span> spiral vortex embedded within a Lake Michigan snow squall band - High resolution satellite observations and numerical <span class="hlt">model</span> simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lyons, Walter A.; Keen, Cecil S.; Hjelmfelt, Mark; Pease, Steven R.</p> <p>1988-01-01</p> <p>It is known that Great Lakes snow squall convection occurs in a variety of different modes depending on various factors such as air-water temperature contrast, boundary-layer wind shear, and geostrophic wind direction. An exceptional and often neglected source of data for <span class="hlt">mesoscale</span> cloud studies is the ultrahigh resolution multispectral data produced by Landsat satellites. On October 19, 1972, a clearly defined spiral vortex was noted in a Landsat-1 image near the southern end of Lake Michigan during an exceptionally early cold air outbreak over a still very warm lake. In a numerical simulation using a three-dimensional Eulerian hydrostatic primitive equation <span class="hlt">mesoscale</span> <span class="hlt">model</span> with an initially uniform wind field, a definite analog to the observed vortex was generated. This suggests that intense surface heating can be a principal cause in the development of a low-level <span class="hlt">mesoscale</span> vortex.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRC..112.3S14C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRC..112.3S14C"><span id="translatedtitle">Simulation and characterization of the Adriatic Sea <span class="hlt">mesoscale</span> variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cushman-Roisin, Benoit; Korotenko, Konstantin A.; Galos, Camelia E.; Dietrich, David E.</p> <p>2007-03-01</p> <p>This paper presents simulations of the Adriatic Sea using the DieCAST <span class="hlt">model</span> applied on a 1.2-min grid (about 2-km resolution). The simulations resolve the <span class="hlt">mesoscale</span> variability because the grid size falls below the first baroclinic deformation radius (about 5-10 km) and DieCAST has very low horizontal dissipation. The <span class="hlt">model</span> is initialized with seasonally averaged temperature and salinity data and forced with climatological winds and surface buoyancy fluxes (both heat flux and evaporation minus precipitation). River discharges are varied daily according to a perpetual year for every river, and the open-boundary conditions at Otranto Strait are obtained by <span class="hlt">nesting</span> in two larger-scale <span class="hlt">models</span>. The present simulations demonstrate that the DieCAST <span class="hlt">model</span> allows <span class="hlt">mesoscale</span> instabilities to develop at length scales of 5-20 km and over time scales of a few days. The simulated variability exhibits pronounced similarities with the actual <span class="hlt">mesoscale</span> variability, in terms of location, nature and temporal evolution of the features. Meanders, swirls and eddies are noted along the relatively smooth Italian coast while offshore jets and filaments better describe the <span class="hlt">mesoscale</span> activity along the more rugged coast of Croatia. In sum, DieCAST is highly suitable for the study of <span class="hlt">mesoscale</span> variability in the Adriatic Sea. The present simulations also show that the seasonal hydrography of the Adriatic Sea is intrinsically unstable to <span class="hlt">mesoscale</span> perturbations, and that the <span class="hlt">mesoscale</span> variability along the Italian coast is the result of baroclinic instability of the Western Adriatic Current. It is shown how the properties of this instability are related to the local bottom topography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JChPh.135j4105G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JChPh.135j4105G"><span id="translatedtitle">Local pressure components and surface tension of spherical interfaces. Thermodynamic versus mechanical definitions. I. A <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> of droplets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ghoufi, Aziz; Malfreyt, Patrice</p> <p>2011-09-01</p> <p>We report <span class="hlt">mesoscale</span> simulations of spherical drops to investigate the surface tension and mechanical properties. The Monte Carlo simulations are performed with the multibody potential commonly used in the many-body dissipative particle dynamics simulations. We establish here the calculation of the local normal and transverse components of the pressure tensor via the perturbation volume within the thermodynamic route. The different profiles of these components are compared to those calculated using the mechanical approach. To complete the <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> of drops, we investigate the curvature dependence of the surface tension in order to calculate the Tolman's length, which is found to be negative.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Geomo.256...68V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Geomo.256...68V"><span id="translatedtitle">Simulating <span class="hlt">mesoscale</span> coastal evolution for decadal coastal management: A new framework integrating multiple, complementary <span class="hlt">modelling</span> approaches</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Maanen, Barend; Nicholls, Robert J.; French, Jon R.; Barkwith, Andrew; Bonaldo, Davide; Burningham, Helene; Brad Murray, A.; Payo, Andres; Sutherland, James; Thornhill, Gillian; Townend, Ian H.; van der Wegen, Mick; Walkden, Mike J. A.</p> <p>2016-03-01</p> <p>Coastal and shoreline management increasingly needs to consider morphological change occurring at decadal to centennial timescales, especially that related to climate change and sea-level rise. This requires the development of morphological <span class="hlt">models</span> operating at a <span class="hlt">mesoscale</span>, defined by time and length scales of the order 101 to 102 years and 101 to 102 km. So-called 'reduced complexity' <span class="hlt">models</span> that represent critical processes at scales not much smaller than the primary scale of interest, and are regulated by capturing the critical feedbacks that govern landform behaviour, are proving effective as a means of exploring emergent coastal behaviour at a landscape scale. Such <span class="hlt">models</span> tend to be computationally efficient and are thus easily applied within a probabilistic framework. At the same time, reductionist <span class="hlt">models</span>, built upon a more detailed description of hydrodynamic and sediment transport processes, are capable of application at increasingly broad spatial and temporal scales. More qualitative <span class="hlt">modelling</span> approaches are also emerging that can guide the development and deployment of quantitative <span class="hlt">models</span>, and these can be supplemented by varied data-driven <span class="hlt">modelling</span> approaches that can achieve new explanatory insights from observational datasets. Such disparate approaches have hitherto been pursued largely in isolation by mutually exclusive <span class="hlt">modelling</span> communities. Brought together, they have the potential to facilitate a step change in our ability to simulate the evolution of coastal morphology at scales that are most relevant to managing erosion and flood risk. Here, we advocate and outline a new integrated <span class="hlt">modelling</span> framework that deploys coupled <span class="hlt">mesoscale</span> reduced complexity <span class="hlt">models</span>, reductionist coastal area <span class="hlt">models</span>, data-driven approaches, and qualitative conceptual <span class="hlt">models</span>. Integration of these heterogeneous approaches gives rise to <span class="hlt">model</span> compositions that can potentially resolve decadal- to centennial-scale behaviour of diverse coupled open coast, estuary and inner</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IzAOP..52..560D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IzAOP..52..560D"><span id="translatedtitle"><span class="hlt">Modeling</span> meso- and sub-<span class="hlt">mesoscale</span> circulation along the eastern Crimean coast using numerical calculations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Demyshev, S. G.; Evstigneeva, N. A.</p> <p>2016-09-01</p> <p>A numerical experiment has been carried out using a hydrodynamical <span class="hlt">model</span> with nonlinear equations of motion and heat and salt advection to reconstruct the fields of hydrophysical parameters taking into account the real atmospheric forcing for the autumn season along the southern coast of the Crimean Peninsula. The studied part of the coast is situated at 44.25°N 33.95°E/44.72°N 34.55°E. High spatial resolution is used for <span class="hlt">modeling</span>: 350 m in the horizontal plane with 38 layers in the vertical; the bottom topography is described in detail with 500 m resolution. Detected and studied meso- and sub-<span class="hlt">mesoscale</span> structures in the current field agree well with the observational data, which is impossible or hard to identify in numerical experiments with coarser resolution. Their kinematic characteristics and the lifetime are defined and some mechanisms of their origin are suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870024426&hterms=static+dynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dstatic%2Bdynamic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870024426&hterms=static+dynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dstatic%2Bdynamic"><span id="translatedtitle">Dynamic and static initialization of a <span class="hlt">mesoscale</span> <span class="hlt">model</span> using VAS satellite data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Beauchamp, J. G.; Warner, T. T.</p> <p>1985-01-01</p> <p>Various <span class="hlt">mesoscale</span> weather forecast <span class="hlt">model</span> initialization procedures were tested in seven simulation forecasts for a 12 hr period in July 1981. Attention was given to the impacts of using as input radiosonde data, VISSR Atmospheric Sounder (VAS) data and a combination of VAS and data from a smoothed global analysis. The data were assimilated with successive correction objective analysis procedures. The <span class="hlt">model</span> had a 60 km horizontal grid-length resolution, 14 layers in the vertical, and accounted for short- and long-wave energy in the surface energy budget but not in the atmosphere. Conventional data were used for the mass and moisture fields. The trials showed that VAS data enhanced the predictions of the temperature and mass variables, while winds were least accurately predicted when VAS data were entered in the initializations. Finally, statically initialized precipitation forecasts from radiosonde and/or VAS data exhibited equal skill.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcMod.111....1M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcMod.111....1M"><span id="translatedtitle">The dependence of the ocean's MOC on <span class="hlt">mesoscale</span> eddy diffusivities: 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>Marshall, John; Scott, Jeffery R.; Romanou, Anastasia; Kelley, Maxwell; Leboissetier, Anthony</p> <p>2017-03-01</p> <p>The dependence of the depth and strength of the ocean's global meridional overturning cells (MOC) on the specification of <span class="hlt">mesoscale</span> eddy diffusivity (K) is explored in two ocean <span class="hlt">models</span>. The GISS and MIT ocean <span class="hlt">models</span> are driven by the same prescribed forcing fields, configured in similar ways, spun up to equilibrium for a range of K's and the resulting MOCs mapped and documented. Scaling laws implicit in modern theories of the MOC are used to rationalize the results. In all calculations the K used in the computation of eddy-induced circulation and that used in the representation of eddy stirring along neutral surfaces, is set to the same value but is changed across experiments. We are able to connect changes in the strength and depth of the Atlantic MOC, the southern ocean upwelling MOC, and the deep cell emanating from Antarctica, to changes in K.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1222552','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1222552"><span id="translatedtitle">A creep-damage <span class="hlt">model</span> for <span class="hlt">mesoscale</span> simulations of concrete expansion-degradation phenomena</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Giorla, Alain B; Le Pape, Yann</p> <p>2015-01-01</p> <p>Long-term performance of aging concrete in nuclear power plants (NPPs) requires a careful examination of the physical phenomena taking place in the material. Concrete under high neutron irradiation is subjected to large irreversible deformations as well as mechanical damage, caused by a swelling of the aggregates. However, these results, generally obtained in accelerated conditions in test reactors, cannot be directly applied to NPP irradiated structures, i.e., the biological shield, operating conditions due to difference in time scale and environmental conditions (temperature, humidity). <span class="hlt">Mesoscale</span> numerical simulations are performed to separate the underlying mechanisms and their interactions. The cement paste creep-damage <span class="hlt">model</span> accounts for the effect of the loading rate on the apparent damage properties of the material and uses an event-based approach to capture the competition between creep and damage. The <span class="hlt">model</span> is applied to the simulation of irradiation experiments from the literature and shows a good agreement with the experimental data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170001444&hterms=oceans&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Doceans','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170001444&hterms=oceans&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Doceans"><span id="translatedtitle">The dependence of the oceans MOC on <span class="hlt">mesoscale</span> eddy diffusivities: A <span class="hlt">model</span> study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Marshall, John; Scott, Jeffery R.; Romanou, Anastasia; Kelley, Maxwell; Leboissetier, Anthony</p> <p>2017-01-01</p> <p>The dependence of the depth and strength of the ocean's global meridional overturning cells (MOC) on the specification of <span class="hlt">mesoscale</span> eddy diffusivity (K) is explored in two ocean <span class="hlt">models</span>. The GISS and MIT ocean <span class="hlt">models</span> are driven by the same prescribed forcing fields, configured in similar ways, spun up to equilibrium for a range of K 's and the resulting MOCs mapped and documented. Scaling laws implicit in modern theories of the MOC are used to rationalize the results. In all calculations the K used in the computation of eddy-induced circulation and that used in the representation of eddy stirring along neutral surfaces, is set to the same value but is changed across experiments. We are able to connect changes in the strength and depth of the Atlantic MOC, the southern ocean upwelling MOC, and the deep cell emanating from Antarctica, to changes in K.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000MeApp...7..193A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000MeApp...7..193A"><span id="translatedtitle">The impact of observations on <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> forecasts of three-hourly rainfall accumulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, S. R.; Graham, R. J.; Bader, M. J.</p> <p>2000-09-01</p> <p>The aim of data-impact studies at the UK Met. Office is to investigate how observations affect the accuracy of <span class="hlt">model</span> forecasts. Results from such experiments provide useful evidence on which to base the design of observational networks. This project, using a case study approach, investigated the relative benefit of different observation types within The Met. Office's <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> domain on forecasts of three-hourly precipitation accumulation over the UK up to 12 hours ahead. The method used assesses the impact of assimilating single observation types, or a limited combination of types, where impact is measured against a control forecast obtained after a dummy assimilation using no observations. In experiments for 13 case studies, the observation types that most frequently provided a beneficial impact when presented alone to the assimilation were sonde data, surface data and data from the Moisture Observation Processing System (MOPS).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1121927','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1121927"><span id="translatedtitle">LDRD final report : <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> of dynamic loading of heterogeneous materials.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Robbins, Joshua; Dingreville, Remi Philippe Michel; Voth, Thomas Eugene; Furnish, Michael David</p> <p>2013-12-01</p> <p>Material response to dynamic loading is often dominated by microstructure (grain structure, porosity, inclusions, defects). An example critically important to Sandia's mission is dynamic strength of polycrystalline metals where heterogeneities lead to localization of deformation and loss of shear strength. Microstructural effects are of broad importance to the scientific community and several institutions within DoD and DOE; however, current <span class="hlt">models</span> rely on inaccurate assumptions about mechanisms at the sub-continuum or <span class="hlt">mesoscale</span>. Consequently, there is a critical need for accurate and robust methods for <span class="hlt">modeling</span> heterogeneous material response at this lower length scale. This report summarizes work performed as part of an LDRD effort (FY11 to FY13; project number 151364) to meet these needs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.A33B0157L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.A33B0157L"><span id="translatedtitle">Impact of data assimilation on Chukchi/Beaufort Seas <span class="hlt">mesoscale</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>Liu, F.; Krieger, J.; Zhang, J.</p> <p>2010-12-01</p> <p>Offshore development in the Chukchi/Beaufort Seas requires an improved understanding of the surface wind field, a crucial parameter for assessing and predicting dispersal and movement of oil spills. A study has thus been established to investigate the <span class="hlt">mesoscale</span> features of the surface wind field throughout this region. In this study, we focus on investigating the impact of data assimilation on the simulation of the Chukchi/Beaufort Seas <span class="hlt">mesoscale</span> surface wind field with the Weather Research and Forecasting <span class="hlt">model</span> (WRF) and its variational data assimilation system (WRF-Var). In the application of WRF-Var, <span class="hlt">model</span> background error (BE) is a key element required for the assimilation procedure. We have conducted an investigation into how varying the <span class="hlt">model</span> background error affects the results of assimilating in-situ surface observations. The background error covariances we tested include CV3 (a built-in global BE file in WRF-Var) and several domain-dependent CV5 BE files. The latter were calculated using 12-hourly forecast results and 24-hourly forecast over 2-month and 1-year periods, followed by the calculation of separate BE at 00, 06, 12, and 18 UTC, in order to capture the diurnal variation of the <span class="hlt">model</span> background error. The results show that the customized domain-dependent BE produces much better assimilation results than the global CV3 BE, and the CV5 BE calculated over a 1-year period additionally helps to improve the assimilation. When the diurnal variation of background error was included in the CV5 BE, a further improvement was achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27709956','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27709956"><span id="translatedtitle"><span class="hlt">Modeling</span> the Formation of Alkali Aluminosilicate Gels at the <span class="hlt">Mesoscale</span> Using Coarse-Grained Monte Carlo.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yang, Kengran; White, Claire E</p> <p>2016-11-08</p> <p>Alkali-activated materials (AAMs) are currently being pursued as viable alternatives to conventional ordinary Portland cement because of their lower carbon footprint and established mechanical performance. However, our understanding of the <span class="hlt">mesoscale</span> morphology (∼1 to 100 nm) of AAMs and related amorphous aluminosilicate gels, including the development of the three-dimensional aluminosilicate network and nanoscale porosity, is severely limited. This study investigates the structural changes that occur during the formation of AAM gels at the <span class="hlt">mesoscale</span> by utilizing a coarse-grained Monte Carlo (CGMC) <span class="hlt">modeling</span> technique that exploits density functional theory calculations. The <span class="hlt">model</span> is capable of simulating the reaction of an aluminosilicate particle in a highly alkaline solution (sodium hydroxide or sodium silicate). Two precursor morphologies have been investigated (layered alumina and silica sheets mimicking metakaolin and spherical aluminosilicate particles reminiscent of coal-derived fly ash) to determine if the precursor morphology has an impact on the structural evolution of the resulting alkali-activated aluminosilicate gel. The CGMC <span class="hlt">model</span> can capture the three major stages of the alkali-activation process-dissolution, polycondensation, and reorganization-revealing that the dissolved silicate and aluminate species, ranging from monomers to nanoprecipitates (100s of monomers in size), exist in the pore solution of the hardened gel. The <span class="hlt">model</span> also reveals that the silica concentration of the activating solution controls the extent of dissolution of the precursor particle. From the analysis of the aluminosilicate cluster size distributions, the mechanisms of AAM gel growth have been elucidated, revealing that Ostwald ripening occurs in systems containing free silica at the start of the reaction. On the other hand, growth of the hydroxide-activated systems (metakaolin and fly ash) occurs via the formation of intermediate-sized clusters in addition to continual</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=146423&keyword=Michael+AND+Freeman&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=78124598&CFTOKEN=71577572','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=146423&keyword=Michael+AND+Freeman&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=78124598&CFTOKEN=71577572"><span id="translatedtitle">EXPERIMENTAL AND <span class="hlt">MODEL</span>-COMPUTED AREA AVERAGED VERTICAL PROFILES OF WIND SPEED FOR EVALUATION OF <span class="hlt">MESOSCALE</span> URBAN CANOPY SCHEMES</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>Numerous urban canopy schemes have recently been developed for <span class="hlt">mesoscale</span> <span class="hlt">models</span> in order to approximate the drag and turbulent production effects of a city on the air flow. However, little data exists by which to evaluate the efficacy of the schemes since "area-averaged&quo...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028853','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028853"><span id="translatedtitle">Determinants of wood thrush <span class="hlt">nest</span> success: A multi-scale, <span class="hlt">model</span> selection approach</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Driscoll, M.J.L.; Donovan, T.; Mickey, R.; Howard, A.; Fleming, K.K.</p> <p>2005-01-01</p> <p>We collected data on 212 wood thrush (Hylocichla mustelina) <span class="hlt">nests</span> in central New York from 1998 to 2000 to determine the factors that most strongly influence <span class="hlt">nest</span> success. We used an information-theoretic approach to assess and rank 9 <span class="hlt">models</span> that examined the relationship between <span class="hlt">nest</span> success (i.e., the probability that a <span class="hlt">nest</span> would successfully fledge at least 1 wood thrush offspring) and habitat conditions at different spatial scales. We found that 4 variables were significant predictors of <span class="hlt">nesting</span> success for wood thrushes: (1) total core habitat within 5 km of a study site, (2) distance to forest-field edge, (3) total forest cover within 5 km of the study site, and (4) density and variation in diameter of trees and shrubs surrounding the <span class="hlt">nest</span>. The coefficients of these predictors were all positive. Of the 9 <span class="hlt">models</span> evaluated, amount of core habitat in the 5-km landscape was the best-fit <span class="hlt">model</span>, but the vegetation structure <span class="hlt">model</span> (i.e., the density of trees and stems surrounding a <span class="hlt">nest</span>) was also supported by the data. Based on AIC weights, enhancement of core area is likely to be a more effective management option than any other habitat-management options explored in this study. Bootstrap analysis generally confirmed these results; core and vegetation structure <span class="hlt">models</span> were ranked 1, 2, or 3 in over 50% of 1,000 bootstrap trials. However, bootstrap results did not point to a decisive <span class="hlt">model</span>, which suggests that multiple habitat factors are influencing wood thrush <span class="hlt">nesting</span> success. Due to <span class="hlt">model</span> uncertainty, we used a <span class="hlt">model</span> averaging approach to predict the success or failure of each <span class="hlt">nest</span> in our dataset. This averaged <span class="hlt">model</span> was able to correctly predict 61.1% of <span class="hlt">nest</span> outcomes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20010072133&hterms=assimilation+procedure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dassimilation%2Bprocedure','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20010072133&hterms=assimilation+procedure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dassimilation%2Bprocedure"><span id="translatedtitle">Assimilation of Combined Microwave and Lightning Measurement in a <span class="hlt">Mesoscale</span> Weather Prediction <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>Chang, Dong-Eon; Weinman, James A.; Busalacchi, Antonio J. (Technical Monitor)</p> <p>2000-01-01</p> <p>Intermittent measurements of precipitation and integrated water vapor (IWV) distributions were retrieved from the Special Sensor Microwave/Imager (SSM/I) and Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) radiometers. Lightning generates very low frequency (VLF) radio noise pulses called sferics. Those pulses propagate over large distances so that they can be continuously monitored with a sparse network of ground based radio receivers. Sferics data, tuned with intermittent spaceborne microwave radiometer data, were used to generate estimated rainfall that was assimilated into a <span class="hlt">mesoscale</span> weather prediction <span class="hlt">model</span>. Both continuous latent heating adjustment and a variational technique are applied as assimilation procedures to evaluate the impact of lightning observations on the forecast of an intense winter squall line over the Gulf of Mexico. Sensitivities to the assimilation of additional measurements such as IWV and sea surface temperature (SST), and measurement errors will also be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MolPh.113..898M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MolPh.113..898M"><span id="translatedtitle">Mucin aggregation from a rod-like <span class="hlt">meso-scale</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>Moreno, Nicolas; Perilla, Jairo E.; Colina, Coray M.; Lísal, Martin</p> <p>2015-05-01</p> <p>Dissipative particle dynamics, a <span class="hlt">meso-scale</span> particle-based <span class="hlt">model</span>, was used to study the aggregation of mucins in aqueous solutions. Concentration, strength of the mucin-water interactions, as well as the effects of size, shape, and composition of the <span class="hlt">model</span> molecules were studied. <span class="hlt">Model</span> proteins were represented as rod-like objects formed by coarse-grained beads. In the first <span class="hlt">model</span>, only one type of beads formed the mucin. It was found that all the surfaces were available to form aggregates and the conformation of the aggregates was a function of the strength of the mucin-water interaction. With this <span class="hlt">model</span>, the number of aggregates was unaffected by the initial position of the mucins in the simulation box, except for the lowest mucin concentration. In a more refined mucin <span class="hlt">model</span>, two kinds of beads were used in the molecule in order to represent the existence of cysteine-like terminal groups in the actual molecule. With this new scheme, aggregation took place by the interaction of the terminal groups between <span class="hlt">model</span> molecules. The kinetic analysis of the evolution of the number of aggregates with time was also studied for both mucin <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5879503','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5879503"><span id="translatedtitle">MELSAR: a <span class="hlt">mesoscale</span> air quality <span class="hlt">model</span> for complex terrain. Volume 2. Appendices</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Allwine, K.J.; Whiteman, C.D.</p> <p>1985-04-01</p> <p>This final report is submitted as part of the Green River Ambient <span class="hlt">Model</span> Assessment (GRAMA) project conducted at the US Department of Energy's Pacific Northwest Laboratory for the US Environmental Protection Agency. The GRAMA Program has, as its ultimate goal, the development of validated air quality <span class="hlt">models</span> that can be applied to the complex terrain of the Green River Formation of western Colorado, eastern Utah and southern Wyoming. The Green River Formation is a geologic formation containing large reserves of oil shale, coal, and other natural resources. Development of these resources may lead to a degradation of the air quality of the region. Air quality <span class="hlt">models</span> are needed immediately for planning and regulatory purposes to assess the magnitude of these regional impacts. This report documents one of the <span class="hlt">models</span> being developed for this purpose within GRAMA - specifically a <span class="hlt">model</span> to predict short averaging time (less than or equal to 24 h) pollutant concentrations resulting from the <span class="hlt">mesoscale</span> transport of pollutant releases from multiple sources. MELSAR has not undergone any rigorous operational testing, sensitivity analyses, or validation studies. Testing and evaluation of the <span class="hlt">model</span> are needed to gain a measure of confidence in the <span class="hlt">model</span>'s performance. This report consists of two volumes. This volume contains the Appendices, which include listings of the FORTRAN code and Volume 1 contains the <span class="hlt">model</span> overview, technical description, and user's guide. 13 figs., 10 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004ACPD....4.5455L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004ACPD....4.5455L"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> of combined aerosol and photo-oxidant processes in the eastern Mediterranean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lazaridis, M.; Spyridaki, A.; Solberg, S.; Smolík, J.; Ždímal, V.; Eleftheriadis, K.; Aleksandropoulou, V.; Hov, O.; Georgopoulos, P. G.</p> <p>2004-09-01</p> <p>Particulate matter and photo-oxidant processes in the Eastern Mediterranean have been studied using the UAM-AERO <span class="hlt">mesoscale</span> air quality <span class="hlt">model</span> in conjunction with the NILU-CTM regional <span class="hlt">model</span>. Meteorological data were obtained from the RAMS prognostic meteorological <span class="hlt">model</span>. The <span class="hlt">modeling</span> domain includes the eastern Mediterranean area between the Greek mainland and the island of Crete. The <span class="hlt">modeling</span> system is applied to study the atmospheric processes in three periods, i.e. 13-16 July 2000, 26-30 July 2000 and 7-14 January 2001. The spatial and temporal distributions of both gaseous and particulate matter pollutants have been extensively studied together with the identification of major emission sources in the area. The <span class="hlt">modeling</span> results were compared with field data obtained in the same period. Comparison of the <span class="hlt">modeling</span> results with measured data was performed for a number of gaseous and aerosol species. The UAM-AERO <span class="hlt">model</span> underestimates the PM10 measured concentrations during summer but better comparison has been obtained for the winter data.</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://hdl.handle.net/2060/20150002902','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002902"><span id="translatedtitle">High-Resolution <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Setup for the Eastern Range and Wallops Flight Facility</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Watson, Leela R.; Zavodsky, Bradley T.</p> <p>2015-01-01</p> <p><span class="hlt">Mesoscale</span> weather conditions can have an adverse effect on space launch, landing, ground processing, and weather advisories, watches, and warnings at the Eastern Range (ER) in Florida and Wallops Flight Facility (WFF) in Virginia. During summer, land-sea interactions across Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) lead to sea breeze front formation, which can spawn deep convection that can hinder operations and endanger personnel and resources. Many other weak locally-driven low-level boundaries and their interactions with the sea breeze front and each other can also initiate deep convection in the KSC/CCAFS area. These convective processes often last 60 minutes or less and pose a significant challenge to the local forecasters. Surface winds during the transition seasons (spring and fall) pose the most difficulties for the forecasters at WFF. They also encounter problems forecasting convective activity and temperature during those seasons. Therefore, accurate <span class="hlt">mesoscale</span> <span class="hlt">model</span> forecasts are needed to better forecast a variety of unique weather phenomena. Global and national scale <span class="hlt">models</span> cannot properly resolve important local-scale weather features at each location due to their horizontal resolutions being much too coarse. Therefore, a properly tuned local data assimilation (DA) and forecast <span class="hlt">model</span> at a high resolution is needed to provide improved capability. To accomplish this, a number of sensitivity tests were performed using the Weather Research and Forecasting (WRF) <span class="hlt">model</span> in order to determine the best DA/<span class="hlt">model</span> configuration for operational use at each of the space launch ranges to best predict winds, precipitation, and temperature. A set of Perl scripts to run the Gridpoint Statistical Interpolation (GSI)/WRF in real-time were provided by NASA's Short-term Prediction Research and Transition Center (SPoRT). The GSI can analyze many types of observational data including satellite, radar, and conventional data. The GSI/WRF scripts</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.2729C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.2729C"><span id="translatedtitle">What can we learn from the hydrological <span class="hlt">modeling</span> of small-scale catchments for the discharge and water balance <span class="hlt">modeling</span> of <span class="hlt">mesoscale</span> catchments?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cornelissen, Thomas; Diekkrüger, Bernd; Bogena, Heye</p> <p>2015-04-01</p> <p>The application of 3D hydrological <span class="hlt">models</span> remains a challenge both in research and application studies because the parameterization not only depends on the amount and quality of data available for calibration and validation but also on the spatial and temporal <span class="hlt">model</span> resolution. In recent years, the <span class="hlt">model</span> parameterization has improved with the availability of high resolution data (e.g. eddy-covariance, wireless soil sensor networks). Unfortunately, these high resolution data are typically only available for small scale research test sites. This study aims to upscale the parameterization from a highly equipped, small-scale catchment to a <span class="hlt">mesoscale</span> catchment in order to reduce the parameterization uncertainty at that scale. The two <span class="hlt">nested</span> catchments chosen for the study are the 0.38 km² large spruce covered Wüstebach catchment and the 42 km² large Erkensruhr catchment characterized by a mixture of spruce and beech forest and grassland vegetation. The 3D hydrogeological <span class="hlt">model</span> HydroGeoSphere (HGS) has already been setup for the Wüstebach catchment in a previous study with a focus on the simulation performance of soil water dynamics and patterns. Thus, the parameterization process did not only optimize the water balance components but the catchment's wireless soil sensor network data were utilized to calibrate porosities in order to improve the simulation of soil moisture dynamics. In this study we compared different HGS <span class="hlt">model</span> realizations for the Erkensruhr catchment with different input data. For the first <span class="hlt">model</span> realization, the catchment is treated heterogeneous in terms of soil properties and topography but homogeneous with respect to land use, precipitation and potential evapotranspiration. For this case, the spruce forest parameterization and the climate input data were taken directly from the small-scale Wüstebach <span class="hlt">model</span> realization. Next, the calibrated soil porosity for the Wüstebach catchment is applied to the Erkensruhr. Further <span class="hlt">model</span> realizations</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150000384','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150000384"><span id="translatedtitle">Range-Specific High-Resolution <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Setup: Data Assimilation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Watson, Leela R.</p> <p>2014-01-01</p> <p><span class="hlt">Mesoscale</span> weather conditions can have an adverse effect on space launch, landing, and ground processing at the Eastern Range (ER) in Florida and Wallops Flight Facility (WFF) in Virginia. During summer, land-sea interactions across Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) lead to sea breeze front formation, which can spawn deep convection that can hinder operations and endanger personnel and resources. Many other weak locally driven low-level boundaries and their interactions with the sea breeze front and each other can also initiate deep convection in the KSC/CCAFS area. Some of these other boundaries include the Indian River breeze front, Banana River breeze front, outflows from previous convection, horizontal convective rolls, convergence lines from other inland bodies of water such as Lake Okeechobee, the trailing convergence line from convergence of sea breeze fronts due to the shape of Cape Canaveral, frictional convergence lines from the islands in the Bahamas, convergence lines from soil moisture differences, convergence lines from cloud shading, and others. All these subtle weak boundary interactions often make forecasting of operationally important weather very difficult at KSC/CCAFS during the convective season (May-Oct). These convective processes often build quickly, last a short time (60 minutes or less), and occur over small distances, all of which also poses a significant challenge to the local forecasters who are responsible for issuing weather advisories, watches, and warnings. Surface winds during the transition seasons of spring and fall pose the most difficulties for the forecasters at WFF. They also encounter problems forecasting convective activity and temperature during those seasons. Therefore, accurate <span class="hlt">mesoscale</span> <span class="hlt">model</span> forecasts are needed to aid in their decision making. Both the ER and WFF would benefit greatly from high-resolution <span class="hlt">mesoscale</span> <span class="hlt">model</span> output to better forecast a variety of unique weather</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20100031067&hterms=momentum&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmomentum','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100031067&hterms=momentum&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmomentum"><span id="translatedtitle">Influence of Satellite-Based Heterogeneous Vegetation Momentum Roughness on <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Dynamics During IHOP 2002</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jasinski, Michael; Eastman, Joseph; Borak, Jordan</p> <p>2010-01-01</p> <p>The sensitivity of <span class="hlt">mesoscale</span> weather prediction <span class="hlt">model</span> to a vegetation roughness initialization is investigated for the south central United States. Three different roughness databases are employed: i) a control or standard lookup table roughness that is a function only of land cover type, ii) a spatially heterogeneous roughness database previously derived using a physically based procedure and MODIS imagery, and iii) a MODIS climatologic roughness database that possesses the same spatial heterogeneity as (i) but with mean land class values from (ii). The <span class="hlt">model</span> used is the Weather Research and Forecast <span class="hlt">Model</span> (WRF) coupled to the Community Land <span class="hlt">Model</span> within the Land Information System (LIS). For each simulation, a statistical comparison is made between <span class="hlt">modeled</span> results and ground observations from meteorological stations within the Oklahoma mesonet and surrounding region during IHOP20O2. A sensitivity analysis on the impact the MODIS-based roughness fields is also made through a time-series intercomparison of temperature bias, probability of detection (POD), average wind speed, boundary layer height, and turbulent kinetic energy (TKE) the results that, for the current replacement of the standard land-cover type based roughness values with the satellite-derived fields statistically improves <span class="hlt">model</span> performance for most of the observed variables. Further, the satellite-based roughness enhances the surface wind speed, PBL height and TKE production on the order of 3 to l0 percent, with a lesser effect over grassland and cropland domains, and the greater effect over mixed land cover domains</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004BAMS...85..709W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004BAMS...85..709W"><span id="translatedtitle">A Rapidly Deployable Operational <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> System for Emergency-Response Applications.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Warner, Thomas T.; Bowers, James F.; Swerdlin, Scott P.; Beitler, Brian A.</p> <p>2004-05-01</p> <p>An operational <span class="hlt">mesoscale</span> <span class="hlt">model</span> based forecasting system has been developed for use by U.S. Army Test and Evaluation Command meteorologists in their support of test-range operations. This paper reports on the adaptation of this system to permit its rapid deployment in support of a variety of civilian and military emergency-response applications. The innovation that allows for this rapid deployment is an intuitive graphical user interface that permits a non-expert to quickly configure the <span class="hlt">model</span> for a new application, and launch the forecast system to produce operational products without further intervention. The graphical interface is Web based and can be run on a wireless laptop or a personal digital assistant in the field. The instructions for configuring the <span class="hlt">modeling</span> system are transmitted to a compute engine [generally a personal computer (PC) cluster], and forecast products are placed on a Web site that can be accessed by emergency responders or other forecast users. This system has been used operationally for predicting the potential transport and dispersion of hazardous material during the 2002 Winter Olympics in Salt Lake City, Utah, and during military operations in Afghanistan. It has also been used operationally to satisfy the rapidly evolving needs of wildfire managers. Continued use of the <span class="hlt">modeling</span> system by nonexperts will allow developers to refine the graphical interface and make the <span class="hlt">model</span> and the interface more fault tolerant with respect to the decisions of <span class="hlt">model</span> users.(The National Center for Atmospheric Research is sponsored by the National Science Foundation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.H41F0959S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.H41F0959S"><span id="translatedtitle">Conditioning of a <span class="hlt">mesoscale</span> hydrologic <span class="hlt">model</span> with proxy soil moisture fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Samaniego-Eguiguren, L. E.; Bardossy, A.; Kumar, R.</p> <p>2009-12-01</p> <p>Multiscale monitoring and data assimilation techniques are fundamental to improve the predictability of <span class="hlt">mesoscale</span> distributed hydrologic <span class="hlt">models</span>. In-situ measurements along with remote sensed information can be used to condition the parametrization of distributed <span class="hlt">models</span> aiming at reducing their prediction uncertainty of both energy and mass balances. One of the key state variables responsible for the feedback mechanisms in the land-surface-atmosphere system is the soil moisture. This variable, on the contrary to other water fluxes, has a long memory and depends greatly on local conditions. The spatial distribution of soil moisture is therefore crucial to determine the spatial patterns of both surface runoff and actual evaporation. There are a number of proxies that can be used to describe the evolution of this state variable. They can be obtained at different resolutions, for example, the land surface temperature of the MODIS (NASA) sensor (1 x 1) km or the surface soil moisture (SSM) data based on ERS and METOP scatterometers (12.5 x 12.5) km. In this study we develop local-neighborhood estimators that help to constrain the spatio-temporal evolution of the top-layer soil moisture during a period of time. These estimators are included in the calibration process as a penalty function. The <span class="hlt">mesoscale</span> hydrologic <span class="hlt">model</span> (mHM) employed in this study is forced with (1 x 1) km daily meteorological variables such as precipitation, temperature and potential evapotranspiration. All parameters of mHM were regionalized with a multi-scale parametrization technique. The <span class="hlt">model</span> was set up in the Neckar Basin in south Germany for the period 2001 to 2007, from which the first four years were used for calibration. The spin up period of the <span class="hlt">model</span> was from 1992 to 2001. The search of good parameter sets was carried out with simulated annealing. Multiscale conditioning of soil moisture states in addition to the commonly used streamflow data lead to a significant reduction of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016CompM..58..635H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016CompM..58..635H"><span id="translatedtitle">An efficient FE-SBFE coupled method for <span class="hlt">mesoscale</span> cohesive fracture <span class="hlt">modelling</span> of concrete</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Y. J.; Yang, Z. J.; Liu, G. H.; Chen, X. W.</p> <p>2016-10-01</p> <p>This study develops a method coupling the finite element method (FEM) and the scaled boundary finite element method (SBFEM) for efficient <span class="hlt">meso-scale</span> fracture <span class="hlt">modelling</span> of concrete for the first time. In this method, the aggregates are <span class="hlt">modelled</span> by SBFE polygons with boundaries discretised only, while the mortar matrix is <span class="hlt">modelled</span> by conventional finite elements. The semi-analytical SBFEM is implemented in ABAQUS by a user-defined element subroutine for the first time. Nonlinear cohesive interface elements with normal and shear traction-separation constitutive laws are pre-inserted within the mortar and on the aggregate-mortar interfaces to simulate potential cracks. Various meso-structures generated from both random aggregates and X-ray computed tomography images are <span class="hlt">modelled</span>. The results demonstrate that the coupled method leads to considerable reductions in degrees of freedom and computational time against the conventional FEM, and these reductions become more significant when the aggregate volume fraction increases. The <span class="hlt">modelled</span> crack paths and load-carrying capacities of a three-point bending beam and an L-shaped panel are in excellent agreement with the experimental data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992PhDT........45Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992PhDT........45Y"><span id="translatedtitle">Impact of a Newtonian Assimilation and Physical Initialization on the Initialization and Prediction in a Tropical <span class="hlt">Mesoscale</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>Yap, Kok-Seng</p> <p></p> <p>One of the major limitations of tropical hydrostatic <span class="hlt">mesoscale</span> <span class="hlt">models</span> initialized through synoptic and subsynoptic scale data and operating on a grid resolution of 20-50km is that they show limited skill in simulating the spatial and temporal distribution of precipitation despite well -predicted synoptic and subsynoptic-scale flow patterns. In general the <span class="hlt">models</span> show a precipitation spin-up phase, however once activated, the <span class="hlt">model</span> tends to become convectively overactive through the synoptic scale-<span class="hlt">mesoscale</span> feedback mechanism. Our experience suggests that for the tropics where the <span class="hlt">mesoscale</span> circulations are convectively active, the precipitation spin-up arises from the inability of the initial synoptic-scale analysis to produce dynamic, thermodynamic and moisture fields capable of supporting convection on the <span class="hlt">mesoscale</span>. In particular, the problem lies in the wrong initial analysis of the velocity divergence and moisture fields. The overactive convection in the <span class="hlt">model</span> arises when the <span class="hlt">model</span> fails to initiate convection over some of the areas that are observed to precipitate, hence feeding the available moisture into the <span class="hlt">model</span> activated regions. It is shown in this study that this spin-up and overactive convection problem can be overcome by carrying out a dynamic Newtonian assimilation coupled with physical initialization during a preforecast integration phase of the <span class="hlt">model</span>. In particular it is shown that the Newtonian assimilation of the rotational component of the wind and surface pressure coupled with physical initialization of surface fluxes of moisture, cumulus parameterization and outgoing longwave radiation (OLR) enables the <span class="hlt">model</span> to build the divergence and moisture fields at the required location. The cumulus initialization is done through a humidity reanalysis via a "Reverse Kuo" algorithm. The surface latent heat flux initialization is done by reanalysis of the <span class="hlt">model</span>'s lowest level humidity fields through a "Reverse similarity algorithm", and the OLR</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120002859','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120002859"><span id="translatedtitle">An OSSE on <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Assimilation of Simulated HIRAD-Observed Hurricane Surface Winds</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Albers, Cerese; Miller, Timothy; Uhlhorn, Eric; Krishnamurti, T. N.</p> <p>2012-01-01</p> <p>The hazards of landfalling hurricanes are well known, but progress on improving the intensity forecasts of these deadly storms at landfall has been slow. Many cite a lack of high-resolution data sets taken inside the core of a hurricane, and the lack of reliable measurements in extreme conditions near the surface of hurricanes, as possible reasons why even the most state-of-the-art forecasting <span class="hlt">models</span> cannot seem to forecast intensity changes better. The Hurricane Imaging Radiometer (HIRAD) is a new airborne microwave remote sensor for observing hurricanes, and is operated and researched by NASA Marshall Space Flight Center in partnership with the NOAA Atlantic Oceanographic and Meteorological Laboratory/Hurricane Research Division, the University of Central Florida, the University of Michigan, and the University of Alabama in Huntsville. This instrument?s purpose is to study the wind field of a hurricane, specifically observing surface wind speeds and rain rates, in what has traditionally been the most difficult areas for other instruments to study; the high wind and heavy rain regions. Dr. T. N. Krishnamurti has studied various data assimilation techniques for hurricane and monsoon rain rates, and this study builds off of results obtained from utilizing his style of physical initializations of rainfall observations, but obtaining reliable observations in heavy rain regions has always presented trouble to our research of high-resolution rainfall forecasting. Reliable data from these regions at such a high resolution and wide swath as HIRAD provides is potentially very valuable to <span class="hlt">mesoscale</span> forecasting of hurricane intensity. This study shows how the data assimilation technique of Ensemble Kalman Filtering (EnKF) in the Weather Research and Forecasting (WRF) <span class="hlt">model</span> can be used to incorporate wind, and later rain rate, data into a <span class="hlt">mesoscale</span> <span class="hlt">model</span> forecast of hurricane intensity. The study makes use of an Observing System Simulation Experiment (OSSE) with a simulated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://dceg.cancer.gov/tools/analysis/nested-cohort','NCI'); return false;" href="https://dceg.cancer.gov/tools/analysis/nested-cohort"><span id="translatedtitle"><span class="hlt">Nested</span> Cohort</span></a></p> <p><a target="_blank" href="http://www.cancer.gov">Cancer.gov</a></p> <p></p> <p></p> <p><span class="hlt">Nested</span>Cohort is an R software package for fitting Kaplan-Meier and Cox <span class="hlt">Models</span> to estimate standardized survival and attributable risks for studies where covariates of interest are observed on only a sample of the cohort.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.T54A..05H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.T54A..05H"><span id="translatedtitle">Experimental observations and a <span class="hlt">mesoscale</span> constitutive <span class="hlt">model</span> of rocks undergoing stress-driven melt segregation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Holtzman, B. K.; King, D. S.; Kohlstedt, D. L.</p> <p>2011-12-01</p> <p>Coupling between deformation and melt transport have long been recognized in field observations and inferred to be important in the dynamics of crustal and lithosphere dynamics. We are studying these processes with closely knit experimental and theoretical approaches. Here, we present a synthesis of experimental observations of strain weakening associated with strain partitioning in networks of melt-rich shear zones. Variability in the mechanical data from torsion experiments reflect different degrees of melt segregation, due to different material properties, stress levels and boundary conditions (constant torque or constant twist rate). To explore this variability in more detail, we develop a <span class="hlt">mesoscale</span> constitutive <span class="hlt">model</span> that treats segregation as a process occurring within the representative elementary volume, described by internal state variables. This constitutive <span class="hlt">model</span> is comprised of several aspects, including 1) mass balance, 2) mechanical energy balance, and 3) an evolution equation for a single internal state variable describing the degree of melt segregation. At present, the evolution equation is relatively empirical, designed to allow us to quantify the sensitivity of the segregation rate to stress levels. These variations can be seen in the macroscopic creep data as well as the melt distribution within the torsion sample, which contains a continuous range of mechanical conditions from center to edge. The constitutive <span class="hlt">model</span> is formulated for easy implementation in numerical <span class="hlt">models</span>, in conjunction with common stress-, grain size- and temperature-dependent flow laws.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AtmEn..37.2451V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AtmEn..37.2451V"><span id="translatedtitle">A <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> study of wind blown dust on the Mexico City Basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Villasenor, Rafael; López-Villegas, M. T.; Eidels-Dubovoi, S.; Quintanar, Arturo; Gallardo, J. C.</p> <p></p> <p>The latest phase of the program to improve the air quality in the Valley of Mexico, also known, as Pro Aire is about to go into effect for the next 10 years. Pro Aire puts emphasis on agricultural wind erosion and associated dust emissions impacting downwind air quality. The main objective of this investigation was to use an empirical USEPA erosion <span class="hlt">model</span> coupled to a meteorological/transport-dispersion prediction <span class="hlt">model</span>, CALMET/CALPUFF, to estimate dust emissions and concentrations in the Mexico City Basin. The <span class="hlt">model</span> simulations for particulate matter (PM 10) are validated against observations taken at the most recent research field study, the IMADA-AVER field campaign, conducted during the spring of 1997 to provide information about high ozone, particulate matter concentrations and visibility impairment. The spatial and temporal PM distribution in the region is presented for a specific wind blown dust event consisting of two IMADA days, in order to understand how soil dust emissions from agricultural fallow land affect downwind areas during the dry season. Results show good agreement with the main spatial features of the local wind circulation and wind blown dust concentrations. A correlation coefficient of nearly 0.8 between predictions and observations for a <span class="hlt">modeled</span> day suggests that an important portion of the total measured concentration had geological origin. This work constitutes an essential advancement on the <span class="hlt">mesoscale</span> air quality problem on the MCMA due to wind erosion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A53G..05J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A53G..05J"><span id="translatedtitle">Air-sea Energy Transfer at <span class="hlt">Mesoscale</span> in a Coupled High-resolution <span class="hlt">Model</span>: Impact of Resolution and Current Feedback</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jullien, S.; Colas, F.; Masson, S. G.; Oerder, V.; Echevin, V.; Samson, G.; Crétat, J.; Berthet, S.; Hourdin, C.</p> <p>2015-12-01</p> <p>Winds are usually considered to force the ocean but recent studies suggested that oceanic <span class="hlt">mesoscale</span> activity, characterized by eddies, filaments and fronts, could also affect the wind field. These structures feature abrupt changes in sea surface temperature (SST), surface pressure and surface currents that could impact the atmosphere by enhancing/reducing air-sea fluxes, accelerating/decelerating winds, modifying the wind-pressure balance… At this time, the detailed processes associated to such coupling, its intensity and significance remain a matter of research. Here, a state-of-the-art WRF-OASIS-NEMO coupled <span class="hlt">model</span> is set up over a wide tropical channel (45°S-45°N) at various resolutions: 3/4°, 1/4° and 1/12° in both the ocean and the atmosphere. Several experiments are conducted in forced, partially or fully coupled modes, to highlight the effect of resolution and the role of SST vs. current feedback to energy injection into the ocean and the atmosphere. In strong <span class="hlt">mesoscale</span> activity regions, a negative wind power input from the atmosphere to the ocean is seen at scales ranging from 100km to more than 1000km. Nonexistent at 3/4°, this negative forcing, acting against oceanic <span class="hlt">mesoscale</span> activity, is almost twice more important at 1/12° than at 1/4°. In addition, partially coupled simulations, i.e. without current feedback, show that the impact of thermal coupling on this process is very limited. Energy injection to the marine atmospheric boundary layer also features imprints from oceanic <span class="hlt">mesoscale</span>. Energy injection by scales shorter than 300km represents up to 20% of the total. Finally we show that increasing oceanic resolution, and therefore <span class="hlt">mesoscale</span> activity, is necessary to resolve the full wind stress spectrum and has an upscaling effect by enhancing atmospheric <span class="hlt">mesoscale</span>, which is larger scale than in the ocean. Using 1/4°oceanic resolution instead of 1/12° leads to a 50% loss of energy in the atmospheric <span class="hlt">mesoscale</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=257881&keyword=go&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=78751966&CFTOKEN=80453209','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=257881&keyword=go&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=78751966&CFTOKEN=80453209"><span id="translatedtitle">Technical manual for basic version of the Markov chain <span class="hlt">nest</span> productivity <span class="hlt">model</span> (MCnest)</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 Markov Chain <span class="hlt">Nest</span> Productivity <span class="hlt">Model</span> (or MCnest) integrates existing toxicity information from three standardized avian toxicity tests with information on species life history and the timing of pesticide applications relative to the timing of avian breeding seasons to quantit...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=257882&keyword=bird&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=78733660&CFTOKEN=51069820','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=257882&keyword=bird&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=78733660&CFTOKEN=51069820"><span id="translatedtitle">User’s manual for basic version of MCnest Markov chain <span class="hlt">nest</span> productivity <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>The Markov Chain <span class="hlt">Nest</span> Productivity <span class="hlt">Model</span> (or MCnest) integrates existing toxicity information from three standardized avian toxicity tests with information on species life history and the timing of pesticide applications relative to the timing of avian breeding seasons to quantit...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27570365','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27570365"><span id="translatedtitle"><span class="hlt">Mesoscale</span> analysis of failure in quasi-brittle materials: comparison between lattice <span class="hlt">model</span> and acoustic emission data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grégoire, David; Verdon, Laura; Lefort, Vincent; Grassl, Peter; Saliba, Jacqueline; Regoin, Jean-Pierre; Loukili, Ahmed; Pijaudier-Cabot, Gilles</p> <p>2015-10-25</p> <p>The purpose of this paper is to analyse the development and the evolution of the fracture process zone during fracture and damage in quasi-brittle materials. A <span class="hlt">model</span> taking into account the material details at the <span class="hlt">mesoscale</span> is used to describe the failure process at the scale of the heterogeneities. This <span class="hlt">model</span> is used to compute histograms of the relative distances between damaged points. These numerical results are compared with experimental data, where the damage evolution is monitored using acoustic emissions. Histograms of the relative distances between damage events in the numerical calculations and acoustic events in the experiments exhibit good agreement. It is shown that the <span class="hlt">mesoscale</span> <span class="hlt">model</span> provides relevant information from the point of view of both global responses and the local failure process. © 2015 The Authors. International Journal for Numerical and Analytical Methods in Geomechanics published by John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950004194','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950004194"><span id="translatedtitle">Comparison and analysis of aircraft measurements and <span class="hlt">mesoscale</span> atmospheric chemistry <span class="hlt">model</span> simulations of tropospheric ozone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pleim, Jonathan E.; Ching, Jason K. S.</p> <p>1994-01-01</p> <p>The Regional Acid Deposition <span class="hlt">Model</span> (RADM) has been applied to several of the field experiments which were part of the Acid <span class="hlt">Models</span> Operational and Diagnostic Evaluation Study (Acid MODES). The experiment which was of particular interest with regards to ozone photochemistry involved horizontal zig-zag flight patterns (ZIPPER) over an area from the eastern Ohio River valley to the Adirondacks of New York. <span class="hlt">Model</span> simulations by both the standard resolution RADM (delta x = 80 km) and the <span class="hlt">nested</span> grid RADM (delta x = 26.7 km) compare well to measurements in the low emission regions in central Pennsylvania and upstate New York, but underestimate in the high emission upper Ohio River valley. The <span class="hlt">nested</span> simulation does considerably better, however, than the coarse grid simulation in terms of horizontal pattern and concentration magnitudes. Analysis of NO(x) and HO(x) concentrations and photochemical products rates of ozone show that the <span class="hlt">model</span>'s response to large point source emissions is very unsystematic both spatially and temporally. This is due to the <span class="hlt">models</span> instability to realistically simulate the small scale (subgrid) gradients in precursor concentrations in and around large point source plumes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.H13F1653G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.H13F1653G"><span id="translatedtitle">Simulation of CO2 dispersion in the atmospheric boundary layer using a <span class="hlt">mesoscale</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>Granvold, P. W.; Chow, F. K.; Oldenburg, C. M.</p> <p>2007-12-01</p> <p>The consequences of unexpected releases of CO2 from underground carbon sequestration sites must be understood before large-scale carbon capture and storage projects are implemented. Carbon dioxide gas can migrate through faults, fractures, or abandoned wells that penetrate the subsurface storage site and provide a pathway to the ground surface. Though such leakage is typically slow and in small amounts, CO2 can accumulate at the ground surface because it is denser than the surrounding atmosphere. Such accumulation presents health risks for humans and animals in the vicinity, and can cause damage to crops, trees, and other vegetation. Because atmospheric dispersion of CO2 is driven by gravity and ambient wind conditions, the danger from CO2 is greatest in regions with topographic depressions where the dense gas can pool, or under stably- stratified background atmospheric conditions which further inhibit mixing and dilution of the gas. We are developing a simulation tool for predictions of CO2 releases from underground storage sites in a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span>. The <span class="hlt">model</span> solves the compressible fluid flow equations, and has been modified to account for transport of dense gases. Example simulations from sources of different release strengths over various topography and background atmospheric conditions illustrate the behavior of the <span class="hlt">model</span> and its utility for risk assessment and certification of carbon sequestration sites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/840972','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/840972"><span id="translatedtitle">Multiphase <span class="hlt">Modeling</span> of Flow, Transport, and Biodegradation in a <span class="hlt">Mesoscale</span> Landfill Bioreactor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Oldenburg, Curtis M.; Borglin, Sharon E.; Hazen, Terry C.</p> <p>2002-02-01</p> <p>The need to control gas and leachate production and minimize refuse volume in municipal solid waste landfills has motivated the development of landfill simulation <span class="hlt">models</span> to predict and design optimal treatment processes. We have developed a multiphase and multicomponent nonisothermal module called T2LBM for the three-dimensional TOUGH2 flow and transport simulator. T2LBM can be used to simulate aerobic or anaerobic biodegradation of municipal solid waste and the associated flow and transport of gas and liquid through the refuse mass. Acetic acid is used as a proxy for all biodegradable substrates in the refuse. T2LBM incorporates a Monod kinetic rate law for the biodegradation of acetic acid by either aerobic or anaerobic microbes as controlled by the local oxygen concentration. We have verified the <span class="hlt">model</span> against published data, and applied it to our own <span class="hlt">mesoscale</span> laboratory aerobic landfill bioreactor experiments. We observe spatial variability of flow and biodegradation consistent with permeability heterogeneity and the geometry of the radial grid. The <span class="hlt">model</span> is capable of matching results of a shut-in test where the respiration of the system is measured over time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880001942&hterms=range+equation&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Drange%2Bequation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880001942&hterms=range+equation&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Drange%2Bequation"><span id="translatedtitle">Short range forecasting of sea breeze generated thunderstorms at the Kennedy Space Center: A real-time experiment using a primitive equation <span class="hlt">mesoscale</span> numerical <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>Lyons, Walter A.; Schuh, Jerome A.; Moon, Dennis; Pielke, Roger A.; Cotton, William; Arritt, Raymond</p> <p>1987-01-01</p> <p>The operational efficiency of using guidance from a <span class="hlt">mesoscale</span> numerical <span class="hlt">model</span> to improve sea breeze thunderstorm forecasts at and around the Shuttle landing strip was assessed. The Prognostic Three-Dimensional <span class="hlt">Mesoscale</span> (P3DM) <span class="hlt">model</span>, developed as a sea breeze <span class="hlt">model</span>, reveals a strong correlation between regions of <span class="hlt">mesoscale</span> convergence and the triggering of sea breeze convection thunderstorms. The P3DM was modified to generate stability parameters familiar to the operational forecaster. In addition to the <span class="hlt">mesoscale</span> fields of wind, vertical motion, moisture, temperature, a stability indicator, a combination of <span class="hlt">model</span>-predicted K and Lifted Indices and the maximum grid cell vertical motion, were proposed and tested. Results of blind tests indicate that a forecaster, provided with guidance derived from <span class="hlt">model</span> output, could improve local thunderstorm forecasts.</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/1993PhDT.......307S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993PhDT.......307S"><span id="translatedtitle">A Investigation of Colorado Front Range Winter Storms Using a Nonhydrostatic <span class="hlt">Mesoscale</span> Numerical <span class="hlt">Model</span> Designed for Operational Use</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Snook, John Stover</p> <p></p> <p>State-of-the-art data sources such as Doppler radar, automated surface observations, wind profiler, digital satellite, and aircraft reports are for the first time providing the capability to generate real-time, operational three-dimensional gridded data sets with sufficient spatial and temporal resolutions to diagnose the structure and evolution of <span class="hlt">mesoscale</span> systems. A prototype data assimilation system of this type, called the Local Analysis and Prediction System (LAPS), is being developed at the National Oceanic and Atmospheric System's Forecast Systems Laboratory (FSL). The investigation utilizes the three-dimensional LAPS analyses for initialization of the full physics, nonhydrostatic Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS) <span class="hlt">model</span> developed at the Colorado State University to create a system capable of generating operational <span class="hlt">mesoscale</span> predictions. The LAPS/RAMS system structured for operational use can add significant value to existing operational <span class="hlt">model</span> output and can provide an improved scientific understanding of <span class="hlt">mesoscale</span> weather events. The results are presented through two case study analyses, the 7 January 1992 Colorado Front Range blizzard and the 8-9 March 1992 eastern Colorado snow storm. Both cases are ideal for this investigation due to the significant <span class="hlt">mesoscale</span> variation observed in the precipitation and flow structure. The case study results demonstrate the ability to successfully detect and predict <span class="hlt">mesoscale</span> features using a <span class="hlt">mesoscale</span> numerical <span class="hlt">model</span> initialized with high resolution (10 km horizontal grid interval), non-homogeneous data. The strong influence of the Colorado topography on the resultant flow is suggested by the generation of a lee vortex that frequently develops east of the Front Range and south of the Cheyenne Ridge in stable, northwest synoptic flow. The lee vortex exhibits surface flow characteristics that are similar to results from low Froude number flow around an isolated obstacle. A series of numerical experiments using</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA621155','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA621155"><span id="translatedtitle">Conceptual <span class="hlt">Model</span> Development for Sea Turtle <span class="hlt">Nesting</span> Habitat: Support for USACE Navigation Projects</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2015-08-01</p> <p>value range schemes to include in a spatially explicit ecological <span class="hlt">model</span> for sea turtle <span class="hlt">nesting</span> habitat. INTRODUCTION: Much of the Atlantic and Gulf...create or improve the area. Key spatial parameters will be extracted from remote sensing data to be used as input in a spatially explicit ecological ...of key, spatial parameters and value range schemes to include in a spatially explicit ecological <span class="hlt">model</span> for sea turtle <span class="hlt">nesting</span> habitat. 15. SUBJECT</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22493306','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22493306"><span id="translatedtitle">An atomistically informed <span class="hlt">mesoscale</span> <span class="hlt">model</span> for growth and coarsening during discharge in lithium-oxygen batteries</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Welland, Michael J.; Lau, Kah Chun; Redfern, Paul C.; Wolf, Dieter; Curtiss, Larry A.; Liang, Linyun; Zhai, Denyun</p> <p>2015-12-14</p> <p>An atomistically informed <span class="hlt">mesoscale</span> <span class="hlt">model</span> is developed for the deposition of a discharge product in a Li-O{sub 2} battery. This mescocale <span class="hlt">model</span> includes particle growth and coarsening as well as a simplified nucleation <span class="hlt">model</span>. The <span class="hlt">model</span> involves LiO{sub 2} formation through reaction of O{sub 2}{sup −} and Li{sup +} in the electrolyte, which deposits on the cathode surface when the LiO{sub 2} concentration reaches supersaturation in the electrolyte. A reaction-diffusion (rate-equation) <span class="hlt">model</span> is used to describe the processes occurring in the electrolyte and a phase-field <span class="hlt">model</span> is used to capture microstructural evolution. This <span class="hlt">model</span> predicts that coarsening, in which large particles grow and small ones disappear, has a substantial effect on the size distribution of the LiO{sub 2} particles during the discharge process. The size evolution during discharge is the result of the interplay between this coarsening process and particle growth. The growth through continued deposition of LiO{sub 2} has the effect of causing large particles to grow ever faster while delaying the dissolution of small particles. The predicted size evolution is consistent with experimental results for a previously reported cathode material based on activated carbon during discharge and when it is at rest, although kinetic factors need to be included. The approach described in this paper synergistically combines <span class="hlt">models</span> on different length scales with experimental observations and should have applications in studying other related discharge processes, such as Li{sub 2}O{sub 2} deposition, in Li-O{sub 2} batteries and nucleation and growth in Li-S batteries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1287335','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1287335"><span id="translatedtitle">An atomistically informed <span class="hlt">mesoscale</span> <span class="hlt">model</span> for growth and coarsening during discharge in lithium-oxygen batteries</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Welland, Michael J.; Lau, Kah Chun; Redfern, Paul C.; Liang, Linyun; Zhai, Denyun; Wolf, Dieter; Curtiss, Larry A.</p> <p>2015-12-14</p> <p>An atomistically informed <span class="hlt">mesoscale</span> <span class="hlt">model</span> is developed for the deposition of a discharge product in a Li-O-2 battery. This mescocale <span class="hlt">model</span> includes particle growth and coarsening as well as a simplified nucleation <span class="hlt">model</span>. The <span class="hlt">model</span> involves LiO2 formation through reaction of O-2(-) and Li+ in the electrolyte, which deposits on the cathode surface when the LiO2 concentration reaches supersaturation in the electrolyte. A reaction-diffusion (rate-equation) <span class="hlt">model</span> is used to describe the processes occurring in the electrolyte and a phase-field <span class="hlt">model</span> is used to capture microstructural evolution. This <span class="hlt">model</span> predicts that coarsening, in which large particles grow and small ones disappear, has a substantial effect on the size distribution of the LiO2 particles during the discharge process. The size evolution during discharge is the result of the interplay between this coarsening process and particle growth. The growth through continued deposition of LiO2 has the effect of causing large particles to grow ever faster while delaying the dissolution of small particles. The predicted size evolution is consistent with experimental results for a previously reported cathode material based on activated carbon during discharge and when it is at rest, although kinetic factors need to be included. The approach described in this paper synergistically combines <span class="hlt">models</span> on different length scales with experimental observations and should have applications in studying other related discharge processes, such as Li2O2 deposition, in Li-O-2 batteries and nucleation and growth in Li-S batteries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5487152','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5487152"><span id="translatedtitle"><span class="hlt">Modeling</span> <span class="hlt">mesoscale</span> diffusion and transport processes for releases within coastal zones during land/sea breezes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lyons, W.A.; Keen, C.S.; Schuh, J.A.</p> <p>1983-12-01</p> <p>This document discusses the impacts of coastal <span class="hlt">mesoscale</span> regimes (CMRs) upon the transport and diffusion of potential accidental radionuclide releases from a shoreline nuclear power plant. CMRs exhibit significant spatial (horizontal and vertical) and temporal variability. Case studies illustrate land breezes, sea/lake breeze inflows and return flows, thermal internal boundary layers, fumigation, plume trapping, coastal convergence zones, thunderstorms and snow squalls. The direct application of a conventional Gaussian straight-line dose assessment <span class="hlt">model</span>, initialized only by on-site tower data, can potentially produce highly misleading guidance as to plume impact locations. Since much is known concerning CMRs, there are many potential improvements to modularized dose assessment codes, such as by proper parameterization of TIBLs, forecasting the inland penetration of convergence zones, etc. A three-dimensional primitive equation prognostic <span class="hlt">model</span> showed excellent agreement with detailed lake breeze field measurements, giving indications that such codes can be used in both diagnostic and prognostic studies. The use of relatively inexpensive supplemental meteorological data especially from remote sensing systems (Doppler sodar, radar, lightning strike tracking) and computerized data bases should save significantly on software development costs. Better quality assurance of emergency response codes could include systems of flags providing personnel with confidence levels as to the applicability of a code being used during any given CMR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990109664','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990109664"><span id="translatedtitle">Ocean Turbulence V: <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> in Level Coordinates. The Effect of Random Nature of Density</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Canuto, V. M.; Dubovikov, M. S.</p> <p>1998-01-01</p> <p>The main result of this paper is the derivation of a new expression for the tracer subgrid term in level coordinates S(l) to be employed in O-GCM. The novel feature is the proper account of the random nature of the density field which strongly affects the transformation from isopycnal to level coordinates of the variables of interest, velocity and tracer fields, their correlation functions and ultimately the subgrid terms. In deriving our result we made use of measured properties of vertical ocean turbulence. The major new results are: 1) the new subgrid expression is different from that of the heuristic GM <span class="hlt">model</span>, 2) u++(tracer)=1/2u+(thickness), where u++ and u+ are the tracer and thickness bolus velocities. In previous <span class="hlt">models</span>, u++ = u+, 2) the subgrid for a tracer tau is not the same as that for the density rho even when one accounts for the obvious absence of a diffusion term in the latter. The difference stems from a new treatment of the stochastic nature of the density, 3) the <span class="hlt">mesoscale</span> diffusivity enters both locally and non-locally, as the integral over all z's from the bottom of the ocean to the level z.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1257067','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1257067"><span id="translatedtitle">Evaluation of Test Methods for Triaxially Braided Composites using a <span class="hlt">Meso-Scale</span> Finite Element <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zhang, Chao</p> <p>2015-10-01</p> <p>The characterization of triaxially braided composite is complicate due to the nonuniformity of deformation within the unit cell as well as the possibility of the freeedge effect related to the large size of the unit cell. Extensive experimental investigation has been conducted to develop more accurate test approaches in characterizing the actual mechanical properties of the material we are studying. In this work, a <span class="hlt">meso-scale</span> finite element <span class="hlt">model</span> is utilized to simulate two complex specimens: notched tensile specimen and tube tensile specimen, which are designed to avoid the free-edge effect and free-edge effect induced premature edge damage. The full field strain data is predicted numerically and compared with experimental data obtained by Digit Image Correlation. The numerically predicted tensile strength values are compared with experimentally measured results. The discrepancy between numerically predicted and experimentally measured data, the capability of different test approaches are analyzed and discussed. The presented numerical <span class="hlt">model</span> could serve as assistance to the evaluation of different test methods, and is especially useful in identifying potential local damage events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003PApGe.160..429R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003PApGe.160..429R"><span id="translatedtitle">Three-dimensional Simulations of the Mean Air Transport During the 1997 Forest Fires in Kalimantan, Indonesia Using a <span class="hlt">Mesoscale</span> Numerical <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>Roswintiarti, O.; Raman, S.</p> <p></p> <p>- This paper describes the meteorological processes responsible for the mean transport of air pollutants during the ENSO-related forest fires in Kalimantan, Indonesia from 00 UTC 21 September to 00 UTC 25 September, 1997. The Fifth Generation of the Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> (MM5) is used to simulate three-dimensional winds at 6-hourly intervals. A nonhydrostatic version of the <span class="hlt">model</span> is run using two <span class="hlt">nested</span> grids with horizontal resolutions of 45 km and 15 km. From the simulated wind fields, the backward and forward trajectories of the air parcel are investigated using the Vis5D <span class="hlt">model</span>.The results indicate that the large-scale subsidence over Indonesia, the southwest monsoon low-level flows (2-8 m s-1), and the shallow planetary boundary layer height (400-800 m) play a key role in the transport of air pollutants from Kalimantan to Malaysia, Singapore and Brunei.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010HESSD...7.5299E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010HESSD...7.5299E"><span id="translatedtitle">Ensemble <span class="hlt">modelling</span> of nitrogen fluxes: data fusion for a Swedish <span class="hlt">meso-scale</span> catchment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Exbrayat, J.-F.; Viney, N. R.; Seibert, J.; Wrede, S.; Frede, H.-G.; Breuer, L.</p> <p>2010-08-01</p> <p><span class="hlt">Model</span> predictions of biogeochemical fluxes at the landscape scale are highly uncertain, both with respect to stochastic (parameter) and structural uncertainty. In this study 5 different <span class="hlt">models</span> (LASCAM, LASCAM-S, a self-developed tool, SWAT and HBV-N-D) designed to simulate hydrological fluxes as well as mobilisation and transport of one or several nitrogen species were applied to the <span class="hlt">mesoscale</span> River Fyris catchment in mid-eastern Sweden. Hydrological calibration against 5 years of recorded daily discharge at two stations gave highly variable results with Nash-Sutcliffe Efficiency (NSE) ranging between 0.48 and 0.83. Using the calibrated hydrological parameter sets, the parameter uncertainty linked to the nitrogen parameters was explored in order to cover the range of possible predictions of exported loads for 3 nitrogen species: nitrate (NO3), ammonium (NH4) and total nitrogen (Tot-N). For each <span class="hlt">model</span> and each nitrogen species, predictions were ranked in two different ways according to the performance indicated by two different goodness-of-fit measures: the coefficient of determination R2 and the root mean square error RMSE. A total of 2160 deterministic Single <span class="hlt">Model</span> Ensembles (SME) was generated using an increasing number of members (from the 2 best to the 10 best single predictions). Finally, the best SME for each <span class="hlt">model</span>, nitrogen species and discharge station were selected and merged into 330 different Multi-<span class="hlt">Model</span> Ensembles (MME). The evolution of changes in R2 and RMSE was used as a performance descriptor of the ensemble procedure. In each studied case, numerous ensemble merging schemes were identified which outperformed any of their members. Improvement rates were generally higher when worse members were introduced. The highest improvements were achieved for the nitrogen SMEs compiled with multiple linear regression <span class="hlt">models</span> with R2 selected members, which resulted in the RMSE decreasing by up to 90%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010HESS...14.2383E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010HESS...14.2383E"><span id="translatedtitle">Ensemble <span class="hlt">modelling</span> of nitrogen fluxes: data fusion for a Swedish <span class="hlt">meso-scale</span> catchment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Exbrayat, J.-F.; Viney, N. R.; Seibert, J.; Wrede, S.; Frede, H.-G.; Breuer, L.</p> <p>2010-12-01</p> <p><span class="hlt">Model</span> predictions of biogeochemical fluxes at the landscape scale are highly uncertain, both with respect to stochastic (parameter) and structural uncertainty. In this study 5 different <span class="hlt">models</span> (LASCAM, LASCAM-S, a self-developed tool, SWAT and HBV-N-D) designed to simulate hydrological fluxes as well as mobilisation and transport of one or several nitrogen species were applied to the <span class="hlt">mesoscale</span> River Fyris catchment in mid-eastern Sweden. Hydrological calibration against 5 years of recorded daily discharge at two stations gave highly variable results with Nash-Sutcliffe Efficiency (NSE) ranging between 0.48 and 0.83. Using the calibrated hydrological parameter sets, the parameter uncertainty linked to the nitrogen parameters was explored in order to cover the range of possible predictions of exported loads for 3 nitrogen species: nitrate (NO3), ammonium (NH4) and total nitrogen (Tot-N). For each <span class="hlt">model</span> and each nitrogen species, predictions were ranked in two different ways according to the performance indicated by two different goodness-of-fit measures: the coefficient of determination R2 and the root mean square error RMSE. A total of 2160 deterministic Single <span class="hlt">Model</span> Ensembles (SME) was generated using an increasing number of members (from the 2 best to the 10 best single predictions). Finally the best SME for each <span class="hlt">model</span>, nitrogen species and discharge station were selected and merged into 330 different Multi-<span class="hlt">Model</span> Ensembles (MME). The evolution of changes in R2 and RMSE was used as a performance descriptor of the ensemble procedure. In each studied case, numerous ensemble merging schemes were identified which outperformed any of their members. Improvement rates were generally higher when worse members were introduced. The highest improvements were achieved for the nitrogen SMEs compiled with multiple linear regression <span class="hlt">models</span> with R2 selected members, which resulted in the RMSE decreasing by up to 90%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/471412','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/471412"><span id="translatedtitle">The effect of urban canopy parameterizations on <span class="hlt">mesoscale</span> meteorological <span class="hlt">model</span> simulations in the Paso del Norte area</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brown, M.J.; Williams, M.D.</p> <p>1997-04-01</p> <p>Since <span class="hlt">mesoscale</span> numerical <span class="hlt">models</span> do not have the spatial resolution to directly simulate the fluid dynamics and thermodynamics in and around urban structures, urban canopy parameterizations are sometimes used to approximate the drag, heating, and enhanced turbulent kinetic energy (tke) produced by the sub-grid scale urban elements. In this paper, we investigate the effect of the urban canopy parameterizations used in the HOTMAC <span class="hlt">mesoscale</span> meteorological <span class="hlt">model</span> by turning the parameterizations on and off. The <span class="hlt">model</span> simulations were performed in the Paso del Norte region, which includes the cities of El Paso and Ciudad Juarez, the Franklin and Sierra Juarez mountains, and the Rio Grande. The metropolitan area is surrounded by relatively barren scrubland and is intersected by strips of vegetation along the Rio Grande. Results indicate that the urban canopy parameterizations do affect the <span class="hlt">mesoscale</span> flow field, reducing the magnitude of wind speed and changing the magnitude of the sensible heat flux and tke in the metropolitan area. A nighttime heat island and a daytime cool island exist when urban canopy parameters are turned on, but associated recirculation flows are not readily apparent. <span class="hlt">Model</span>-computed solar, net, and longwave radiation values look reasonable, agreeing for the most part with published measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcMod.106..104P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcMod.106..104P"><span id="translatedtitle">Optimizing dynamic downscaling in one-way <span class="hlt">nesting</span> using a regional 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>Pham, Van Sy; Hwang, Jin Hwan; Ku, Hyeyun</p> <p>2016-10-01</p> <p>Dynamical downscaling with <span class="hlt">nested</span> regional oceanographic <span class="hlt">models</span> has been demonstrated to be an effective approach for both operationally forecasted sea weather on regional scales and projections of future climate change and its impact on the ocean. However, when <span class="hlt">nesting</span> procedures are carried out in dynamic downscaling from a larger-scale <span class="hlt">model</span> or set of observations to a smaller scale, errors are unavoidable due to the differences in grid sizes and updating intervals. The present work assesses the impact of errors produced by <span class="hlt">nesting</span> procedures on the downscaled results from Ocean Regional Circulation <span class="hlt">Models</span> (ORCMs). Errors are identified and evaluated based on their sources and characteristics by employing the Big-Brother Experiment (BBE). The BBE uses the same <span class="hlt">model</span> to produce both <span class="hlt">nesting</span> and <span class="hlt">nested</span> simulations; so it addresses those error sources separately (i.e., without combining the contributions of errors from different sources). Here, we focus on discussing errors resulting from the spatial grids' differences, the updating times and the domain sizes. After the BBE was separately run for diverse cases, a Taylor diagram was used to analyze the results and recommend an optimal combination of grid size, updating period and domain sizes. Finally, suggested setups for the downscaling were evaluated by examining the spatial correlations of variables and the relative magnitudes of variances between the <span class="hlt">nested</span> <span class="hlt">model</span> and the original data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26712602','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26712602"><span id="translatedtitle">A <span class="hlt">meso-scale</span> layer-specific structural constitutive <span class="hlt">model</span> of the mitral heart valve leaflets.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Will; Ayoub, Salma; Liao, Jun; Sacks, Michael S</p> <p>2016-03-01</p> <p>Fundamental to developing a deeper understanding of pathophysiological remodeling in mitral valve (MV) disease is the development of an accurate tissue-level constitutive <span class="hlt">model</span>. In the present work, we developed a novel <span class="hlt">meso-scale</span> (i.e. at the level of the fiber, 10-100 μm in length scale) structural constitutive <span class="hlt">model</span> (MSSCM) for MV leaflet tissues. Due to its four-layer structure, we focused on the contributions from the distinct collagen and elastin fiber networks within each tissue layer. Requisite collagen and elastin fibrous structural information for each layer were quantified using second harmonic generation microscopy and conventional histology. A comprehensive mechanical dataset was also used to guide <span class="hlt">model</span> formulation and parameter estimation. Furthermore, novel to tissue-level structural constitutive <span class="hlt">modeling</span> approaches, we allowed the collagen fiber recruitment function to vary with orientation. Results indicated that the MSSCM predicted a surprisingly consistent mean effective collagen fiber modulus of 162.72 MPa, and demonstrated excellent predictive capability for extra-physiological loading regimes. There were also anterior-posterior leaflet-specific differences, such as tighter collagen and elastin fiber orientation distributions (ODF) in the anterior leaflet, and a thicker and stiffer atrialis in the posterior leaflet. While a degree of angular variance was observed, the tight valvular tissue ODF also left little room for any physically meaningful angular variance in fiber mechanical responses. Finally, a novel fibril-level (0.1-1 μm) validation approach was used to compare the predicted collagen fiber/fibril mechanical behavior with extant MV small angle X-ray scattering data. Results demonstrated excellent agreement, indicating that the MSSCM fully captures the tissue-level function. Future utilization of the MSSCM in computational <span class="hlt">models</span> of the MV will aid in producing highly accurate simulations in non-physiological loading states that can</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=234244&keyword=Winds&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=85819782&CFTOKEN=41643043','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=234244&keyword=Winds&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=85819782&CFTOKEN=41643043"><span id="translatedtitle">Examining Interior Grid Nudging Techniques Using Two-Way <span class="hlt">Nesting</span> in the WRF <span class="hlt">Model</span> for Regional Climate <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 study evaluates interior nudging techniques using the Weather Research and Forecasting (WRF) <span class="hlt">model</span> for regional climate <span class="hlt">modeling</span> over the conterminous United States (CONUS) using a two-way <span class="hlt">nested</span> configuration. NCEP–Department of Energy Atmospheric <span class="hlt">Model</span> Intercomparison Pro...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OcScD..12..493L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OcScD..12..493L"><span id="translatedtitle"><span class="hlt">Mesoscale</span> variability in the Arabian Sea from HYCOM <span class="hlt">model</span> results and observations: impact on the Persian Gulf Water path</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>L'Hégaret, P.; Duarte, R.; Carton, X.; Vic, C.; Ciani, D.; Baraille, R.; Corréard, S.</p> <p>2015-03-01</p> <p>The Arabian Sea and Sea of Oman circulation and water masses, subject to the monsoon forcing, reveal a strong seasonal variability and intense <span class="hlt">mesoscale</span> features. We describe and analyse this variability and these features, using both meteorological data (from ECMWF reanalyses), in-situ observations (from the ARGO float program and the GDEM climatology), satellite altimetry (from AVISO) and a regional simulation with a primitive equation <span class="hlt">model</span> (HYCOM). The EOFs of the seasonal variability of the water masses quantify their main changes in thermohaline characteristics and in position. The <span class="hlt">model</span> and observations display comparable variability, and the <span class="hlt">model</span> is then used to analyse the three-dimensional structure of eddies and water masses with a higher resolution. The <span class="hlt">mesoscale</span> eddies have a deep dynamical influence and strongly drive the water masses at depth. In particular, in the Sea of Oman, the Persian Gulf Water presents several offshore ejection sites and a complex recirculation, depending on the <span class="hlt">mesoscale</span> eddies. This water mass is also captured inside the eddies via several mechanisms, keeping high thermohaline characteristics in the Arabian Sea. These characteristics are validated on the GOGP99 cruise data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26602508','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26602508"><span id="translatedtitle">Electrostatic Interactions in Dissipative Particle Dynamics: Toward a <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> of the Polyelectrolyte Brushes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ibergay, Cyrille; Malfreyt, Patrice; Tildesley, Dominic J</p> <p>2009-12-08</p> <p>We report mesoscopic simulations of bulk electrolytes and polyelectrolyte brushes using the dissipative particle dynamics (DPD) method. The calculation of the electrostatic interactions is carried out using both the Ewald summation method and the particle-particle particle-mesh technique with charges distributed over the particles. The local components of the pressure tensor are calculated using the Irving and Kirkwood, and the method of planes and mechanical equilibrium is demonstrated. The profiles of the normal component of the pressure tensor are shown to be similar for both the Ewald and particle-particle particle-mesh methods for a single polyelectrolyte brush. We show that the PPPM method with the MOP technique is the appropriate choice for simulations of this type. The <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> of a strongly stretched polylectrolyte brush formed by strong charged polymer chains at a high grafting density shows that the polyelectrolyte follows the nonlinear osmotic regime, as expected from the calculation of the Gouy-Chapman length and the dimensionless Manning ratio.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140013352','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140013352"><span id="translatedtitle">Genesis of Hurricane Sandy (2012) Simulated with a Global <span class="hlt">Mesoscale</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>Shen, Bo-Wen; DeMaria, Mark; Li, J.-L. F.; Cheung, S.</p> <p>2013-01-01</p> <p>In this study, we investigate the formation predictability of Hurricane Sandy (2012) with a global <span class="hlt">mesoscale</span> <span class="hlt">model</span>. We first present five track and intensity forecasts of Sandy initialized at 00Z 22-26 October 2012, realistically producing its movement with a northwestward turn prior to its landfall. We then show that three experiments initialized at 00Z 16-18 October captured the genesis of Sandy with a lead time of up to 6 days and simulated reasonable evolution of Sandy's track and intensity in the next 2 day period of 18Z 21-23 October. Results suggest that the extended lead time of formation prediction is achieved by realistic simulations of multiscale processes, including (1) the interaction between an easterly wave and a low-level westerly wind belt (WWB) and (2) the appearance of the upper-level trough at 200 hPa to Sandy's northwest. The low-level WWB and upper-level trough are likely associated with a Madden-Julian Oscillation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20030054358&hterms=meteorology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmeteorology','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20030054358&hterms=meteorology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmeteorology"><span id="translatedtitle">Meteorology, Macrophysics, Microphysics, Microwaves, and <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> of Mediterranean Mountain Storms: The M8 Laboratory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Starr, David O. (Technical Monitor); Smith, Eric A.</p> <p>2002-01-01</p> <p>Comprehensive understanding of the microphysical nature of Mediterranean storms can be accomplished by a combination of in situ meteorological data analysis and radar-passive microwave data analysis, effectively integrated with numerical <span class="hlt">modeling</span> studies at various scales, from synoptic scale down through the <span class="hlt">mesoscale</span>, the cloud macrophysical scale, and ultimately the cloud microphysical scale. The microphysical properties of and their controls on severe storms are intrinsically related to meteorological processes under which storms have evolved, processes which eventually select and control the dominant microphysical properties themselves. This involves intense convective development, stratiform decay, orographic lifting, and sloped frontal lifting processes, as well as the associated vertical motions and thermodynamical instabilities governing physical processes that affect details of the size distributions and fall rates of the various types of hydrometeors found within the storm environment. Insofar as hazardous Mediterranean storms, highlighted in this study by three mountain storms producing damaging floods in northern Italy between 1992 and 2000, developing a comprehensive microphysical interpretation requires an understanding of the multiple phases of storm evolution and the heterogeneous nature of precipitation fields within a storm domain. This involves convective development, stratiform transition and decay, orographic lifting, and sloped frontal lifting processes. This also involves vertical motions and thermodynamical instabilities governing physical processes that determine details of the liquid/ice water contents, size disi:ributions, and fall rates of the various modes of hydrometeors found within hazardous storm environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.9022Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.9022Z"><span id="translatedtitle">A new raytracing algorithm to compute slant total delays in a <span class="hlt">mesoscale</span> atmospheric <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>Zus, Florian; Bender, Michael; Dick, Galina; Deng, Zhiguo; Heise, Stefan; Wickert, Jens</p> <p>2010-05-01</p> <p>Ray-tracing is essential to accurately simulate Global Positioning System (GPS) Slant Total Delays (STD) in a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span>. A rigorous ray-tracing algorithm based on Fermat's principle was developed to simulate the propagation of radio signals in a gridded 3D refractivity field. The unique in the proposed algorithm is that the solution automatically involves the exact location of the receiver and the satellite, i.e. 'shooting' is not required. The structured non-linear system of equations, arising due to the applied finite difference scheme, is solved by Newton's iteration. For elevation angles as low as 5 degree at a ground-based receiver a single Newton iteration turns out to be sufficient. Subsequently the algorithm allows us to simulate about 1500 STDs per second on a single CPU. Having developed the forward operator for STDs, we constructed the tangent linear and adjoint code for sensitivity and variational data analysis. First results from three potential applications of the proposed ray-tracing algorithm are presented: (1) monitoring STD data processed at the GFZ Potsdam against European Centre for Medium-Range Weather Forecasts (ECMWF) analysis, (2) vertical profiling, i.e. the retrieval of the refractivity profile above a ground based receiver from the STD data by using a least square adjustment, and (3) direct mapping.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20010021327&hterms=Data+Base+Technique&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DData%2BBase%2BTechnique','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20010021327&hterms=Data+Base+Technique&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DData%2BBase%2BTechnique"><span id="translatedtitle">Use of Geostationary Satellite Data to Force Land Surface Schemes within Atmospheric <span class="hlt">Mesoscale</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>Lapenta, William M.; Suggs, Ron; McNider, Richard T.; Jedlovec, Gary; Dembek, Scott R.; Goodman, H. Michael (Technical Monitor)</p> <p>2000-01-01</p> <p>A technique has been developed for assimilating GOES-derived skin temperature tendencies and insolation into the surface energy budget equation of a <span class="hlt">mesoscale</span> <span class="hlt">model</span> so that the simulated rate of temperature change closely agrees with the satellite observations. A critical assumption of the technique is that the availability of moisture (either from the soil or vegetation) is the least known term in the <span class="hlt">model</span>'s surface energy budget. Therefore, the simulated latent heat flux, which is a function of surface moisture availability, is adjusted based upon differences between the <span class="hlt">modeled</span> and satellite-observed skin temperature tendencies. An advantage of this technique is that satellite temperature tendencies are assimilated in an energetically consistent manner that avoids energy imbalances and surface stability problems that arise from direct assimilation of surface shelter temperatures. The fact that the rate of change of the satellite skin temperature is used rather than the absolute temperature means that sensor calibration is not as critical. The technique has been employed on a semi-operational basis at the GHCC within the PSU/NCAR MM5. Assimilation has been performed on a grid centered over the Southeastern US since November 1998. Results from the past year show that assimilation of the satellite data reduces both the bias and RMSE for simulations of surface air temperature and relative humidity. These findings are based on comparison of assimilation runs with a control using the simple 5-layer soil <span class="hlt">model</span> available in MM5. A significant development in the past several months was the inclusion of the detailed Oregon State University land surface <span class="hlt">model</span> (OSU/LSM) as an option within MM5. One of our working hypotheses has been that the assimilation technique, although simple, may provide better short-term forecasts than a detailed LSM that requires significant number initialized parameters. Preliminary results indicate that the assimilation out performs the OSU</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('http://adsabs.harvard.edu/abs/2011Geomo.130..230D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011Geomo.130..230D"><span id="translatedtitle"><span class="hlt">Meso-scale</span> <span class="hlt">modelling</span> of aeolian sediment input to coastal dunes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delgado-Fernandez, Irene</p> <p>2011-07-01</p> <p>The collection of a time series coupling hourly wind data (speed and direction) with sand transport over months has provided new insights into the dynamics of transport events that input sediment to the foredune at Greenwich Dunes, Prince Edward Island National Park, Canada. This paper summarises the key aspects of aeolian sediment movement for a period of 9 months and presents a <span class="hlt">modelling</span> approach for resolving aeolian transport to coastal dunes at the <span class="hlt">meso-scale</span>. The main hypothesis of the <span class="hlt">modelling</span> approach is that a small number of key factors control both the occurrence and the magnitude of transport events. Thresholds associated with these factors may be used to filter the time series and isolate potential transport periods over the year. The impacts of nearshore processes are included in the approach as part of the dynamics of coastal dunes, as are supply-limiting factors and trade-offs between fetch distances, angle of wind approach, and beach dimensions. A simple analytical procedure, based on previously published equations, is carried out to assess the general viability of the conceptual approach. Results show that the incorporation of moisture and fetch effects in the calculation of transport for isolated potential transport periods result in improved predictions of sediment input to the dune. Net changes, measured with three different techniques, suggest that survey data with coarse temporal resolution underestimates the amount of sand input to the dune, because sediment is often removed from the embryo dune and foredune by other processes such as wave scarping. Predictions obtained by the proposed <span class="hlt">modelling</span> approach are of the same order of magnitude as measured deposition and much less than predicted by <span class="hlt">models</span> based solely on wind speed and direction. Areas for improvement and alternative <span class="hlt">modelling</span> approaches, such as probabilistic approaches similar to weather forecasting, are covered in the discussion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.fort.usgs.gov/Products/Publications/pub_abstract.asp?PubID=3848','USGSPUBS'); return false;" href="http://www.fort.usgs.gov/Products/Publications/pub_abstract.asp?PubID=3848"><span id="translatedtitle"><span class="hlt">Modeling</span> and estimation of stage-specific daily survival probabilities of <span class="hlt">nests</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stanley, T.R.</p> <p>2000-01-01</p> <p>In studies of avian <span class="hlt">nesting</span> success, it is often of interest to estimate stage-specific daily survival probabilities of <span class="hlt">nests</span>. When data can be partitioned by <span class="hlt">nesting</span> stage (e.g., incubation stage, nestling stage), piecewise application of the Mayfield method or Johnsona??s method is appropriate. However, when the data contain <span class="hlt">nests</span> where the transition from one stage to the next occurred during the interval between visits, piecewise approaches are inappropriate. In this paper, I present a <span class="hlt">model</span> that allows joint estimation of stage-specific daily survival probabilities even when the time of transition between stages is unknown. The <span class="hlt">model</span> allows interval lengths between visits to <span class="hlt">nests</span> to vary, and the exact time of failure of <span class="hlt">nests</span> does not need to be known. The performance of the <span class="hlt">model</span> at various sample sizes and interval lengths between visits was investigated using Monte Carlo simulations, and it was found that the <span class="hlt">model</span> performed quite well: bias was small and confidence-interval coverage was at the nominal 95% rate. A SAS program for obtaining maximum likelihood estimates of parameters, and their standard errors, is provided in the Appendix.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040016359&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSeasons','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040016359&hterms=Seasons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSeasons"><span id="translatedtitle">Diabatic Initialization of <span class="hlt">Mesoscale</span> <span class="hlt">Models</span> in the Southeastern United States: Can 0 to 12h Warm Season QPF be Improved?</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lapenta, William M.; Bradshaw, Tom; Burks, Jason; Darden, Chris; Dembek, Scott</p> <p>2003-01-01</p> <p>It is well known that numerical warm season quantitative precipitation forecasts lack significant skill for numerous reasons. Some are related to the <span class="hlt">model</span>--it may lack physical processes required to realistically simulate convection or the numerical algorithms and dynamics employed may not be adequate. Others are related to initialization-<span class="hlt">mesoscale</span> features play an important role in convective initialization and atmospheric observation systems are incapable of properly depicting the three-dimensional stability structure at the <span class="hlt">mesoscale</span>. The purpose of this study is to determine if a <span class="hlt">mesoscale</span> <span class="hlt">model</span> initialized with a diabatic initialization scheme can improve short-term (0 to 12h) warm season quantitative precipitation forecasts in the Southeastern United States. The Local Analysis and Prediction System (LAPS) developed at the Forecast System Laboratory is used to diabatically initialize the Pennsylvania State University/National center for Atmospheric Research (PSUNCAR) <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> version 5 (MM5). The SPORT Center runs LAPS operationally on an hourly cycle to produce analyses on a 15 km covering the eastern 2/3 of the United States. The 20 km National Centers for Environmental Prediction (NCEP) Rapid Update Cycle analyses are used for the background fields. Standard observational data are acquired from MADIS with GOES/CRAFT Nexrad data acquired from in-house feeds. The MM5 is configured on a 140 x 140 12 km grid centered on Huntsville Alabama. Preliminary results indicate that MM5 runs initialized with LAPS produce improved 6 and 12h QPF threat scores compared with those initialized with the NCEP RUC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT........29Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT........29Y"><span id="translatedtitle">Investigation into a displacement bias in numerical weather prediction <span class="hlt">models</span>' forecasts of <span class="hlt">mesoscale</span> convective systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yost, Charles</p> <p></p> <p>Although often hard to correctly forecast, <span class="hlt">mesoscale</span> convective systems (MCSs) are responsible for a majority of warm-season, localized extreme rain events. This study investigates displacement errors often observed by forecasters and researchers in the Global Forecast System (GFS) and the North American <span class="hlt">Mesoscale</span> (NAM) <span class="hlt">models</span>, in addition to the European Centre for Medium Range Weather Forecasts (ECMWF) and the 4-km convection allowing NSSL-WRF <span class="hlt">models</span>. Using archived radar data and Stage IV precipitation data from April to August of 2009 to 2011, MCSs were recorded and sorted into unique six-hour intervals. The locations of these MCSs were compared to the associated predicted precipitation field in all <span class="hlt">models</span> using the Method for Object-Based Diagnostic Evaluation (MODE) tool, produced by the Developmental Testbed Center and verified through manual analysis. A northward bias exists in the location of the forecasts in all lead times of the GFS, NAM, and ECMWF <span class="hlt">models</span>. The MODE tool found that 74%, 68%, and 65% of the forecasts were too far to the north of the observed rainfall in the GFS, NAM and ECMWF <span class="hlt">models</span> respectively. The higher-resolution NSSL-WRF <span class="hlt">model</span> produced a near neutral location forecast error with 52% of the cases too far to the south. The GFS <span class="hlt">model</span> consistently moved the MCSs too quickly with 65% of the cases located to the east of the observed MCS. The mean forecast displacement error from the GFS and NAM were on average 266 km and 249 km, respectively, while the ECMWF and NSSL-WRF produced a much lower average of 179 km and 158 km. A case study of the Dubuque, IA MCS on 28 July 2011 was analyzed to identify the root cause of this bias. This MCS shattered several rainfall records and required over 50 people to be rescued from mobile home parks from around the area. This devastating MCS, which was a classic Training Line/Adjoining Stratiform archetype, had numerous northward-biased forecasts from all <span class="hlt">models</span>, which are examined here. As common with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.5855H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.5855H"><span id="translatedtitle">Validation of the <span class="hlt">mesoscale</span> <span class="hlt">model</span> MM5 in reproducing the wind variability in Turkey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hidalgo, A.; Marchante, M.; Jiménez, P. A.; García-Bustamante, E.; Montávez, J. P.; Gómez-Navarro, J. J.; Rico, M. C.; Jerez, S.; Navarro, J.; González-Rouco, J. F.</p> <p>2009-04-01</p> <p>The numerous studies assessing the evolution of climate and its potential change at the global scale evidence the need of estimating the impact of expected changes at the regional scale. Particularly interesting is the evaluation of the wind energy resource due to its involvement in the the development and sustainability assessment of alternative energies supply. Prior to a climate change impact evaluation the knowledge of the wind field spatial and temporal variability is required. Various techniques can be applied in order to analyze the surface circulations, their main synoptic forcings and their variability along the recent past climate. A dynamical downscaling approach is applied for an evaluation of the wind resource over Turkey. The study leans on the high resolution simulation of the wind field over Turkey and its validation with an observational dataset. The high resolution climate simulation has been performed with the <span class="hlt">mesoscale</span> <span class="hlt">model</span> MM5, driven by the global <span class="hlt">model</span> ERA40 reanalysis products, for a period of ten years at 10 km of horizontal resolution. In order to analyze the reliability of the simulations, an observational dataset of quality that spans the period from 1978 to 2008 and overlaps the simulation period has been prepared. Observations reveal the presence of a strong annual cycle for the wind field in the region, with maxima wind speeds and prevailing northern circulations appearing in Summer and minima wind speed and a larger variability of the wind direction in Winter. The evaluation of the <span class="hlt">model</span> results, based on the assessement of the distribution concordance and temporal agreement between simulations and surface observations, revealed that the <span class="hlt">model</span> reproduces the regional variability with a systematic wind speed overestimation and evidences accuracy in reproducing the monthly mean wind field and its variability, showing a certain degradation at daily timescales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/945797','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/945797"><span id="translatedtitle"><span class="hlt">Meso-Scale</span> <span class="hlt">Modeling</span> of Spall in a Heterogeneous Two-Phase Material</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Springer, Harry Keo</p> <p>2008-07-11</p> <p>The influence of the heterogeneous second-phase particle structure and applied loading conditions on the ductile spall response of a <span class="hlt">model</span> two-phase material was investigated. Quantitative metallography, three-dimensional (3D) <span class="hlt">meso-scale</span> simulations (MSS), and small-scale spall experiments provided the foundation for this study. Nodular ductile iron (NDI) was selected as the <span class="hlt">model</span> two-phase material for this study because it contains a large and readily identifiable second- phase particle population. Second-phase particles serve as the primary void nucleation sites in NDI and are, therefore, central to its ductile spall response. A mathematical <span class="hlt">model</span> was developed for the NDI second-phase volume fraction that accounted for the non-uniform particle size and spacing distributions within the framework of a length-scale dependent Gaussian probability distribution function (PDF). This <span class="hlt">model</span> was based on novel multiscale sampling measurements. A methodology was also developed for the computer generation of representative particle structures based on their mathematical description, enabling 3D MSS. MSS were used to investigate the effects of second-phase particle volume fraction and particle size, loading conditions, and physical domain size of simulation on the ductile spall response of a <span class="hlt">model</span> two-phase material. MSS results reinforce existing <span class="hlt">model</span> predictions, where the spall strength metric (SSM) logarithmically decreases with increasing particle volume fraction. While SSM predictions are nearly independent of applied load conditions at lower loading rates, which is consistent with previous studies, loading dependencies are observed at higher loading rates. There is also a logarithmic decrease in SSM for increasing (initial) void size, as well. A <span class="hlt">model</span> was developed to account for the effects of loading rate, particle size, matrix sound-speed, and, in the NDI-specific case, the probabilistic particle volume fraction <span class="hlt">model</span>. Small-scale spall experiments were designed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMIN11D1480W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMIN11D1480W"><span id="translatedtitle">An Automated Method to Identify <span class="hlt">Mesoscale</span> Convective Complexes in the Regional Climate <span class="hlt">Model</span> Evaluation System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whitehall, K. D.; Jenkins, G. S.; Mattmann, C. A.; Waliser, D. E.; Kim, J.; Goodale, C. E.; Hart, A. F.; Ramirez, P.; Whittell, J.; Zimdars, P. A.</p> <p>2012-12-01</p> <p><span class="hlt">Mesoscale</span> convective complexes (MCCs) are large (2 - 3 x 105 km2) nocturnal convectively-driven weather systems that are generally associated with high precipitation events in short durations (less than 12hrs) in various locations through out the tropics and midlatitudes (Maddox 1980). These systems are particularly important for climate in the West Sahel region, where the precipitation associated with them is a principal component of the rainfall season (Laing and Fritsch 1993). These systems occur on weather timescales and are historically identified from weather data analysis via manual and more recently automated processes (Miller and Fritsch 1991, Nesbett 2006, Balmey and Reason 2012). The Regional Climate <span class="hlt">Model</span> Evaluation System (RCMES) is an open source tool designed for easy evaluation of climate and Earth system data through access to standardized datasets, and intrinsic tools that perform common analysis and visualization tasks (Hart et al. 2011). The RCMES toolkit also provides the flexibility of user-defined subroutines for further metrics, visualization and even dataset manipulation. The purpose of this study is to present a methodology for identifying MCCs in observation datasets using the RCMES framework. TRMM 3 hourly datasets will be used to demonstrate the methodology for 2005 boreal summer. This method promotes the use of open source software for scientific data systems to address a concern to multiple stakeholders in the earth sciences. A historical MCC dataset provides a platform with regards to further studies of the variability of frequency on various timescales of MCCs that is important for many including climate scientists, meteorologists, water resource managers, and agriculturalists. The methodology of using RCMES for searching and clipping datasets will engender a new realm of studies as users of the system will no longer be restricted to solely using the datasets as they reside in their own local systems; instead will be afforded rapid</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcSci..12.1249L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcSci..12.1249L"><span id="translatedtitle">GEM: a dynamic tracking <span class="hlt">model</span> for <span class="hlt">mesoscale</span> eddies in the ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Qiu-Yang; Sun, Liang; Lin, Sheng-Fu</p> <p>2016-12-01</p> <p>The Genealogical Evolution <span class="hlt">Model</span> (GEM) presented here is an efficient logical <span class="hlt">model</span> used to track dynamic evolution of <span class="hlt">mesoscale</span> eddies in the ocean. It can distinguish between different dynamic processes (e.g., merging and splitting) within a dynamic evolution pattern, which is difficult to accomplish using other tracking methods. To this end, the GEM first uses a two-dimensional (2-D) similarity vector (i.e., a pair of ratios of overlap area between two eddies to the area of each eddy) rather than a scalar to measure the similarity between eddies, which effectively solves the "missing eddy" problem (temporarily lost eddy in tracking). Second, for tracking when an eddy splits, the GEM uses both "parent" (the original eddy) and "child" (eddy split from parent) and the dynamic processes are described as the birth and death of different generations. Additionally, a new look-ahead approach with selection rules effectively simplifies computation and recording. All of the computational steps are linear and do not include iteration. Given the pixel number of the target region L, the maximum number of eddies M, the number N of look-ahead time steps, and the total number of time steps T, the total computer time is O(LM(N + 1)T). The tracking of each eddy is very smooth because we require that the snapshots of each eddy on adjacent days overlap one another. Although eddy splitting or merging is ubiquitous in the ocean, they have different geographic distributions in the North Pacific Ocean. Both the merging and splitting rates of the eddies are high, especially at the western boundary, in currents and in "eddy deserts". The GEM is useful not only for satellite-based observational data, but also for numerical simulation outputs. It is potentially useful for studying dynamic processes in other related fields, e.g., the dynamics of cyclones in meteorology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AtmEn..40.7983A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AtmEn..40.7983A"><span id="translatedtitle">Impact of two chemistry mechanisms fully coupled with <span class="hlt">mesoscale</span> <span class="hlt">model</span> on the atmospheric pollutants distribution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arteta, J.; Cautenet, S.; Taghavi, M.; Audiffren, N.</p> <p></p> <p> time on SGI 3800 with 30 processors). Simplified mechanisms are really important to study cases for which an online coupling is necessary between <span class="hlt">meso-scale</span> and chemistry <span class="hlt">models</span> (clouds or aerosols plumes impacts, highly variable meteorology).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=coefficient&pg=5&id=EJ1004545','ERIC'); return false;" href="http://eric.ed.gov/?q=coefficient&pg=5&id=EJ1004545"><span id="translatedtitle">Comparing Regression Coefficients between <span class="hlt">Nested</span> Linear <span class="hlt">Models</span> for Clustered Data with Generalized Estimating Equations</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>Yan, Jun; Aseltine, Robert H., Jr.; Harel, Ofer</p> <p>2013-01-01</p> <p>Comparing regression coefficients between <span class="hlt">models</span> when one <span class="hlt">model</span> is <span class="hlt">nested</span> within another is of great practical interest when two explanations of a given phenomenon are specified as linear <span class="hlt">models</span>. The statistical problem is whether the coefficients associated with a given set of covariates change significantly when other covariates are added into…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA522837','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA522837"><span id="translatedtitle">A Coupled <span class="hlt">Mesoscale-Model</span> Fourier-Method for Idealized Mountain-Wave Simulations Over Hawaii</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2010-01-01</p> <p>overview of mountain waves observed over the Pyrenees during the <span class="hlt">Mesoscale</span> Alpine Project, “...any quantitative prediction of mountain wave...above the downslope of Mauna Loa and Mauna Kea were governed by nonlinear responses not captured by hds, and that two additional and larger flux peaks</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA522262','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA522262"><span id="translatedtitle">A Coupled <span class="hlt">Mesoscale-Model</span> Fourier Method for Mountain Waves Over Hawaii</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2010-01-01</p> <p>2008a; Eckermann et al, 2009). As Smith et al (2007) note 3 in their overview of mountain waves observed over the Pyrenees during the <span class="hlt">Mesoscale</span> Alpine...smaller than the FT/WRF wave drag values. Given that the two wave-flux peaks above the downslope of Mauna Loa and Mauna Kea were governed by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA....11501B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA....11501B"><span id="translatedtitle">Steps towards regional climate <span class="hlt">modelling</span> in tropical Westafrica using a nonhydrostatic <span class="hlt">mesoscale</span> <span class="hlt">model</span>: studies on AEW dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Born, K.; Bachner, S.; Brienen, C.</p> <p>2003-04-01</p> <p>During summer 2002, an intense observational campaign in Benin allowed identification and classification of rainfall events in the Upper Oueme valley. Hindcasts with the "Lokalmodell" (LM) of the German Weather Service showed some deficiencies in the short to medium range forecasts of observed events. In most cases, insufficient initial states especially of moisture fields could be identified as causes of failures. But also in the dynamics of the AEW, which are obviously essential for the generation of <span class="hlt">mesoscale</span> convective systems, problems seemed to arise. Concept studies with idealized initial conditions have been undertaken in order to simulate AEW dynamics and according precipitation on time scales of 1-3 months. The initial fields were changed stepwise to more realistic conditions, showing the effect of orography, SST and soil moisture on rainfall prediction on monthly timescales. Although the <span class="hlt">model</span> results in general are acceptable, still some differences to observations in location and strength of the AEJ exist.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AtmRe..95..428S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AtmRe..95..428S"><span id="translatedtitle">Analysis of an extremely dense regional fog event in Eastern China using a <span class="hlt">mesoscale</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>Shi, Chune; Yang, Jun; Qiu, Mingyan; Zhang, Hao; Zhang, Su; Li, Zihua</p> <p>2010-03-01</p> <p>An unusually dense regional advection-radiation fog event over Anhui and the surrounding provinces in eastern China during Dec. 25-27, 2006, was investigated. At its mature stage, the fog covered most Anhui and parts of the surrounding provinces, reducing visibility to 100 m or less. It lasted more than 36 consecutive hours in some places. A <span class="hlt">mesoscale</span> meteorological <span class="hlt">model</span> (MM5), together with back-trajectory analysis, was used to investigate this fog event. The observations from a field station as well as hundreds of routine stations, along with two sets of visibility computing methods, were used to quantitatively and objectively validate the MM5 simulated liquid water content (LWC) and visibility. The verifications demonstrate that MM5 has a better fog predictability for the first day compared to the second day forecast, and better fog predictability compared to dense fog predictability with regard to the probability of detection (POD) and the threat score (TS). The new visibility algorithm that uses both LWC and number density of fog droplets significantly outperforms the conventional LWC-only based one in the fog prediction in terms of the POD score, especially for dense fog prediction. The objective verification in this work is the first time conducted for MM5 fog prediction, with which we can better understand the performance of simulated temporal and spatial fog coverage. The back-trajectory and sensitivity experiments confirm that subsidence and the steady warm and moist advections from southeast and southwest maintained the dense fog while the northwesterly dry wind resulted in dissipation of the fog.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.5524B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.5524B"><span id="translatedtitle">A new Approach to Estimate Initial Condition Uncertainty Structures in <span class="hlt">Mesoscale</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>Bach, Liselotte; Keller, Jan D.; Hense, Andreas</p> <p>2013-04-01</p> <p> assess the corresponding uncertainty structures. Through the use of diverse norms for the measurement of the perturbation growth and different rescaling interval lengths, the technique also allows for the estimation of uncertainty patterns related to specific phenomena like convection, turbulence or fronts. Both a stationary and a progressive self breeding are implemented in a limitred-area, <span class="hlt">mesoscale</span> NWP <span class="hlt">model</span>. In several case studies (e.g., fronts, inversions, air mass convection) we present applications of the self-breeding technique to identify uncertainty structures on different temporal and spatial scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JGRE..110.6005F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JGRE..110.6005F"><span id="translatedtitle">Aeolian processes in Proctor Crater on Mars: <span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> of dune-forming winds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fenton, Lori K.; Toigo, Anthony D.; Richardson, Mark I.</p> <p>2005-06-01</p> <p>Both atmospheric <span class="hlt">modeling</span> and spacecraft imagery of Mars are now of sufficient quality that the two can be used in conjunction to acquire an understanding of regional- and local-scale aeolian processes on Mars. We apply a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span> adapted for use on Mars (the Mars MM5) to Proctor Crater, a 150 km diameter crater in the southern highlands. Proctor Crater contains numerous aeolian features that indicate wind direction, including a large dark dune field with reversing transverse and star dunes containing three different slipface orientations, small and older bright bedforms that are most likely transverse granule ripples, and seasonally erased dust devil tracks. Results from <span class="hlt">model</span> runs spanning a Martian year, with a horizontal grid spacing of 10 km, predict winds aligned with two of the three dune slipfaces as well as spring and summer winds matching the dust devil track orientations. The primary (most prevalent) dune slipface orientation corresponds to a fall and winter westerly wind created by geostrophic forces. The tertiary dune slipface orientation is caused by spring and summer evening katabatic flows down the eastern rim of the crater, influencing only the eastern portion of the crater floor. The dunes are trapped in the crater because the tertiary winds, enhanced by topography, counter transport from the oppositely oriented primary winds, which may have originally carried sand into the crater. The dust devil tracks are caused by light spring and summer westerly winds during the early afternoon caused by planetary rotation. The secondary dune slipface orientation is not predicted by <span class="hlt">model</span> results from either the Mars MM5 or the Geophysical Fluid Dynamics Laboratory Mars general circulation <span class="hlt">model</span>. The reason for this is not clear, and the wind circulation pattern that creates this dune slipface is not well constrained. The Mars MM5 <span class="hlt">model</span> runs do not predict stresses above the saltation threshold for dune sand of the appropriate size and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007MAP....98...55V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007MAP....98...55V"><span id="translatedtitle">Simulation of heavy precipitation over Santacruz, Mumbai on 26 July 2005, using <span class="hlt">Mesoscale</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>Vaidya, S. S.; Kulkarni, J. R.</p> <p>2007-10-01</p> <p>An attempt has been made to simulate the unprecedented heavy precipitation of 94.4 cm in a day over Santacruz, Mumbai during 0300 UTC 26 July to 0300 UTC 27 July 2005. Three experiments have been conducted using Advanced Regional Prediction System <span class="hlt">model</span> developed by Center for Analysis and Prediction of Storms of Oklahoma University, USA. In first experiment the <span class="hlt">model</span> input at large domain size has been obtained using NCEP/NCAR reanalysis data at 2.5° × 2.5° lat. lon. resolution. In other two experiments <span class="hlt">model</span> input at large as well as at small domain sizes, have been obtained from NCEP/NCAR FNL data of 1° × 1° lat. lon. resolution. In all three experiments model’s horizontal resolution is 40 km and integration period is 30 hours from 0000 UTC 26 July 2005. Based on the temporal distribution of observed rainfall rates it is considered that the rainfall of 38.1 cm during 0900 1200 UTC on 26 July could be due to cloud burst phenomenon and 56.3 cm from 1200 UTC of 26 July to 0300 UTC of 27 July has been due to continuous regeneration of thunderstorm activity under influence of <span class="hlt">mesoscale</span> cloud complex. It is found that <span class="hlt">model</span> forecast of rainfall in first experiment was qualitatively as well as quantitatively very poor. Among other two, experiment with large domain size has predicted better rainfall values and location compared to the experiment with small domain size. The larger domain has produced rainfall of 41 cm as against observed rain rate of 56.3 cm. during 1200 UTC of 26 July to 0300 UTC of 27 July. Divergence, vorticity, vertical velocity and moisture parameters are examined in relation with the various stages of the event. The maximum values of convergence, vorticity and moisture fluxes precede the initial phase of mature stage, however vertical velocity follows the later phase of mature stage. Vorticity budget over the location of maximum rainfall, revealed the significant role of tilting term in maintenance and dissipation of the cloud complex</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMOS43B1543H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMOS43B1543H"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Eddies in the Solomon Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hristova, H. G.; Kessler, W. S.; McWilliams, J. C.; Molemaker, M. J.</p> <p>2011-12-01</p> <p>Water mass transformation in the strong equatorward flows through the Solomon Sea influences the properties of the Equatorial Undercurrent and subsequent cold tongue upwelling. High eddy activity in the interior Solomon Sea seen in altimetric sea surface height (SSH) and in several <span class="hlt">models</span> may provide a mechanism for these transformations. We investigate these effects using a <span class="hlt">mesoscale</span> (4-km resolution) sigma-coordinate (ROMS) <span class="hlt">model</span> of the Solomon Sea <span class="hlt">nested</span> in a basin solution, forced by a repeating seasonal cycle, and evaluated against observational data. The <span class="hlt">model</span> generates a vigorous upper layer eddy field; some of these are apparently shed as the New Guinea Coastal Undercurrent threads through the complex topography of the region, others are independent of the strong western boundary current. We diagnose the scales and vertical structure of the eddies in different parts of the Solomon Sea to illuminate their generation processes and propagation characteristics, and compare these to observed eddy statistics. Hypotheses tested are that the Solomon Sea <span class="hlt">mesoscale</span> eddies are generated locally by baroclinic instability, that the eddies are shed as the South Equatorial Current passes around and through the Solomon Island chain, that eddies are generated by the New Guinea Coastal Undercurrent, or that eddies occurring outside of the Solomon Sea propagate into the Solomon Sea. These different mechanisms have different implications for the resulting mixing and property fluxes. They also provide different interpretations for SSH signals observed from satellites (e.g., that will be observed by the upcoming SWOT satellite).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ems..confE.523G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ems..confE.523G"><span id="translatedtitle">Implementation of an improved urban parametrisation into the <span class="hlt">mesoscale</span> meteorology <span class="hlt">model</span> METRAS and application to London, UK</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grawe, D.; Thompson, H. L.; Salmond, J.; Cai, X.-M.; Schluenzen, K. H.</p> <p>2009-09-01</p> <p>Urban areas have well documented effects on thermal and dynamic properties of the air as well as its chemical composition. E.g. increased heat storage, anthropogenic heat sources and radiative trapping can cause increased temperatures in the urban canopy, leading to an urban heat island with potentially adverse effects on human health and comfort. A nocturnal heat island may exacerbate the impact of summer heat waves. With growing urbanisation and in a changing climate it can be expected that these effects will increase. In order to mitigate adverse effects of the urban heat island, the strength of the heat island needs to be assessed for current levels of urbanisation, as well as for prospective urbanisation scenarios. For this purpose, the <span class="hlt">mesoscale</span> meteorology <span class="hlt">model</span> METRAS (Schlünzen, 2003) has been extended by the urban canopy <span class="hlt">model</span> BEP (Martilli et al., 2002), which has previously been validated and implemented in other <span class="hlt">mesoscale</span> meteorology <span class="hlt">models</span>. BEP parameterises the effects of the urban canopy walls and surfaces on momentum, heat and turbulent kinetic energy and takes into account very detailed specifications of building parameters, such as building height distributions and street axis orientations. The implementation of BEP in METRAS allows the use of a separate numerical grid for BEP, so that for the <span class="hlt">model</span> simulations presented in this study a very fine vertical grid with 5m cell height (compared to 20m in the METRAS grid) could be used. Greater London forms the largest urban area within the UK and has therefore been selected as the focus area for the validation of results from the improved <span class="hlt">model</span> and for selected case studies. A domain covering 100km x 100km around London has been set up with a horizontal grid resolution of 1km x 1km. Results of the validation show that the inclusion of BEP improves the performance of METRAS for most cases when compared with measurements in the urban area. This improvement can ultimately be used to provide better</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=logistics+AND+center&pg=3&id=EJ959349','ERIC'); return false;" href="http://eric.ed.gov/?q=logistics+AND+center&pg=3&id=EJ959349"><span id="translatedtitle">Application of a Multidimensional <span class="hlt">Nested</span> Logit <span class="hlt">Model</span> to Multiple-Choice Test Items</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>Bolt, Daniel M.; Wollack, James A.; Suh, Youngsuk</p> <p>2012-01-01</p> <p><span class="hlt">Nested</span> logit <span class="hlt">models</span> have been presented as an alternative to multinomial logistic <span class="hlt">models</span> for multiple-choice test items (Suh and Bolt in "Psychometrika" 75:454-473, 2010) and possess a mathematical structure that naturally lends itself to evaluating the incremental information provided by attending to distractor selection in scoring. One potential…</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://eric.ed.gov/?q=simulation+AND+method+AND+mathematic&id=EJ1083301','ERIC'); return false;" href="http://eric.ed.gov/?q=simulation+AND+method+AND+mathematic&id=EJ1083301"><span id="translatedtitle">An Odds Ratio Approach for Detecting DDF under the <span class="hlt">Nested</span> Logit <span class="hlt">Modeling</span> Framework</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>Terzi, Ragip; Suh, Youngsuk</p> <p>2015-01-01</p> <p>An odds ratio approach (ORA) under the framework of a <span class="hlt">nested</span> logit <span class="hlt">model</span> was proposed for evaluating differential distractor functioning (DDF) in multiple-choice items and was compared with an existing ORA developed under the nominal response <span class="hlt">model</span>. The performances of the two ORAs for detecting DDF were investigated through an extensive…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A51D3069S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A51D3069S"><span id="translatedtitle">Forecast Verification for North American <span class="hlt">Mesoscale</span> (NAM) Operational <span class="hlt">Model</span> over Karst/Non-Karst regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sullivan, Z.; Fan, X.</p> <p>2014-12-01</p> <p>Karst is defined as a landscape that contains especially soluble rocks such as limestone, gypsum, and marble in which caves, underground water systems, over-time sinkholes, vertical shafts, and subterranean river systems form. The cavities and voids within a karst system affect the hydrology of the region and, consequently, can affect the moisture and energy budget at surface, the planetary boundary layer development, convection, and precipitation. Carbonate karst landscapes comprise about 40% of land areas over the continental U.S east of Tulsa, Oklahoma. Currently, due to the lack of knowledge of the effects karst has on the atmosphere, no existing weather <span class="hlt">model</span> has the capability to represent karst landscapes and to simulate its impact. One way to check the impact of a karst region on the atmosphere is to check the performance of existing weather <span class="hlt">models</span> over karst and non-karst regions. The North American <span class="hlt">Mesoscale</span> (NAM) operational forecast is the best example, of which historical forecasts were archived. Variables such as precipitation, maximum/minimum temperature, dew point, evapotranspiration, and surface winds were taken into account when checking the <span class="hlt">model</span> performance over karst versus non-karst regions. The forecast verification focused on a five-year period from 2007-2011. Surface station observations, gridded observational dataset, and North American Regional Reanalysis (for certain variables with insufficient observations) were used. Thirteen regions of differing climate, size, and landscape compositions were chosen across the Contiguous United States (CONUS) for the investigation. Equitable threat score (ETS), frequency bias (fBias), and root-mean-square error (RMSE) scores were calculated and analyzed for precipitation. RMSE and mean bias (Bias) were analyzed for other variables. ETS, fBias, and RMSE scores show generally a pattern of lower forecast skills, a greater magnitude of error, and a greater under prediction of precipitation over karst than</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A33J0321S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A33J0321S"><span id="translatedtitle">Short-term Climate Simulations of African Easterly Waves with a Global <span class="hlt">Mesoscale</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>Shen, B. W.</p> <p>2015-12-01</p> <p>Recent high-resolution global <span class="hlt">model</span> simulations ( Shen et al., 2010a, 2010b, 2012; 2013), which were conducted to examine the role of multiscale processes associated with tropical waves in the predictability of <span class="hlt">mesoscale</span> tropical cyclones (TCs), suggested that a large-scale system (e.g., tropical waves) can provide determinism on the prediction of TC genesis, making it possible to extend the lead time of genesis predictions. Selected cases include the relationship between (i) TC Nargis (2008) and an Equatorial Rossby wave; (ii) Hurricane Helene (2006) and an intensifying African Easterly Wave (AEW); (iii) Twin TCs (2002) and a mixed Rossby-gravity wave during an active phase of the Madden Julian Oscillation (MJO); (iv) Hurricane Sandy (2012) and tropical waves during an active phase of the MJO. In this talk, thirty-day simulations with different <span class="hlt">model</span> configurations are presented to examine the <span class="hlt">model</span>'s ability to simulate AEWs and MJOs and their association with tropical cyclogenesis. I will first discuss the simulations of the initiation and propagation of 6 consecutive AEWs in late August 2006 and the mean state of the African easterly jet (AEJ) over both Africa and downstream in the tropical Atlantic. By comparing our simulations with NCEP analysis and satellite data (e.g., TRMM), it is shown that the statistical characteristics of individual AEWs are realistically simulated with larger errors in the 5th and th AEWs. Results from the sensitivity experiments suggest the following: 1) accurate representations of non-linear interactions between the atmosphere and land processes are crucial for improving the simulations of the AEWs and the AEJ; 2) improved simulations of an individual AEW and its interaction with local environments (e.g., the Guinea Highlands) could provide determinism for hurricane formation downstream. Of interest is the potential to extend the lead time for predicting hurricane formation (e.g., a lead time of up to 22 days) as the 4th AEW is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA322694','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA322694"><span id="translatedtitle">Habitat Suitability Index <span class="hlt">Models</span>: Diamondback Terrapin (<span class="hlt">Nesting</span>)--Atlantic Coast.</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>1988-03-01</p> <p>The diamondback terrapin occurs in a narrow strip of salt and brackish water habitats along the Atlantic and gulf coasts of the United States. A...review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) <span class="hlt">model</span> for the diamondback terrapin (Malaclemys... terrapin ). The <span class="hlt">model</span> is scaled to produce an index between 0.0 (unsuitable habitat) and 1.0 (optimum habitat). HSI <span class="hlt">models</span> are designed to be used with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://archive.usgs.gov/archive/sites/www.nwrc.usgs.gov/wdb/pub/hsi/hsi-151.pdf','USGSPUBS'); return false;" href="https://archive.usgs.gov/archive/sites/www.nwrc.usgs.gov/wdb/pub/hsi/hsi-151.pdf"><span id="translatedtitle">Habitat Suitability Index <span class="hlt">Models</span>: Diamondback terrapin (<span class="hlt">nesting</span>) - Atlantic coast</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Palmer, William M.; Cordes, Carroll L.</p> <p>1988-01-01</p> <p>A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) <span class="hlt">model</span> for the diamondback terrapin (Malaclemys terrapin). The <span class="hlt">model</span> consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI <span class="hlt">models</span> are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26113190','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26113190"><span id="translatedtitle">A simple, physiologically-based <span class="hlt">model</span> of sea turtle remigration intervals and <span class="hlt">nesting</span> population dynamics: Effects of temperature.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Neeman, Noga; Spotila, James R; O'Connor, Michael P</p> <p>2015-09-07</p> <p>Variation in the yearly number of sea turtles <span class="hlt">nesting</span> at rookeries can interfere with population estimates and obscure real population dynamics. Previous theoretical <span class="hlt">models</span> suggested that this variation in <span class="hlt">nesting</span> numbers may be driven by changes in resources at the foraging grounds. We developed a physiologically-based <span class="hlt">model</span> that uses temperatures at foraging sites to predict foraging conditions, resource accumulation, remigration probabilities, and, ultimately, <span class="hlt">nesting</span> numbers for a stable population of sea turtles. We used this <span class="hlt">model</span> to explore several scenarios of temperature variation at the foraging grounds, including one-year perturbations and cyclical temperature oscillations. We found that thermally driven resource variation can indeed synchronize <span class="hlt">nesting</span> in groups of turtles, creating cohorts, but that these cohorts tend to break down over 5-10 years unless regenerated by environmental conditions. Cohorts were broken down faster at lower temperatures. One-year perturbations of low temperature had a synchronizing effect on <span class="hlt">nesting</span> the following year, while high temperature perturbations tended to delay <span class="hlt">nesting</span> in a less synchronized way. Cyclical temperatures lead to cyclical responses both in <span class="hlt">nesting</span> numbers and remigration intervals, with the amplitude and lag of the response depending on the duration of the cycle. Overall, <span class="hlt">model</span> behavior is consistent with observations at <span class="hlt">nesting</span> beaches. Future work should focus on refining the <span class="hlt">model</span> to fit particular <span class="hlt">nesting</span> populations and testing further whether or not it may be used to predict observed <span class="hlt">nesting</span> numbers and remigration intervals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1480M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1480M"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modelling</span> methodology based on nudging to increase accuracy in WRA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mylonas Dirdiris, Markos; Barbouchi, Sami; Hermmann, Hugo</p> <p>2016-04-01</p> <p>The offshore wind energy has recently become a rapidly growing renewable energy resource worldwide, with several offshore wind projects in development in different planning stages. Despite of this, a better understanding of the atmospheric interaction within the marine atmospheric boundary layer (MABL) is needed in order to contribute to a better energy capture and cost-effectiveness. Light has been thrown in observational nudging as it has recently become an innovative method to increase the accuracy of wind flow <span class="hlt">modelling</span>. This particular study focuses on the observational nudging capability of Weather Research and Forecasting (WRF) and ways the uncertainty of wind flow <span class="hlt">modelling</span> in the wind resource assessment (WRA) can be reduced. Finally, an alternative way to calculate the <span class="hlt">model</span> uncertainty is pinpointed. Approach WRF <span class="hlt">mesoscale</span> <span class="hlt">model</span> will be nudged with observations from FINO3 at three different heights. The <span class="hlt">model</span> simulations with and without applying observational nudging will be verified against FINO1 measurement data at 100m. In order to evaluate the observational nudging capability of WRF two ways to derive the <span class="hlt">model</span> uncertainty will be described: one global uncertainty and an uncertainty per wind speed bin derived using the recommended practice of the IEA in order to link the <span class="hlt">model</span> uncertainty to a wind energy production uncertainty. This study assesses the observational data assimilation capability of WRF <span class="hlt">model</span> within the same vertical gridded atmospheric column. The principal aim is to investigate whether having observations up to one height could improve the simulation at a higher vertical level. The study will use objective analysis implementing a Cress-man scheme interpolation to interpolate the observation in time and in sp ace (keeping the horizontal component constant) to the gridded analysis. Then the WRF <span class="hlt">model</span> core will incorporate the interpolated variables to the "first guess" to develop a nudged simulation. Consequently, WRF with and without</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.C11C0394E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.C11C0394E"><span id="translatedtitle"><span class="hlt">Meso-Scale</span> Hydrological <span class="hlt">Modeling</span> Using Small Scale Parameterizations in a Discontinuous Permafrost Watershed in the Boreal Forest Ecosystem</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Endalamaw, A. M.; Bolton, W. R.; Hinzman, L. D.; Morton, D.; Young, J. M.</p> <p>2014-12-01</p> <p>The sub-Arctic region lies in the transition zone between the warm temperate region to the south and the cold arctic region to the north. The sub-Arctic hosts sharply contrasting ecosystems that vary over short horizontal spatial scales due to the presence or absence of permafrost. In the discontinuous permafrost zone, the presence or absence of permafrost plays a dominant role to many hydrological processes including stream flow, soil moisture, and water storage dynamics. The distribution of permafrost also has a strong influence on ecosystem composition and function. The land cover and vegetation distribution is also an important parameter affecting the stream flow responses due to the large differences in the transpiration rates between coniferous and deciduous vegetation. As a result, accurate simulation of the hydrology in this region is challenging. The objectives of this study are to improve the parameterization of <span class="hlt">meso-scale</span> hydrologic simulations in the discontinuous permafrost zone through fine-scale observation and <span class="hlt">modeling</span>. Slope and aspect, derived from 30m Digital Elevation <span class="hlt">Model</span> (DEM), are used as a proxy for permafrost distribution and vegetation composition. Small-scale parameterizations were conducted at the two sub-basins (area ~11km2 ) of the Caribou-Poker Creeks Research Watershed (CPCRW) using the Variable Infiltration Capacity (VIC) <span class="hlt">meso-scale</span> hydrological <span class="hlt">model</span>. The small scale parameterization simulation results indicate that slope and aspect based vegetation cover and soil parameter parameterization improve <span class="hlt">meso-scale</span> hydrological <span class="hlt">modeling</span> in these regions. In order to test the extent to which these small-scale parameterizations are valid, the Chena River Basin (area ~5,478 km2), located in Interior Alaska, is being simulated using these small-scale parameterizations. Aspect will be used as the proxy for the parameterization of vegetation cover and soil property. Results from the VIC simulation using the small scale parameterization will</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1612778L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1612778L"><span id="translatedtitle">Management <span class="hlt">model</span> application at <span class="hlt">nested</span> spatial levels in Mediterranean Basins</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lo Porto, Antonio; De Girolamo, Anna Maria; Froebrich, Jochen</p> <p>2014-05-01</p> <p>In the EU Water Framework Directive (WFD) implementation processes, hydrological and water quality <span class="hlt">models</span> can be powerful tools that allow to design and test alternative management strategies, as well as judging their general feasibility and acceptance. Although in recent decades several <span class="hlt">models</span> have been developed, their use in Mediterranean basins, where rivers have a temporary character, is quite complex and there is limited information in literature which can facilitate <span class="hlt">model</span> applications and result evaluations in this region. The high spatial variability which characterizes rainfall events, soil hydrological properties and land uses of Mediterranean basin makes more difficult to simulate hydrological and water quality in this region than in other Countries. This variability also has several implications in <span class="hlt">modeling</span> simulations results especially when simulations at different spatial scale are needed for watershed management purpose. It is well known that environmental processes operating at different spatial scale determine diverse impacts on water quality status (hydrological, chemical, ecological). Hence, the development of management strategies have to include both large scale (watershed) and local spatial scales approaches (e.g. stream reach). This paper presents the results of a study which analyzes how the spatial scale affects the results of hydrologic process and water quality of <span class="hlt">model</span> simulations in a Mediterranean watershed. Several aspects involved in <span class="hlt">modeling</span> hydrological and water quality processes at different spatial scale for river basin management are investigated including <span class="hlt">model</span> data requirements, data availability, <span class="hlt">model</span> results and uncertainty. A hydrologic and water quality <span class="hlt">model</span> (SWAT) was used to simulate hydrologic processes and water quality at different spatial scales in the Candelaro river basin (Puglia, S-E Italy) and to design management strategies to reach as possible WFD goals. When studying a basin to assess its current status</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25738766','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25738766"><span id="translatedtitle">Detection of bird <span class="hlt">nests</span> during mechanical weeding by incremental background <span class="hlt">modeling</span> and visual saliency.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Steen, Kim Arild; Therkildsen, Ole Roland; Green, Ole; Karstoft, Henrik</p> <p>2015-03-02</p> <p>Mechanical weeding is an important tool in organic farming. However, the use of mechanical weeding in conventional agriculture is increasing, due to public demands to lower the use of pesticides and an increased number of pesticide-resistant weeds. Ground <span class="hlt">nesting</span> birds are highly susceptible to farming operations, like mechanical weeding, which may destroy the <span class="hlt">nests</span> and reduce the survival of chicks and incubating females. This problem has limited focus within agricultural engineering. However, when the number of machines increases, destruction of <span class="hlt">nests</span> will have an impact on various species. It is therefore necessary to explore and develop new technology in order to avoid these negative ethical consequences. This paper presents a vision-based approach to automated ground <span class="hlt">nest</span> detection. The algorithm is based on the fusion of visual saliency, which mimics human attention, and incremental background <span class="hlt">modeling</span>, which enables foreground detection with moving cameras. The algorithm achieves a good detection rate, as it detects 28 of 30 <span class="hlt">nests</span> at an average distance of 3.8 m, with a true positive rate of 0.75.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1127267','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1127267"><span id="translatedtitle">Using <span class="hlt">Mesoscale</span> Weather <span class="hlt">Model</span> Output as Boundary Conditions for Atmospheric Large-Eddy Simulations and Wind-Plant Aerodynamic Simulations (Presentation)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Churchfield, M. J.; Michalakes, J.; Vanderwende, B.; Lee, S.; Sprague, M. A.; Lundquist, J. K.; Moriarty, P. J.</p> <p>2013-10-01</p> <p>Wind plant aerodynamics are directly affected by the microscale weather, which is directly influenced by the <span class="hlt">mesoscale</span> weather. Microscale weather refers to processes that occur within the atmospheric boundary layer with the largest scales being a few hundred meters to a few kilometers depending on the atmospheric stability of the boundary layer. <span class="hlt">Mesoscale</span> weather refers to large weather patterns, such as weather fronts, with the largest scales being hundreds of kilometers wide. Sometimes microscale simulations that capture <span class="hlt">mesoscale</span>-driven variations (changes in wind speed and direction over time or across the spatial extent of a wind plant) are important in wind plant analysis. In this paper, we present our preliminary work in coupling a <span class="hlt">mesoscale</span> weather <span class="hlt">model</span> with a microscale atmospheric large-eddy simulation <span class="hlt">model</span>. The coupling is one-way beginning with the weather <span class="hlt">model</span> and ending with a computational fluid dynamics solver using the weather <span class="hlt">model</span> in coarse large-eddy simulation mode as an intermediary. We simulate one hour of daytime moderately convective microscale development driven by the <span class="hlt">mesoscale</span> data, which are applied as initial and boundary conditions to the microscale domain, at a site in Iowa. We analyze the time and distance necessary for the smallest resolvable microscales to develop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.P22A..05L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.P22A..05L"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> of Water Vapor and Dust in Valles Marineris: Atmospheric Influences on Recurring Slope Lineae.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leung, C. W. S.; Rafkin, S. C.; McEwen, A. S.</p> <p>2015-12-01</p> <p>Extensive recurring slope lineae (RSL) activity has been detected in Valles Marineris on Mars and coincides with regions where water ice fogs appear [1]. The origin of the water driving RSL flow is not well understood, but observational evidence suggests atmospheric processes play a crucial role [2]. Provided the atmospheric vapor concentration is high enough, water ice fogs can form overnight if the surface temperature cools below the condensation temperature. Correlations between dust storms and flow rates suggest that atmospheric dust opacity, and its influence on air temperature, also has a significant effect on RSL activity. We investigate planetary boundary layer processes that govern the hydrological cycle and dust cycle on Mars using a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span> to simulate the distribution of water and dust with respect to regional atmospheric circulations. Our simulations in Valles Marineris show a curious temperature structure, where the inside of the canyon appears warmer relative to the plateaus immediately outside. For a well-mixed atmosphere, this temperature structure indicates that when the atmosphere inside the canyon is saturated and fog is present within Valles Marineris, fog and low-lying clouds should also be present on the cooler surrounding plateaus as well. However, images taken with the Mars Express High Resolution Stereo Camera (HRSC) show instances where water ice fog appeared exclusively inside the canyon. These results have important implications for the origin and concentration of water vapor in Valles Marineris, with possible connections to RSL. The potential temperatures from our simulations show a high level of stability inside the canyon produced dynamically by sinking air. However, afternoon updrafts along the canyon walls indicate that over time, water vapor within the chasm would escape along the sides of the canyon. Again, this suggests a local source or mechanism to concentrate water vapor is needed to explain the fog</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://elibrary.unm.edu/sora/Wilson/v093n01/p0042-p0053.pdf','USGSPUBS'); return false;" href="http://elibrary.unm.edu/sora/Wilson/v093n01/p0042-p0053.pdf"><span id="translatedtitle">The Mayfield method of estimating <span class="hlt">nesting</span> success: A <span class="hlt">model</span>, estimators and simulation results</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hensler, G.L.; Nichols, J.D.</p> <p>1981-01-01</p> <p>Using a <span class="hlt">nesting</span> <span class="hlt">model</span> proposed by Mayfield we show that the estimator he proposes is a maximum likelihood estimator (m.l.e.). M.l.e. theory allows us to calculate the asymptotic distribution of this estimator, and we propose an estimator of the asymptotic variance. Using these estimators we give approximate confidence intervals and tests of significance for daily survival. Monte Carlo simulation results show the performance of our estimators and tests under many sets of conditions. A traditional estimator of <span class="hlt">nesting</span> success is shown to be quite inferior to the Mayfield estimator. We give sample sizes required for a given accuracy under several sets of conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015FlDyR..47e1401I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015FlDyR..47e1401I"><span id="translatedtitle">Variational data assimilation system with <span class="hlt">nesting</span> <span class="hlt">model</span> for high resolution ocean circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ishikawa, Yoichi; In, Teiji; Nakada, Satoshi; Nishina, Kei; Igarashi, Hiromichi; Hiyoshi, Yoshimasa; Sasaki, Yuji; Wakamatsu, Tsuyoshi; Awaji, Toshiyuki</p> <p>2015-10-01</p> <p>To obtain the high-resolution analysis fields for ocean circulation, a new incremental approach is developed using a four-dimensional variational data assimilation system with <span class="hlt">nesting</span> <span class="hlt">models</span>. The results show that there are substantial biases when using a classical method combined with data assimilation and downscaling, caused by different dynamics resulting from the different resolutions of the <span class="hlt">models</span> used within the <span class="hlt">nesting</span> <span class="hlt">models</span>. However, a remarkable reduction in biases of the low-resolution <span class="hlt">model</span> relative to the high-resolution <span class="hlt">model</span> was observed using our new approach in narrow strait regions, such as the Tsushima and Tsugaru straits, where the difference in the dynamics represented by the high- and low-resolution <span class="hlt">models</span> is substantial. In addition, error reductions are demonstrated in the downstream region of these narrow channels associated with the propagation of information through the <span class="hlt">model</span> dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA....12419A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA....12419A"><span id="translatedtitle">Diagnosis of precipitation variability in <span class="hlt">nested</span> regional climate <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>Arritt, R.; PIRCS Participants</p> <p>2003-04-01</p> <p>In order to assess reasons for <span class="hlt">model-to-model</span> variability of precipitation in regional climate <span class="hlt">models</span> (RCMs) we have evaluated 60-day simulations over the continental U.S. in June-July 1993 from thirteen simulations using different RCMs. The hydrologic cycles in the simulations were compared both to each other and to observations for a subregion of the upper Mississippi River Basin (UMRB), containing the region of maximum 60-day accumulated precipitation in all RCMs and station reports. All RCMs produced positive precipitation (P) minus evaporation (E) and recycling ratios that were within the range estimated from observations. RCM E was sensitive to radiation parameterization, but inter-<span class="hlt">model</span> variability of E was spread evenly about estimates of observed E. In contrast, most RCMs produced P that was below the range of P from observations, accounting for the low values of simulated P-E compared to observations. Nine of the 13 RCMs reproduced qualitatively the observed daily cycles of P and moisture flux convergence (C), with maximum P and C occurring simultaneously at night. Three of the four driest RCMs had maximum precipitation in the afternoon, suggesting that in these RCMs afternoon destabilization by insolation had excessive influence on production of precipitation. Thus a key indicator of the ability of RCMs in this collection to properly simulate P is their ability to simulate the observed nocturnal maximum of P, indicating that the failure to resolve the diurnal cycle is closely related to overall bias in precipitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=ulrich+AND+model&pg=3&id=EJ910601','ERIC'); return false;" href="http://eric.ed.gov/?q=ulrich+AND+model&pg=3&id=EJ910601"><span id="translatedtitle">The Structure of Academic Self-Concepts Revisited: The <span class="hlt">Nested</span> Marsh/Shavelson <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>Brunner, Martin; Keller, Ulrich; Dierendonck, Christophe; Reichert, Monique; Ugen, Sonja; Fischbach, Antoine; Martin, Romain</p> <p>2010-01-01</p> <p>The <span class="hlt">nested</span> Marsh/Shavelson (NMS) <span class="hlt">model</span> integrates structural characteristics of academic self-concepts that have proved empirically incompatible in previous studies. Specifically, it conceives of academic self-concepts to be subject specific, strongly separated across domains, and hierarchically organized, with general academic self-concept at the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=266456&keyword=Breeding&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=90574894&CFTOKEN=61790817','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=266456&keyword=Breeding&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=90574894&CFTOKEN=61790817"><span id="translatedtitle">Avian life history profiles for use in the Markov chain <span class="hlt">nest</span> productivity <span class="hlt">model</span> (MCnest)</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 Markov Chain <span class="hlt">nest</span> productivity <span class="hlt">model</span>, or MCnest, quantitatively estimates the effects of pesticides or other toxic chemicals on annual reproductive success of avian species (Bennett and Etterson 2013, Etterson and Bennett 2013). The Basic Version of MCnest was developed as a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26543578','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26543578"><span id="translatedtitle">Computational <span class="hlt">model</span> of collective <span class="hlt">nest</span> selection by ants with heterogeneous acceptance thresholds.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Masuda, Naoki; O'shea-Wheller, Thomas A; Doran, Carolina; Franks, Nigel R</p> <p>2015-06-01</p> <p>Collective decision-making is a characteristic of societies ranging from ants to humans. The ant Temnothorax albipennis is known to use quorum sensing to collectively decide on a new home; emigration to a new <span class="hlt">nest</span> site occurs when the number of ants favouring the new site becomes quorate. There are several possible mechanisms by which ant colonies can select the best <span class="hlt">nest</span> site among alternatives based on a quorum mechanism. In this study, we use computational <span class="hlt">models</span> to examine the implications of heterogeneous acceptance thresholds across individual ants in collective <span class="hlt">nest</span> choice behaviour. We take a minimalist approach to develop a differential equation <span class="hlt">model</span> and a corresponding non-spatial agent-based <span class="hlt">model</span>. We show, consistent with existing empirical evidence, that heterogeneity in acceptance thresholds is a viable mechanism for efficient <span class="hlt">nest</span> choice behaviour. In particular, we show that the proposed <span class="hlt">models</span> show speed-accuracy trade-offs and speed-cohesion trade-offs when we vary the number of scouts or the quorum threshold.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11..933H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11..933H"><span id="translatedtitle">Coastal (Sub)<span class="hlt">Mesoscale</span> Eddies in the Gulf of Lion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Z. Y.; Doglioli, A. M.; Petrenko, A. A.; Marsaleix, P.; Dekeyser, I.</p> <p>2009-04-01</p> <p>The LAgrangian Transport EXperiment (LATEX) project (2008-2011) has been initiated in order to study the role of (sub)<span class="hlt">mesoscale</span> structures on shelf-offshore exchanges in the Gulf of Lion. The strategy will combine use of data from an inert tracer release (SF6), Lagrangian drifters, satellites and Eulerian moorings with numerical <span class="hlt">modeling</span>. In this work, we present a shelf-scale <span class="hlt">model</span> of high resolution (1-km) <span class="hlt">nested</span> in a regional-scale <span class="hlt">model</span> (3-km). We use an upwind-type advection-diffusion scheme, in which the numerical diffusion term is adjusted by an attenuation coefficient. Sensitivity tests have been carried out, varying the <span class="hlt">model</span> spatial resolution and the attenuation coefficient to reproduce the (sub)<span class="hlt">mesoscale</span> structures. A wavelet technique is applied on <span class="hlt">model</span> outputs to identify eddies and to define their area, position and tracking duration. Comparisons between the <span class="hlt">modeled</span> eddies and those observed by satellite have allowed us to choose the best <span class="hlt">model</span> configuration. With this setup, single and combined effects of wind forcing, bathymetry and <span class="hlt">mesoscale</span> circulation are investigated to propose a generation process of these simulated eddies. Then, simulations are run for long period to obtain annual variability and statistics of the coastal eddies. These coastal (sub)<span class="hlt">mesoscale</span> eddies potentially interact with the distal plume of the Rhône river and the Northern Current. Numerical <span class="hlt">modeling</span> sets the foundation to understand the eddies' dynamics and helps us set up the sampling strategy of the cruises. The in situ measurements combined with the <span class="hlt">modeling</span> results will allow us to evaluate the eddies' potential impact on the coastal-offshore transfer of matter and energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840043466&hterms=Weather+forecasting&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DWeather%2Bforecasting','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840043466&hterms=Weather+forecasting&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DWeather%2Bforecasting"><span id="translatedtitle">A <span class="hlt">nested</span>-grid limited-area <span class="hlt">model</span> for short term weather forecasting</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wong, V. C.; Zack, J. W.; Kaplan, M. L.; Coats, G. D.</p> <p>1983-01-01</p> <p>The present investigation is concerned with a <span class="hlt">mesoscale</span> atmospheric simulation system (MASS), incorporating the sigma-coordinate primitive equations. The present version of this <span class="hlt">model</span> (MASS 3.0) has 14 vertical layers, with the upper boundary at 100 mb. There are 128 x 96 grid points in each layer. The earlier version of this <span class="hlt">model</span> (MASS 2.0) has been described by Kaplan et al. (1982). The current investigation provides a summary of major revisions to that version and a description of the parameterization schemes which are presently included in the <span class="hlt">model</span>. The planetary boundary layer (PBL) is considered, taking into account aspects of generalized similarity theory and free convection, the surface energy budget, the surface moisture budget, and prognostic equations for the depth h of the PBL. A cloud <span class="hlt">model</span> is discussed, giving attention to stable precipitation, and cumulus convection.</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('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4084988','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4084988"><span id="translatedtitle">Food Provisioning and Parental Status in Songbirds: Can Occupancy <span class="hlt">Models</span> Be Used to Estimate <span class="hlt">Nesting</span> Performance?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Corbani, Aude Catherine; Hachey, Marie-Hélène; Desrochers, André</p> <p>2014-01-01</p> <p>Indirect methods to estimate parental status, such as the observation of parental provisioning, have been problematic due to potential biases associated with imperfect detection. We developed a method to evaluate parental status based on a novel combination of parental provisioning observations and hierarchical <span class="hlt">modeling</span>. In the summers of 2009 to 2011, we surveyed 393 sites, each on three to four consecutive days at Forêt Montmorency, Québec, Canada. We assessed parental status of 2331 adult songbirds based on parental food provisioning. To account for imperfect detection of parental status, we applied MacKenzie et al.'s (2002) two-state hierarchical <span class="hlt">model</span> to obtain unbiased estimates of the proportion of sites with successfully <span class="hlt">nesting</span> birds, and the proportion of adults with offspring. To obtain an independent evaluation of detection probability, we monitored 16 active <span class="hlt">nests</span> in 2010 and conducted parental provisioning observations away from them. The probability of detecting food provisioning was 0.31 when using <span class="hlt">nest</span> monitoring, a value within the 0.11 to 0.38 range that was estimated by two-state <span class="hlt">models</span>. The proportion of adults or sites with broods approached 0.90 and varied depending on date during the sampling season and year, exemplifying the role of eastern boreal forests as highly productive <span class="hlt">nesting</span> grounds for songbirds. This study offers a simple and effective sampling design for studying avian reproductive performance that could be implemented in national surveys such as breeding bird atlases. PMID:24999969</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24999969','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24999969"><span id="translatedtitle">Food provisioning and parental status in songbirds: can occupancy <span class="hlt">models</span> be used to estimate <span class="hlt">nesting</span> performance?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Corbani, Aude Catherine; Hachey, Marie-Hélène; Desrochers, André</p> <p>2014-01-01</p> <p>Indirect methods to estimate parental status, such as the observation of parental provisioning, have been problematic due to potential biases associated with imperfect detection. We developed a method to evaluate parental status based on a novel combination of parental provisioning observations and hierarchical <span class="hlt">modeling</span>. In the summers of 2009 to 2011, we surveyed 393 sites, each on three to four consecutive days at Forêt Montmorency, Québec, Canada. We assessed parental status of 2331 adult songbirds based on parental food provisioning. To account for imperfect detection of parental status, we applied MacKenzie et al.'s (2002) two-state hierarchical <span class="hlt">model</span> to obtain unbiased estimates of the proportion of sites with successfully <span class="hlt">nesting</span> birds, and the proportion of adults with offspring. To obtain an independent evaluation of detection probability, we monitored 16 active <span class="hlt">nests</span> in 2010 and conducted parental provisioning observations away from them. The probability of detecting food provisioning was 0.31 when using <span class="hlt">nest</span> monitoring, a value within the 0.11 to 0.38 range that was estimated by two-state <span class="hlt">models</span>. The proportion of adults or sites with broods approached 0.90 and varied depending on date during the sampling season and year, exemplifying the role of eastern boreal forests as highly productive <span class="hlt">nesting</span> grounds for songbirds. This study offers a simple and effective sampling design for studying avian reproductive performance that could be implemented in national surveys such as breeding bird atlases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030063974','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030063974"><span id="translatedtitle">A New Objective Technique for Verifying <span class="hlt">Mesoscale</span> Numerical Weather Prediction <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>Case, Jonathan L.; Manobianco, John; Lane, John E.; Immer, Christopher D.</p> <p>2003-01-01</p> <p>This report presents a new objective technique to verify predictions of the sea-breeze phenomenon over east-central Florida by the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS) <span class="hlt">mesoscale</span> numerical weather prediction (NWP) <span class="hlt">model</span>. The Contour Error Map (CEM) technique identifies sea-breeze transition times in objectively-analyzed grids of observed and forecast wind, verifies the forecast sea-breeze transition times against the observed times, and computes the mean post-sea breeze wind direction and speed to compare the observed and forecast winds behind the sea-breeze front. The CEM technique is superior to traditional objective verification techniques and previously-used subjective verification methodologies because: It is automated, requiring little manual intervention, It accounts for both spatial and temporal scales and variations, It accurately identifies and verifies the sea-breeze transition times, and It provides verification contour maps and simple statistical parameters for easy interpretation. The CEM uses a parallel lowpass boxcar filter and a high-order bandpass filter to identify the sea-breeze transition times in the observed and <span class="hlt">model</span> grid points. Once the transition times are identified, CEM fits a Gaussian histogram function to the actual histogram of transition time differences between the <span class="hlt">model</span> and observations. The fitted parameters of the Gaussian function subsequently explain the timing bias and variance of the timing differences across the valid comparison domain. Once the transition times are all identified at each grid point, the CEM computes the mean wind direction and speed during the remainder of the day for all times and grid points after the sea-breeze transition time. The CEM technique performed quite well when compared to independent meteorological assessments of the sea-breeze transition times and results from a previously published subjective evaluation. The algorithm correctly identified a forecast or observed sea-breeze occurrence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.B31D0340J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.B31D0340J"><span id="translatedtitle">Quantification of Biosphere and Anthropogenic CO2 using WRF-VPRM <span class="hlt">Mesoscale</span> Transport and Biosphere <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>Jamroensan, A.; Ahmadov, R.; Petron, G.; Carmichael, G. R.; Andrews, A. E.; Sweeney, C.; Kretschmer, R.; Gerbig, C.; Olsen, L. M.; Stanier, C. O.</p> <p>2010-12-01</p> <p>Understanding of carbon dioxide (CO2) regional sources and sinks is crucial for estimating current and future carbon budgets. Here, we evaluate the skill of a diagnostic biosphere <span class="hlt">model</span>, Vegetation Photosynthesis and Respiration <span class="hlt">Model</span>, VPRM, online-coupled with the <span class="hlt">mesoscale</span> Weather Research and Forecasting <span class="hlt">model</span> WRF to simulate CO2 biosphere fluxes and total CO2 concentrations in the Midwest, USA with high spatial resolution (4km x 4km horizontally, 30 vertical levels of which 9 are below 1.5 km). Extensive evaluation data and bottom up inventories are available for this area and period from the Mid Continent Intensive (e.g. RING2 measurements, http://www.ring2.psu.edu/) Preliminary results of July 2008 yield average net fluxes over the State of Iowa of NEE in June, July, and August 2008 of -0.7 µmol/m2, -5.8 µmol/m2, and -6.3 µmol/m2, respectively. Results at two Ameriflux sites in Ames, Iowa (Brook Field sites 10 and 11), with the current VPRM parameters simulated lower GEE and respiration fluxes compared to fluxes of NOAA Carbon Tracker products and observations. While absolute values of gross fluxes in WRF-VPRM are lower than the limited observations and Carbon Tracker, the net flux in WRF-VPRM generally exceeds that of Carbon Tracker for the summer 2008 period. CO2 concentrations simulated with the above fluxes and 4-km WRF-VPRM were compared to hourly CO2 data from NOAA tall tower at West Branch Iowa (WBI). Vulcan anthropogenic emissions (Gurney, 2009) were used included as well together with initial condition and boundary condition from Carbon Tracker (Peters et al, 2007) so as to give a simulated total CO2 concentration. Two planetary boundary layer schemes, YSU and MYJ, in WRF version 3.0.1 were tested in these CO2 simulations. The MYJ scheme predicted better results for wind speed and wind direction than YSU scheme. When compared to CO2 measurement at WBI (hourly average at 30m, 99m, and 379m above ground), both schemes performed similarly, with the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/940149','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/940149"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> of irreversible volume growth in powders of anisotropic crystals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gee, R; Maiti, A; Fried, L</p> <p>2006-05-05</p> <p>Careful thermometric analysis (TMA) on powders of micron-sized triamino-trinitrobenzene (TATB) crystallites are shown to display irreversible growth in volume when subjected to repeated cycles of heating and cooling. Such behavior is counter-intuitive to typical materials response to simulated annealing cycles in atomic-scale molecular dynamics. However, through coarse-grained simulations using a <span class="hlt">mesoscale</span> Hamiltonian we quantitatively reproduce irreversible growth behavior in such powdered material. We demonstrate that irreversible growth happens only in the presence of intrinsic crystalline anisotropy, and is mediated by particles much smaller than the average crystallite size.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850054706&hterms=assimilation+methods&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dassimilation%2Bmethods','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850054706&hterms=assimilation+methods&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dassimilation%2Bmethods"><span id="translatedtitle">Variational assimilation of VAS data into a <span class="hlt">mesoscale</span> <span class="hlt">model</span> Assimilation method and sensitivity experiments. [Visible Infrared Spin-Scan Radiometer Atmospheric Sounder</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cram, J. M.; Kaplan, M. L.</p> <p>1985-01-01</p> <p>The assimilation of temperature and moisture gradient information from the Visible IR Spin-Scan Radiometer's Atmospheric Sounder (VAS) into a <span class="hlt">mesoscale</span> <span class="hlt">model</span> is presently undertaken by means of a variational method and followed by tests of the sensitivity of both diabatic and adiabatic versions of the <span class="hlt">model</span> to VAS data assimilations for the case of July 20-21, 1981. The synoptic scale effects of the assimilation of VAS data are noted to be negligible; the greatest impact was instead on <span class="hlt">mesoscale</span> forecasts of convective instability patterns. The additional assimilation of relative humidity gradients did not significantly change the patterns of the forecast instabilities. The greatest improvements from assimilation resulted from the resolution of the strong <span class="hlt">mesoscale</span> temperature gradients by the asynoptic VAS data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1712530K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1712530K"><span id="translatedtitle">Wind Power Energy in Southern Brazil: evaluation using a <span class="hlt">mesoscale</span> meteorological <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>Krusche, Nisia; Stoevesandt, Bernhard; Chang, Chi-Yao; Peralta, Carlos</p> <p>2015-04-01</p> <p>In recent years, several wind farms were build in the coast of Rio Grande do Sul state. This region of Brazil was identified, in wind energy studies, as most favorable to the development of wind power energy, along with the Northeast part of the country. Site assessments of wind power, over long periods to estimate the power production and forecasts over short periods can be used for planning of power distribution and enhancements on Brazil's present capacity to use this resource. The computational power available today allows the simulation of the atmospheric flow in great detail. For instance, one of the authors participated in a research that demonstrated the interaction between the lake and maritime breeze in this region through the use of a atmospheric <span class="hlt">model</span>. Therefore, we aim to evaluate simulations of wind conditions and its potential to generate energy in this region. The <span class="hlt">model</span> applied is the Weather Research and Forecasting , which is the <span class="hlt">mesoscale</span> weather forecast software. The calculation domain is centered in 32oS and 52oW, in the southern region of Rio Grande do Sul state. The initial conditions of the simulation are taken from the global weather forecast in the time period from October 1st to October 31st, 2006. The wind power potential was calculated for a generic turbine, with a blade length of 52 m, using the expression: P=1/2*d*A*Cp*v^3, where P is the wind power energy (in Watts), d is the density (equal to 1.23 kg/m^3), A is the area section, which is equal to 8500 m2 , and v is the intensity of the velocity. The evaluation was done for a turbine placed at 50 m and 150 m of height. A threshold was chosen for a turbine production of 1.5 MW to estimate the potential of the site. In contrast to northern Brazilian region, which has a rather constant wind condition, this region shows a great variation of power output due to the weather variability. During the period of the study, at least three frontal systems went over the region, and thre was a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JMEP...19...22G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JMEP...19...22G"><span id="translatedtitle">Development of a <span class="hlt">Meso-Scale</span> Material <span class="hlt">Model</span> for Ballistic Fabric and Its Use in Flexible-Armor Protection Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grujicic, M.; Bell, W. C.; Arakere, G.; He, T.; Xie, X.; Cheeseman, B. A.</p> <p>2010-02-01</p> <p>A <span class="hlt">meso-scale</span> ballistic material <span class="hlt">model</span> for a prototypical plain-woven single-ply flexible armor is developed and implemented in a material user subroutine for the use in commercial explicit finite element programs. The main intent of the <span class="hlt">model</span> is to attain computational efficiency when calculating the mechanical response of the multi-ply fabric-based flexible-armor material during its impact with various projectiles without significantly sacrificing the key physical aspects of the fabric microstructure, architecture, and behavior. To validate the new <span class="hlt">model</span>, a comparative finite element method analysis is carried out in which: (a) the plain-woven single-ply fabric is <span class="hlt">modeled</span> using conventional shell elements and weaving is done in an explicit manner by snaking the yarns through the fabric and (b) the fabric is treated as a planar continuum surface composed of conventional shell elements to which the new <span class="hlt">meso-scale</span> unit-cell based material <span class="hlt">model</span> is assigned. The results obtained show that the material <span class="hlt">model</span> provides a reasonably good description for the fabric deformation and fracture behavior under different combinations of fixed and free boundary conditions. Finally, the <span class="hlt">model</span> is used in an investigation of the ability of a multi-ply soft-body armor vest to protect the wearer from impact by a 9-mm round nose projectile. The effects of inter-ply friction, projectile/yarn friction, and the far-field boundary conditions are revealed and the results explained using simple wave mechanics principles, high-deformation rate material behavior, and the role of various energy-absorbing mechanisms in the fabric-based armor systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020020656&hterms=statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dstatistics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020020656&hterms=statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dstatistics"><span id="translatedtitle">Estimation of <span class="hlt">Mesoscale</span> Atmospheric Latent Heating Profiles from TRMM Rain Statistics Utilizing a Simple One-Dimensional <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>Iacovazzi, Robert A., Jr.; Prabhakara, C.; Lau, William K. M. (Technical Monitor)</p> <p>2001-01-01</p> <p>In this study, a <span class="hlt">model</span> is developed to estimate <span class="hlt">mesoscale</span>-resolution atmospheric latent heating (ALH) profiles. It utilizes rain statistics deduced from Tropical Rainfall Measuring Mission (TRMM) data, and cloud vertical velocity profiles and regional surface thermodynamic climatologies derived from other available data sources. From several rain events observed over tropical ocean and land, ALH profiles retrieved by this <span class="hlt">model</span> in convective rain regions reveal strong warming throughout most of the troposphere, while in stratiform rain regions they usually show slight cooling below the freezing level and significant warming above. The <span class="hlt">mesoscale</span>-average, or total, ALH profiles reveal a dominant stratiform character, because stratiform rain areas are usually much larger than convective rain areas. Sensitivity tests of the <span class="hlt">model</span> show that total ALH at a given tropospheric level varies by less than +/- 10 % when convective and stratiform rain rates and <span class="hlt">mesoscale</span> fractional rain areas are perturbed individually by 1 15 %. This is also found when the non-uniform convective vertical velocity profiles are replaced by one that is uniform. Larger variability of the total ALH profiles arises when climatological ocean- and land-surface temperatures (water vapor mixing ratios) are independently perturbed by +/- 1.0 K (+/- 5 %) and +/- 5.0 K (+/- 15 %), respectively. At a given tropospheric level, such perturbations can cause a +/- 25 % variation of total ALH over ocean, and a factor-of-two sensitivity over land. This sensitivity is reduced substantially if perturbations of surface thermodynamic variables do not change surface relative humidity, or are not extended throughout the entire <span class="hlt">model</span> evaporation layer. The ALH profiles retrieved in this study agree qualitatively with tropical total diabatic heating profiles deduced in earlier studies. Also, from January and July 1999 ALH-profile climatologies generated separately with TRMM Microwave Imager and Precipitation Radar rain</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1793c0025J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1793c0025J"><span id="translatedtitle">Extending atomistic scale chemistry to <span class="hlt">mesoscale</span> <span class="hlt">model</span> of condensed-phase deflagration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Joshi, Kaushik; Chaudhuri, Santanu</p> <p>2017-01-01</p> <p>Predictive simulations connecting chemistry that follow the shock or thermal initiation of energetic materials to subsequent deflagration or detonation events is currently outside the realm of possibilities. Molecular dynamics and first-principles based dynamics have made progress in understanding reactions in picosecond to nanosecond time scale. Results from thermal ignition of different phases of RDX show a complex reaction network and emergence of a deterministic behavior for critical temperature before ignition and hot spot growth rates. The kinetics observed is dependent on the hot spot temperature, system size and thermal conductivity. For cases where ignition is observed, the incubation period is dominated by intermolecular and intramolecular hydrogen transfer reactions. The gradual temperature and pressure increase in the incubation period is accompanied by accumulation of heavier polyradicals. The challenge of connecting such chemistry in <span class="hlt">mesoscale</span> simulations remain in reducing the complexity of chemistry. The hot spot growth kinetics in RDX grains and interfaces is an important challenge for reactive simulations aiming to fill in the gaps in our knowledge in the nanoseconds to microseconds time scale. The results discussed indicate that the <span class="hlt">mesoscale</span> chemistry may include large polyradical molecules in dense reactive mix reaching an instability point at certain temperatures and pressures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ISPAr49B2..131V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ISPAr49B2..131V"><span id="translatedtitle">The Need of <span class="hlt">Nested</span> Grids for Aerial and Satellite Images and Digital Elevation <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>Villa, G.; Mas, S.; Fernández-Villarino, X.; Martínez-Luceño, J.; Ojeda, J. C.; Pérez-Martín, B.; Tejeiro, J. A.; García-González, C.; López-Romero, E.; Soteres, C.</p> <p>2016-06-01</p> <p>Usual workflows for production, archiving, dissemination and use of Earth observation images (both aerial and from remote sensing satellites) pose big interoperability problems, as for example: non-alignment of pixels at the different levels of the pyramids that makes it impossible to overlay, compare and mosaic different orthoimages, without resampling them and the need to apply multiple resamplings and compression-decompression cycles. These problems cause great inefficiencies in production, dissemination through web services and processing in "Big Data" environments. Most of them can be avoided, or at least greatly reduced, with the use of a common "<span class="hlt">nested</span> grid" for mutiresolution production, archiving, dissemination and exploitation of orthoimagery, digital elevation <span class="hlt">models</span> and other raster data. "<span class="hlt">Nested</span> grids" are space allocation schemas that organize image footprints, pixel sizes and pixel positions at all pyramid levels, in order to achieve coherent and consistent multiresolution coverage of a whole working area. A "<span class="hlt">nested</span> grid" must be complemented by an appropriate "tiling schema", ideally based on the "quad-tree" concept. In the last years a "de facto standard" grid and Tiling Schema has emerged and has been adopted by virtually all major geospatial data providers. It has also been adopted by OGC in its "WMTS Simple Profile" standard. In this paper we explain how the adequate use of this tiling schema as common <span class="hlt">nested</span> grid for orthoimagery, DEMs and other types of raster data constitutes the most practical solution to most of the interoperability problems of these types of data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014MMI....20..733Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014MMI....20..733Z"><span id="translatedtitle"><span class="hlt">Modelling</span> of acoustic waves propagating in <span class="hlt">nesting</span> Fibonacci super-lattice phononic crystal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Min; Qi, Hai-Feng; Xu, Jia-Hui; Xie, Ya-Zhuo; Zhang, Xing-Gan; Gao, Jian</p> <p>2014-07-01</p> <p>Herein, we report construction of one kind of <span class="hlt">nesting</span>-Fibonacci-super-lattice phononic crystal, in which the super-lattice cell is a well-defined Fibonacci generation sequence. We present a comparative study on band-gap structures of acoustic waves propagating in one-dimensional, <span class="hlt">nesting</span> Fibonacci-periodic structure and simple-periodic structure. We find that there are more band gaps in <span class="hlt">nesting</span> Fibonacci super-lattice <span class="hlt">models</span>, and that they present behavior different from the split-up of band gaps with different generation numbers. With the increase of generation number, more band gaps split and occur. Additionally, when generation number becomes larger, Bragg scattering becomes more significant: the characteristic curves become flatter and band gaps become wider. Furthermore, we study the effect of various parameters such as density, thickness and defects on band-gap structures. Our work is significant both for understanding the intrinsic physical properties of <span class="hlt">nesting</span> Fibonacci sequences and for providing flexible choices to meet real engineering requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10119533','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10119533"><span id="translatedtitle">An approach for parameterizing <span class="hlt">mesoscale</span> precipitating systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Weissbluth, M.J.; Cotton, W.R.</p> <p>1991-12-31</p> <p>A cumulus parameterization laboratory has been described which uses a reference numerical <span class="hlt">model</span> to fabricate, calibrate and verify a cumulus parameterization scheme suitable for use in <span class="hlt">mesoscale</span> <span class="hlt">models</span>. Key features of this scheme include resolution independence and the ability to provide hydrometeor source functions to the host <span class="hlt">model</span>. Thus far, only convective scale drafts have been parameterized, limiting the use of the scheme to those <span class="hlt">models</span> which can resolve the <span class="hlt">mesoscale</span> circulations. As it stands, the scheme could probably be incorporated into <span class="hlt">models</span> having a grid resolution greater than 50 km with results comparable to the existing schemes for the large-scale <span class="hlt">models</span>. We propose, however, to quantify the <span class="hlt">mesoscale</span> circulations through the use of the cumulus parameterization laboratory. The inclusion of these <span class="hlt">mesoscale</span> drafts in the existing scheme will hopefully allow the correct parameterization of the organized <span class="hlt">mesoscale</span> precipitating systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5750068','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5750068"><span id="translatedtitle">An approach for parameterizing <span class="hlt">mesoscale</span> precipitating systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Weissbluth, M.J.; Cotton, W.R.</p> <p>1991-01-01</p> <p>A cumulus parameterization laboratory has been described which uses a reference numerical <span class="hlt">model</span> to fabricate, calibrate and verify a cumulus parameterization scheme suitable for use in <span class="hlt">mesoscale</span> <span class="hlt">models</span>. Key features of this scheme include resolution independence and the ability to provide hydrometeor source functions to the host <span class="hlt">model</span>. Thus far, only convective scale drafts have been parameterized, limiting the use of the scheme to those <span class="hlt">models</span> which can resolve the <span class="hlt">mesoscale</span> circulations. As it stands, the scheme could probably be incorporated into <span class="hlt">models</span> having a grid resolution greater than 50 km with results comparable to the existing schemes for the large-scale <span class="hlt">models</span>. We propose, however, to quantify the <span class="hlt">mesoscale</span> circulations through the use of the cumulus parameterization laboratory. The inclusion of these <span class="hlt">mesoscale</span> drafts in the existing scheme will hopefully allow the correct parameterization of the organized <span class="hlt">mesoscale</span> precipitating systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcMod.107...48B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcMod.107...48B"><span id="translatedtitle">Impact of operational <span class="hlt">model</span> <span class="hlt">nesting</span> approaches and inherent errors for coastal simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brown, Jennifer M.; Norman, Danielle L.; Amoudry, Laurent O.; Souza, Alejandro J.</p> <p>2016-11-01</p> <p>A region of freshwater influence (ROFI) under hypertidal conditions is used to demonstrate inherent problems for <span class="hlt">nested</span> operational <span class="hlt">modelling</span> systems. Such problems can impact the accurate simulation of freshwater export within shelf seas, so must be considered in coastal ocean <span class="hlt">modelling</span> studies. In Liverpool Bay (our UK study site), freshwater inflow from 3 large estuaries forms a coastal front that moves in response to tides and winds. The cyclic occurrence of stratification and remixing is important for the biogeochemical cycles, as nutrient and pollutant loaded freshwater is introduced into the coastal system. Validation methods, using coastal observations from fixed moorings and cruise transects, are used to assess the simulation of the ROFI, through improved spatial structure and temporal variability of the front, as guidance for best practise <span class="hlt">model</span> setup. A structured <span class="hlt">modelling</span> system using a 180 m grid <span class="hlt">nested</span> within a 1.8 km grid demonstrates how compensation for error at the coarser resolution can have an adverse impact on the <span class="hlt">nested</span>, high resolution application. Using 2008, a year of typical calm and stormy periods with variable river influence, the sensitivities of the ROFI dynamics to initial and boundary conditions are investigated. It is shown that accurate representation of the initial water column structure is important at the regional scale and that the boundary conditions are most important at the coastal scale. Although increased grid resolution captures the frontal structure, the accuracy in frontal position is determined by the offshore boundary conditions and therefore the accuracy of the coarser regional <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1714285S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1714285S"><span id="translatedtitle">Performance of MODIS satellite and <span class="hlt">mesoscale</span> <span class="hlt">model</span> based land surface temperature for soil moisture deficit estimation using Neural Network</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Srivastava, Prashant K.; Petropoulos, George P.; Gupta, Manika; Islam, Tanvir</p> <p>2015-04-01</p> <p>Soil Moisture Deficit (SMD) is a key variable in the water and energy exchanges that occur at the land-surface/atmosphere interface. Monitoring SMD is an alternate method of irrigation scheduling and represents the use of the suitable quantity of water at the proper time by combining measurements of soil moisture deficit. In past it is found that LST has a strong relation to SMD, which can be estimated by MODIS or numerical weather prediction <span class="hlt">model</span> such as WRF (Weather Research and Forecasting <span class="hlt">model</span>). By looking into the importance of SMD, this work focused on the application of Artificial Neural Network (ANN) for evaluating its capabilities towards SMD estimation using the LST data estimated from MODIS and WRF <span class="hlt">mesoscale</span> <span class="hlt">model</span>. The benchmark SMD estimated from Probability Distribution <span class="hlt">Model</span> (PDM) over the Brue catchment, Southwest of England, U.K. is used for all the calibration and validation experiments. The performances between observed and simulated SMD are assessed in terms of the Nash-Sutcliffe Efficiency (NSE), the Root Mean Square Error (RMSE) and the percentage of bias (%Bias). The application of the ANN confirmed a high capability WRF and MODIS LST for prediction of SMD. Performance during the ANN calibration and validation showed a good agreement between benchmark and estimated SMD with MODIS LST information with significantly higher performance than WRF simulated LST. The work presented showed the first comprehensive application of LST from MODIS and WRF <span class="hlt">mesoscale</span> <span class="hlt">model</span> for hydrological SMD estimation, particularly for the maritime climate. More studies in this direction are recommended to hydro-meteorological community, so that useful information will be accumulated in the technical literature domain for different geographical locations and climatic conditions. Keyword: WRF, Land Surface Temperature, MODIS satellite, Soil Moisture Deficit, Neural Network</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..416..518G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..416..518G"><span id="translatedtitle">A dual theory of price and value in a <span class="hlt">meso-scale</span> economic <span class="hlt">model</span> with stochastic profit rate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Greenblatt, R. E.</p> <p>2014-12-01</p> <p>The problem of commodity price determination in a market-based, capitalist economy has a long and contentious history. Neoclassical microeconomic theories are based typically on marginal utility assumptions, while classical macroeconomic theories tend to be value-based. In the current work, I study a simplified <span class="hlt">meso-scale</span> <span class="hlt">model</span> of a commodity capitalist economy. The production/exchange <span class="hlt">model</span> is represented by a network whose nodes are firms, workers, capitalists, and markets, and whose directed edges represent physical or monetary flows. A pair of multivariate linear equations with stochastic input parameters represent physical (supply/demand) and monetary (income/expense) balance. The input parameters yield a non-degenerate profit rate distribution across firms. Labor time and price are found to be eigenvector solutions to the respective balance equations. A simple relation is derived relating the expected value of commodity price to commodity labor content. Results of Monte Carlo simulations are consistent with the stochastic price/labor content relation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1692383','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1692383"><span id="translatedtitle">A <span class="hlt">model</span> for the emergence of pillars, walls and royal chambers in termite <span class="hlt">nests</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>Bonabeau, E.</p> <p>1998-01-01</p> <p>A simple <span class="hlt">model</span> of the emergence of pillars in termite <span class="hlt">nests</span> by Deneubourg is modified to include several additional features that break the homogeneity of the original <span class="hlt">model</span>: (i) a convection air stream that drives molecules of pheromone along a given direction; (ii) a net flux of individuals in a specific direction; (iii) a well-defined self-maintained pheromone trail; and (iv) a pheromonal template representing the effect of the presence of a queen that continuously emits pheromone. It is shown that, under certain conditions, pillars are transformed into walls or galleries or chambers, and that this transformation may not be driven by any change in the termites' behaviour. Because the same type of response at the individual level can generate different patterns under different conditions, and because previous construction modifies current building conditions, we hypothesize that <span class="hlt">nest</span> complexity can result from the unfolding of a morphogenetic process that progressively generates a diversity of history-dependent structures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.C53A0549E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.C53A0549E"><span id="translatedtitle">Toward Improved Parameterization of a <span class="hlt">Meso-Scale</span> Hydrologic <span class="hlt">Model</span> in a Discontinuous Permafrost, Boreal Forest Ecosystem</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Endalamaw, A. M.; Bolton, W. R.; Young, J. M.; Morton, D.; Hinzman, L. D.</p> <p>2013-12-01</p> <p>The sub-arctic environment can be characterized as being located in the zone of discontinuous permafrost. Although the distribution of permafrost is site specific, it dominates many of the hydrologic and ecologic responses and functions including vegetation distribution, stream flow, soil moisture, and storage processes. In this region, the boundaries that separate the major ecosystem types (deciduous dominated and coniferous dominated ecosystems) as well as permafrost (permafrost verses non-permafrost) occur over very short spatial scales. One of the goals of this research project is to improve parameterizations of <span class="hlt">meso-scale</span> hydrologic <span class="hlt">models</span> in this environment. Using the Caribou-Poker Creeks Research Watershed (CPCRW) as the test area, simulations of the headwater catchments of varying permafrost and vegetation distributions were performed. CPCRW, located approximately 50 km northeast of Fairbanks, Alaska, is located within the zone of discontinuous permafrost and the boreal forest ecosystem. The Variable Infiltration Capacity (VIC) <span class="hlt">model</span> was selected as the hydrologic <span class="hlt">model</span>. In CPCRW, permafrost and coniferous vegetation is generally found on north facing slopes and valley bottoms. Permafrost free soils and deciduous vegetation is generally found on south facing slopes. In this study, hydrologic simulations using fine scale vegetation and soil parameterizations - based upon slope and aspect analysis at a 50 meter resolution - were conducted. Simulations were also conducted using downscaled vegetation from the Scenarios Network for Alaska and Arctic Planning (SNAP) (1 km resolution) and soil data sets from the Food and Agriculture Organization (FAO) (approximately 9 km resolution). Preliminary simulation results show that soil and vegetation parameterizations based upon fine scale slope/aspect analysis increases the R2 values (0.5 to 0.65 in the high permafrost (53%) basin; 0.43 to 0.56 in the low permafrost (2%) basin) relative to parameterization based on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20010037685&hterms=Model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D70%26Ntt%3DModel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20010037685&hterms=Model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D70%26Ntt%3DModel"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Convective Systems in SCSMEX: Simulated by a Regional Climate <span class="hlt">Model</span> and a Cloud Resolving <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>Tao, W.-K.; Wang, Y.; Lau, W.; Jia, Y.; Johnson, D.; Shie, C.-L.; Einaudi, Franco (Technical Monitor)</p> <p>2001-01-01</p> <p>A Regional Land-Atmosphere Climate Simulation (RELACS) System is being developed and implemented at NASA Goddard Space Flight Center. One of the major goals of RELACS is to use a regional scale <span class="hlt">model</span> with improved physical processes, in particular land-related processes, to understand the role of the land surface and its interaction with convection and radiation as well as the water and energy cycles in Indo-China/South China Sea (SCS)/China, North America and South America. The Penn State/NCAR MM5 atmospheric <span class="hlt">modeling</span> system, a state of the art atmospheric numerical <span class="hlt">model</span> designed to simulate regional weather and climate, has been successfully coupled to the Goddard Parameterization for Land-Atmosphere-Cloud Exchange (PLACE) land surface <span class="hlt">model</span>, PLACE allows for the effect A vegetation, and thus important physical processes such as evapotranspiration and interception are included. The PLACE <span class="hlt">model</span> incorporates vegetation type and has been shown in international comparisons to accurately predict evapotranspiration and runoff over a wide variety of land surfaces. The coupling of MM5 and PLACE creates a numerical <span class="hlt">modeling</span> system with the potential to more realistically simulate the atmosphere and land surface processes including land-sea interaction, regional circulations such as monsoons, and flash flood events. RELACS has been used to simulate the onset of the South China Sea Monsoon in 1986, 1991 and 1998. Sensitivity tests on various land surface <span class="hlt">models</span>, cumulus parameterization schemes (CPSs), sea surface temperature (SST) variations and midlatitude influences have been performed. These tests have indicated that the land surface <span class="hlt">model</span> has a major impact on the circulation over the South China Sea. CPSs can effect the precipitation pattern while SST variation can effect the precipitation amounts over both land and ocean. RELACS has also been used to understand the soil-precipitation interaction and feedback associated with a flood event that occurred in and around</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('https://ntrs.nasa.gov/search.jsp?R=20020061382&hterms=Model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D70%26Ntt%3DModel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020061382&hterms=Model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D70%26Ntt%3DModel"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Convective Systems in SCSMEX: Simulated by a Regional Climate <span class="hlt">Model</span> and a Cloud Resolving <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>Tao, W.-K.; Wang, Y.; Qian, I.; Lau, W.; Shie, C.-L.; Starr, David (Technical Monitor)</p> <p>2002-01-01</p> <p>A Regional Land-Atmosphere Climate Simulation (RELACS) System is being developed and implemented at NASA Goddard Space Flight Center. One of the major goals of RELACS is to use a regional scale <span class="hlt">model</span> with improved physical processes, in particular land-related processes, to understand the role of the land surface and its interaction with convection and radiation as well as the water and energy cycles in Indo-China/ South China Sea (SCS)/China, N. America and S. America. The Penn State/NCAR MM5 atmospheric <span class="hlt">modeling</span> system, a state of the art atmospheric numerical <span class="hlt">model</span> designed to simulate regional weather and climate, has been successfully coupled to the Goddard Parameterization for Land-Atmosphere-C loud Exchange (PLACE) land surface <span class="hlt">model</span>. PLACE allows for the effects of vegetation, and thus important physical processes such as evapotranspiration and interception are included. The PLACE <span class="hlt">model</span> incorporates vegetation type and has been shown in international comparisons to accurately predict evapotranspiration and runoff over a wide variety of land surfaces. The coupling of MM5 and PLACE creates a numerical <span class="hlt">modeling</span> system with the potential to more realistically simulate the atmosphere and land surface processes including land-sea interaction, regional circulations such as monsoons, and flash flood events. RELACS has been used to simulate the onset of the South China Sea Monsoon in 1986, 1997 and 1998. Sensitivity tests on various land surface <span class="hlt">models</span>, cumulus parameterization schemes (CPSs), sea surface temperature (SST) variations and midlatitude influences have been performed. These tests have indicated that the land surface <span class="hlt">model</span> has a major impact on the circulation over the S. China Sea. CPSs can effect the precipitation pattern while SST variation can effect the precipitation amounts over both land and ocean. RELACS has also been used to understand the soil-precipitation interaction and feedback associated with a flood event that occurred in and around China</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1235292-top-down-estimate-methane-emissions-california-using-mesoscale-inverse-modeling-technique-south-coast-air-basin','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1235292-top-down-estimate-methane-emissions-california-using-mesoscale-inverse-modeling-technique-south-coast-air-basin"><span id="translatedtitle">Top-down estimate of methane emissions in California using a <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> technique: The South Coast Air Basin</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Cui, Yu Yan; Brioude, Jerome; McKeen, Stuart A.; ...</p> <p>2015-07-28</p> <p>Methane (CH4) is the primary component of natural gas and has a larger global warming potential than CO2. Some recent top-down studies based on observations showed CH4 emissions in California's South Coast Air Basin (SoCAB) were greater than those expected from population-apportioned bottom-up state inventories. In this study, we quantify CH4 emissions with an advanced <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> system at a resolution of 8 km × 8 km, using aircraft measurements in the SoCAB during the 2010 Nexus of Air Quality and Climate Change campaign to constrain the inversion. To simulate atmospheric transport, we use the FLEXible PARTicle-Weather Research andmore » Forecasting (FLEXPART-WRF) Lagrangian particle dispersion <span class="hlt">model</span> driven by three configurations of the Weather Research and Forecasting (WRF) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. We determine surface fluxes of CH4 using a Bayesian least squares method in a four-dimensional inversion. Simulated CH4 concentrations with the posterior emission inventory achieve much better correlations with the measurements (R2 = 0.7) than using the prior inventory (U.S. Environmental Protection Agency's National Emission Inventory 2005, R2 = 0.5). The emission estimates for CH4 in the posterior, 46.3 ± 9.2 Mg CH4/h, are consistent with published observation-based estimates. Changes in the spatial distribution of CH4 emissions in the SoCAB between the prior and posterior inventories are discussed. Missing or underestimated emissions from dairies, the oil/gas system, and landfills in the SoCAB seem to explain the differences between the prior and posterior inventories. Furthermore, we estimate that dairies contributed 5.9 ± 1.7 Mg CH4/h and the two sectors of oil and gas industries (production and downstream) and landfills together contributed 39.6 ± 8.1 Mg CH4/h in the SoCAB.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRD..120.6698C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRD..120.6698C"><span id="translatedtitle">Top-down estimate of methane emissions in California using a <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> technique: The South Coast Air Basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cui, Yu Yan; Brioude, Jerome; McKeen, Stuart A.; Angevine, Wayne M.; Kim, Si-Wan; Frost, Gregory J.; Ahmadov, Ravan; Peischl, Jeff; Bousserez, Nicolas; Liu, Zhen; Ryerson, Thomas B.; Wofsy, Steve C.; Santoni, Gregory W.; Kort, Eric A.; Fischer, Marc L.; Trainer, Michael</p> <p>2015-07-01</p> <p>Methane (CH4) is the primary component of natural gas and has a larger global warming potential than CO2. Recent top-down studies based on observations showed CH4 emissions in California's South Coast Air Basin (SoCAB) were greater than those expected from population-apportioned bottom-up state inventories. In this study, we quantify CH4 emissions with an advanced <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> system at a resolution of 8 km × 8 km, using aircraft measurements in the SoCAB during the 2010 Nexus of Air Quality and Climate Change campaign to constrain the inversion. To simulate atmospheric transport, we use the FLEXible PARTicle-Weather Research and Forecasting (FLEXPART-WRF) Lagrangian particle dispersion <span class="hlt">model</span> driven by three configurations of the Weather Research and Forecasting (WRF) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. We determine surface fluxes of CH4 using a Bayesian least squares method in a four-dimensional inversion. Simulated CH4 concentrations with the posterior emission inventory achieve much better correlations with the measurements (R2 = 0.7) than using the prior inventory (U.S. Environmental Protection Agency's National Emission Inventory 2005, R2 = 0.5). The emission estimates for CH4 in the posterior, 46.3 ± 9.2 Mg CH4/h, are consistent with published observation-based estimates. Changes in the spatial distribution of CH4 emissions in the SoCAB between the prior and posterior inventories are discussed. Missing or underestimated emissions from dairies, the oil/gas system, and landfills in the SoCAB seem to explain the differences between the prior and posterior inventories. We estimate that dairies contributed 5.9 ± 1.7 Mg CH4/h and the two sectors of oil and gas industries (production and downstream) and landfills together contributed 39.6 ± 8.1 Mg CH4/h in the SoCAB.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.A12D..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.A12D..05S"><span id="translatedtitle">Hurricane <span class="hlt">Modeling</span> and Supercomputing: Can a global <span class="hlt">mesoscale</span> <span class="hlt">model</span> be useful in improving forecasts of tropical cyclogenesis?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, B.; Tao, W.; Atlas, R.</p> <p>2007-12-01</p> <p>Hurricane <span class="hlt">modeling</span>, along with guidance from observations, has been used to help construct hurricane theories since the 1960s. CISK (conditional instability of the second kind, Charney and Eliassen 1964; Ooyama 1964,1969) and WISHE (wind-induced surface heat exchange, Emanuel 1986) are among the well-known theories being used to understand hurricane intensification. For hurricane genesis, observations have indicated the importance of large-scale flows (e.g., the Madden-Julian Oscillation or MJO, Maloney and Hartmann, 2000) on the modulation of hurricane activity. Recent <span class="hlt">modeling</span> studies have focused on the role of the MJO and Rossby waves (e.g., Ferreira and Schubert, 1996; Aivyer and Molinari, 2003) and/or the interaction of small-scale vortices (e.g., Holland 1995; Simpson et al. 1997; Hendrick et al. 2004), of which determinism could be also built by large-scale flows. The aforementioned studies suggest a unified view on hurricane formation, consisting of multiscale processes such as scale transition (e.g., from the MJO to Equatorial Rossby Waves and from waves to vortices), and scale interactions among vortices, convection, and surface heat and moisture fluxes. To depict the processes in the unified view, a high-resolution global <span class="hlt">model</span> is needed. During the past several years, supercomputers have enabled the deployment of ultra-high resolution global <span class="hlt">models</span>, obtaining remarkable forecasts of hurricane track and intensity (Atlas et al. 2005; Shen et al. 2006). In this work, hurricane genesis is investigated with the aid of a global <span class="hlt">mesoscale</span> <span class="hlt">model</span> on the NASA Columbia supercomputer by conducting numerical experiments on the genesis of six consecutive tropical cyclones (TCs) in May 2002. These TCs include two pairs of twin TCs in the Indian Ocean, Supertyphoon Hagibis in the West Pacific Ocean and Hurricane Alma in the East Pacific Ocean. It is found that the <span class="hlt">model</span> is capable of predicting the genesis of five of these TCs about two to three days in advance. Our</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25854648','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25854648"><span id="translatedtitle">Using cumulative sums of martingale residuals for <span class="hlt">model</span> checking in <span class="hlt">nested</span> case-control studies.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Borgan, Ørnulf; Zhang, Ying</p> <p>2015-09-01</p> <p>Standard use of Cox regression requires collection of covariate information for all individuals in a cohort even when only a small fraction of them experiences the event of interest (fail). This may be very expensive for large cohorts. Further in biomarker studies, it will imply a waste of valuable biological material that one may want to save for future studies. A <span class="hlt">nested</span> case-control study offers a useful alternative. For this design, covariate information is only needed for the failing individuals (cases) and a sample of controls selected from the cases' at-risk sets. Methods based on martingale residuals are useful for checking the fit of Cox's regression <span class="hlt">model</span> for cohort data. But similar methods have so far not been developed for <span class="hlt">nested</span> case-control data. In this article, it is described how one may define martingale residuals for <span class="hlt">nested</span> case-control data, and it is shown how plots and tests based on cumulative sums of martingale residuals may be used to check <span class="hlt">model</span> fit. The plots and tests may be obtained using available software.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4006220','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4006220"><span id="translatedtitle">Applications of a Kullback-Leibler Divergence for Comparing Non-<span class="hlt">nested</span> <span class="hlt">Models</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>Wang, Chen-Pin; Jo, Booil</p> <p>2014-01-01</p> <p>Wang and Ghosh (2011) proposed a Kullback-Leibler divergence (KLD) which is asymptotically equivalent to the KLD by Goutis and Robert (1998) when the reference <span class="hlt">model</span> (in comparison with a competing fitted <span class="hlt">model</span>) is correctly specified and when certain regularity conditions hold true. While properties of the KLD by Wang and Ghosh (2011) have been investigated in the Bayesian framework, this paper further explores the property of this KLD in the frequentist framework using four application examples, each fitted by two competing non-<span class="hlt">nested</span> <span class="hlt">models</span>. PMID:24795532</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GMD.....9.4439G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GMD.....9.4439G"><span id="translatedtitle">Advantages of using a fast urban boundary layer <span class="hlt">model</span> as compared to a full <span class="hlt">mesoscale</span> <span class="hlt">model</span> to simulate the urban heat island of Barcelona</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>García-Díez, Markel; Lauwaet, Dirk; Hooyberghs, Hans; Ballester, Joan; De Ridder, Koen; Rodó, Xavier</p> <p>2016-12-01</p> <p>As most of the population lives in urban environments, the simulation of the urban climate has become a key problem in the framework of the climate change impact assessment. However, the high computational power required by high-resolution (sub-kilometre) fully coupled land-atmosphere simulations using urban canopy parameterisations is a severe limitation. Here we present a study on the performance of UrbClim, an urban boundary layer <span class="hlt">model</span> designed to be several orders of magnitude faster than a full-fledged <span class="hlt">mesoscale</span> <span class="hlt">model</span>. The simulations are evaluated with station data and land surface temperature observations from satellites, focusing on the urban heat island (UHI). To explore the advantages of using a simple <span class="hlt">model</span> like UrbClim, the results are compared with a simulation carried out with a state-of-the-art <span class="hlt">mesoscale</span> <span class="hlt">model</span>, the Weather Research and Forecasting <span class="hlt">Model</span>, which includes an urban canopy <span class="hlt">model</span>. This comparison is performed with driving data from ERA-Interim reanalysis (70 km). In addition, the effect of using driving data from a higher-resolution forecast <span class="hlt">model</span> (15 km) is explored in the case of UrbClim. The results show that the performance of reproducing the average UHI in the simple <span class="hlt">model</span> is generally comparable to the one in the <span class="hlt">mesoscale</span> <span class="hlt">model</span> when driven with reanalysis data (70 km). However, the simple <span class="hlt">model</span> needs higher-resolution data from the forecast <span class="hlt">model</span> (15 km) to correctly reproduce the variability of the UHI at a daily scale, which is related to the wind speed. This lack of accuracy in reproducing the wind speed, especially the sea-breeze daily cycle, which is strong in Barcelona, also causes a warm bias in the reanalysis driven UrbClim run. We conclude that medium-complexity <span class="hlt">models</span> as UrbClim are a suitable tool to simulate the urban climate, but that they are sensitive to the ability of the input data to represent the local wind regime. UrbClim is a well suited <span class="hlt">model</span> for impact and adaptation studies at city scale without high</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5899806','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5899806"><span id="translatedtitle">MELSAR: a <span class="hlt">mesoscale</span> air quality <span class="hlt">model</span> for complex terrain. Volume 1. Overview, technical description and user's guide</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Allwine, K.J.; Whiteman, C.D.</p> <p>1985-04-01</p> <p>This final report is submitted as part of the Green River Ambient <span class="hlt">Model</span> Assessment (GRAMA) program conducted at the US Department of Energy's Pacific Northwest Laboratory for the US Environmental Protection Agency. The GRAMA program has, as its ultimate goal, the development of validated air quality <span class="hlt">models</span> that can be applied to the complex terrain of the Green River Formation of western Colorado, eastern Utah, and southern Wyoming. The Green River Formation is a geologic formation containing large reserves of oil shale, coal, and other natural resources. Development of these resources may lead to a degradation of the air quality of the region. Air quality <span class="hlt">models</span> are needed immediately for planning and regulatory purposes to assess the magnitude of these regional impacts. This report documents one of the <span class="hlt">models</span> being developed for this purpose within GRAMA - specifically a <span class="hlt">model</span> to predict short averaging time (less than or equal to 24 h) pollutant concentrations resulting from the <span class="hlt">mesoscale</span> transport of pollutant releases from multiple sources. MELSAR has not undergone any rigorous operational testing, sensitivity analyses, or validation studies. Testing and evaluation of the <span class="hlt">model</span> are needed to gain a measure of confidence in the <span class="hlt">model</span>'s performance. This report consists of two volumes. Volume 1 contains the <span class="hlt">model</span> overview, technical description, and user's guide, and Volume 2 contains the Appendices which include listings of the FORTRAN code. 51 refs., 31 figs., 35 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS42A..05K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS42A..05K"><span id="translatedtitle">Potential utility of three-dimensional temperature and salinity fields estimated from satellite altimetry and Argo data for improving <span class="hlt">mesoscale</span> reproducibility in regional ocean <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>Kanki, R.; Uchiyama, Y.; Miyazaki, D.; Takano, A.; Miyazawa, Y.; Yamazaki, H.</p> <p>2014-12-01</p> <p><span class="hlt">Mesoscale</span> oceanic structure and variability are required to be reproduced as accurately as possible in realistic regional ocean <span class="hlt">modeling</span>. Uchiyama et al. (2012) demonstrated with a submesoscale eddy-resolving JCOPE2-ROMS downscaling oceanic <span class="hlt">modeling</span> system that the <span class="hlt">mesoscale</span> reproducibility of the Kuroshio meandering along Japan is significantly improved by introducing a simple restoration to data which we call "TS nudging" (a.k.a. robust diagnosis) where the prognostic temperature and salinity fields are weakly nudged four-dimensionally towards the assimilative JCOPE2 reanalysis (Miyazawa et al., 2009). However, there is not always a reliable reanalysis for oceanic downscaling in an arbitrary region and at an arbitrary time, and therefore alternative dataset should be prepared. Takano et al. (2009) proposed an empirical method to estimate <span class="hlt">mesoscale</span> 3-D thermal structure from the near real-time AVISO altimetry data along with the ARGO float data based on the two-layer <span class="hlt">model</span> of Goni et al. (1996). In the present study, we consider the TS data derived from this method as a candidate. We thus conduct a synoptic forward <span class="hlt">modeling</span> of the Kuroshio using the JCOPE2-ROMS downscaling system to explore potential utility of this empirical TS dataset (hereinafter TUM-TS) by carrying out two runs with the T-S nudging towards 1) the JCOPE2-TS and 2) TUM-TS fields. An example of the comparison between the two ROMS test runs is shown in the attached figure showing the annually averaged surface EKE. Both of TUM-TS and JCOPE2-TS are found to help reproducing the <span class="hlt">mesoscale</span> variance of the Koroshio and its extension as well as its mean paths, surface KE and EKE reasonably well. Therefore, the AVISO-ARGO derived empirical 3-D TS estimation is potentially exploitable for the dataset to conduct the T-S nudging to reproduce <span class="hlt">mesoscale</span> oceanic structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUSM.H22A..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUSM.H22A..01M"><span id="translatedtitle">Initialization of a Numerical <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> with ALEXI-derived Volumetric Soil Moisture: Case Results and Validation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mecikalski, J. R.; Hain, C. R.; Anderson, M. C.</p> <p>2006-05-01</p> <p>Soil moisture plays a vital role in the portioning of sensible and latent heat fluxes in the surface energy budget, although high spatial-resolution observations of it are quite rare. The ALEXI <span class="hlt">model</span> contains the two-source land-surface representation of Norman et al. (1995), which partitions surface fluxes and radiometric temperature into canopy and soil contributions based on the fraction of vegetation cover within the scene. Anderson et al. (1997) and Mecikalski (1999) detail the implementation of ALEXI as a regional-scale application over the continental United States. This <span class="hlt">model</span> relies on remote sensing data to operate, including GOES-derived surface brightness temperature changes, AVHRR-derived land cover properties, as well as synoptic weather data to operate (Mecikalski, 1999). This version of the ALEXI algorithm has been run daily on a 10 km resolution grid from the years 2002 to present. ALEXI diagnoses a fraction of potential evapotranspiration (fPET) for both the surface layer (0-5 cm) and root-zone (5-200 cm), given a calculation of the potential ET for each pixel. In current <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> the fraction of potential ET can be directly related to a fraction of available water, which in turn can be used to calculate volumetric soil moisture for a given soil texture. Soil moisture conditions of the surface and root-zone yield a distinctive thermal signature, where moisture deficiency will lead to surfaces warming more quickly. Current land-surface <span class="hlt">models</span> (LDAS, NLDAS) such as those used in the North American <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> (NAM) use antecedent precipitation as the primary component to the calculation of volumetric soil moisture. These <span class="hlt">models</span> use four layers in their soil <span class="hlt">model</span> (0-10, 10-40, 40-100, and 100-200 cm), while ALEXI provides derived volumetric soil moisture for only two layers within the 0-200 cm depth. This discrepancy can be solved with a blending of the two layers from ALEXI to provide a reasonable representation of the observed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100036464','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100036464"><span id="translatedtitle">An Objective Verification of the North American <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> for Kennedy Space Center and Cape Canaveral Air Force Station</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauman, William H., III</p> <p>2010-01-01</p> <p>The 45th Weather Squadron (45 WS) Launch Weather Officers (LWO's) use the 12-km resolution North American <span class="hlt">Mesoscale</span> (NAM) <span class="hlt">model</span> (MesoNAM) text and graphical product forecasts extensively to support launch weather operations. However, the actual performance of the <span class="hlt">model</span> at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) has not been measured objectively. In order to have tangible evidence of <span class="hlt">model</span> performance, the 45 WS tasked the Applied Meteorology Unit (AMU; Bauman et ai, 2004) to conduct a detailed statistical analysis of <span class="hlt">model</span> output compared to observed values. The <span class="hlt">model</span> products are provided to the 45 WS by ACTA, Inc. and include hourly forecasts from 0 to 84 hours based on <span class="hlt">model</span> initialization times of 00, 06, 12 and 18 UTC. The objective analysis compared the MesoNAM forecast winds, temperature (T) and dew pOint (T d), as well as the changes in these parameters over time, to the observed values from the sensors in the KSC/CCAFS wind tower network shown in Table 1. These objective statistics give the forecasters knowledge of the <span class="hlt">model</span>'s strengths and weaknesses, which will result in improved forecasts for operations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130012521','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130012521"><span id="translatedtitle">An Objective Verification of the North American <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> for Kennedy Space Center and Cape Canaveral Air Force Station</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bauman, William H., III</p> <p>2010-01-01</p> <p>The 45th Weather Squadron (45 WS) Launch Weather Officers use the 12-km resolution North American <span class="hlt">Mesoscale</span> (NAM) <span class="hlt">model</span> (MesoNAM) text and graphical product forecasts extensively to support launch weather operations. However, the actual performance of the <span class="hlt">model</span> at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS) has not been measured objectively. In order to have tangible evidence of <span class="hlt">model</span> performance, the 45 WS tasked the Applied Meteorology Unit to conduct a detailed statistical analysis of <span class="hlt">model</span> output compared to observed values. The <span class="hlt">model</span> products are provided to the 45 WS by ACTA, Inc. and include hourly forecasts from 0 to 84 hours based on <span class="hlt">model</span> initialization times of 00, 06, 12 and 18 UTC. The objective analysis compared the MesoNAM forecast winds, temperature and dew point, as well as the changes in these parameters over time, to the observed values from the sensors in the KSC/CCAFS wind tower network. Objective statistics will give the forecasters knowledge of the <span class="hlt">model</span>'s strength and weaknesses, which will result in improved forecasts for operations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009CSR....29..407A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009CSR....29..407A"><span id="translatedtitle"><span class="hlt">Mesoscale</span> slope current variability in the Gulf of Lions. Interpretation of in-situ measurements using a three-dimensional <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>André, Gaël; Garreau, Pierre; Fraunie, Philippe</p> <p>2009-02-01</p> <p>The ECOLOPHY experiments aimed at investigating physical exchanges between coastal and open sea. They were carried out in June and December 2005 over the shelf-break in the North-eastern part of the Gulf of Lions (Northwestern Mediterranean Sea). This area is considered to be the generation zone for the eddy and meandering structures of the Northern Current (NC). The objective of the present work is to examine <span class="hlt">mesoscale</span> variability of this coastal slope current in the light of available data. Numerical <span class="hlt">modeling</span> is used to support the field data analysis. ADCP current measurements over a one-year period show that <span class="hlt">mesoscale</span> activity is maximal in late winter, correlating with the seasonal variability of the NC and, also, partly with local winds. Measured currents exhibit <span class="hlt">mesoscale</span> fluctuations with periods ranging from 3 to 30 days, in agreement with previous analyses. Fluctuations of periods longer than 10 days are found to be mainly oriented in the direction of the mean current, whereas more frequently observed high frequency fluctuations tend to be oriented cross-slope, suggesting a relationship with the NC <span class="hlt">mesoscale</span> meandering. Moreover, trajectories of surdrift buoys launched in the NC vein exhibit <span class="hlt">mesoscale</span> phenomena, such as current meanders or eddies and on-shelf intrusions. Numerical <span class="hlt">modeling</span> provides a synoptic point of view and is used hereafter to support physical interpretation of punctual eulerian or lagrangian measurements. Therefore, <span class="hlt">modeled</span> hydrodynamic fields are used to analyze surdrift buoy trajectories and computed vertically averaged current and Ertel potential vorticity provide a better understanding of these behaviors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800009377','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800009377"><span id="translatedtitle">Development of a severe local storm prediction system: A 60-day test of a <span class="hlt">mesoscale</span> primitive equation <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>Paine, D. A.; Zack, J. W.; Kaplan, M. L.</p> <p>1979-01-01</p> <p>The progress and problems associated with the dynamical forecast system which was developed to predict severe storms are examined. The meteorological problem of severe convective storm forecasting is reviewed. The cascade hypothesis which forms the theoretical core of the <span class="hlt">nested</span> grid dynamical numerical <span class="hlt">modelling</span> system is described. The dynamical and numerical structure of the <span class="hlt">model</span> used during the 1978 test period is presented and a preliminary description of a proposed multigrid system for future experiments and tests is provided. Six cases from the spring of 1978 are discussed to illustrate the <span class="hlt">model</span>'s performance and its problems. Potential solutions to the problems are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/85417','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/85417"><span id="translatedtitle">A <span class="hlt">nested</span> <span class="hlt">model</span> study of the Sahelian climate response to sea-surface temperature anomalies</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Semazzi, F.H. M.; Lin, N.; Lin, Y.; Giorgi, F.</p> <p>1993-12-01</p> <p>A <span class="hlt">nested</span> high resolution atmospheric <span class="hlt">model</span> is used to investigate the sensitivity of the Sahelian climate to large-scale sea-surface temperature (SST) anomalies. The <span class="hlt">nested</span> system has realistic vegetation and detailed bottom orography. Two separate sets of northern hemispheric summer (June, July and August) numerical integrations are performed; one corresponding to the SST anomalies in 1950 when the Sahelian region was relatively much wetter than the long-term average conditions and a second integration based on 1984 SST anomalies when one of the driest rain seasons in the last few decades was experienced. Although the low resolution (R15 approximately equal 4.5 deg by 7.5 deg latitude by longitude) stand-alone global climate <span class="hlt">model</span> reasonably simulates the lower rainfall amounts in 1984 compared to 1950, the <span class="hlt">nested</span> system yields more realistic regional climate because its forcing includes more detailed effects of topography, land-sea contrasts, and land surface processes. In particular, two distinct rainfall maxima primarily anchored to the regions of highest terrain are simulated by the <span class="hlt">model</span>. One corresponding to the highlands in Cameroon over the Adamawa Plateau and a second maxima over Guinea and Sierra-Leone. Inspection of <span class="hlt">model</span> circulation indicates that the weaker moist cross-equatorial monsoon flow in the 1984 is responsible for the lower amounts of the Sahelian rainfall compared to 1950. Our results are in agreement with several diagnostic and <span class="hlt">modeling</span> studies performed in the recent years which show that deficient sub-Saharan rainy seasons tends to coincide with the southwesterly surface monsoon flow not extending as far north along the West African coast as in the wetter years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3735395','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3735395"><span id="translatedtitle"><span class="hlt">Nested</span> sampling for parameter inference in systems biology: application to an exemplar circadian <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></p> <p>2013-01-01</p> <p>Background <span class="hlt">Model</span> selection and parameter inference are complex problems that have yet to be fully addressed in systems biology. In contrast with parameter optimisation, parameter inference computes both the parameter means and their standard deviations (or full posterior distributions), thus yielding important information on the extent to which the data and the <span class="hlt">model</span> topology constrain the inferred parameter values. Results We report on the application of <span class="hlt">nested</span> sampling, a statistical approach to computing the Bayesian evidence Z, to the inference of parameters, and the estimation of log Z in an established <span class="hlt">model</span> of circadian rhythms. A ten-fold difference in the coefficient of variation between degradation and transcription parameters is demonstrated. We further show that the uncertainty remaining in the parameter values is reduced by the analysis of increasing numbers of circadian cycles of data, up to 4 cycles, but is unaffected by sampling the data more frequently. Novel algorithms for calculating the likelihood of a <span class="hlt">model</span>, and a characterisation of the performance of the <span class="hlt">nested</span> sampling algorithm are also reported. The methods we develop considerably improve the computational efficiency of the likelihood calculation, and of the exploratory step within <span class="hlt">nested</span> sampling. Conclusions We have demonstrated in an exemplar circadian <span class="hlt">model</span> that the estimates of posterior parameter densities (as summarised by parameter means and standard deviations) are influenced predominately by the length of the time series, becoming more narrowly constrained as the number of circadian cycles considered increases. We have also shown the utility of the coefficient of variation for discriminating between highly-constrained and less-well constrained parameters. PMID:23899119</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020020657&hterms=Major+depression&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMajor%2Bdepression','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020020657&hterms=Major+depression&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMajor%2Bdepression"><span id="translatedtitle">Combining New Satellite Tools and <span class="hlt">Models</span> to Examine Role of <span class="hlt">Mesoscale</span> Interactions in Formation and Intensification of Tropical Cyclones</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Simpson, Joanne; Pierce, H.; Ritchie, L.; Liu, T.; Brueske, K.; Velden, C.; Halverson, J.; Einaudi, Franco (Technical Monitor)</p> <p>2001-01-01</p> <p>The objective of this research is to start filling the <span class="hlt">mesoscale</span> gap to improve understanding and probability forecasts of formation and intensity variations of tropical cyclones. Sampling by aircraft equipped to measure <span class="hlt">mesoscale</span> processes is expensive, thus confined in place and time. Hence we turn to satellite products. This paper reports preliminary results of a tropical cyclone genesis and early intensification study. We explore the role of <span class="hlt">mesoscale</span> processes using a combination of products from TRMM, QuikSCAT, AMSU, also SSM/I, geosynchronous and <span class="hlt">model</span> output. Major emphasis is on the role of merging <span class="hlt">mesoscale</span> vortices. These initially form in midlevel stratiform cloud. When they form in regions of lowered Rossby radius of deformation (strong background vorticity) the <span class="hlt">mesoscale</span> vortices can last long enough to interact and merge, with the weaker vortex losing vorticity to the stronger, which can then extend down to the surface. In an earlier cyclongenesis case (Oliver 1993) off Australia, intense deep convection occurred when the stronger vortex reached the surface; this vortex became the storm center while the weaker vortex was sheared out as the major rainband. In our study of Atlantic tropical cyclones originating from African waves, we use QuikSCAT to examine surface winds in the African monsoon trough and in the vortices which move westward off the coast, which may or may not undergo genesis (defined by NHC as reaching TD, or tropical depression, with a west wind to the south of the surface low). We use AMSU mainly to examine development of warm cores. TRMM passive microwave TMI is used with SSM/I to look at the rain structure, which often indicates eye formation, and to look at the ice scattering signatures of deep convection. The TRMM precipitation radar, PR, when available, gives precipitation cross sections. So far we have detailed studies of two African-origin cyclones, one which became severe hurricane Floyd 1999, and the other reached TD2 in June</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.P51B3938P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.P51B3938P"><span id="translatedtitle">Interpretation of the Meteorological Gale Environment through Mars Science Laboratory (MSL) Rover Environmental Monitoring Station (REMS) Observations and <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> (MRAMS)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pla-García, J.; Rafkin, S. C.; Gómez-Elvira, J.; Martín-Torres, J.; Zorzano, M. P.</p> <p>2014-12-01</p> <p>Gale Crater, in which the Mars Science Laboratory (MSL) landed in August 2012, is the most topographically complex area visited to date on Mars. The meteorology within the crater may also be one of the most dynamically complex meteorological environments, because topography is thought to strongly drive the near-surface atmospheric circulations. The Rover Environmental Monitoring Station (REMS) on the Curiosity rover consists of a suite of meteorological instruments that measure pressure, temperature (air and ground), wind (speed and direction), relative humidity, and the UV flux. REMS has provided some clues on the nature of the local meteorology strongly influenced by the complex topography, as predicted by numerous previous studies. As with all single station measurements, the meteorological interpretation is typically hindered by a lack of spatial context in which to place the observations. Numerical <span class="hlt">modeling</span> results, when properly validated against observations, can provide interpretive context. In an effort to better understand the atmospheric circulations of the Gale Crater, the Mars Regional Atmospheric <span class="hlt">Modeling</span> System (MRAMS) was applied to the landing site region using <span class="hlt">nested</span> grids with a spacing of 330 meters on the innermost grid that is centered over the landing site. MRAMS is ideally suited for this investigation; the <span class="hlt">model</span> is explicitly designed to simulate Mars' atmospheric circulations at the <span class="hlt">mesoscale</span> and smaller with realistic, high resolution surface properties. Simulations with MRAMS indicate thermal and wind thermal signatures associated with slope flows, katabatic winds, and nocturnal mixing events that are consistent with the rover environment monitored by REMS. Of particular note is evidence for two distinct air masses—one in the bottom of the crater (a relatively cold potential temperature air mass) and one on the plateau—that have minimal interaction with one another. If there are indeed two distinct air masses, there are strong</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3860902','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3860902"><span id="translatedtitle">Structural <span class="hlt">Nested</span> Cumulative Failure Time <span class="hlt">Models</span> to Estimate the Effects of Interventions</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Picciotto, Sally; Hernán, Miguel A.; Page, John H.; Young, Jessica G.; Robins, James M.</p> <p>2013-01-01</p> <p>In the presence of time-varying confounders affected by prior treatment, standard statistical methods for failure time analysis may be biased. Methods that correctly adjust for this type of covariate include the parametric g-formula, inverse probability weighted estimation of marginal structural Cox proportional hazards <span class="hlt">models</span>, and g-estimation of structural <span class="hlt">nested</span> accelerated failure time <span class="hlt">models</span>. In this article, we propose a novel method to estimate the causal effect of a time-dependent treatment on failure in the presence of informative right-censoring and time-dependent confounders that may be affected by past treatment: g-estimation of structural <span class="hlt">nested</span> cumulative failure time <span class="hlt">models</span> (SNCFTMs). An SNCFTM considers the conditional effect of a final treatment at time m on the outcome at each later time k by <span class="hlt">modeling</span> the ratio of two counterfactual cumulative risks at time k under treatment regimes that differ only at time m. Inverse probability weights are used to adjust for informative censoring. We also present a procedure that, under certain “no-interaction” conditions, uses the g-estimates of the <span class="hlt">model</span> parameters to calculate unconditional cumulative risks under nondynamic (static) treatment regimes. The procedure is illustrated with an example using data from a longitudinal cohort study, in which the “treatments” are healthy behaviors and the outcome is coronary heart disease. PMID:24347749</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26ES...48a2007P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26ES...48a2007P"><span id="translatedtitle"><span class="hlt">Mesoscale</span> high-resolution <span class="hlt">modeling</span> of extreme wind speeds over western water areas of the Russian Arctic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Platonov, Vladimir S.; Kislov, Alexander V.</p> <p>2016-11-01</p> <p>A statistical analysis of extreme weather events over coastal areas of the Russian Arctic based on observational data has revealed many interesting features of wind velocity distributions. It has been shown that the extremes contain data belonging to two different statistical populations. Each of them is reliably described by a Weibull distribution. According to the standard terminology, these sets of extremes are named ‘black swans’ and ‘dragons’. The ‘dragons’ are responsible for most extremes, surpassing the ‘black swans’ by 10 - 30 %. Since the data of the global climate <span class="hlt">model</span> INM-CM4 do not contain ‘dragons’, the wind speed extremes are investigated on the <span class="hlt">mesoscale</span> using the COSMO-CLM <span class="hlt">model</span>. The <span class="hlt">modelling</span> results reveal no differences between the ‘swans’ and ‘dragons’ situations. It could be associated with the poor sample data used. However, according to many case studies and <span class="hlt">modeling</span> results we assume that it is caused by a rare superposition of large-scale synoptic factors and many local meso- and microscale factors (surface, coastline configuration, etc.). Further studies of extreme wind speeds in the Arctic, such as ‘black swans’ and ‘dragons’, are necessary to focus on non-hydrostatic high-resolution atmospheric <span class="hlt">modelling</span> using downscaling techniques.</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://adsabs.harvard.edu/abs/2016PIAHS.373..179K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PIAHS.373..179K"><span id="translatedtitle">Up-scaling of multi-variable flood loss <span class="hlt">models</span> from objects to land use units at the <span class="hlt">meso-scale</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kreibich, Heidi; Schröter, Kai; Merz, Bruno</p> <p>2016-05-01</p> <p>Flood risk management increasingly relies on risk analyses, including loss <span class="hlt">modelling</span>. Most of the flood loss <span class="hlt">models</span> usually applied in standard practice have in common that complex damaging processes are described by simple approaches like stage-damage functions. Novel multi-variable <span class="hlt">models</span> significantly improve loss estimation on the micro-scale and may also be advantageous for large-scale applications. However, more input parameters also reveal additional uncertainty, even more in upscaling procedures for <span class="hlt">meso-scale</span> applications, where the parameters need to be estimated on a regional area-wide basis. To gain more knowledge about challenges associated with the up-scaling of multi-variable flood loss <span class="hlt">models</span> the following approach is applied: Single- and multi-variable micro-scale flood loss <span class="hlt">models</span> are up-scaled and applied on the <span class="hlt">meso-scale</span>, namely on basis of ATKIS land-use units. Application and validation is undertaken in 19 municipalities, which were affected during the 2002 flood by the River Mulde in Saxony, Germany by comparison to official loss data provided by the Saxon Relief Bank (SAB).In the <span class="hlt">meso-scale</span> case study based <span class="hlt">model</span> validation, most multi-variable <span class="hlt">models</span> show smaller errors than the uni-variable stage-damage functions. The results show the suitability of the up-scaling approach, and, in accordance with micro-scale validation studies, that multi-variable <span class="hlt">models</span> are an improvement in flood loss <span class="hlt">modelling</span> also on the <span class="hlt">meso-scale</span>. However, uncertainties remain high, stressing the importance of uncertainty quantification. Thus, the development of probabilistic loss <span class="hlt">models</span>, like BT-FLEMO used in this study, which inherently provide uncertainty information are the way forward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Nests&pg=3&id=EJ679891','ERIC'); return false;" href="http://eric.ed.gov/?q=Nests&pg=3&id=EJ679891"><span id="translatedtitle"><span class="hlt">Nesting</span> Instincts.</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>Greenman, Geri</p> <p>2003-01-01</p> <p>Describes an art project where beginning drawing students used values and chiaroscuro techniques to draw bird <span class="hlt">nests</span>. Explains how the students observed the <span class="hlt">nest</span> that was displayed in the art classroom. Discusses the steps involved in creating the artworks. (CMK)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ACP....16.8983C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ACP....16.8983C"><span id="translatedtitle">Boundary-layer turbulent processes and <span class="hlt">mesoscale</span> variability represented by numerical weather prediction <span class="hlt">models</span> during the BLLAST campaign</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Couvreux, Fleur; Bazile, Eric; Canut, Guylaine; Seity, Yann; Lothon, Marie; Lohou, Fabienne; Guichard, Françoise; Nilsson, Erik</p> <p>2016-07-01</p> <p>This study evaluates the ability of three operational <span class="hlt">models</span>, with resolution varying from 2.5 to 16 km, to predict the boundary-layer turbulent processes and <span class="hlt">mesoscale</span> variability observed during the Boundary Layer Late-Afternoon and Sunset Turbulence (BLLAST) field campaign. We analyse the representation of the vertical profiles of temperature and humidity and the time evolution of near-surface atmospheric variables and the radiative and turbulent fluxes over a total of 12 intensive observing periods (IOPs), each lasting 24 h. Special attention is paid to the evolution of the turbulent kinetic energy (TKE), which was sampled by a combination of independent instruments. For the first time, this variable, a central one in the turbulence scheme used in AROME and ARPEGE, is evaluated with observations.In general, the 24 h forecasts succeed in reproducing the variability from one day to another in terms of cloud cover, temperature and boundary-layer depth. However, they exhibit some systematic biases, in particular a cold bias within the daytime boundary layer for all <span class="hlt">models</span>. An overestimation of the sensible heat flux is noted for two points in ARPEGE and is found to be partly related to an inaccurate simplification of surface characteristics. AROME shows a moist bias within the daytime boundary layer, which is consistent with overestimated latent heat fluxes. ECMWF presents a dry bias at 2 m above the surface and also overestimates the sensible heat flux. The high-resolution <span class="hlt">model</span> AROME resolves the vertical structures better, in particular the strong daytime inversion and the thin evening stable boundary layer. This <span class="hlt">model</span> is also able to capture some specific observed features, such as the orographically driven subsidence and a well-defined maximum that arises during the evening of the water vapour mixing ratio in the upper part of the residual layer due to fine-scale advection. The <span class="hlt">model</span> reproduces the order of magnitude of spatial variability observed at</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4670219','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4670219"><span id="translatedtitle">Time to Integrate to <span class="hlt">Nest</span> Test Evaluation in a Mouse DSS-Colitis <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>Häger, Christine; Keubler, Lydia M.; Biernot, Svenja; Dietrich, Jana; Buchheister, Stephanie; Buettner, Manuela; Bleich, André</p> <p>2015-01-01</p> <p>Severity assessment in laboratory animals is an important issue regarding the implementation of the 3R concept into biomedical research and pivotal in current EU regulations. In mouse <span class="hlt">models</span> of inflammatory bowel disease severity assessment is usually undertaken by clinical scoring, especially by monitoring reduction of body weight. This requires daily observance and handling of each mouse, which is time consuming, stressful for the animal and necessitates an experienced observer. The time to integrate to <span class="hlt">nest</span> test (TINT) is an easily applicable test detecting disturbed welfare by measuring the time interval mice need to integrate <span class="hlt">nesting</span> material to an existing <span class="hlt">nest</span>. Here, TINT was utilized to assess severity in a mouse DSS-colitis <span class="hlt">model</span>. TINT results depended on the group size of mice maintained per cage with most consistent time intervals measured when co-housing 4 to 5 mice. Colitis was induced with 1% or 1.5% DSS in group-housed WT and Cd14-deficient mice. Higher clinical scores and loss of body weight were detected in 1.5% compared to 1% DSS treated mice. TINT time intervals showed no dose dependent differences. However, increased clinical scores, body weight reductions, and increased TINT time intervals were detected in Cd14-/- compared to WT mice revealing mouse strain related differences. Therefore, TINT is an easily applicable method for severity assessment in a mouse colitis <span class="hlt">model</span> detecting CD14 related differences, but not dose dependent differences. As TINT revealed most consistent results in group-housed mice, we recommend utilization as an additional method substituting clinical monitoring of the individual mouse. PMID:26637175</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26637175','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26637175"><span id="translatedtitle">Time to Integrate to <span class="hlt">Nest</span> Test Evaluation in a Mouse DSS-Colitis <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>Häger, Christine; Keubler, Lydia M; Biernot, Svenja; Dietrich, Jana; Buchheister, Stephanie; Buettner, Manuela; Bleich, André</p> <p>2015-01-01</p> <p>Severity assessment in laboratory animals is an important issue regarding the implementation of the 3R concept into biomedical research and pivotal in current EU regulations. In mouse <span class="hlt">models</span> of inflammatory bowel disease severity assessment is usually undertaken by clinical scoring, especially by monitoring reduction of body weight. This requires daily observance and handling of each mouse, which is time consuming, stressful for the animal and necessitates an experienced observer. The time to integrate to <span class="hlt">nest</span> test (TINT) is an easily applicable test detecting disturbed welfare by measuring the time interval mice need to integrate <span class="hlt">nesting</span> material to an existing <span class="hlt">nest</span>. Here, TINT was utilized to assess severity in a mouse DSS-colitis <span class="hlt">model</span>. TINT results depended on the group size of mice maintained per cage with most consistent time intervals measured when co-housing 4 to 5 mice. Colitis was induced with 1% or 1.5% DSS in group-housed WT and Cd14-deficient mice. Higher clinical scores and loss of body weight were detected in 1.5% compared to 1% DSS treated mice. TINT time intervals showed no dose dependent differences. However, increased clinical scores, body weight reductions, and increased TINT time intervals were detected in Cd14-/- compared to WT mice revealing mouse strain related differences. Therefore, TINT is an easily applicable method for severity assessment in a mouse colitis <span class="hlt">model</span> detecting CD14 related differences, but not dose dependent differences. As TINT revealed most consistent results in group-housed mice, we recommend utilization as an additional method substituting clinical monitoring of the individual mouse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRD..112.6210B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRD..112.6210B"><span id="translatedtitle">Simulation of a supercellular storm using a three-dimensional <span class="hlt">mesoscale</span> <span class="hlt">model</span> with an explicit lightning flash scheme</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barthe, Christelle; Pinty, Jean-Pierre</p> <p>2007-03-01</p> <p>A complete lightning flash scheme is implemented in the three-dimensional (3-D) nonhydrostatic <span class="hlt">mesoscale</span> <span class="hlt">model</span> Méso-NH of the French community. The scheme, which is part of the electrical scheme, follows a new approach with two steps. First, lightning flashes are <span class="hlt">modeled</span> as bidirectional leaders to mimic the vertical propagation of the initial discharge channels along the electric field. Then, a probabilistic branching algorithm is adapted from the dielectric breakdown concept to reinforce the flash propagation toward distant regions of high charge density but immersed in a weak electric field. This results in a high increase of the total length of the lightning flash channel and also in a better capture of the morphology of intracloud lightning flashes. The electrification and lightning schemes are tested for an ideal case of a supercellular storm. The <span class="hlt">model</span> succeeds in reproducing the general features of a storm and the electric charge cycle. Sensitivity analyses show that the implementation of a branching stage is necessary and efficient enough to relax the growth of the electric field. The intracloud discharges generated by the <span class="hlt">model</span> look realistic with a two-layer horizontal structure extending over tens of kilometers from the triggering area. The lightning flash length and the quantity of charge neutralized are ten times more important when the branching algorithm is taken into account. The main conclusion drawn from this study is the feasibility and the benefit of an advanced treatment of lightning flashes in 3-D numerical simulations with an electrification scheme.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhDT.......153L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT.......153L"><span id="translatedtitle">Permeability of fiber reinforcements for liquid composite molding: Sequential multi-scale investigations into numerical flow <span class="hlt">modeling</span> on the micro- and <span class="hlt">meso-scale</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luchini, Timothy John Franklin</p> <p></p> <p>Composites are complex material mixtures, known to have high amounts of variability, with unique properties at the micro-, meso-, and macro-scales. In the context of advanced textile composite reinforcements, micro-scale refers to aligned fibers and toughening agents in a disordered arrangement; <span class="hlt">meso-scale</span> is the woven, braided, or stitched fabric geometry (which compacts to various volume fractions); and macro-scale is the component or sub-component being produced for a mechanical application. The Darcy-based permeability is an important parameter for <span class="hlt">modeling</span> and understanding the flow profile and fill times for liquid composite molding. Permeability of composite materials can vary widely from the micro- to macro-scales. For example, geometric factors like compaction and ply layup affect the component permeability at the meso- and macro-scales. On the micro-scale the permeability will be affected by the packing arrangement of the fibers and fiber volume fraction. On any scale, simplifications to the geometry can be made to treat the fiber reinforcement as a porous media. Permeability has been widely studied in both experimental and analytical frameworks, but less attention has focused on the ability of numerical tools to predict the permeability of reinforced composite materials. This work aims at (1) predicting permeability at various scales of interest and (2) developing a sequential, multi-scale, numerical <span class="hlt">modeling</span> approach on the micro- and <span class="hlt">meso-scales</span>. First, a micro-scale <span class="hlt">modeling</span> approach is developed, including a geometry generation tool and a fluids-based numerical permeability solver. This micro-scale <span class="hlt">model</span> included all physical fibers and derived the empirical permeability constant directly though numerical simulation. This numerical approach was compared with literature results for perfect packing arrangements, and the results were shown to be comparable with previous work. The numerical simulations described here also extended these previous</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DNP.ND006M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DNP.ND006M"><span id="translatedtitle"><span class="hlt">Modeling</span> nuclear and electronic recoils in noble gas detectors with <span class="hlt">NEST</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mock, Jeremy; NEST Collaboration</p> <p>2015-10-01</p> <p>Noble gases such as xenon and argon are used as targets in single and dual phased rare event detectors like those used in the search for dark matter. Such experiments require an understanding of the behavior of the target material in the presence of low-energy ionizing radiation. This understanding allows an exploration of detector effects such as threshold, energy and position reconstruction, and pulse shape discrimination. The Noble Element Simulation Technique (<span class="hlt">NEST</span>) package is a comprehensive code base that <span class="hlt">models</span> the scintillation and ionization yields from liquid and gaseous xenon and argon in the energy regimes of interest to many types of experiments, like dark matter and neutrino detectors. <span class="hlt">NEST</span> is built on multiple physics <span class="hlt">models</span>, which are constrained by available data for both electronic and nuclear recoils. A substantial body of data exists in the literature, and we are reaching an era in which sub-keV yields can be explored experimentally. Here we present a new global analysis of all available nuclear recoil data, and the latest updates to the electronic recoil <span class="hlt">model</span>, in light of recent low-energy measurements and an improved understanding of detector systematics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1235292','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1235292"><span id="translatedtitle">Top-down estimate of methane emissions in California using a <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> technique: The South Coast Air Basin</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cui, Yu Yan; Brioude, Jerome; McKeen, Stuart A.; Angevine, Wayne M.; Kim, Si -Wan; Frost, Gregory J.; Ahmadov, Ravan; Peischl, Jeff; Bousserez, Nicolas; Liu, Zhen; Ryerson, Thomas B.; Wofsy, Steve C.; Santoni, Gregory W.; Kort, Eric A.; Fischer, Marc L.; Trainer, Michael</p> <p>2015-07-28</p> <p>Methane (CH<sub>4</sub>) is the primary component of natural gas and has a larger global warming potential than CO<sub>2</sub>. Some recent top-down studies based on observations showed CH<sub>4</sub> emissions in California's South Coast Air Basin (SoCAB) were greater than those expected from population-apportioned bottom-up state inventories. In this study, we quantify CH<sub>4 </sub>emissions with an advanced <span class="hlt">mesoscale</span> inverse <span class="hlt">modeling</span> system at a resolution of 8 km × 8 km, using aircraft measurements in the SoCAB during the 2010 Nexus of Air Quality and Climate Change campaign to constrain the inversion. To simulate atmospheric transport, we use the FLEXible PARTicle-Weather Research and Forecasting (FLEXPART-WRF) Lagrangian particle dispersion <span class="hlt">model</span> driven by three configurations of the Weather Research and Forecasting (WRF) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. We determine surface fluxes of CH<sub>4</sub> using a Bayesian least squares method in a four-dimensional inversion. Simulated CH4 concentrations with the posterior emission inventory achieve much better correlations with the measurements (R2 = 0.7) than using the prior inventory (U.S. Environmental Protection Agency's National Emission Inventory 2005, R<sup>2</sup> = 0.5). The emission estimates for CH<sub>4</sub> in the posterior, 46.3 ± 9.2 Mg CH<sub>4</sub>/h, are consistent with published observation-based estimates. Changes in the spatial distribution of CH<sub>4</sub> emissions in the SoCAB between the prior and posterior inventories are discussed. Missing or underestimated emissions from dairies, the oil/gas system, and landfills in the SoCAB seem to explain the differences between the prior and posterior inventories. Furthermore, we estimate that dairies contributed 5.9 ± 1.7 Mg CH<sub>4</sub>/h and the two sectors of oil and gas industries (production and downstream) and landfills together contributed 39.6 ± 8.1 Mg CH<sub>4</sub>/h in the SoCAB.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4276544','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4276544"><span id="translatedtitle">Testing Goodness-of-Fit for the Proportional Hazards <span class="hlt">Model</span> based on <span class="hlt">Nested</span> Case-Control Data</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lu, Wenbin; Liu, Mengling; Chen, Yi-Hau</p> <p>2014-01-01</p> <p>Summary <span class="hlt">Nested</span> case-control sampling is a popular design for large epidemiological cohort studies due to its cost effectiveness. A number of methods have been developed for the estimation of the proportional hazards <span class="hlt">model</span> with <span class="hlt">nested</span> case-control data; however, the evaluation of <span class="hlt">modeling</span> assumption is less attended. In this paper, we propose a class of goodness-of-fit test statistics for testing the proportional hazards assumption based on <span class="hlt">nested</span> case-control data. The test statistics are constructed based on asymptotically mean-zero processes derived from Samuelsen’s maximum pseudo-likelihood estimation method. In addition, we develop an innovative resampling scheme to approximate the asymptotic distribution of the test statistics while accounting for the dependent sampling scheme of <span class="hlt">nested</span> case-control design. Numerical studies are conducted to evaluate the performance of our proposed approach, and an application to the Wilms’ Tumor Study is given to illustrate the methodology. PMID:25298193</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA....11689B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA....11689B"><span id="translatedtitle">Cyclogenesis and severe weather in the vicinity of the Atlas Mountains: studies using a nonhydrostatic <span class="hlt">mesoscale</span> atmospheric <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>Born, K.; Bachner, S.</p> <p>2003-04-01</p> <p>Northwestafrican climate is affected considerably by the Atlas Mountains. Several typical weather phenoma - as extratropical fronts, orographically forced convection, mountain lee cyclogenesis - connected to rainfall variability in arid and semi-arid regions in the northern part of the Sahara and in the Mediterranean are enforced by the mountains. In the framework of the project IMPETUS Westafrica a nonhydrostatic <span class="hlt">mesoscale</span> <span class="hlt">model</span> - the numerical weather prediction <span class="hlt">model</span> "Lokalmodell" (LM) of the German Weather Service - is used to enhance the knowledge about rainfall variability in the Draa river valley, which is located on the southern slope of the High Atlas Mountains. In order to focus on extreme events, two recent cases with severe damages and loss of lifes - the Alger mudflood on Nov 9/10, 2001 and severe floodings in Morocco near Rabat in the week of Dec 3-7, 2002 - are investigated in more detail. The role of the Atlas Mountains is of great importance in these cases, since they act as barrier for maritime moist air and on the other hand as a source of potential vorticity for cyclogenesis. Sensitivity studies on land use characteristics, use of different physical parameterizations, corrections of the initial state of the atmosphere and a simple technique for <span class="hlt">model</span> output statistics contribute to a substantial improvement of rainfall predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1338168','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1338168"><span id="translatedtitle">Radiation-induced aging of PDMS Elastomer TR-55: a summary of constitutive, <span class="hlt">mesoscale</span>, and population-based <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Maiti, A; Weisgraber, T. H.; Dinh, L. N.</p> <p>2016-11-16</p> <p>Filled and cross-linked elastomeric rubbers are versatile network materials with a multitude of applications ranging from artificial organs and biomedical devices to cushions, coatings, adhesives, interconnects, and seismic-isolation-, thermal-, and electrical barriers External factors like mechanical stress, temperature fluctuations, or radiation are known to create chemical changes in such materials that can directly affect the molecular weight distribution (MWD) of the polymer between cross-links and alter the structural and mechanical properties. From a Materials Science point of view it is highly desirable to understand, effect, and manipulate such property changes in a controlled manner. In this report we summarize our <span class="hlt">modeling</span> efforts on a polysiloxane elastomer TR-55, which is an important component in several of our systems, and representative of a wide class of filled rubber materials. The primary aging driver in this work has been γ-radiation, and a variety of <span class="hlt">modeling</span> approaches have been employed, including constitutive, <span class="hlt">mesoscale</span>, and population-based <span class="hlt">models</span>. The work utilizes diverse experimental data, including mechanical stress-strain and compression set measurements, as well as MWD measurements using multiquantum NMR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJMPB..3041002G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJMPB..3041002G"><span id="translatedtitle">The ellipsoidal <span class="hlt">nested</span> sampling and the expression of the <span class="hlt">model</span> uncertainty in measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gervino, Gianpiero; Mana, Giovanni; Palmisano, Carlo</p> <p>2016-07-01</p> <p>In this paper, we consider the problems of identifying the most appropriate <span class="hlt">model</span> for a given physical system and of assessing the <span class="hlt">model</span> contribution to the measurement uncertainty. The above problems are studied in terms of Bayesian <span class="hlt">model</span> selection and <span class="hlt">model</span> averaging. As the evaluation of the “evidence” Z, i.e., the integral of Likelihood × Prior over the space of the measurand and the parameters, becomes impracticable when this space has 20 ÷ 30 dimensions, it is necessary to consider an appropriate numerical strategy. Among the many algorithms for calculating Z, we have investigated the ellipsoidal <span class="hlt">nested</span> sampling, which is a technique based on three pillars: The study of the iso-likelihood contour lines of the integrand, a probabilistic estimate of the volume of the parameter space contained within the iso-likelihood contours and the random samplings from hyperellipsoids embedded in the integration variables. This paper lays out the essential ideas of this approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AdAtS..19..487L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AdAtS..19..487L"><span id="translatedtitle">Climate Simulations based on a different-grid <span class="hlt">nested</span> and coupled <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>Li, Dan; Ji, Jinjun; Li, Yinpeng</p> <p>2002-05-01</p> <p>An atmosphere-vegetation interaction <span class="hlt">model</span> (A VIM) has been coupled with a nine-layer General Cir-culation <span class="hlt">Model</span> (GCM) of Institute of Atmospheic Physics/State Key Laboratory of Numerical <span class="hlt">Modeling</span> for Atmospheric Sciences and Geophysical Fluid Dynamics (IAP/LASG), which is rhomboidally truncated at zonal wave number 15, to simulate global climatic mean states. A VIM is a <span class="hlt">model</span> having inter-feedback between land surface processes and eco-physiological processes on land. As the first step to couple land with atmosphere completely, the physiological processes are fixed and only the physical part (generally named the SVAT (soil-vegetation-atmosphere-transfer scheme) <span class="hlt">model</span>) of AVIM is <span class="hlt">nested</span> into IAP/LASG L9R15 GCM. The ocean part of GCM is prescribed and its monthly sea surface temperature (SST) is the climatic mean value. With respect to the low resolution of GCM, i.e., each grid cell having lon-gitude 7.5° and latitude 4.5°, the vegetation is given a high resolution of 1.5° by 1.5° to <span class="hlt">nest</span> and couple the fine grid cells of land with the coarse grid cells of atmosphere. The coupling <span class="hlt">model</span> has been integrated for 15 years and its last ten-year mean of outputs was chosen for analysis. Compared with observed data and NCEP reanalysis, the coupled <span class="hlt">model</span> simulates the main characteris-tics of global atmospheric circulation and the fields of temperature and moisture. In particular, the simu-lated precipitation and surface air temperature have sound results. The work creates a solid base on coupling climate <span class="hlt">models</span> with the biosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10106224','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10106224"><span id="translatedtitle">Use of cloud observations and <span class="hlt">mesoscale</span> meteorology <span class="hlt">models</span> to evaluate and improve cloud parameterizations. Technical progress report, 1 October 1992--30 September 1993</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Walcek, C.J.</p> <p>1993-09-30</p> <p>This research program utilizes satellite and surface-derived cloud observations together with standard meteorological measurements to evaluate and improve our ability to accurately diagnose cloud coverage. Results of this research will be used to compliment existing or future parameterizations of cloud effects in general circulation <span class="hlt">models</span>, since nearly all cloud parameterizations must specify a fractional area of cloud coverage when calculating radiative or dynamic cloud effects, and current parameterizations rely on rather crude cloud cover estimates. During the first phase of this research program, our goal is to evaluate and improve the methods for calculating cloud cover within a <span class="hlt">mesoscale</span> meteorology <span class="hlt">model</span>. To accomplish this, a <span class="hlt">mesoscale</span> meteorology <span class="hlt">model</span> will be quantitatively evaluated using available cloud cover databases, including the US Air Force 3DNEPH and RTNEPH satellite-derived cloud fields, as well as CART data as they become available. During the second phase of this research, the cloud cover data and improved parameterizations of cloud coverage developed during the first phase will be incorporated into a <span class="hlt">mesoscale</span> meteorology <span class="hlt">model</span>. <span class="hlt">Model</span> forecasts which utilize the observed cloud coverage and depth should be improved relative to forecasts which crudely specify cloud properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812793N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812793N"><span id="translatedtitle">Streamflow hindcasting in European river basins via multi-parametric ensemble of the <span class="hlt">mesoscale</span> hydrologic <span class="hlt">model</span> (mHM)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Noh, Seong Jin; Rakovec, Oldrich; Kumar, Rohini; Samaniego, Luis</p> <p>2016-04-01</p> <p>There have been tremendous improvements in distributed hydrologic <span class="hlt">modeling</span> (DHM) which made a process-based simulation with a high spatiotemporal resolution applicable on a large spatial scale. Despite of increasing information on heterogeneous property of a catchment, DHM is still subject to uncertainties inherently coming from <span class="hlt">model</span> structure, parameters and input forcing. Sequential data assimilation (DA) may facilitate improved streamflow prediction via DHM using real-time observations to correct internal <span class="hlt">model</span> states. In conventional DA methods such as state updating, parametric uncertainty is, however, often ignored mainly due to practical limitations of methodology to specify <span class="hlt">modeling</span> uncertainty with limited ensemble members. If parametric uncertainty related with routing and runoff components is not incorporated properly, predictive uncertainty by DHM may be insufficient to capture dynamics of observations, which may deteriorate predictability. Recently, a multi-scale parameter regionalization (MPR) method was proposed to make hydrologic predictions at different scales using a same set of <span class="hlt">model</span> parameters without losing much of the <span class="hlt">model</span> performance. The MPR method incorporated within the <span class="hlt">mesoscale</span> hydrologic <span class="hlt">model</span> (mHM, http://www.ufz.de/mhm) could effectively represent and control uncertainty of high-dimensional parameters in a distributed <span class="hlt">model</span> using global parameters. In this study, we present a global multi-parametric ensemble approach to incorporate parametric uncertainty of DHM in DA to improve streamflow predictions. To effectively represent and control uncertainty of high-dimensional parameters with limited number of ensemble, MPR method is incorporated with DA. Lagged particle filtering is utilized to consider the response times and non-Gaussian characteristics of internal hydrologic processes. The hindcasting experiments are implemented to evaluate impacts of the proposed DA method on streamflow predictions in multiple European river basins</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4214118','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4214118"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">Model</span> to Select the Ideal Location for New Vineyard Plantations in the Rioja Qualified Denomination of Origin</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Martínez-Cámara, E.; Blanco, J.; Jiménez, E.; Saenz-Díez, J. C.; Rioja, J.</p> <p>2014-01-01</p> <p>La Rioja is the region where the top rated wines from Spain come from and also the origin of one of the most prestigious wines in the world. It is worldwide recognized, not only for the quality of the vine, but also for the many factors involved in the process that are controllable by the farmer, such as fertilizers, irrigation, etc. Likewise, there are other key factors, which cannot be controlled that play, however, a crucial role in the quality of the wine, such as temperature, radiation, humidity, and rainfall. This research is focused on two of these factors: temperature and irradiation. The objective of this paper is to be able to recognize these factors, so as to ensure a proper decision criterion when selecting the best location for new vineyard plantations. To achieve this objective, a <span class="hlt">mesoscale</span> <span class="hlt">model</span> MM5 is used, and its performance is assessed and compared using different parameters, from the grid resolution to the physical parameterization of the <span class="hlt">model</span>. Finally, the study evaluates the impact of the different parameterizations and options for the simulation of meteorological variables particularly relevant when choosing new vineyard sites (rainfall frequency, temperature, and sun exposure). PMID:25386596</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100032010','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100032010"><span id="translatedtitle">Predicting Tropical Cyclogenesis with a Global <span class="hlt">Mesoscale</span> <span class="hlt">Model</span>: Hierarchical Multiscale Interactions During the Formation of Tropical Cyclone Nargis(2008)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shen, B.-W.; Tao, W.-K.; Lau, W. K.; Atlas, R.</p> <p>2010-01-01</p> <p>Very severe cyclonic storm Nargis devastated Burma (Myanmar) in May 2008, caused tremendous damage and numerous fatalities, and became one of the 10 deadliest tropical cyclones (TCs) of all time. To increase the warning time in order to save lives and reduce economic damage, it is important to extend the lead time in the prediction of TCs like Nargis. As recent advances in high-resolution global <span class="hlt">models</span> and supercomputing technology have shown the potential for improving TC track and intensity forecasts, the ability of a global <span class="hlt">mesoscale</span> <span class="hlt">model</span> to predict TC genesis in the Indian Ocean is examined in this study with the aim of improving simulations of TC climate. High-resolution global simulations with real data show that the initial formation and intensity variations of TC Nargis can be realistically predicted up to 5 days in advance. Preliminary analysis suggests that improved representations of the following environmental conditions and their hierarchical multiscale interactions were the key to achieving this lead time: (1) a westerly wind burst and equatorial trough, (2) an enhanced monsoon circulation with a zero wind shear line, (3) good upper-level outflow with anti-cyclonic wind shear between 200 and 850 hPa, and (4) low-level moisture convergence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25386596','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25386596"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">model</span> to select the ideal location for new vineyard plantations in the Rioja qualified denomination of origin.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martínez-Cámara, E; Blanco, J; Jiménez, E; Saenz-Díez, J C; Rioja, J</p> <p>2014-01-01</p> <p>La Rioja is the region where the top rated wines from Spain come from and also the origin of one of the most prestigious wines in the world. It is worldwide recognized, not only for the quality of the vine, but also for the many factors involved in the process that are controllable by the farmer, such as fertilizers, irrigation, etc. Likewise, there are other key factors, which cannot be controlled that play, however, a crucial role in the quality of the wine, such as temperature, radiation, humidity, and rainfall. This research is focused on two of these factors: temperature and irradiation. The objective of this paper is to be able to recognize these factors, so as to ensure a proper decision criterion when selecting the best location for new vineyard plantations. To achieve this objective, a <span class="hlt">mesoscale</span> <span class="hlt">model</span> MM5 is used, and its performance is assessed and compared using different parameters, from the grid resolution to the physical parameterization of the <span class="hlt">model</span>. Finally, the study evaluates the impact of the different parameterizations and options for the simulation of meteorological variables particularly relevant when choosing new vineyard sites (rainfall frequency, temperature, and sun exposure).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JGRD..11124201C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JGRD..11124201C"><span id="translatedtitle">A one-dimensional sectional aerosol <span class="hlt">model</span> integrated with <span class="hlt">mesoscale</span> meteorological data to study marine boundary layer aerosol dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caffrey, Peter F.; Hoppel, William A.; Shi, Jainn J.</p> <p>2006-12-01</p> <p>The dynamics of aerosols in the marine boundary layer are simulated with a one-dimensional, multicomponent, sectional aerosol <span class="hlt">model</span> using vertical profiles of turbulence, relative humidity, temperature, vertical velocity, cloud cover, and precipitation provided by 3-D <span class="hlt">mesoscale</span> meteorological <span class="hlt">model</span> output. The Naval Research Laboratory's (NRL) sectional aerosol <span class="hlt">model</span> MARBLES (Fitzgerald et al., 1998a) was adapted to use hourly meteorological input taken from NRL's Coupled Ocean-Atmosphere Prediction System (COAMPS). COAMPS-generated turbulent mixing coefficients and large-scale vertical velocities determine vertical exchange within the marine boundary layer and exchange with the free troposphere. Air mass back trajectories were used to define the air column history along which the meteorology was retrieved for use with the aerosol <span class="hlt">model</span>. Details on the integration of these <span class="hlt">models</span> are described here, as well as a description of improvements made to the aerosol <span class="hlt">model</span>, including transport by large-scale vertical motions (such as subsidence and lifting), a revised sea-salt aerosol source function, and separate tracking of sulfate mass from each of the five sources (free tropospheric, nucleated, condensed from gas phase oxidation products, cloud-processed, and produced from heterogeneous oxidation of S(IV) on sea-salt aerosol). Results from <span class="hlt">modeling</span> air masses arriving at Oahu, Hawaii, are presented, and the relative contribution of free-tropospheric sulfate particles versus sea-salt aerosol from the surface to CCN concentrations is discussed. Limitations and benefits of the method are presented, as are sensitivity analyses of the effect of large-scale vertical motions versus turbulent mixing.</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('https://www.osti.gov/scitech/biblio/6767552','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6767552"><span id="translatedtitle">Morphology of <span class="hlt">nested</span> fullerenes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Srolovitz, D.J.; Safran, S.A.; Homyonfer, M.; Tenne, R. )</p> <p>1995-03-06</p> <p>We introduce a continuum <span class="hlt">model</span> which shows that dislocations and/or grain boundaries are intrinsic features of <span class="hlt">nested</span> fullerenes whose thickness exceeds a critical value to relieve the large inherent strains in these structures. The ratio of the thickness to the radius of the <span class="hlt">nested</span> fullerenes is determined by the ratio of the surface to curvature and dislocation (or grain boundary) energies. Confirming experimental evidence is presented for <span class="hlt">nested</span> fullerenes with small thicknesses and with spherosymmetric shapes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JCli...19..139W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JCli...19..139W"><span id="translatedtitle">Two- and Three-Dimensional Cloud-Resolving <span class="hlt">Model</span> Simulations of the <span class="hlt">Mesoscale</span> Enhancement of Surface Heat Fluxes by Precipitating Deep Convection.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Xiaoqing; Guimond, Stephen</p> <p>2006-01-01</p> <p>Two-dimensional (2D) and three-dimensional (3D) cloud-resolving <span class="hlt">model</span> (CRM) simulations are conducted to quantify the enhancement of surface sensible and latent heat fluxes by tropical precipitating cloud systems for 20 days (10 30 December 1992) during the Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment (TOGA COARE). The <span class="hlt">mesoscale</span> enhancement appears to be analogous across both 2D and 3D CRMs, with the enhancement for the sensible heat flux accounting for 17% of the total flux for each <span class="hlt">model</span> and the enhancement for the latent heat flux representing 18% and 16% of the total flux for 2D and 3D CRMs, respectively. The convection-induced gustiness is mainly responsible for the enhancement observed in each <span class="hlt">model</span> simulation. The parameterization schemes of the <span class="hlt">mesoscale</span> enhancement by the gustiness in terms of convective updraft, downdraft, and precipitation, respectively, are examined using each version of the CRM. The scheme utilizing the precipitation was found to yield the most desirable estimations of the mean fluxes with the smallest rms error. The results together with previous findings from other studies suggest that the <span class="hlt">mesoscale</span> enhancement of surface heat fluxes by the precipitating deep convection is a subgrid process apparent across various CRMs and is imperative to incorporate into general circulation <span class="hlt">models</span> (GCMs) for improved climate simulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970023066','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970023066"><span id="translatedtitle">Workstation-Based Real-Time <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> Designed for Weather Support to Operations at the Kennedy Space Center and Cape Canaveral Air Station</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Manobianco, John; Zack, John W.; Taylor, Gregory E.</p> <p>1996-01-01</p> <p>This paper describes the capabilities and operational utility of a version of the <span class="hlt">Mesoscale</span> Atmospheric Simulation System (MASS) that has been developed to support operational weather forecasting at the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). The implementation of local, <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> systems at KSC/CCAS is designed to provide detailed short-range (less than 24 h) forecasts of winds, clouds, and hazardous weather such as thunderstorms. Short-range forecasting is a challenge for daily operations, and manned and unmanned launches since KSC/CCAS is located in central Florida where the weather during the warm season is dominated by <span class="hlt">mesoscale</span> circulations like the sea breeze. For this application, MASS has been modified to run on a Stardent 3000 workstation. Workstation-based, real-time numerical <span class="hlt">modeling</span> requires a compromise between the requirement to run the system fast enough so that the output can be used before expiration balanced against the desire to improve the simulations by increasing resolution and using more detailed physical parameterizations. It is now feasible to run high-resolution <span class="hlt">mesoscale</span> <span class="hlt">models</span> such as MASS on local workstations to provide timely forecasts at a fraction of the cost required to run these <span class="hlt">models</span> on mainframe supercomputers. MASS has been running in the Applied Meteorology Unit (AMU) at KSC/CCAS since January 1994 for the purpose of system evaluation. In March 1995, the AMU began sending real-time MASS output to the forecasters and meteorologists at CCAS, Spaceflight Meteorology Group (Johnson Space Center, Houston, Texas), and the National Weather Service (Melbourne, Florida). However, MASS is not yet an operational system. The final decision whether to transition MASS for operational use will depend on a combination of forecaster feedback, the AMU's final evaluation results, and the life-cycle costs of the operational system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA546275','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA546275"><span id="translatedtitle">A Study of Spectral Element and Discontinuous Galerkin Methods for the Navier-Stokes Equations in Nonhydrostatic <span class="hlt">Mesoscale</span> Atmospheric <span class="hlt">Modeling</span>: Equation Sets and Test Cases</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2008-01-01</p> <p>Equation sets and test casesq F.X. Giraldo a,*, M. Restelli b aDepartment of Applied Mathematics, Naval Postgraduate School, 833 Dyer Road, Monterey, CA...93943, USA bMOX–Modellistica e Calcolo Scientifico, Dipartimento di Matematica , ‘‘F. Brioschi”, Politecnico di Milano, via Bonardi 9 20133 Milano...are of importance in nonhydrostatic <span class="hlt">mesoscale</span> atmospheric <span class="hlt">modeling</span>. We study three different forms of the governing equations using seven test cases</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996PhDT........43C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996PhDT........43C"><span id="translatedtitle">Investigation of <span class="hlt">Mesoscale</span> Circulations Induced by Surface Processes with Special Emphasis on Carolina Coastal Front</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chanumalla, Neeraja R.</p> <p></p> <p> landuse patterns affects significantly, the location, vertical structure and the depth of the coastal front. Also, several other <span class="hlt">mesoscale</span> phenomena such as the low level jet associated with the Carolina coastal front are closer to observations using the soil moisture. Sensitivity of monsoon rainfall to different ambient wind speeds, orography and wind shear was studied using a two-dimensional <span class="hlt">mesoscale</span> <span class="hlt">model</span>. The two-dimensional simulations show the existence of a sea-breeze type of <span class="hlt">mesoscale</span> circulation over the Western Ghats during the monsoon season. This circulation enhances precipitation. NRL/NCSU three dimensional <span class="hlt">nested</span> <span class="hlt">model</span> was used to investigate the sensitivity of summer monsoon circulations to the soil moisture and vegetation characteristics. The results indicated that vegetation, soil types and initial soil moisture availability affect the <span class="hlt">mesoscale</span> variation and the amount of monsoon rainfall significantly. Enhanced <span class="hlt">mesoscale</span> circulations in the <span class="hlt">model</span> with vegetation increased convection which in turn increased the magnitude of the upper tropospheric easterly jet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26177286','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26177286"><span id="translatedtitle">Using Field Data and GIS-Derived Variables to <span class="hlt">Model</span> Occurrence of Williamson's Sapsucker <span class="hlt">Nesting</span> Habitat at Multiple Spatial Scales.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Drever, Mark C; Gyug, Les W; Nielsen, Jennifer; Stuart-Smith, A Kari; Ohanjanian, I Penny; Martin, Kathy</p> <p>2015-01-01</p> <p>Williamson's sapsucker (Sphyrapicus thyroideus) is a migratory woodpecker that breeds in mixed coniferous forests in western North America. In Canada, the range of this woodpecker is restricted to three small populations in southern British Columbia, precipitating a national listing as 'Endangered' in 2005, and the need to characterize critical habitat for its survival and recovery. We compared habitat attributes between Williamson's sapsucker <span class="hlt">nest</span> territories and random points without <span class="hlt">nests</span> or detections of this sapsucker as part of a resource selection analysis to identify the habitat features that best explain the probability of <span class="hlt">nest</span> occurrence in two separate geographic regions in British Columbia. We compared the relative explanatory power of generalized linear <span class="hlt">models</span> based on field-derived and Geographic Information System (GIS) data within both a 225 m and 800 m radius of a <span class="hlt">nest</span> or random point. The <span class="hlt">model</span> based on field-derived variables explained the most variation in <span class="hlt">nest</span> occurrence in the Okanagan-East Kootenay Region, whereas <span class="hlt">nest</span> occurrence was best explained by GIS information at the 800 m scale in the Western Region. Probability of <span class="hlt">nest</span> occurrence was strongly tied to densities of potential <span class="hlt">nest</span> trees, which included open forests with very large (diameter at breast height, DBH, ≥57.5 cm) western larch (Larix occidentalis) trees in the Okanagan-East Kootenay Region, and very large ponderosa pine (Pinus ponderosa) and large (DBH 17.5-57.5 cm) trembling aspen (Populus tremuloides) trees in the Western Region. Our results have the potential to guide identification and protection of critical habitat as required by the Species at Risk Act in Canada, and to better manage Williamson's sapsucker habitat overall in North America. In particular, management should focus on the maintenance and recruitment of very large western larch and ponderosa pine trees.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DFDG30008P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DFDG30008P"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Ocean Large Eddy Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pearson, Brodie; Fox-Kemper, Baylor; Bachman, Scott; Bryan, Frank</p> <p>2015-11-01</p> <p>The highest resolution global climate <span class="hlt">models</span> (GCMs) can now resolve the largest scales of <span class="hlt">mesoscale</span> dynamics in the ocean. This has the potential to increase the fidelity of GCMs. However, the effects of the smallest, unresolved, scales of <span class="hlt">mesoscale</span> dynamics must still be parametrized. One such family of parametrizations are <span class="hlt">mesoscale</span> ocean large eddy simulations (MOLES), but the effects of including MOLES in a GCM are not well understood. In this presentation, several MOLES schemes are implemented in a <span class="hlt">mesoscale</span>-resolving GCM (CESM), and the resulting flow is compared with that produced by more traditional sub-grid parametrizations. Large eddy simulation (LES) is used to simulate flows where the largest scales of turbulent motion are resolved, but the smallest scales are not resolved. LES has traditionally been used to study 3D turbulence, but recently it has also been applied to idealized 2D and quasi-geostrophic (QG) turbulence. The MOLES presented here are based on 2D and QG LES schemes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS43C1299F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS43C1299F"><span id="translatedtitle">Effect of the <span class="hlt">Mesoscale</span> on Southern Ocean Water Mass Structure and Properties - Assessment Based on a Suite of <span class="hlt">Model</span> Simulations of Varying Resolution.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frenger, I.; Sarmiento, J. L.; Dufour, C. O.; de Souza, G.</p> <p>2014-12-01</p> <p>The Southern Ocean is crucial in taking up excess heat and anthropogenic carbon. At the same time, it is an ocean region which is typically poorly simulated by <span class="hlt">models</span> used for climate projections. One major source of uncertainty is the representation of the effects of ocean <span class="hlt">mesoscale</span> processes, which are subgrid scale in current climate simulations. This project examines a suite of three simulations carried out with the same coupled climate <span class="hlt">model</span> but varying spatial resolutions of the ocean: it consists of a coarse 1º-resolution where eddy effects are parameterized, a modest-eddying 0.25º-simulation lacking an eddy parameterization, and an actively-eddying 0.1º-simulation. Differences between the simulations are analyzed in a water mass framework, which is a "natural" approach given that water masses are inherently linked to ocean circulation and are sensitive to changes of their formation processes. The questions that will be examined are: first if the <span class="hlt">mesoscale</span> processes in the Southern Ocean act to thin intermediate waters and second if they add zonal structure to the water masses. We will further examine the skill of the coarse resolution ocean <span class="hlt">model</span> to reproduce these hypothesized effects of the <span class="hlt">mesoscale</span> with a state-of-the-art parameterization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10192259','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10192259"><span id="translatedtitle">Development of advanced cloud parameterizations to examine air quality, cloud properties, and cloud-radiation feedback in <span class="hlt">mesoscale</span> <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lee, In Young</p> <p>1993-09-01</p> <p>The distribution of atmospheric pollutants is governed by dynamic processes that create the general conditions for transport and mixing, by microphysical processes that control the evolution of aerosol and cloud particles, and by chemical processes that transform chemical species and form aerosols. Pollutants emitted into the air can undergo homogeneous gas reactions to create a suitable environment for the production by heterogeneous nucleation of embryos composed of a few molecules. The physicochemical properties of preexisting aerosols interact with newly produced embryos to evolve by heteromolecular diffusion and coagulation. Hygroscopic particles wig serve as effective cloud condensation nuclei (CCN), while hydrophobic particles will serve as effective ice-forming nuclei. Clouds form initially by condensation of water vapor on CCN and evolve in a vapor-liquid-solid system by deposition, sublimation, freezing, melting, coagulation, and breakup. Gases and aerosols that enter the clouds undergo aqueous chemical processes and may acidity hydrometer particles. Calculations for solar and longwave radiation fluxes depend on how the respective spectra are modified by absorbers such as H{sub 2}O, CO{sub 2}, O{sub 3}, CH{sub 4}, N{sub 2}O, chlorofruorocarbons, and aerosols. However, the flux calculations are more complicated for cloudy skies, because the cloud optical properties are not well defined. In this paper, key processes such as tropospheric chemistry, cloud microphysics parameterizations, and radiation schemes are reviewed in terms of physicochemical processes occurring, and recommendations are made for the development of advanced modules applicable to <span class="hlt">mesoscale</span> <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARX19009T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARX19009T"><span id="translatedtitle">Electronic and Magnetic Properties of Transition-Metal Oxide Nanocomposites: A Tight-Binding <span class="hlt">Modeling</span> at <span class="hlt">Mesoscale</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tai, Yuan-Yen; Zhu, Jian-Xin</p> <p></p> <p>Transition metal oxides (TMOs) exhibit many emergent phenomena ranging from high-temperature superconductivity and giant magnetoresistance to magnetism and ferroelectricity. In addition, when TMOs are interfaced with each other, new functionalities can arise, which are absent in individual components. In this talk, I will present an overview on our recent efforts in theoretical understanding of the electronic and magnetic properties TMO nanocomposites. In particular, I will introduce our recently developed tight-binding <span class="hlt">modeling</span> of these properties arising from the interplay of competing interactions at the interfaces of planar and pillar nanocomposites. Our theoretical tool package will provide a unique capability to address the emergent phenomena in TMO nanocomposites and their <span class="hlt">mesoscale</span> response to such effects like strain and microstructures at the interfaces, and ultimately help establish design principles of new multifunctionality with TMOs. This work was carried out under the auspices of the National Nuclear Security Administration of the U.S. Department of Energy at LANL under Contract No. DE-AC52-06NA25396, and was supported by the LANL LDRD Program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JOM....68k2754A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JOM....68k2754A"><span id="translatedtitle">Development of a High-Temperature Tensile Tester for Micromechanical Characterization of Materials Supporting <span class="hlt">Meso-Scale</span> ICME <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>Alam, Zafir; Eastman, David; Jo, Minjea; Hemker, Kevin</p> <p>2016-11-01</p> <p>A high-temperature tensile tester (HTTT) has been established for the evaluation of micro-mechanical properties of materials at the <span class="hlt">meso-scale</span>. Metals and ceramics can now be tested at temperatures and strain rates between room temperature and 1200°C and 10-5 s-1 to 10-1 s-1, respectively. The samples are heated in a compact clam shell furnace and strain is measured directly in the sample gage with digital image correlation. The HTTT extracts representative mechanical properties, as evidenced by the similarity in the evaluated micro-tensile properties of a solid solution-strengthened Ni-base superalloy Ni-625 with that of the bulk. The effectiveness of the HTTT has also been demonstrated in evaluating the tensile and stress relaxation/short-term creep properties of a polycrystalline Ni-base superalloy René 88DT. The versatility in carrying out tensile, short-term creep, bend tests, and fracture toughness measurements makes the HTTT a robust experimental tool for small-scale and scale-specific benchmarking of multi-scale ICME <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27979678','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27979678"><span id="translatedtitle">Mathematical <span class="hlt">model</span> for path selection by ants between <span class="hlt">nest</span> and food source.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bodnar, Marek; Okińczyc, Natalia; Vela-Pérez, M</p> <p>2017-03-01</p> <p>Several <span class="hlt">models</span> have been proposed to describe the behavior of ants when moving from <span class="hlt">nest</span> to food sources. Most of these studies where based on numerical simulations with no mathematical justification. In this paper, we propose a mechanism for the formation of paths of minimal length between two points by a collection of individuals undergoing reinforced random walks taking into account not only the lengths of the paths but also the angles (connected to the preference of ants to move along straight lines). Our <span class="hlt">model</span> involves reinforcement (pheromone accumulation), persistence (tendency to preferably follow straight directions in absence of any external effect) and takes into account the bifurcation angles of each edge (represented by a probability of willingness of choosing the path with the smallest angle). We describe analytically the results for 2 ants and different path lengths and numerical simulations for several ants.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4789134','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4789134"><span id="translatedtitle">Comparing Treatment Policies with Assistance from the Structural <span class="hlt">Nested</span> Mean <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>Lu, Xi; Lynch, Kevin G.; Oslin, David W.; Murphy, Susan</p> <p>2015-01-01</p> <p>Summary Treatment policies, also known as dynamic treatment regimes, are sequences of decision rules that link the observed patient history with treatment recommendations. Multiple, plausible, treatment policies are frequently constructed by researchers using expert opinion, theories and reviews of the literature. Often these different policies represent competing approaches to managing an illness. Here we develop an “assisted estimator” that can be used to compare the mean outcome of competing treatment policies. The term “assisted” refers to the fact estimators from the Structural <span class="hlt">Nested</span> Mean <span class="hlt">Model</span>, a parametric <span class="hlt">model</span> for the causal effect of treatment at each time point, are used in the process of estimating the mean outcome. This work is motivated by our work on comparing the mean outcome of two competing treatment policies using data from the ExTENd study in alcohol dependence. PMID:26363892</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011BoLMe.139..121R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011BoLMe.139..121R"><span id="translatedtitle">The Simulation of the Opposing Fluxes of Latent Heat and CO2 over Various Land-Use Types: Coupling a Gas Exchange <span class="hlt">Model</span> to a <span class="hlt">Mesoscale</span> Atmospheric <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>Reyers, Mark; Krüger, Andreas; Werner, Christiane; Pinto, Joaquim G.; Zacharias, Stefan; Kerschgens, Michael</p> <p>2011-04-01</p> <p>A <span class="hlt">mesoscale</span> meteorological <span class="hlt">model</span> (FOOT3DK) is coupled with a gas exchange <span class="hlt">model</span> to simulate surface fluxes of CO2 and H2O under field conditions. The gas exchange <span class="hlt">model</span> consists of a C3 single leaf photosynthesis sub-<span class="hlt">model</span> and an extended big leaf (sun/shade) sub-<span class="hlt">model</span> that divides the canopy into sunlit and shaded fractions. Simulated CO2 fluxes of the stand-alone version of the gas exchange <span class="hlt">model</span> correspond well to eddy-covariance measurements at a test site in a rural area in the west of Germany. The coupled FOOT3DK/gas exchange <span class="hlt">model</span> is validated for the diurnal cycle at singular grid points, and delivers realistic fluxes with respect to their order of magnitude and to the general daily course. Compared to the Jarvis-based big leaf scheme, simulations of latent heat fluxes with a photosynthesis-based scheme for stomatal conductance are more realistic. As expected, flux averages are strongly influenced by the underlying land cover. While the simulated net ecosystem exchange is highly correlated with leaf area index, this correlation is much weaker for the latent heat flux. Photosynthetic CO2 uptake is associated with transpirational water loss via the stomata, and the resulting opposing surface fluxes of CO2 and H2O are reproduced with the <span class="hlt">model</span> approach. Over vegetated surfaces it is shown that the coupling of a photosynthesis-based gas exchange <span class="hlt">model</span> with the land-surface scheme of a <span class="hlt">mesoscale</span> <span class="hlt">model</span> results in more realistic simulated latent heat fluxes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930055298&hterms=cold+front&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcold%2Bfront','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930055298&hterms=cold+front&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dcold%2Bfront"><span id="translatedtitle">A nonhydrostatic version of the Penn State-NCAR <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> - Validation tests and simulation of an Atlantic cyclone and cold front</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dudhia, Jimy</p> <p>1993-01-01</p> <p>A nonhydrostatic extension to the Pennsylvania State University-NCAR <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> is presented, which employs reference pressure as the basis for a terrain-following vertical coordinate, and the fully compressible system of equations. It is shown that this <span class="hlt">model</span>, combined with the existing initialization techniques and the physics of the current hydrostatic <span class="hlt">model</span>, is capable of real-data simulations on any scale, limited only by data quality and resolution and by computer resources. An example of an explosive cyclone simulation is presented, demonstrating the capability of the nonhydrostatic <span class="hlt">model</span> to reproduce the hydrostatic <span class="hlt">model</span> results at large scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6441T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6441T"><span id="translatedtitle">Simulation of Storm Surge by a Depth-integrated Non-hydrostatic <span class="hlt">Nested</span>-gird <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>Tsai, Yu-Lin; Wu, Tso-Ren; Terng, Chuen-Teyr; Cheung, Mei-Hui</p> <p>2015-04-01</p> <p>This paper presents COMCOT-SS (COrnell Multi-grid Coupled of Tsunami <span class="hlt">Model</span> - Storm Surge) operational <span class="hlt">model</span>, a depth integrated non-hydrostatic storm surge <span class="hlt">model</span> developed for the Central Weather Bureau (CWB) in Taiwan. This <span class="hlt">model</span> is based on the widely-validated COMCOT tsunami <span class="hlt">model</span>. However, the governing equations were modified to be a depth-integrated vertical momentum equation, and the nonlinear shallow water equations including extra terms, such as the non-hydrostatic pressure, weather forcing, and tidal terms. The non-hydrostatic term enables the <span class="hlt">model</span> to simulate relatively steep waves in the near-shore region. The conventional features in COMCOT, such as the <span class="hlt">nested</span>-grid system, spherical and Cartesian coordinate systems, and the moving boundary scheme for inundation prediction were preserved. In this study, we carefully validated the <span class="hlt">model</span> with analytic solutions for wind shear stress and pressure gradient terms. TWRF (Typhoon Weather Research and Forecasting) <span class="hlt">model</span> was coupled for providing the meteorological forces generated by typhoons. Besides, parametric typhoon <span class="hlt">models</span> such as Holland <span class="hlt">model</span> (1980) and CWB <span class="hlt">model</span> were also coupled with COMCOT-SS in which the drag coefficient was advised by Large and Pond (1981) and Powell (2003). Astronomical tide provided by the TPXO global tidal <span class="hlt">model</span> was imported from the domain boundaries. As for the <span class="hlt">model</span> performance, COMCOT-SS spends less than 30 minutes to finish a 48-hrs forecasting with a large computational domain which covers Taiwan Strait and most parts of Western Pacific Ocean and South China Sea and satisfies the requirement of early warning. In this paper, we also presented the results of nine typical typhoon routes defined by CWB in Taiwan for the <span class="hlt">model</span> verification. The simulation results accompanied with the non-hydrostatic effect presented good agreement with observation data. Detailed results and discussion will be presented in EGU, 2015.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JPhCS.524a2116H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JPhCS.524a2116H"><span id="translatedtitle">Improvement of AEP Predictions Using Diurnal CFD <span class="hlt">Modelling</span> with Site-Specific Stability Weightings Provided from <span class="hlt">Mesoscale</span> Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hristov, Y.; Oxley, G.; Žagar, M.</p> <p>2014-06-01</p> <p>The Bolund measurement campaign, performed by Danish Technical University (DTU) Wind Energy Department (also known as RISØ), provided significant insight into wind flow <span class="hlt">modeling</span> over complex terrain. In the blind comparison study several <span class="hlt">modelling</span> solutions were submitted with the vast majority being steady-state Computational Fluid Dynamics (CFD) approaches with two equation k-epsilon turbulence closure. This approach yielded the most accurate results, and was identified as the state-of-the-art tool for wind turbine generator (WTG) micro-siting. Based on the findings from Bolund, further comparison between CFD and field measurement data has been deemed essential in order to improve simulation accuracy for turbine load and long-term Annual Energy Production (AEP) estimations. Vestas Wind Systems A/S is a major WTG original equipment manufacturer (OEM) with an installed base of over 60GW in over 70 countries accounting for 19% of the global installed base. The Vestas Performance and Diagnostic Centre (VPDC) provides online live data to more than 47GW of these turbines allowing a comprehensive comparison between <span class="hlt">modelled</span> and real-world energy production data. In previous studies, multiple sites have been simulated with a steady neutral CFD formulation for the atmospheric surface layer (ASL), and wind resource (RSF) files have been generated as a base for long-term AEP predictions showing significant improvement over predictions performed with the industry standard linear WAsP tool. In this study, further improvements to the wind resource file generation with CFD are examined using an unsteady diurnal cycle approach with a full atmospheric boundary layer (ABL) formulation, with the unique stratifications throughout the cycle weighted according to <span class="hlt">mesoscale</span> simulated sectorwise stability frequencies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC41B1098Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC41B1098Y"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> of Smoke Particles Distribution and Their Radiative Feedback over Northern Sub-Saharan African Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yue, Y.; Wang, J.; Ichoku, C. M.; Ellison, L.</p> <p>2015-12-01</p> <p>Stretching from southern boundary of Sahara to the equator and expanding west to east from Atlantic Ocean coasts to the India Ocean coasts, the northern sub-Saharan African (NSSA) region has been subject to intense biomass burning. Comprised of savanna, shrub, tropical forest and a number of agricultural crops, the extensive fires burn belt covers central and south of NSSA during dry season (from October to March) contributes to one of the highest biomass burning rate per km2 in the world. Due to smoke particles' absorption effects of solar radiation, they can modify the surface and atmosphere temperature and thus change atmospheric stability, height of the boundary layer, regional atmospheric circulation, evaporation rate, cloud formation, and precipitation. Hence, smoke particles emitted from biomass burning over NSSA region has a significant influence to the air quality, weather and climate variability. In this study, the first version of this Fire Energetics and Emissions Research (FEER.v1) emissions of several smoke constituents including light-absorbing organic carbon (OC) and black carbon (BC) are applied to a state-of-science meteorology-chemistry <span class="hlt">model</span> as NOAA Weather Research and Forecasting <span class="hlt">Model</span> with Chemistry (WRF-Chem). We analyzed WRF-Chem simulations of surface and vertical distribution of various pollutants and their direct radiative effects in conjunction with satellite observation data from Moderate Resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar data with Orthogonal Polarization (CALIPSO) to strengthen the importance of combining space measured emission products like FEER.v1 emission inventory with <span class="hlt">mesoscale</span> <span class="hlt">model</span> over intense biomass burning region, especially in area where ground-based air-quality and radiation-related observations are limited or absent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7162M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7162M"><span id="translatedtitle"><span class="hlt">Nested</span> 1D-2D approach for urban surface flood <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>Murla, Damian; Willems, Patrick</p> <p>2015-04-01</p> <p>Floods in urban areas as a consequence of sewer capacity exceedance receive increased attention because of trends in urbanization (increased population density and impermeability of the surface) and climate change. Despite the strong recent developments in numerical <span class="hlt">modeling</span> of water systems, urban surface flood <span class="hlt">modeling</span> is still a major challenge. Whereas very advanced and accurate flood <span class="hlt">modeling</span> systems are in place and operation by many river authorities in support of flood management along rivers, this is not yet the case in urban water management. Reasons include the small scale of the urban inundation processes, the need to have very high resolution topographical information available, and the huge computational demands. Urban drainage related inundation <span class="hlt">modeling</span> requires a 1D full hydrodynamic <span class="hlt">model</span> of the sewer network to be coupled with a 2D surface flood <span class="hlt">model</span>. To reduce the computational times, 0D (flood cones), 1D/quasi-2D surface flood <span class="hlt">modeling</span> approaches have been developed and applied in some case studies. In this research, a <span class="hlt">nested</span> 1D/2D hydraulic <span class="hlt">model</span> has been developed for an urban catchment at the city of Gent (Belgium), linking the underground sewer (minor system) with the overland surface (major system). For the overland surface flood <span class="hlt">modelling</span>, comparison was made of 0D, 1D/quasi-2D and full 2D approaches. The approaches are advanced by considering <span class="hlt">nested</span> 1D-2D approaches, including infiltration in the green city areas, and allowing the effects of surface storm water storage to be simulated. An optimal <span class="hlt">nested</span> combination of three different mesh resolutions was identified; based on a compromise between precision and simulation time for further real-time flood forecasting, warning and control applications. Main streets as mesh zones together with buildings as void regions constitute one of these mesh resolution (3.75m2 - 15m2); they have been included since they channel most of the flood water from the manholes and they improve the accuracy of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3858107','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3858107"><span id="translatedtitle">Causal Inference in Occupational Epidemiology: Accounting for the Healthy Worker Effect by Using Structural <span class="hlt">Nested</span> <span class="hlt">Models</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>Naimi, Ashley I.; Richardson, David B.; Cole, Stephen R.</p> <p>2013-01-01</p> <p>In a recent issue of the Journal, Kirkeleit et al. (Am J Epidemiol. 2013;177(11):1218–1224) provided empirical evidence for the potential of the healthy worker effect in a large cohort of Norwegian workers across a range of occupations. In this commentary, we provide some historical context, define the healthy worker effect by using causal diagrams, and use simulated data to illustrate how structural <span class="hlt">nested</span> <span class="hlt">models</span> can be used to estimate exposure effects while accounting for the healthy worker survivor effect in 4 simple steps. We provide technical details and annotated SAS software (SAS Institute, Inc., Cary, North Carolina) code corresponding to the example analysis in the Web Appendices, available at http://aje.oxfordjournals.org/. PMID:24077092</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://www.ncbi.nlm.nih.gov/pubmed/24077092','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24077092"><span id="translatedtitle">Causal inference in occupational epidemiology: accounting for the healthy worker effect by using structural <span class="hlt">nested</span> <span class="hlt">models</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Naimi, Ashley I; Richardson, David B; Cole, Stephen R</p> <p>2013-12-15</p> <p>In a recent issue of the Journal, Kirkeleit et al. (Am J Epidemiol. 2013;177(11):1218-1224) provided empirical evidence for the potential of the healthy worker effect in a large cohort of Norwegian workers across a range of occupations. In this commentary, we provide some historical context, define the healthy worker effect by using causal diagrams, and use simulated data to illustrate how structural <span class="hlt">nested</span> <span class="hlt">models</span> can be used to estimate exposure effects while accounting for the healthy worker survivor effect in 4 simple steps. We provide technical details and annotated SAS software (SAS Institute, Inc., Cary, North Carolina) code corresponding to the example analysis in the Web Appendices, available at http://aje.oxfordjournals.org/.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70047815','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70047815"><span id="translatedtitle">Increased flexibility for <span class="hlt">modeling</span> telemetry and <span class="hlt">nest</span>-survival data using the multistate framework</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Devineau, Olivier; Kendall, William L.; Doherty, Paul F.; Shenk, Tanya M.; White, Gary C.; Lukacs, Paul M.; Burnham, Kenneth P.</p> <p>2014-01-01</p> <p>Although telemetry is one of the most common tools used in the study of wildlife, advances in the analysis of telemetry data have lagged compared to progress in the development of telemetry devices. We demonstrate how standard known-fate telemetry and related <span class="hlt">nest</span>-survival data analysis <span class="hlt">models</span> are special cases of the more general multistate framework. We present a short theoretical development, and 2 case examples regarding the American black duck and the mallard. We also present a more complex lynx data analysis. Although not necessary in all situations, the multistate framework provides additional flexibility to analyze telemetry data, which may help analysts and biologists better deal with the vagaries of real-world data collection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2875310','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2875310"><span id="translatedtitle">Structural <span class="hlt">Nested</span> Mean <span class="hlt">Models</span> for Assessing Time-Varying Effect Moderation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Almirall, Daniel; Ten Have, Thomas; Murphy, Susan A.</p> <p>2009-01-01</p> <p>SUMMARY This article considers the problem of assessing causal effect moderation in longitudinal settings in which treatment (or exposure) is time-varying and so are the covariates said to moderate its effect. Intermediate Causal Effects that describe time-varying causal effects of treatment conditional on past covariate history are introduced and considered as part of Robins’ Structural <span class="hlt">Nested</span> Mean <span class="hlt">Model</span>. Two estimators of the intermediate causal effects, and their standard errors, are presented and discussed: The first is a proposed 2-Stage Regression Estimator. The second is Robins’ G-Estimator. The results of a small simulation study that begins to shed light on the small versus large sample performance of the estimators, and on the bias-variance trade-off between the two estimators are presented. The methodology is illustrated using longitudinal data from a depression study. PMID:19397586</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT.......114K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT.......114K"><span id="translatedtitle">On the practical applications of atmosphere-ocean and atmosphere-wave coupling in <span class="hlt">mesoscale</span> numerical <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>Kochanski, Adam</p> <p></p> <p>The objectives of this work were to develop coupled atmosphere-ocean and atmosphere-wave <span class="hlt">models</span> for the verification of the atmospheric simulations, <span class="hlt">model</span> the small-scale ocean circulations, analyze the role of the atmospheric stability in the generation of coastal upwelling, improve the accuracy of numerical prediction over the coastal areas, and develop a parameterization of the swell-induced wind stress. The study confirmed the applicability of the high resolution <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> 5 (MM5) wind field prediction to driving small scale ocean <span class="hlt">models</span> applied to the U.S. West Coast, and showed that the small-scale circulation pattern of Bodega Bay can be well simulated even by the relatively simple 2D ocean <span class="hlt">model</span>. Additional experiments performed with the complex 3D Princeton Ocean <span class="hlt">Model</span> (POM) coupled with the MM5 showed the importance of the atmospheric stability in terms of the modification of the wind stress-curl pattern and the generation of coastal upwelling. The study revealed that the introduction of the stability effect to the wind stress computation may change the monthly mean wind stress curl by up to 0.15Pa/100km, and increase the simulated upwelling velocity by up to 25%, significantly improving the picture of the simulated upwelling and relaxation events. Further analysis performed with the MM5 <span class="hlt">model</span> run at 9km resolution, showed that the introduction of the atmosphere-ocean coupling greatly improved the quality of the <span class="hlt">model</span> results. The comparison with buoy data revealed that the atmosphere-ocean coupling led to a 95% increase in the correlation coefficients of the air temperature and heat fluxes, 23% for the wind direction, and up to 25% for the wind speed, and the reduction of the mean errors by up to 30%. The air-wave interaction <span class="hlt">model</span> developed during this study showed the applicability of the innovative semi-analytical approach to the computation of the swell-induced stress. Its results also confirmed the importance of the swell-induced stress for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PApGe.172.3455B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PApGe.172.3455B"><span id="translatedtitle">Parallel Implementation of Dispersive Tsunami Wave <span class="hlt">Modeling</span> with a <span class="hlt">Nesting</span> Algorithm for the 2011 Tohoku Tsunami</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baba, Toshitaka; Takahashi, Narumi; Kaneda, Yoshiyuki; Ando, Kazuto; Matsuoka, Daisuke; Kato, Toshihiro</p> <p>2015-12-01</p> <p>Because of improvements in offshore tsunami observation technology, dispersion phenomena during tsunami propagation have often been observed in recent tsunamis, for example the 2004 Indian Ocean and 2011 Tohoku tsunamis. The dispersive propagation of tsunamis can be simulated by use of the Boussinesq <span class="hlt">model</span>, but the <span class="hlt">model</span> demands many computational resources. However, rapid progress has been made in parallel computing technology. In this study, we investigated a parallelized approach for dispersive tsunami wave <span class="hlt">modeling</span>. Our new parallel software solves the nonlinear Boussinesq dispersive equations in spherical coordinates. A variable <span class="hlt">nested</span> algorithm was used to increase spatial resolution in the target region. The software can also be used to predict tsunami inundation on land. We used the dispersive tsunami <span class="hlt">model</span> to simulate the 2011 Tohoku earthquake on the Supercomputer K. Good agreement was apparent between the dispersive wave <span class="hlt">model</span> results and the tsunami waveforms observed offshore. The finest bathymetric grid interval was 2/9 arcsec (approx. 5 m) along longitude and latitude lines. Use of this grid simulated tsunami soliton fission near the Sendai coast. Incorporating the three-dimensional shape of buildings and structures led to improved <span class="hlt">modeling</span> of tsunami inundation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3724053','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3724053"><span id="translatedtitle">Understanding the transmission dynamics of respiratory syncytial virus using multiple time series and <span class="hlt">nested</span> <span class="hlt">models</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>White, L.J.; Mandl, J.N.; Gomes, M.G.M.; Bodley-Tickell, A.T.; Cane, P.A.; Perez-Brena, P.; Aguilar, J.C.; Siqueira, M.M.; Portes, S.A.; Straliotto, S.M.; Waris, M.; Nokes, D.J.; Medley, G.F.</p> <p>2007-01-01</p> <p>The nature and role of re-infection and partial immunity are likely to be important determinants of the transmission dynamics of human respiratory syncytial virus (hRSV). We propose a single <span class="hlt">model</span> structure that captures four possible host responses to infection and subsequent reinfection: partial susceptibility, altered infection duration, reduced infectiousness and temporary immunity (which might be partial). The magnitude of these responses is determined by four homotopy parameters, and by setting some of these parameters to extreme values we generate a set of eight <span class="hlt">nested</span>, deterministic transmission <span class="hlt">models</span>. In order to investigate hRSV transmission dynamics, we applied these <span class="hlt">models</span> to incidence data from eight international locations. Seasonality is included as cyclic variation in transmission. Parameters associated with the natural history of the infection were assumed to be independent of geographic location, while others, such as those associated with seasonality, were assumed location specific. <span class="hlt">Models</span> incorporating either of the two extreme assumptions for immunity (none or solid and lifelong) were unable to reproduce the observed dynamics. <span class="hlt">Model</span> fits with either waning or partial immunity to disease or both were visually comparable. The best fitting structure was a lifelong partial immunity to both disease and infection. Observed patterns were reproduced by stochastic simulations using the parameter values estimated from the deterministic <span class="hlt">models</span>. PMID:17335858</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Nests&pg=6&id=EJ666919','ERIC'); return false;" href="http://eric.ed.gov/?q=Nests&pg=6&id=EJ666919"><span id="translatedtitle">Triangular <span class="hlt">Nests</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>Powell, R. I.</p> <p>2002-01-01</p> <p>Shows how integer-sided triangles can be <span class="hlt">nested</span>, each <span class="hlt">nest</span> having a single enclosing isosceles triangle. Brings to light what can be seen as a relatively simple generalization of Pythagoras' theorem, a result that should be readily accessible to many secondary school pupils. (Author/KHR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMOS41C1243R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMOS41C1243R"><span id="translatedtitle">Interaction between <span class="hlt">Meso-scale</span> Eddies and Sub-polar Front in the East (Japan) Sea based on ARGO, AVHRR, and Numerical <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>Ro, Y.; Kim, E.</p> <p>2008-12-01</p> <p>The East (Japan) Sea is drawing keen international attentions from broad spectrum of groups such as scientists, diplomats, and defense officers for its geopolitical situation, peculiar scientific assets recognized as miniature ocean. From physical oceanographic aspect, it is very rich with many features such as basin-wide circulation pattern, boundary currents, sub-polar front, <span class="hlt">meso-scale</span> eddy activities and deep water formation. The circulation pattern in the East (Japan) Sea has been of major interests for its peculiar gyre, a western boundary current and its separation that resembles the currents such as Kuroshio and Gulf Stream. In relation to the gyre system in the East Sea, the formation of the East Korea Warm Current (EKWC) has brought up with many numerical experiments. Numerical experiments suggested a new idea to explain the formation of the EKWC in that the potential energy supply into the Ulleung Basin (UB) from the <span class="hlt">meso-scale</span> eddy is a key process. This is closely linked with the baroclinic instability and the meandering of offshore component of Tsushima Warm Current. The UB has drawn attentions for its role of the formation of two major boundary currents, EKWC, North Korea Warm Current (NKCC), their interaction with the <span class="hlt">mesoscale</span> UWE, watermass exchange between the Northern Japan Basin and UB. Numerical experiments along with hydrographic and other satellite datasets such as AVHRR, altimeter and ARGO profiles have been analyzed to understand the formation of the UWE. We found that the influence of the bottom topography and frictional forcing against lateral boundary are all closely associated with the sub-polar front. Meandering of the axis of the sub-polar front is closely linked with the separation point of the EKWC, Ulleung Warm Eddy, and other small and <span class="hlt">meso-scale</span> eddies on the sub-polar front. These will be demonstrated with results of the numerical <span class="hlt">modeling</span> experiments and animation movie will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120013630&hterms=kuo&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D50%26Ntt%3Dkuo','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120013630&hterms=kuo&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D50%26Ntt%3Dkuo"><span id="translatedtitle">Genesis of Twin Tropical Cyclones as Revealed by a Global <span class="hlt">Mesoscale</span> <span class="hlt">Model</span>: The Role of Mixed Rossby Gravity Waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shen, Bo-Wen; Tao, Wei-Kuo; Lin, Yuh-Lang; Laing, Arlene</p> <p>2012-01-01</p> <p>In this study, it is proposed that twin tropical cyclones (TCs), Kesiny and 01A, in May 2002 formed in association with the scale interactions of three gyres that appeared as a convectively-coupled mixed Rossby gravity (ccMRG) wave during an active phase of the Madden-Julian Oscillation (MJO). This is shown by analyzing observational data and performing simulations using a global <span class="hlt">mesoscale</span> <span class="hlt">model</span>. A 10-day control run is initialized at 0000 UTC 1 May 2002 with grid-scale condensation but no cumulus parameterizations. The ccMRG wave was identified as encompassing two developing and one non-developing gyres, the first two of which intensified and evolved into the twin TCs. The control run is able to reproduce the evolution of the ccMRG wave and the formation of the twin TCs about two and five days in advance as well as their subsequent intensity evolution and movement within an 8-10 day period. Five additional 10-day sensitivity experiments with different <span class="hlt">model</span> configurations are conducted to help understand the interaction of the three gyres. These experiments suggest the improved lead time in the control run may be attributed to the realistic simulation of the ccMRG wave with the following processes: (I) wave deepening associated with wave shortening and/or the intensification of individual gyres, (2) poleward movement of gyres that may be associated with bOlll1dary layer processes, (3) realistic simulation of moist processes at regional scales in association with each of the gyres, and (4) the vertical phasing of low- and mid-level cyclonic circulations associated with a specific gyre.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.1711G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.1711G"><span id="translatedtitle">Validation of regional precipitation-related indices dynamically downscaled from ERA-Interim Reanalysis Data by a <span class="hlt">Mesoscale</span> Atmospheric <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>Gan, T. Y.; Hanrahan, J.; Kuo, C. C.</p> <p>2012-04-01</p> <p>Extreme precipitation events in central Alberta have overwhelmed hydraulic structures several times in recent years, and it is expected that rainfall intensity in this region will continue to increase over the next several decades. Accurate rainfall projections, which are communicated in the form of Intensity-Duration-Frequency (IDF) curves, are thus needed to design sufficient municipal structures. Such data may be obtained through the use of Regional Climate <span class="hlt">Models</span> (RCMs), and one in particular, the fifth-generation NCAR/Penn State <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span> (MM5), is investigated here. MM5 is used to dynamically downscale ECMWF ERA-Interim reanalysis data to evaluate its ability to accurately simulate rainfall characteristics in central Alberta over two consecutive summers that represent contrasting precipitation regimes. Precipitation simulated at the local scale is verified with Edmonton's local rain gauge network, while larger-scale precipitation is compared with the High Resolution Precipitation Product (HRPP), CMORPH. This particular HRPP was compared with rain gauge data and radar images which revealed that it can be reliably used to validate MM5 output in this region. MM5 output is also compared to data from a local sounding station and other reanalysis variables. Precipitation data generated by MM5 revealed that this RCM can indeed distinguish between wet (2010) and dry (2009) years, but that simulated rainfall totals are too high during both precipitation regimes. This bias is attributed to enhanced moisture advection associated with large-scale flow anomalies, and should be taken into consideration when making projections regarding possible changes to future precipitation conditions in central Alberta.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DSRI...99...46L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DSRI...99...46L"><span id="translatedtitle">Three-dimensional properties of <span class="hlt">mesoscale</span> eddies in the South China Sea based on eddy-resolving <span class="hlt">model</span> output</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lin, Xiayan; Dong, Changming; Chen, Dake; Liu, Yu; Yang, Jingsong; Zou, Bin; Guan, Yuping</p> <p>2015-05-01</p> <p>Last decade has witnessed extensive studies on <span class="hlt">mesoscale</span> oceanic eddies in the Southern China Sea (SCS), however most of these studies are focused on the surface eddies, and three-dimensional features of eddies are not well known except some individual eddies. We apply a three-dimensional eddy detection scheme to a 9-year (2000-2008) eddy-resolving numerical solution to acquire three-dimensional eddy data set in the SCS. The <span class="hlt">model</span> solution is validated with observational data in terms of both seasonal and intra-seasonal scales. The statistical characteristics of eddies at the sea surface, such as eddy number, lifetime and radius, from the <span class="hlt">model</span> are comparable with those derived from the satellite altimetry data. The vertical profiles of the physical features of eddies are exposed from the statistical analysis of the three-dimensional eddy data set. For examples, more cyclonic eddies (CEs) are generated than anticyclonic eddies (AEs) in the depth above about 350 m and an opposite trend is presented below 350 m. The lifetimes of CEs and AEs are statistically equal and no significant variation at different vertical levels. Eddies in the central SCS have the largest size than in other areas and their sizes decrease with the increase in water depth. The relative vorticity amplitude of eddies decreases with the increase in the depth. There are three different types of eddies: bowl-shaped with the largest size at the surface, lens-shaped with the largest size in the middle and cone-shaped with the largest size at the bottom. Most of eddies are bowl-shaped eddies. The three types of eddies have different effects on the temperature and salinity profiles. Eddy genesis mechanisms are discussed and categorized into three types in the SCS: surface wind curl input, current interaction with the bottom topography and Kuroshio intrusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010321','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010321"><span id="translatedtitle">Genesis of Twin Tropical Cyclones as Revealed by a Global <span class="hlt">Mesoscale</span> <span class="hlt">Model</span>: The Role of Mixed Rossby Gravity Waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shen, Bo-Wen; Tao, Wei-Kuo; Lin, Yuh-Lang; Laing, Arlene</p> <p>2012-01-01</p> <p>In this study, it is proposed that twin tropical cyclones (TCs), Kesiny and 01A, in May 2002 formed in association with the scale interactions of three gyres that appeared as a convectively coupled mixed Rossby gravity (ccMRG) wave during an active phase of the Madden-Julian Oscillation (MJO). This is shown by analyzing observational data, including NCEP reanalysis data and METEOSAT 7 IR satellite imagery, and performing numerical simulations using a global <span class="hlt">mesoscale</span> <span class="hlt">model</span>. A 10-day control run is initialized at 0000 UTC 1 May 2002 with grid-scale condensation but no sub-grid cumulus parameterizations. The ccMRG wave was identified as encompassing two developing and one non-developing gyres, the first two of which intensified and evolved into the twin TCs. The control run is able to reproduce the evolution of the ccMRG wave and thus the formation of the twin TCs about two and five days in advance as well as their subsequent intensity evolution and movement within an 8-10 day period. Five additional 10-day sensitivity experiments with different <span class="hlt">model</span> configurations are conducted to help understand the interaction of the three gyres, leading to the formation of the TCs. These experiments suggest the improved lead time in the control run may be attributed to the realistic simulation of the ccMRG wave with the following processes: (1) wave deepening (intensification) associated with a reduction in wavelength and/or the intensification of individual gyres, (2) poleward movement of gyres that may be associated with boundary layer processes, (3) realistic simulation of moist processes at regional scales in association with each of the gyres, and (4) the vertical phasing of low- and mid-level cyclonic circulations associated with a specific gyre.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA631047','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA631047"><span id="translatedtitle">Implementation and Research on the Operational Use of the <span class="hlt">Mesoscale</span> Prediction <span class="hlt">Model</span> COAMPS in Poland</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2016-06-07</p> <p>Centre for Mathematical and Computational <span class="hlt">Modelling</span>, Warsaw University, Pawinskiego 5A, 02-106 Warsaw, Poland phone: +48-22-554-0816 fax: +48-22-554...Faculty of Mathematics , Informatics and Applied Mathematics phone: +48-22-554-4214 fax: +48-22-554-0801 email: HTokapala@icm.edu.plT Leszek Herman... Mathematical and Computational <span class="hlt">Modelling</span> (ICM), Warsaw University; (b) validate COAMPS <span class="hlt">model</span> performance through inter-comparisons with statistics</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040171259','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040171259"><span id="translatedtitle">High-Resolution <span class="hlt">Mesoscale</span> Simulations of the 6-7 May 2000 Missouri Flash Flood: Impact of <span class="hlt">Model</span> Initialization and Land Surface Treatment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Baker, R. David; Wang, Yansen; Tao, Wei-Kuo; Wetzel, Peter; Belcher, Larry R.</p> <p>2004-01-01</p> <p>High-resolution <span class="hlt">mesoscale</span> <span class="hlt">model</span> simulations of the 6-7 May 2000 Missouri flash flood event were performed to test the impact of <span class="hlt">model</span> initialization and land surface treatment on timing, intensity, and location of extreme precipitation. In this flash flood event, a <span class="hlt">mesoscale</span> convective system (MCS) produced over 340 mm of rain in roughly 9 hours in some locations. Two different types of <span class="hlt">model</span> initialization were employed: 1) NCEP global reanalysis with 2.5-degree grid spacing and 12-hour temporal resolution, and 2) Eta reanalysis with 40- km grid spacing and $hour temporal resolution. In addition, two different land surface treatments were considered. A simple land scheme. (SLAB) keeps soil moisture fixed at initial values throughout the simulation, while a more sophisticated land <span class="hlt">model</span> (PLACE) allows for r interactive feedback. Simulations with high-resolution Eta <span class="hlt">model</span> initialization show considerable improvement in the intensity of precipitation due to the presence in the initialization of a residual <span class="hlt">mesoscale</span> convective vortex (hlCV) from a previous MCS. Simulations with the PLACE land <span class="hlt">model</span> show improved location of heavy precipitation. Since soil moisture can vary over time in the PLACE <span class="hlt">model</span>, surface energy fluxes exhibit strong spatial gradients. These surface energy flux gradients help produce a strong low-level jet (LLJ) in the correct location. The LLJ then interacts with the cold outflow boundary of the MCS to produce new convective cells. The simulation with both high-resolution <span class="hlt">model</span> initialization and time-varying soil moisture test reproduces the intensity and location of observed rainfall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003HESS....7..812K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003HESS....7..812K"><span id="translatedtitle">Precipitation forecasting by a <span class="hlt">mesoscale</span> numerical weather prediction (NWP) <span class="hlt">model</span>: eight years of experience</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaufmann, P.; Schubiger, F.; Binder, P.</p> <p></p> <p>The Swiss <span class="hlt">Model</span>, a hydrostatic numerical weather prediction <span class="hlt">model</span>, has been used at MeteoSwiss for operational forecasting at the meso-beta scale (mesh-size 14 km) from 1994 until 2001. The quality of the quantitative precipitation forecasts is evaluated for the eight years of operation. The seasonal precipitation over Switzerland and its dependence on altitude is examined for both <span class="hlt">model</span> forecasts and observations using the Swiss rain gauge network sampling daily precipitation at over 400 stations for verification. The mean diurnal cycle of precipitation is verified against the automatic surface observation network on the basis of hourly recordings. In winter, there is no diurnal forcing of precipitation and the <span class="hlt">modelled</span> precipitation agrees with the observed values. In summer, the convection in the <span class="hlt">model</span> starts too early, overestimates the amount of precipitation and is too short-lived. Skill scores calculated for six-hourly precipitation sums show a constant level of performance over the <span class="hlt">model</span> life cycle. Dry and wet seasons influence the <span class="hlt">model</span> performance more than the <span class="hlt">model</span> changes during its operational period. The comprehensive verification of the <span class="hlt">model</span> precipitation is complemented by the discussion of a number of heavy rain events investigated during the RAPHAEL project. The sensitivities to a number of <span class="hlt">model</span> components are illustrated, namely the driving boundary fields, the internal partitioning of parameterised and grid-scale precipitation, the advection scheme and the vertical resolution. While a small impact of the advection scheme had to be expected, the increasing overprediction of rain with increasing vertical resolution in the RAPHAEL case studies was larger than previously thought. The frequent update of the boundary conditions enhances the positioning of the rain in the <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.2810S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.2810S"><span id="translatedtitle">Hydrological and hydraulic results of an integrated <span class="hlt">modelling</span> approach in a <span class="hlt">mesoscale</span> Chinese catchment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schmalz, B.; Strehmel, A.; Song, S.; Kuemmerlen, M.; Cai, Q.; Jähnig, S.; Fohrer, N.</p> <p>2012-04-01</p> <p>Catchment properties, in-stream processes and their effects on aquatic organisms are closely linked. For the assessment of key driving forces, pressures on an ecosystem, the habitat state and the effect of climate or land use changes on a habitat, DPSI (Driver-Pressure-State-Impact) approaches are used. The aim of our DFG-/NSFC project is the development of an integrated <span class="hlt">modelling</span> approach to depict the impact of environmental changes on aquatic ecosystems in the Changjiang catchment of the Poyang lake area in China. We create a dynamic DPSI-system, integrating the <span class="hlt">models</span> SWAT (catchment processes), HEC-RAS (in-stream processes) and BIOMOD (biological responses). The ecohydrological <span class="hlt">model</span> SWAT simulates the water and nutrient balances of the entire catchment. The SWAT results as discharge and sediment are transferred to the hydraulic <span class="hlt">model</span> HEC-RAS. HEC-RAS calculates in-stream parameters as flow velocity, water depths, shear stress, etc. for cross sections at selected river sections. Afterwards, both <span class="hlt">models</span> transfer their results to the species distribution <span class="hlt">model</span> BIOMOD, which calculates the habitat functions and occurrence probabilities for each selected species (benthic macroinvertebrates). The developed concept, the procedure of the field campaigns and the first steps and results of the ecohydrological and hydraulic <span class="hlt">modeling</span> are presented. Catchment discharge time series of the SWAT <span class="hlt">model</span> were used as boundary conditions to the hydraulic <span class="hlt">modelling</span>. The HEC-RAS <span class="hlt">models</span> were set up for ten river sections with a length of about 300 meters each. The calibration of the HEC-RAS stream flow <span class="hlt">models</span> was carried out towards the elevation differences between adjacent cross-sections, rather than roughness values. In a sensitivity analysis this approach proved to yield very good calibration results. Among other parameters, the stream flow variables water depth, flow velocity, shear stress and stream power were calculated and analysed. The HEC-RAS <span class="hlt">model</span> results showed that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040034130','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040034130"><span id="translatedtitle">A Stochastic <span class="hlt">Model</span> of Space-Time Variability of <span class="hlt">Mesoscale</span> Rainfall: Statistics of Spatial Averages</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kundu, Prasun K.; Bell, Thomas L.</p> <p>2003-01-01</p> <p>A characteristic feature of rainfall statistics is that they depend on the space and time scales over which rain data are averaged. A previously developed spectral <span class="hlt">model</span> of rain statistics that is designed to capture this property, predicts power law scaling behavior for the second moment statistics of area-averaged rain rate on the averaging length scale L as L right arrow 0. In the present work a more efficient method of estimating the <span class="hlt">model</span> parameters is presented, and used to fit the <span class="hlt">model</span> to the statistics of area-averaged rain rate derived from gridded radar precipitation data from TOGA COARE. Statistical properties of the data and the <span class="hlt">model</span> predictions are compared over a wide range of averaging scales. An extension of the spectral <span class="hlt">model</span> scaling relations to describe the dependence of the average fraction of grid boxes within an area containing nonzero rain (the "rainy area fraction") on the grid scale L is also explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA597774','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA597774"><span id="translatedtitle">New Approaches to the Parameterization of Gravity-Wave and Flow-Blocking Drag due to Unresolved <span class="hlt">Mesoscale</span> Orography Guided by <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> Predictability Research</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2013-09-30</p> <p>red curves reveal a substantial cold bias in the analyzed NAVGEM stratospheric temperatures in boreal winter, when the Sun disappears at high...mean poleward and downwelling circulation cell that adiabatically warms the stratosphere . The black curves in Figure 6 show the results from a...NAVGEM prediction skill in the upper stratosphere . 10 Figure 7. Zonal-mean temperature increments versus NAVGEM <span class="hlt">model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRD..112.4106C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRD..112.4106C"><span id="translatedtitle">Seasonal rainfall predictions over the southeast United States using the Florida State University <span class="hlt">nested</span> regional spectral <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>Cocke, Steven; Larow, T. E.; Shin, D. W.</p> <p>2007-02-01</p> <p>Seasonal rainfall predictions over the southeast United States using the recently developed Florida State University (FSU) <span class="hlt">nested</span> regional spectral <span class="hlt">model</span> are presented. The regional <span class="hlt">model</span> is <span class="hlt">nested</span> within the FSU coupled <span class="hlt">model</span>, which includes a version of the Max Plank Institute Hamburg Ocean Primitive Equation <span class="hlt">model</span>. The southeast U.S. winter has a rather strong climatic signal due to teleconnections with tropical Pacific sea surface temperatures and thus provides a good test case scenario for a <span class="hlt">modeling</span> study. Simulations were done for 12 boreal winter seasons, from 1986 to 1997. Both the regional and global <span class="hlt">models</span> captured the basic large-scale patterns of precipitation reasonably well when compared to observed station data. The regional <span class="hlt">model</span> was able to predict the anomaly pattern somewhat better than the global <span class="hlt">model</span>. The regional <span class="hlt">model</span> was particularly more skillful at predicting the frequency of significant rainfall events, in part because of the ability to produce heavier rainfall events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006SPIE.6404E..0KS','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006SPIE.6404E..0KS"><span id="translatedtitle">Improvements in simulation of atmospheric boundary layer parameters through data assimilation in ARPS <span class="hlt">mesoscale</span> atmospheric <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>Subrahamanyam, D. Bala; Ramachandran, Radhika; Kunhikrishnan, P. K.</p> <p>2006-12-01</p> <p>In a broad sense, 'Data Assimilation' refers to a technique, whereby the realistic observational datasets are injected to a <span class="hlt">model</span> simulation for bringing accurate forecasts. There are several schemes available for insertion of observational datasets in the <span class="hlt">model</span>. In this piece of research, we present one of the simplest, yet powerful data assimilation techniques - known as nudging through optimal interpolation in the ARPS (Advanced Regional Prediction System) <span class="hlt">model</span>. Through this technique, we firstly identify the assimilation window in space and time over which the observational datasets need to be inserted and the <span class="hlt">model</span> products require to be adjusted. Appropriate <span class="hlt">model</span> variables are then adjusted for the realistic observational datasets with a proper weightage being given to the observations. Incorporation of such a subroutine in the <span class="hlt">model</span> that takes care of the assimilation in the <span class="hlt">model</span> provides a powerful tool for improving the forecast parameters. Such a technique can be very useful in cases, where observational datasets are available at regular intervals. In this article, we demonstrate the effectiveness of this technique for simulation of profiles of Atmospheric Boundary Layer parameters for a tiny island of Kaashidhoo in the Republic of Maldives, where regular GPS Loran Atmospheric Soundings were carried out during the Intensive Field Phase of Indian Ocean Experiment (INDOEX, IFP-99).</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('http://www.osti.gov/scitech/servlets/purl/1211581','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1211581"><span id="translatedtitle"><span class="hlt">Modeling</span> Hot-Spot Contributions in Shocked High Explosives at the <span class="hlt">Mesoscale</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Harrier, Danielle</p> <p>2015-08-12</p> <p>When looking at performance of high explosives, the defects within the explosive become very important. Plastic bonded explosives, or PBXs, contain voids of air and bonder between the particles of explosive material that aid in the ignition of the explosive. These voids collapse in high pressure shock conditions, which leads to the formation of hot spots. Hot spots are localized high temperature and high pressure regions that cause significant changes in the way the explosive material detonates. Previously hot spots have been overlooked with <span class="hlt">modeling</span>, but now scientists are realizing their importance and new <span class="hlt">modeling</span> systems that can accurately <span class="hlt">model</span> hot spots are underway.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24077621','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24077621"><span id="translatedtitle">Efficient analysis of Q-level <span class="hlt">nested</span> hierarchical general linear <span class="hlt">models</span> given ignorable missing data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shin, Yongyun; Raudenbush, Stephen W</p> <p>2013-09-28</p> <p>This article extends single-level missing data methods to efficient estimation of a Q-level <span class="hlt">nested</span> hierarchical general linear <span class="hlt">model</span> given ignorable missing data with a general missing pattern at any of the Q levels. The key idea is to reexpress a desired hierarchical <span class="hlt">model</span> as the joint distribution of all variables including the outcome that are subject to missingness, conditional on all of the covariates that are completely observed and to estimate the joint <span class="hlt">model</span> under normal theory. The unconstrained joint <span class="hlt">model</span>, however, identifies extraneous parameters that are not of interest in subsequent analysis of the hierarchical <span class="hlt">model</span> and that rapidly multiply as the number of levels, the number of variables subject to missingness, and the number of random coefficients grow. Therefore, the joint <span class="hlt">model</span> may be extremely high dimensional and difficult to estimate well unless constraints are imposed to avoid the proliferation of extraneous covariance components at each level. Furthermore, the over-identified hierarchical <span class="hlt">model</span> may produce considerably biased inferences. The challenge is to represent the constraints within the framework of the Q-level <span class="hlt">model</span> in a way that is uniform without regard to Q; in a way that facilitates efficient computation for any number of Q levels; and also in a way that produces unbiased and efficient analysis of the hierarchical <span class="hlt">model</span>. Our approach yields Q-step recursive estimation and imputation procedures whose qth-step computation involves only level-q data given higher-level computation components. We illustrate the approach with a study of the growth in body mass index analyzing a national sample of elementary school children.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992PhDT.......123H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992PhDT.......123H"><span id="translatedtitle">Four-Dimensional Data Assimilation of Gale Data Using a Multivariate Analysis Scheme and a <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> with Diabatic Initialization.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harms, Dewey Elvin</p> <p>1992-01-01</p> <p>A method of assimilating 3-hourly sounding data is developed and successfully tested in this study. First, the successive corrections scheme of Bratseth (1986), which converges to optimum interpolation, is applied for the numerical analysis of data collected during the Genesis of Atlantic Lows Experiment (GALE). Univariate analyses of the mass and wind field are produced. The coupling of the mass and wind field is achieved by further iterations of the geopotential utilizing improving estimates of the geostrophic wind to extrapolate the geopotential to the grid points. The univariate wind analysis is then corrected for the new geostrophic wind. Next, diabatic forcing is incorporated into a vertical mode initialization scheme to provide more realistic initial conditions and to shorten the spinup time of the Naval Research Laboratory/North Carolina State University (NRL/NCSU) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. Latent-heating profiles are computed from 'spun-up' <span class="hlt">model</span>-generated and observed rainfall. The latent heating is distributed in the vertical according to the cumulus convective parameterization scheme (Kuo scheme) of the <span class="hlt">model</span>. Compatibility between the specified heating during initialization and the heating during early <span class="hlt">model</span> integration is retained by merging the <span class="hlt">model</span> integrated rainfall and heating rates with those rates from the initialization. Finally, the multivariate, successive correction analysis scheme and the diabatic initialization procedure are combined with the NRL/NCSU <span class="hlt">model</span> to form an intermittent data-assimilation system. Assimilations of the GALE data over a 2{1over2}-day period were performed with differing update cycles of 3, 6, and 12 h. Twelve-hour NMC hemispheric analyses served as the "no assimilation" control case for comparison. The assimilation of 3-hourly GALE data led to large decreases in background forecast rms errors and smaller decreases in analysis rms error. Better consistency in time was achieved between forecasts and analyses in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA595187','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA595187"><span id="translatedtitle">Mitigating Excessive Drying From the Use of Observations in <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2014-01-01</p> <p>microphysics parameterization (Hong et al., 2004; Hong and Lim, 2006) is utilized and the Kain-Fritsch cumulus parameterization (Kain, 2004) is utilized on... cloud water by 13 UTC in the non-nudging experiment in the vicinity of San Diego indicates that the physical tendency terms are working to increase the...decrease as rapidly with time. Just to the west of San Diego, the <span class="hlt">model</span> does not form clouds by 13 UTC, suggesting that the <span class="hlt">model</span> may be less resistant to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990072355&hterms=statistics+web&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dstatistics%2Bweb','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990072355&hterms=statistics+web&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dstatistics%2Bweb"><span id="translatedtitle">Real-Time Assimilation of Goes-Derived Products into A <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> and It's Impact on Short-Term (06-36hr) Forecasts from 17 October 1998 through the Present</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lapenta, William M.; Suggs, Ron; Jedlovec, Gary; McNider, Richard T.</p> <p>1999-01-01</p> <p>As the parameterizations of surface energy budgets in regional <span class="hlt">models</span> have become more complete physically, <span class="hlt">models</span> have the potential to be much more realistic in simulations of coupling between surface radiation, hydrology, and surface energy transfer. Realizing the importance of properly specifying the surface energy budget, many institutions are using land-surface <span class="hlt">models</span> to represent the lower boundary forcing associated with biophysical processes and soil hydrology. However, the added degrees of freedom due to inclusion of such land-surface schemes require the specification of additional parameters within the <span class="hlt">model</span> system such as vegetative resistances, green vegetation fraction, leaf area index, soil physical and hydraulic characteristics, stream flow, runoff, and the vertical distribution of soil moisture. Spatial heterogeneity of these parameters makes correct specification problematic since measurements are not routinely available. A technique has been developed for assimilating GOES-IR skin temperature tendencies, solar insolation, and surface albedo into the surface energy budget equation of a <span class="hlt">mesoscale</span> <span class="hlt">model</span> so that the simulated rate of temperature change closely agrees with the satellite observations. The technique has been successfully employed in a number of <span class="hlt">mesoscale</span> <span class="hlt">models</span> in case-study mode. We have taken the next step and developed a study to determine if assimilating these types of data into <span class="hlt">mesoscale</span> <span class="hlt">models</span> in real-time can improve short-term (648h) forecasts of temperature, relative humidity, and QPF on a daily basis over relatively large regions. Therefore, an operational <span class="hlt">modeling</span>/assimilation system has been developed at the GHCC during the past summer that allows us to produce simulations out to 48 hours in a timely manor. The PSU/NCAR MM5 is used in a <span class="hlt">nested</span> configuration with a 25 km grid covering the southeastern third of the US. The <span class="hlt">model</span> has been on-line since 1 July 1998 and forecast products are posted on our web site. The satellite</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ACP....1612099J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ACP....1612099J"><span id="translatedtitle"><span class="hlt">Modeling</span> the reactive halogen plume from Ambrym and its impact on the troposphere with the CCATT-BRAMS <span class="hlt">mesoscale</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>Jourdain, Line; Roberts, Tjarda Jane; Pirre, Michel; Josse, Beatrice</p> <p>2016-09-01</p> <p>Ambrym Volcano (Vanuatu, southwest Pacific) is one of the largest sources of continuous volcanic emissions worldwide. As well as releasing SO2 that is oxidized to sulfate, volcanic plumes in the troposphere are shown to undergo reactive halogen chemistry whose atmospheric impacts have been little explored to date. Here, we investigate with the regional-scale <span class="hlt">model</span> CCATT-BRAMS (Coupled Chemistry Aerosol-Tracer Transport <span class="hlt">model</span>, Brazilian developments on the Regional Atmospheric <span class="hlt">Modeling</span> System, version 4.3) the chemical processing in the Ambrym plume and the impact of this volcano on the atmospheric chemistry on both local and regional scales. We focus on an episode of extreme passive degassing that occurred in early 2005 and for which airborne DOAS (differential optical absorption spectroscopy) measurements of SO2 and BrO columns in the near-downwind plume between 15 and 40 km from the vents have been reported. The <span class="hlt">model</span> was developed to include reactive halogen chemistry and a volcanic emission source specific to this extreme degassing event. In order to test our understanding of the volcanic plume chemistry, we performed very high-resolution (500 m × 500 m) simulations using the <span class="hlt">model</span> <span class="hlt">nesting</span> grid capability and compared each DOAS measurement to its temporally and spatially interpolated <span class="hlt">model</span> counterpart "point-by-point". Simulated SO2 columns show very good quantitative agreement with the DOAS observations, suggesting that the plume direction as well as its dilution in the near-downwind plume are well captured. The <span class="hlt">model</span> also reproduces the salient features of volcanic chemistry as reported in previous work, such as HOx and ozone depletion in the core of the plume. When a high-temperature chemistry initialization is included, the <span class="hlt">model</span> is able to capture the observed BrO / SO2 trend with distance from the vent. The main discrepancy between observations and <span class="hlt">model</span> is the bias between the magnitudes of observed and simulated BrO columns that ranges from 60</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......233L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......233L"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> of strain induced solid state amorphization in crystalline materials</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lei, Lei</p> <p></p> <p>Solid state amorphization, and in particular crystalline to amorphous transformation, can be observed in metallic alloys, semiconductors, intermetallics, minerals, and also molecular crystals when they undergo irradiation, hydrogen gas dissolution, thermal interdiffusion, mechanical alloying, or mechanical milling. Although the amorphization mechanisms may be different, the transformation occurs due to the high level of disorder introduced into the material. Milling induced solid state amorphization is proposed to be the result of accumulation of crystal defects, specifically dislocations, as the material is subjected to large deformations during the high energy process. Thus, understanding the deformation mechanisms of crystalline materials will be the first step in studying solid state amorphization in crystalline materials, which not only has scientific contributions, but also technical consequences. A phase field dislocation dynamics (PFDD) approach is employed in this work to simulate plastic deformation of molecular crystals. This PFDD <span class="hlt">model</span> has the advantage of tracking all of the dislocations in a material simultaneously. The <span class="hlt">model</span> takes into account the elastic interaction between dislocations, the lattice resistance to dislocation motion, and the elastic interaction of dislocations with an external stress field. The PFDD <span class="hlt">model</span> is employed to describe the deformation of molecular crystals with pharmaceutical applications, namely, single crystal sucrose, acetaminophen, gamma-indomethacin, and aspirin. Stress-strain curves are produced that result in expected anisotropic material response due to the activation of different slip systems and yield stresses that agree well with those from experiments. The PFDD <span class="hlt">model</span> is coupled to a phase transformation <span class="hlt">model</span> to study the relation between plastic deformation and the solid state amorphization of crystals that undergo milling. This <span class="hlt">model</span> predicts the amorphous volume fraction in excellent agreement with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070016641&hterms=Hurricane+Katrina&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BKatrina','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070016641&hterms=Hurricane+Katrina&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BKatrina"><span id="translatedtitle">Hurricane Intensity Forecasts with a Global <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> on the NASA Columbia Supercomputer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shen, Bo-Wen; Tao, Wei-Kuo; Atlas, Robert</p> <p>2006-01-01</p> <p>It is known that General Circulation <span class="hlt">Models</span> (GCMs) have insufficient resolution to accurately simulate hurricane near-eye structure and intensity. The increasing capabilities of high-end computers (e.g., the NASA Columbia Supercomputer) have changed this. In 2004, the finite-volume General Circulation <span class="hlt">Model</span> at a 1/4 degree resolution, doubling the resolution used by most of operational NWP center at that time, was implemented and run to obtain promising landfall predictions for major hurricanes (e.g., Charley, Frances, Ivan, and Jeanne). In 2005, we have successfully implemented the 1/8 degree version, and demonstrated its performance on intensity forecasts with hurricane Katrina (2005). It is found that the 1/8 degree <span class="hlt">model</span> is capable of simulating the radius of maximum wind and near-eye wind structure, and thereby promising intensity forecasts. In this study, we will further evaluate the <span class="hlt">model</span> s performance on intensity forecasts of hurricanes Ivan, Jeanne, Karl in 2004. Suggestions for further <span class="hlt">model</span> development will be made in the end.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5591130','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5591130"><span id="translatedtitle">MESOI Version 2. 0: an interactive <span class="hlt">mesoscale</span> Lagrangian puff dispersion <span class="hlt">model</span> with deposition and decay</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ramsdell, J.V.; Athey, G.F.; Glantz, C.S.</p> <p>1983-11-01</p> <p>MESOI Version 2.0 is an interactive Lagrangian puff <span class="hlt">model</span> for estimating the transport, diffusion, deposition and decay of effluents released to the atmosphere. The <span class="hlt">model</span> is capable of treating simultaneous releases from as many as four release points, which may be elevated or at ground-level. The puffs are advected by a horizontal wind field that is defined in three dimensions. The wind field may be adjusted for expected topographic effects. The concentration distribution within the puffs is initially assumed to be Gaussian in the horizontal and vertical. However, the vertical concentration distribution is modified by assuming reflection at the ground and the top of the atmospheric mixing layer. Material is deposited on the surface using a source depletion, dry deposition <span class="hlt">model</span> and a washout coefficient <span class="hlt">model</span>. The <span class="hlt">model</span> also treats the decay of a primary effluent species and the ingrowth and decay of a single daughter species using a first order decay process. This report is divided into two parts. The first part discusses the theoretical and mathematical bases upon which MESOI Version 2.0 is based. The second part contains the MESOI computer code. The programs were written in the ANSI standard FORTRAN 77 and were developed on a VAX 11/780 computer. 43 references, 14 figures, 13 tables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.A13E0986S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.A13E0986S"><span id="translatedtitle">Hurricane Intensity Forecasts with a Global <span class="hlt">Mesoscale</span> <span class="hlt">Model</span> on the NASA Columbia Supercomputer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, B.; Tao, W.; Atlas, R.</p> <p>2006-12-01</p> <p>It is known that General Circulation <span class="hlt">Models</span> (GCMs) have insufficient resolution to accurately simulate hurricane near-eye structure and intensity. The increasing capabilities of high-end computers (e.g., the NASA Columbia Supercomputer) have changed this. In 2004, the finite-volume General Circulation <span class="hlt">Model</span> at a 1/4 degree resolution, doubling the resolution used by most of operational NWP center at that time, was implemented and run to obtain promising landfall predictions for major hurricanes (e.g., Charley, Frances, Ivan, and Jeanne). In 2005, we have successfully implemented the 1/8 degree version, and demonstrated its performance on intensity forecasts with hurricane Katrina (2005). It is found that the 1/8 degree <span class="hlt">model</span> is capable of simulating the radius of maximum wind and near-eye wind structure, and thereby promising intensity forecasts. In this study, we will further evaluate the <span class="hlt">model</span>'s performance on intensity forecasts of hurricanes Ivan, Jeanne, Karl in 2004. Suggestions for further <span class="hlt">model</span> development will be made in the end.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApPhA.122..890C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApPhA.122..890C"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> and simulation of microstructure evolution during dynamic recrystallization of a Ni-based superalloy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Fei; Cui, Zhenshan; Ou, Hengan; Long, Hui</p> <p>2016-10-01</p> <p>Microstructural evolution and plastic flow characteristics of a Ni-based superalloy were investigated using a simulative <span class="hlt">model</span> that couples the basic metallurgical principle of dynamic recrystallization (DRX) with the two-dimensional (2D) cellular automaton (CA). Variation of dislocation density with local strain of deformation is considered for accurate determination of the microstructural evolution during DRX. The grain topography, the grain size and the recrystallized fraction can be well predicted by using the developed CA <span class="hlt">model</span>, which enables to the establishment of the relationship between the flow stress, dislocation density, recrystallized fraction volume, recrystallized grain size and the thermomechanical parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRD..11623104Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRD..11623104Z"><span id="translatedtitle">Genesis of Typhoon Nari (2001) from a <span class="hlt">mesoscale</span> convective system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Da-Lin; Tian, Liqing; Yang, Ming-Jen</p> <p>2011-12-01</p> <p>In this study, the origin and genesis of Typhoon Nari (2001) as well as its erratic looping track, are examined using large-scale analysis, satellite observations, and a 4 day <span class="hlt">nested</span>, cloud-resolving simulation with the finest grid size of 1.33 km. Observational analysis reveals that Nari could be traced 5 days back to a diurnally varying <span class="hlt">mesoscale</span> convective system with growing cyclonic vorticity and relative humidity in the lower troposphere and that it evolved from a <span class="hlt">mesoscale</span> convective vortex (MCV) as moving over a warm ocean under the influence of a subtropical high, a weak westerly baroclinic disturbance, an approaching-and-departing Typhoon Danas to the east, and the Kuroshio Current. Results show that the <span class="hlt">model</span> reproduces the genesis, final intensity, looping track, and the general convective activity of Nari during the 4 day period. It also captures two deep subvortices at the eye-eyewall interface that are similar to those previously observed, a few spiral rainbands, and a midget storm size associated with Nari's relatively dry and stable environment. We find that (1) continuous convective overturning within the MCV stretches the low-level vorticity and moistens a deep <span class="hlt">mesoscale</span> column that are both favorable for genesis; (2) Nari's genesis does not occur until after the passage of the baroclinic disturbance; (3) convective asymmetry induces a smaller-sized vortex circulation from the preexisting MCV; (4) the vortex-vortex interaction with Danas leads to Nari's looping track and temporal weakening; and (5) midlevel convergence associated with the subtropical high and Danas accounts for the generation of a nearly upright eyewall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1022908','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1022908"><span id="translatedtitle"><span class="hlt">MESOSCALE</span> <span class="hlt">MODELING</span> OF DEFLAGRATION-INDUCED DECONSOLIDATION IN POLYMER-BONDED EXPLOSIVES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Springer, H K; Glascoe, E A; Reaugh, J E; Kercher, J R; Maienschein, J L</p> <p>2011-08-01</p> <p>Initially undamaged polymer-bonded explosives can transition from conductive burning to more violent convective burning via rapid deconsolidation at higher pressures. The pressure-dependent infiltration of cracks and pores, i.e., damage, by product gases at the burn-front is a key step in the transition to convective burning. However, the relative influence of pre-existing damage and the evolution of deflagration-induced damage during the transition to convective burning is not well understood. The objective of this study is to investigate the role of microstructure and initial pressurization on deconsolidation. We performed simulations using the multi-physics hydrocode, ALE3D. HMX-Viton A served as our <span class="hlt">model</span> explosive. A Prout-Tompkins chemical kinetic <span class="hlt">model</span>, Vielle's Law pressure-dependent burning, Gruneisen equation-of-state, and simplified strength <span class="hlt">model</span> were used for the HMX. The propensity for deconsolidation increased with increasing defect size and decreasing initial pressurization, as measured by the increase in burning surface area. These studies are important because they enable the development of continuum-scale damage <span class="hlt">models</span> and the design of inherently safer explosives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA567900','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA567900"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> of Nonlinear Elasticity and Fracture in Ceramic Polycrystals Under Dynamic Shear and Compression</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2012-08-01</p> <p>investigation of heterogeneous microplasticity in ceramics deformed under high confining stresses. Mech. Mater. 37, 95–112. Zhang, K., Wu, M., Feng, R., 2005b...Simulation of microplasticity -induced deformation in uniaxially strained ceramics by 3-D Voronoi polycrystal <span class="hlt">modeling</span>. Int. J. Plasticity 21, 801–834</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/985829','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/985829"><span id="translatedtitle">THE SIMULATION OF FINE SCALE NOCTURNAL BOUNDARY LAYER MOTIONS WITH A <span class="hlt">MESO-SCALE</span> ATMOSPHERIC <span class="hlt">MODEL</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Werth, D.; Kurzeja, R.; Parker, M.</p> <p>2009-04-02</p> <p>A field project over the Atmospheric Radiation Measurement-Clouds and Radiation Testbed (ARM-CART) site during a period of several nights in September, 2007 was conducted to explore the evolution of the low-level jet (LLJ). Data was collected from a tower and a sodar and analyzed for turbulent behavior. To study the full range of nocturnal boundary layer (NBL) behavior, the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS) was used to simulate the ARM-CART NBL field experiment and validated against the data collected from the site. This <span class="hlt">model</span> was run at high resolution, and is ideal for calculating the interactions among the various motions within the boundary layer and their influence on the surface. The <span class="hlt">model</span> reproduces adequately the synoptic situation and the formation and dissolution cycles of the low-level jet, although it suffers from insufficient cloud production and excessive nocturnal cooling. The authors suggest that observed heat flux data may further improve the realism of the simulations both in the cloud formation and in the jet characteristics. In a higher resolution simulation, the NBL experiences motion on a range of timescales as revealed by a wavelet analysis, and these are affected by the presence of the LLJ. The <span class="hlt">model</span> can therefore be used to provide information on activity throughout the depth of the NBL.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2832035','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2832035"><span id="translatedtitle">Using stochastic <span class="hlt">models</span> calibrated from nanosecond nonequilibrium simulations to approximate <span class="hlt">mesoscale</span> information</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Calderon, Christopher P.; Janosi, Lorant; Kosztin, Ioan</p> <p>2009-01-01</p> <p>We demonstrate how the surrogate process approximation (SPA) method can be used to compute both the potential of mean force along a reaction coordinate and the associated diffusion coefficient using a relatively small number (10–20) of bidirectional nonequilibrium trajectories coming from a complex system. Our method provides confidence bands which take the variability of the initial configuration of the high-dimensional system, continuous nature of the work paths, and thermal fluctuations into account. Maximum-likelihood-type methods are used to estimate a stochastic differential equation (SDE) approximating the dynamics. For each observed time series, we estimate a new SDE resulting in a collection of SPA <span class="hlt">models</span>. The physical significance of the collection of SPA <span class="hlt">models</span> is discussed and methods for exploiting information in the population of estimated SPA <span class="hlt">models</span> are demonstrated and suggested. Molecular dynamics simulations of potassium ion dynamics inside a gramicidin A channel are used to demonstrate the methodology, although SPA-type <span class="hlt">modeling</span> has also proven useful in analyzing single-molecule experimental time series [J. Phys. Chem. B 113, 118 (2009)]. PMID:19368472</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.A51E..05G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.A51E..05G"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">modeling</span> of smoke transport over the South Asian maritime continent: vertical distributions and topographic effect</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ge, C.; Wang, J.; Yang, Z.; Hyer, E. J.; Reid, J. S.; Chew, B.; Mahamod, M.</p> <p>2011-12-01</p> <p>The online-coupled Weather Research and Forecasting <span class="hlt">model</span> with Chemistry (WRF-Chem) is used in conjunction with the FLAMBE MODIS-based biomass burning emissions to simulate the transport of smoke particles over the southeast Asian Maritime Continent (MC, 10°S - 10°N, 90°E-150°E) during September - October 2006 when the moderate El Nino event caused the largest region biomass burning outbreak since 1998. The <span class="hlt">modeled</span> smoke transport pathway is found to be consistent with the MODIS true color images. Quantitatively, the <span class="hlt">modeled</span> smoke particle mass can explain ~50% of temporal variability in 24-hour average observed PM10 at most ground stations, with linear correlation coefficients often larger than 0.7. Analysis of CALIOP data shows that smoke aerosols are primarily located within 3.5 km above the surface, and we found that smoke injection height in the <span class="hlt">model</span> should be at ~800 m above surface to best match CALIOP observations downwind, instead of 2 km as used in the past literature. Comparison of CALIOP data in October 2006 with that in other years (2007-2010) reveals that the peak of aerosol extinction always occurs at ~1 km above surface, but smoke events in 2006 doubled the aerosol extinction from the surface to 3.5 km. Numerical experiments further show that the Tama Abu topography in Malaysia Peninsula has a significant impact on smoke transport and the surface in the vicinity. A conceptual <span class="hlt">model</span>, based upon our analysis of two-month WRFchem simulation and satellite data, is proposed to explain the meteorological causes for smoke layers above the clouds as seen in the CALIOP data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JESS..125..475R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JESS..125..475R"><span id="translatedtitle">Role of land state in a high resolution <span class="hlt">mesoscale</span> <span class="hlt">model</span> for simulating the Uttarakhand heavy rainfall event over India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rajesh, P. V.; Pattnaik, S.; Rai, D.; Osuri, K. K.; Mohanty, U. C.; Tripathy, S.</p> <p>2016-04-01</p> <p>In 2013, Indian summer monsoon witnessed a very heavy rainfall event (>30 cm/day) over Uttarakhand in north India, claiming more than 5000 lives and property damage worth approximately 40 billion USD. This event was associated with the interaction of two synoptic systems, i.e., intensified subtropical westerly trough over north India and north-westward moving monsoon depression formed over the Bay of Bengal. The event had occurred over highly variable terrain and land surface characteristics. Although global <span class="hlt">models</span> predicted the large scale event, they failed to predict realistic location, timing, amount, intensity and distribution of rainfall over the region. The goal of this study is to assess the impact of land state conditions in simulating this severe event using a high resolution <span class="hlt">mesoscale</span> <span class="hlt">model</span>. The land conditions such as multi-layer soil moisture and soil temperature fields were generated from High Resolution Land Data Assimilation (HRLDAS) <span class="hlt">modelling</span> system. Two experiments were conducted namely, (1) CNTL (Control, without land data assimilation) and (2) LDAS, with land data assimilation (i.e., with HRLDAS-based soil moisture and temperature fields) using Weather Research and Forecasting (WRF) <span class="hlt">modelling</span> system. Initial soil moisture correlation and root mean square error for LDAS is 0.73 and 0.05, whereas for CNTL it is 0.63 and 0.053 respectively, with a stronger heat low in LDAS. The differences in wind and moisture transport in LDAS favoured increased moisture transport from Arabian Sea through a convectively unstable region embedded within two low pressure centers over Arabian Sea and Bay of Bengal. The improvement in rainfall is significantly correlated to the persistent generation of potential vorticity (PV) in LDAS. Further, PV tendency analysis confirmed that the increased generation of PV is due to the enhanced horizontal PV advection component rather than the diabatic heating terms due to modified flow fields. These results suggest that, two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6227005','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6227005"><span id="translatedtitle">An evaluation of sea level cyclone forecasts produced by NMC's <span class="hlt">Nested</span>-Grid <span class="hlt">Model</span> and Global Spectral <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Smith, B.B.; Mullen, S.L. Arizona Univ., Tucson )</p> <p>1993-03-01</p> <p>An analysis of the 24- and 48-h sea level cyclone errors occurring in the NMC's <span class="hlt">Nested</span>-Grid <span class="hlt">Model</span> (NGM) and the Aviation Run of the Global Spectral <span class="hlt">Model</span> (AVN) during the 1987/1988 and 1989/1990 winter seasons is presented. Central pressure, 1000-500-mb thickness, and displacement errors for cyclone center are compared, and the circumstances under which one <span class="hlt">model</span> performs better than the other are documented. Overall, the NGM slightly overdeepens cyclones and the T80 AVN underdeepens cyclones when both <span class="hlt">models</span> are verified against the NGM initial panel. Both <span class="hlt">models</span> underdevelop oceanic and deep cyclones. The pressure error variance tends to be smaller for the AVN, particularly at 48 h. It is inferred that the variability of individual central pressure forecasts is smaller for the AVN. Mean absolute displacement errors are smaller for the T80 AVN than the NGM. 35 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6914666','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6914666"><span id="translatedtitle">Use of cloud observations and <span class="hlt">mesoscale</span> meteorology <span class="hlt">models</span> to evaluate and improve cloud parameterizations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Walcek, C.J.</p> <p>1992-10-30</p> <p>This research program utilizes satellite and surface-derived cloud observations together with standard meteorological measurements to evaluate and improve our ability to accurately diagnose cloud coverage. Results are to be used to compliment existing or future parameterizations of cloud effects in general circulation <span class="hlt">models</span>, since nearly all cloud parameterizations must specify a fractional area of cloud coverage when calculating radiative or dynamic cloud effects, and current parameterizations rely on rather crude cloud cover estimates. We have compiled and reviewed a list of formulations used by various climate research groups to specify cloud cover. We find considerable variability between formulations used by various climate and meteorology <span class="hlt">models</span>, and under some conditions, one formulation will produce a zero cloud amount, while an alternate formulation calculates 95% cloud cover under the same environmental conditions. All formulations hypothesize that cloud cover is predominantly determined by the average relative humidity, although some formulations allow local temperature lapse rates and vertical velocities to influence cloud amount.</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/2012AGUFM.H33F1393K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.H33F1393K"><span id="translatedtitle">Multiscale analysis of surface soil moisture dynamics in a <span class="hlt">mesoscale</span> catchment utilizing an integrated ecohydrological <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>Korres, W.; Reichenau, T. G.; Schneider, K.</p> <p>2012-12-01</p> <p>Soil moisture is one of the fundamental variables in hydrology, meteorology and agriculture, influencing the partitioning of solar energy into latent and sensible heat flux as well as the partitioning of precipitation into runoff and percolation. Numerous studies have shown that in addition to natural factors (rainfall, soil, topography etc.) agricultural management is one of the key drivers for spatio-temporal patterns of soil moisture in agricultural landscapes. Interactions between plant growth, soil hydrology and soil nitrogen transformation processes are <span class="hlt">modeled</span> by using a dynamically coupled <span class="hlt">modeling</span> approach. The process-based ecohydrological <span class="hlt">model</span> components of the integrated decision support system DANUBIA are used to identify the important processes and feedbacks determining soil moisture patterns in agroecosystems. Integrative validation of plant growth and surface soil moisture dynamics serves as a basis for a spatially distributed <span class="hlt">modeling</span> analysis of surface soil moisture patterns in the northern part of the Rur catchment (1100 sq km), Western Germany. An extensive three year dataset (2007-2009) of surface soil moisture-, plant- (LAI, organ specific biomass and N) and soil- (texture, N, C) measurements was collected. Plant measurements were carried out biweekly for winter wheat, maize, and sugar beet during the growing season. Soil moisture was measured with three FDR soil moisture stations. Meteorological data was measured with an eddy flux station. The results of the <span class="hlt">model</span> validation showed a very good agreement between the <span class="hlt">modeled</span> plant parameters (biomass, green LAI) and the measured parameters with values between 0.84 and 0.98 (Willmotts index of agreement). The <span class="hlt">modeled</span> surface soil moisture (0 - 20 cm) showed also a very favorable agreement with the measurements for winter wheat and sugar beet with an RMSE between 1.68 and 3.45 Vol.-%. For maize, the RMSE was less favorable particularly in the 1.5 months prior to harvest. The <span class="hlt">modeled</span> soil</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA631433','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA631433"><span id="translatedtitle">A Rapidly Relocatable, Coupled <span class="hlt">Mesoscale</span> <span class="hlt">Modeling</span> System for Naval Special Warfare</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2016-06-13</p> <p><span class="hlt">model</span>. This capability offers a predictive capability of environmental parameters at scales on the order of 1 km, which is crucial for NSW...allow for operational support while at the same time providing a technology which can be scaled to larger systems and transitioned to Production...applications (e.g., HYCOM-CICE, COAMPS-NCOM) to address air-sea interactions. Small Scale Oceanography [PI: Rowley – 6.4]: the development and transition</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008APS..DFD.GL005C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008APS..DFD.GL005C"><span id="translatedtitle"><span class="hlt">Mesoscale</span> <span class="hlt">Model</span> for Blood Cell Adhesion and Transport using Ellipsoidal Particles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chesnutt, Jennifer; Marshall, Jeffrey</p> <p>2008-11-01</p> <p>A novel discrete-element computational <span class="hlt">model</span> for efficient transport, collision, and adhesion of ellipsoidal particles is applied to blood cells adhering through receptor-ligand binding in three-dimensional flow. The <span class="hlt">model</span> has been used for simulation of over 13,000 adhesive cells through approximation of blood cells as elastic particles and other physically-justifiable approximations. The computational <span class="hlt">model</span> is validated against experimental data of red blood cell (RBC) aggregation in shear and channel flows. The structure of aggregates formed by RBCs is analyzed by various measures that relate RBCs which are in contact with each other and that characterize an aggregate by fitting an ellipse to the projection of cells contained in the aggregate. Factors such as shear rate and adhesive surface energy density between cells are examined for their effects on the size and structure of RBC aggregates in both two- and three-dimensional computations. The effect of RBC aggregation on migration of blood elements (RBCs, leukocytes, platelets) in channel flow is also investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1817875F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1817875F"><span id="translatedtitle">Domain <span class="hlt">nesting</span> for multi-scale large eddy simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fuka, Vladimir; Xie, Zheng-Tong</p> <p>2016-04-01</p> <p>The need to simulate city scale areas (O(10 km)) with high resolution within street canyons in certain areas of interests necessitates different grid resolutions in different part of the simulated area. General purpose computational fluid dynamics codes typically employ unstructured refined grids while <span class="hlt">mesoscale</span> meteorological <span class="hlt">models</span> more often employ <span class="hlt">nesting</span> of computational domains. ELMM is a large eddy simulation <span class="hlt">model</span> for the atmospheric boundary layer. It employs orthogonal uniform grids and for this reason domain <span class="hlt">nesting</span> was chosen as the approach for simulations in multiple scales. Domains are implemented as sets of MPI processes which communicate with each other as in a normal non-<span class="hlt">nested</span> run, but also with processes from another (outer/inner) domain. It should stressed that the duration of solution of time-steps in the outer and in the inner domain must be synchronized, so that the processes do not have to wait for the completion of their boundary conditions. This can achieved by assigning an appropriate number of CPUs to each domain, and to gain high efficiency. When <span class="hlt">nesting</span> is applied for large eddy simulation, the inner domain receives inflow boundary conditions which lack turbulent motions not represented by the outer grid. ELMM remedies this by optional adding of turbulent fluctuations to the inflow using the efficient method of Xie and Castro (2008). The spatial scale of these fluctuations is in the subgrid-scale of the outer grid and their intensity will be estimated from the subgrid turbulent kinetic energy in the outer grid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930052041&hterms=sponge&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsponge','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930052041&hterms=sponge&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsponge"><span id="translatedtitle">A nonreflecting upper boundary condition for anelastic nonhydrostatic <span class="hlt">mesoscale</span> gravity-wave <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>Kim, Young-Joon; Kar, Sajal K.; Arakawa, Akio</p> <p>1993-01-01</p> <p>A sponge layer is formulated to prevent spurious reflection of vertically propagating quasi-stationary gravity waves at the upper boundary of a two-dimensional numerical anelastic nonhydrostatic <span class="hlt">model</span>. The sponge layer includes damping of both Newtonian-cooling type and Rayleigh-friction type, whose coefficients are determined in such a way that the reflectivity of wave energy at the bottom of the layer is zero. Unlike the formulations in earlier studies, our formulation includes the effects of vertical discretization, vertical mean density variation, and nonhydrostaticity. This sponge formulation is found effective in suppressing false downward reflection of waves for various types of quasi-stationary forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GMD.....8.1919F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GMD.....8.1919F"><span id="translatedtitle">AROME-WMED, a real-time <span class="hlt">mesoscale</span> <span class="hlt">model</span> designed for the HyMeX special observation periods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fourrié, N.; Bresson, É.; Nuret, M.; Jany, C.; Brousseau, P.; Doerenbecher, A.; Kreitz, M.; Nuissier, O.; Sevault, E.; Bénichou, H.; Amodei, M.; Pouponneau, F.</p> <p>2015-07-01</p> <p>During autumn 2012 and winter 2013, two special observation periods (SOPs) of the HYdrological cycle in the Mediterranean EXperiment (HyMeX) took place. For the preparatory studies and to support the instrument deployment during the field campaign, a dedicated version of the operational convective-scale Application of Research to Operations at <span class="hlt">Mesoscale</span> (AROME)-France <span class="hlt">model</span> was developed: the AROME-WMED (West Mediterranean Sea) <span class="hlt">model</span>. It covers the western Mediterranean basin with a 48 h forecast range. It provided real-time analyses and forecasts which were sent daily to the HyMeX operational centre to forecast high-precipitation events and to help decision makers on the deployment of meteorological instruments. This paper presents the main features of this numerical weather prediction system in terms of data assimilation and forecast. Some specific data of the HyMeX SOP were assimilated in real time. The forecast skill of AROME-WMED is then assessed with objective scores and compared to the operational AROME-France <span class="hlt">model</span>, for both autumn 2012 (05 September to 06 November 2012) and winter 2013 (01 February to 15 March 2013) SOPs. The overall performance of AROME-WMED is good for the first HyMeX special observation period (SOP1) (i.e. mean 2 m temperature root mean square error (RMSE) of 1.7 °C and mean 2 m relative humidity RMSE of 10 % for the 0-30 h forecast ranges) and similar to those of AROME-France for the 0-30 h common forecast range (maximal absolute difference of 2 m temperature RMSE of 0.2 °C and 0.21 % for the 2 m relative humidity); conversely, for the 24-48 h forecast range it is less accurate (relative loss between 10 and 12 % in 2 m temperature and relative humidity RMSE, and equitable threat score (ETS) for 24 h accumulated rainfall), but it remains useful for scheduling observation deployment. The characteristics of parameters, such as precipitation, temperature or humidity, are illustrated by one heavy precipitation case study that occurred</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.......143B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.......143B"><span id="translatedtitle">Quantifying wind resource assessment and grid integration challenges for Delaware offshore wind power utilizing <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> techniques</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brodie, Joseph F.</p> <p></p> <p>Offshore wind in the United States continues to be a focused area of research as our society grapples with the Earth's changing climate and our ongoing and increasing demand for electricity. While the first offshore wind project in the U.S. is expected to be operational soon, much still remains to be done to help improve viability of offshore wind in additional locations. This dissertation discusses three studies conducted to improve the understanding of and expectations from developing wind energy in the Delaware Wind Energy Area off the Delaware coast. The first study examines the capabilities of the Weather Research and Forecasting (WRF) <span class="hlt">model</span> to account for variations in wind farm array geometries in an idealized set-up of the <span class="hlt">model</span>, and determines features of those array geometries that can positively influence the energy production of an offshore farm. The second study investigates the impacts that the misprediction of wind ramp events would have on the interaction of an offshore wind farm with the electricity grid, quantifying some of these impacts and discussing factors which contribute to grid instability. The third study combines the knowledge gained in the first two studies to evaluate potential wind farm array geometries in a regional study of the Delaware Wind Energy Area using WRF along with a selection of case study dates selected to examine the impacts of the synoptic variability of the region throughout the year. These studies demonstrate that careful consideration of the meteorology and climatology of a region when determining the layout of an offshore wind array can improve the power production of the farm, thereby improving wind farm viability. It is shown that using a <span class="hlt">mesoscale</span> <span class="hlt">model</span> that incorporates a wind farm parameterization can improve resource assessment by allowing the assessment to evaluate the wind farm's interactions with the weather and climate in the Delaware Wind Energy Area. Furthermore, it is shown that while certain synoptic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24094332','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24094332"><span id="translatedtitle">Is HIV short-sighted? Insights from a multistrain <span class="hlt">nested</span> <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>Lythgoe, Katrina A; Pellis, Lorenzo; Fraser, Christophe</p> <p>2013-10-01</p> <p>An important component of pathogen evolution at the population level is evolution within hosts. Unless evolution within hosts is very slow compared to the duration of infection, the composition of pathogen genotypes within a host is likely to change during the course of an infection, thus altering the composition of genotypes available for transmission as infection progresses. We develop a <span class="hlt">nested</span> <span class="hlt">modeling</span> approach that allows us to follow the evolution of pathogens at the epidemiological level by explicitly considering within-host evolutionary dynamics of multiple competing strains and the timing of transmission. We use the framework to investigate the impact of short-sighted within-host evolution on the evolution of virulence of human immunodeficiency virus (HIV), and find that the topology of the within-host adaptive landscape determines how virulence evolves at the epidemiological level. If viral reproduction rates increase significantly during the course of infection, the viral population will evolve a high level of virulence even though this will reduce the transmission potential of the virus. However, if reproduction rates increase more modestly, as data suggest, our <span class="hlt">model</span> predicts that HIV virulence will be only marginally higher than the level that maximizes the transmission potential of the virus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24691415','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24691415"><span id="translatedtitle">Lipid-based nanodiscs as <span class="hlt">models</span> for studying <span class="hlt">mesoscale</span> coalescence--a transport limited case.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hu, Andrew; Fan, Tai-Hsi; Katsaras, John; Xia, Yan; Li, Ming; Nieh, Mu-Ping</p> <p>2014-07-28</p> <p>Lipid-based nanodiscs (bicelles) are able to form in mixtures of long- and short-chain lipids. Initially, they are of uniform size but grow upon dilution. Previously, nanodisc growth kinetics have been studied using time-resolved small angle neutron scattering (SANS), a technique which is not well suited for probing their change in size immediately after dilution. To address this, we have used dynamic light scattering (DLS), a technique which permits the collection of useful data in a short span of time after dilution of the system. The DLS data indicate that the negatively charged lipids in nanodiscs play a significant role in disc stability and growth. Specifically, the charged lipids are most likely drawn out from the nanodiscs into solution, thereby reducing interparticle repulsion and enabling the discs to grow. We describe a population balance <span class="hlt">model</span>, which takes into account Coulombic interactions and adequately predicts the initial growth of nanodiscs with a single parameter - i.e., surface potential. The results presented here strongly support the notion that the disc coalescence rate strongly depends on nanoparticle charge density. The present system containing low-polydispersity lipid nanodiscs serves as a good <span class="hlt">model</span> for understanding how charged discoidal micelles coalesce.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1157123','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1157123"><span id="translatedtitle">Lipid-Based Nanodiscs as <span class="hlt">Models</span> for Studying <span class="hlt">Mesoscale</span> Coalescence A Transport Limited Case</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hu, Andrew; Fan, Tai-Hsi; Katsaras, John; Xia, Yan; Li, Ming; Nieh, Mu-Ping</p> <p>2014-01-01</p> <p>Lipid-based nanodiscs (bicelles) are able to form in mixtures of long- and short-chain lipids. Initially, they are of uniform size but grow upon dilution. Previously, nanodisc growth kinetics have been studied using time-resolved small angle neutron scattering (SANS), a technique which is not well suited for probing their change in size immediately after dilution. To address this, we have used dynamic light scattering (DLS), a technique which permits the collection of useful data in a short span of time after dilution of the system. The DLS data indicate that the negatively charged lipids in nanodiscs play a significant role in disc stability and growth. Specifically, the charged lipids are most likely drawn out from the nanodiscs into solution, thereby reducing interparticle repulsion and enabling the discs to grow. We describe a population balance <span class="hlt">model</span>, which takes into account Coulombic interactions and adequately predicts the initial growth of nanodiscs with a single parameter i.e., surface potential. The results presented here strongly support the notion that the disc coalescence rate strongly depends on nanoparticle charge density. The present system containing low-polydispersity lipid nanodiscs serves as a good <span class="hlt">model</span> for understanding how charged discoidal micelles coalesce.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19960034359','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19960034359"><span id="translatedtitle">Forecast skill of a high-resolution real-time <span class="hlt">mesoscale</span> <span class="hlt">model</span> designed for weather support of operations at Kennedy Space Center and Cape Canaveral Air Station</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Taylor, Gregory E.; Zack, John W.; Manobianco, John</p> <p>1994-01-01</p> <p>NASA funded <span class="hlt">Mesoscale</span> Environmental Simulations and Operations (MESO), Inc. to develop a version of the <span class="hlt">Mesoscale</span> Atmospheric Simulation System (MASS). The <span class="hlt">model</span> has been modified specifically for short-range forecasting in the vicinity of KSC/CCAS. To accomplish this, the <span class="hlt">model</span> domain has been limited to increase the number of horizontal grid points (and therefore grid resolution) and the <span class="hlt">model</span>' s treatment of precipitation, radiation, and surface hydrology physics has been enhanced to predict convection forced by local variations in surface heat, moisture fluxes, and cloud shading. The objective of this paper is to (1) provide an overview of MASS including the real-time initialization and configuration for running the data pre-processor and <span class="hlt">model</span>, and (2) to summarize the preliminary evaluation of the <span class="hlt">model</span>'s forecasts of temperature, moisture, and wind at selected rawinsonde station locations during February 1994 and July 1994. MASS is a hydrostatic, three-dimensional <span class="hlt">modeling</span> system which includes schemes to represent planetary boundary layer processes, surface energy and moisture budgets, free atmospheric long and short wave radiation, cloud microphysics, and sub-grid scale moist convection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A11J0199B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A11J0199B"><span id="translatedtitle">Constraining Methane Emissions from Natural Gas Production in Northeastern Pennsylvania Using Aircraft Observations and <span class="hlt">Mesoscale</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>Barkley, Z.; Davis, K.; Lauvaux, T.; Miles, N.; Richardson, S.; Martins, D. K.; Deng, A.; Cao, Y.; Sweeney, C.; Karion, A.; Smith, M. L.; Kort, E. A.; Schwietzke, S.</p> <p>2015-12-01</p> <p>Leaks in natural gas infrastructure release methane (CH4), a potent greenhouse gas, into the atmosphere. The estimated fugitive emission rate associated with the production phase varies greatly between studies, hindering our understanding of the natural gas energy efficiency. This study presents a new application of inverse methodology for estimating regional fugitive emission rates from natural gas production. Methane observations across the Marcellus region in northeastern Pennsylvania were obtained during a three week flight campaign in May 2015 performed by a team from the National Oceanic and Atmospheric Administration (NOAA) Global Monitoring Division and the University of Michigan. In addition to these data, CH4 observations were obtained from automobile campaigns during various periods from 2013-2015. An inventory of CH4 emissions was then created for various sources in Pennsylvania, including coalmines, enteric fermentation, industry, waste management, and unconventional and conventional wells. As a first-guess emission rate for natural gas activity, a leakage rate equal to 2% of the natural gas production was emitted at the locations of unconventional wells across PA. These emission rates were coupled to the Weather Research and Forecasting <span class="hlt">model</span> with the chemistry module (WRF-Chem) and atmospheric CH4 concentration fields at 1km resolution were generated. Projected atmospheric enhancements from WRF-Chem were compared to observations, and the emission rate from unconventional wells was adjusted to minimize errors between observations and simulation. We show that the <span class="hlt">modeled</span> CH4 plume structures match observed plumes downwind of unconventional wells, providing confidence in the methodology. In all cases, the fugitive emission rate was found to be lower than our first guess. In this initial emission configuration, each well has been assigned the same fugitive emission rate, which can potentially impair our ability to match the observed spatial variability</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6889186','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6889186"><span id="translatedtitle">Application of an advanced atmospheric <span class="hlt">mesoscale</span> <span class="hlt">model</span> to dispersion in the Rocky Flats, Colorado vicinity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Poulos, G.S.; Bossert, J.E.</p> <p>1993-01-01</p> <p>Atmospheric Studies in Complex Terrain (ASCOT) program sponsored a field experiment in the winter of 1991 near Rocky Flats, Colorado. Both meteorological and tracer dispersion measurements were taken. These two data sets provided an opportunity to investigate the influence of terrain-generated, radiatively-driven flows on the dispersion of the tracer. We use the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS), originally developed at Colorado State University, to simulate meteorological conditions and tracer dispersion on the case night of 4-5 February 1991. The simulations described herein reveal considerable information about the extent to which the Rocky Mountains influence the flow along the Front Range , the importance of diffusion when simulating drainage flows and the computing needs of simulations in complex terrain regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10128282','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10128282"><span id="translatedtitle">Application of an advanced atmospheric <span class="hlt">mesoscale</span> <span class="hlt">model</span> to dispersion in the Rocky Flats, Colorado vicinity</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Poulos, G.S.; Bossert, J.E.</p> <p>1993-02-01</p> <p>Atmospheric Studies in Complex Terrain (ASCOT) program sponsored a field experiment in the winter of 1991 near Rocky Flats, Colorado. Both meteorological and tracer dispersion measurements were taken. These two data sets provided an opportunity to investigate the influence of terrain-generated, radiatively-driven flows on the dispersion of the tracer. We use the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS), originally developed at Colorado State University, to simulate meteorological conditions and tracer dispersion on the case night of 4-5 February 1991. The simulations described herein reveal considerable information about the extent to which the Rocky Mountains influence the flow along the Front Range , the importance of diffusion when simulating drainage flows and the computing needs of simulations in complex terrain regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1349010','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1349010"><span id="translatedtitle"><span class="hlt">Meso-scale</span> framework for <span class="hlt">modeling</span> granular material using computed tomography</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Turner, Anne K.; Kim, Felix H.; Penumadu, Dayakar; Herbold, Eric B.</p> <p>2016-03-17</p> <p>Numerical <span class="hlt">modeling</span> of unconsolidated granular materials is comprised of multiple nonlinear phenomena. Accurately capturing these phenomena, including grain deformation and intergranular forces depends on resolving contact regions several orders of magnitude smaller than the grain size. Here, we investigate a method for capturing the morphology of the individual particles using computed X-ray and neutron tomography, which allows for accurate characterization of the interaction between grains. The ability of these numerical approaches to determine stress concentrations at grain contacts is important in order to capture catastrophic splitting of individual grains, which has been shown to play a key role in the plastic behavior of the granular material on the continuum level. Discretization approaches, including mesh refinement and finite element type selection are presented to capture high stress concentrations at contact points between grains. The effect of a grain’s coordination number on the stress concentrations is also investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1349010-meso-scale-framework-modeling-granular-material-using-computed-tomography','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1349010-meso-scale-framework-modeling-granular-material-using-computed-tomography"><span id="translatedtitle"><span class="hlt">Meso-scale</span> framework for <span class="hlt">modeling</span> granular material using computed tomography</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Turner, Anne K.; Kim, Felix H.; Penumadu, Dayakar; ...</p> <p>2016-03-17</p> <p>Numerical <span class="hlt">modeling</span> of unconsolidated granular materials is comprised of multiple nonlinear phenomena. Accurately capturing these phenomena, including grain deformation and intergranular forces depends on resolving contact regions several orders of magnitude smaller than the grain size. Here, we investigate a method for capturing the morphology of the individual particles using computed X-ray and neutron tomography, which allows for accurate characterization of the interaction between grains. The ability of these numerical approaches to determine stress concentrations at grain contacts is important in order to capture catastrophic splitting of individual grains, which has been shown to play a key role in themore » plastic behavior of the granular material on the continuum level. Discretization approaches, including mesh refinement and finite element type selection are presented to capture high stress concentrations at contact points between grains. The effect of a grain’s coordination number on the stress concentrations is also investigated.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910037950&hterms=skillman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dskillman','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910037950&hterms=skillman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dskillman"><span id="translatedtitle">Jet streak circulations associated with a moderate snowfall event as diagnosed from NGM <span class="hlt">model</span> output. [<span class="hlt">Nested</span> Grid <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>Kocin, Paul J.; Uccellini, Louis W.; Skillman, William C.; Grumm, Richard H.</p> <p>1989-01-01</p> <p>The existence, evolution, and interaction of vertical circulations associated with upper-level jet streaks during a moderate snowfall event are diagnosed using a <span class="hlt">nested</span> grid <span class="hlt">model</span> (NGM). The event itself is overviewed, and the diagnosis of transverse circulations utilizing NGM output is discussed. Focus is placed on the identification of the horizontal and vertical components of the circulation, the temporal evolution of the circulation, and the comparison of the circulation from successive <span class="hlt">model</span> forecasts. A preliminary analysis of the <span class="hlt">model</span> data indicates that the horizontal and vertical branches of the circulations can be diagnosed from the <span class="hlt">model</span> output, and the horizontal and vertical components of the circulations may be identified and followed during an individual forecast cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7767Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7767Y"><span id="translatedtitle">Hydrological <span class="hlt">model</span> parameters identification in a coastal <span class="hlt">nested</span> catchment in Mersin province (SE Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yıldırım, Ümit; Jomaa, Seifeddine; Güler, Cüneyt; Rode, Michael</p> <p>2016-04-01</p> <p>It is known that the coastal Mediterranean region is facing a serious problem of water resources exploitation due to the rapid demographic, socio-economic, land use and climate changes. The hydrological <span class="hlt">modeling</span> has proven to be an efficient tool for better water resources prediction and management. In this study, the HYdrological Predictions for the Environment (HYPE) <span class="hlt">model</span> was setup on the <span class="hlt">nested</span> coastal Sorgun catchment in Turkey (449 km2). This catchment is located in the east part of the Mersin province and is characterized by extremely varied topography, land use, and population density in semi-arid Mediterranean climate conditions. First, the <span class="hlt">model</span> was calibrated at the catchment outlet (Sarilar) for the period 2003-2006. Second, the <span class="hlt">model</span> was validated temporally for the period 2009-2013 at daily and monthly time intervals. In addition, the <span class="hlt">model</span> performance was tested spatially using an internal station (B. Sorgun, 269 km2) located in the headwater region. Results showed that the HYPE <span class="hlt">model</span> could reproduce the measured daily discharge significantly well (Nash Sutcliffe Efficiency (NSE) were 0.78 and 0.68 for calibration and validation periods, respectively). For monthly time step, the <span class="hlt">model</span> performs better compared with daily time interval (NSE were 0.92 and 0.83 for calibration and validation periods, respectively). The <span class="hlt">model</span> could represent the water balance relatively good at daily and monthly time steps, where the lowest PBIAS (percentage bias) were - 4.19% and - 3.53% for daily and monthly time intervals, respectively (considering the whole period). Results revealed, however, the agreement between the predicted and measured discharge was reduced, when the same best optimized <span class="hlt">model</span>-parameters at Sarilar gauging station (catchment outlet) were used at B. Sorgun station (internal station). This <span class="hlt">model</span> transferability less performance at internal station can be explained by the clear changes in terms of land use, soil type and precipitation rate in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JChPh.145n4109D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JChPh.145n4109D"><span id="translatedtitle">cDPD: A new dissipative particle dynamics method for <span class="hlt">modeling</span> electrokinetic phenomena at the <span class="hlt">mesoscale</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deng, Mingge; Li, Zhen; Borodin, Oleg; Karniadakis, George Em</p> <p>2016-10-01</p> <p>We develop a "charged" dissipative particle dynamics (cDPD) <span class="hlt">model</span> for simulating mesoscopic electrokinetic phenomena governed by the stochastic Poisson-Nernst-Planck and the Navier-Stokes equations. Specifically, the transport equations of ionic species are incorporated into the DPD framework by introducing extra degrees of freedom and corresponding evolution equations associated with each DPD particle. Diffusion of ionic species driven by the ionic concentration gradient, electrostatic potential gradient, and thermal fluctuations is captured accurately via pairwise fluxes between DPD particles. The electrostatic potential is obtained by solving the Poisson equation on the moving DPD particles iteratively at each time step. For charged surfaces in bounded systems, an effective boundary treatment methodology is developed for imposing both the correct hydrodynamic and electrokinetics boundary conditions in cDPD simulations. To validate the proposed cDPD <span class="hlt">model</span> and the corresponding boundary conditions, we first study the electrostatic structure in the vicinity of a charged solid surface, i.e., we perform cDPD simulations of the electrostatic double layer and show that our results are in good agreement with the well-known mean-field theoretical solutions. We also simulate the electrostatic structure and capacity densities between charged parallel plates in salt solutions with different salt concentrations. Moreover, we employ the proposed methodology to study the electro-osmotic and electro-osmotic/pressure-driven flows in a micro-channel. In the latter case, we simulate the dilute poly-electrolyte solution drifting by electro-osmotic flow in a micro-channel, hence demonstrating the flexibility and capability of this method in studying complex fluids with electrostatic interactions at the micro- and nano-scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/861016','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/861016"><span id="translatedtitle">Impact of Agricultural Practice on Regional Climate in a CoupledLand Surface <span class="hlt">Mesoscale</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.</p> <p>2004-07-01</p> <p>The land surface has been shown to form strong feedbacks with climate due to linkages between atmospheric conditions and terrestrial ecosystem exchanges of energy, momentum, water, and trace gases. Although often ignored in <span class="hlt">modeling</span> studies, land management itself may form significant feedbacks. Because crops are harvested earlier under drier conditions, regional air temperature, precipitation, and soil moisture, for example, affect harvest timing, particularly of rain-fed crops. This removal of vegetation alters the land surface characteristics and may, in turn, affect regional climate. We applied a coupled climate(MM5) and land-surface (LSM1) <span class="hlt">model</span> to examine the effects of early and late winter wheat harvest on regional climate in the Department of Energy Atmospheric Radiation Measurement (ARM) Climate Research Facility in the Southern Great Plains, where winter wheat accounts for 20 percent of the land area. Within the winter wheat region, simulated 2 m air temperature was 1.3 C warmer in the Early Harvest scenario at mid-day averaged over the two weeks following harvest. Soils in the harvested area were drier and warmer in the top 10 cm and wetter in the 10-20 cm layer. Midday soils were 2.5 C warmer in the harvested area at mid-day averaged over the two weeks following harvest. Harvest also dramatically altered latent and sensible heat fluxes. Although differences between scenarios diminished once both scenarios were harvested, the short-term impacts of land management on climate were comparable to those from land cover change demonstrated in other studies.</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://www.osti.gov/scitech/biblio/1020397','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1020397"><span id="translatedtitle">Performance of <span class="hlt">mesoscale</span> <span class="hlt">modeling</span> methods for predicting microstructure, mobility and rheology of charged suspensions.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pierce, Flint; Grillet, Anne Mary; Grest, Gary Stephen; Lechman, Jeremy B.; Plimpton, Steven James; in't Veld, Pieter J.; Schunk, Peter Randall; Heine, D. R.; Stoltz, C.; Weiss, Horst; Jendrejack, R.; Petersen, Matthew K.</p> <p>2010-06-01</p> <p>In this presentation we examine the accuracy and performance of a suite of discrete-element-<span class="hlt">modeling</span> approaches to predicting equilibrium and dynamic rheological properties of polystyrene suspensions. What distinguishes each approach presented is the methodology of handling the solvent hydrodynamics. Specifically, we compare stochastic rotation dynamics (SRD), fast lubrication dynamics (FLD) and dissipative particle dynamics (DPD). Method-to-method comparisons are made as well as comparisons with experimental data. Quantities examined are equilibrium structure properties (e.g. pair-distribution function), equilibrium dynamic properties (e.g. short- and long-time diffusivities), and dynamic response (e.g. steady shear viscosity). In all approaches we deploy the DLVO potential for colloid-colloid interactions. Comparisons are made over a range of volume fractions and salt concentrations. Our results reveal the utility of such methods for long-time diffusivity prediction can be dubious in certain ranges of volume fraction, and other discoveries regarding the best formulation to use in predicting rheological response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870008842&hterms=static+dynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dstatic%2Bdynamic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870008842&hterms=static+dynamic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dstatic%2Bdynamic"><span id="translatedtitle">Dynamic and static initialization of a <span class="hlt">mesoscale</span> <span class="hlt">model</span> using VAS satellite data. M.S. Thesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Beauchamp, James G.</p> <p>1985-01-01</p> <p>Various combinations of temperature and moisture data from the VISSR Atmospheric Sounder (VAS), conventional radiosonde data, and National Meteorological Center (NMC) global analysis, were used in a successive-correction type of objective-analysis procedure to produce analyses for 1200 GMT. The NMC global analyses served as the first-guess field for all of the objective analysis procedures. The first-guess field was enhanced by radiosonde data alone, VAS data alone, both radiosonde and VAS data, or by neither data source. In addition, two objective analyses were used in a dynamic initialization: one included only radiosonde data and the other used both radiosonde and VAS data. The dependence of 12 hour forecast skill on data type and the methods by which the data were used in the analysis/initialization were then investigated. This was done by comparison of forecast and observed fields, of sea-level pressure, temperature, wind, moisture, and accumulated precipitation. The use of VAS data in the initial conditions had a slight positive impact upon forecast temperature and moisture but a negative impact upon forecast wind. This was true for both the static and dynamic initialization experiments. Precipitation forecasts from all of the <span class="hlt">model</span> simulations were nearly the same.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810294R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810294R"><span id="translatedtitle">Impact of observations in a <span class="hlt">mesoscale</span> NWP <span class="hlt">model</span> in the Arctic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Randriamampianina, Roger; Máté, Mile; Guedj, Stephanie; Schyberg, Harald</p> <p>2016-04-01</p> <p>In the frame of the EU-funded project ACCESS (Arctic Climate Change, Economy and Society), MET Norway aimed 1) to describe the present monitoring and forecasting capabilities in the Arctic; and 2) to identify the key factors limiting the forecasting capabilities and to give recommendations on key areas to improve the forecasting capabilities in the Arctic. The first task was assessed using observing system experiments (OSE), while second one was evaluated applying observing system simulation experiments (OSSE). We have observed that the NWP forecast quality is lower in the Arctic than in the regions further south. An earlier research indicated that one of factors behind this is the composition of the observing system in the Arctic, in particular the scarceness of conventional observations. To further assess possible strategies for alleviating the situation and propose scenarios for a future Arctic observing system, we have performed a set of experiments to gain a more detailed insight in the contribution of the components of the present observing system in a regional state-of-the-art non-hydrostatic NWP <span class="hlt">model</span>. These observing system experiments have been evaluated 1) in terms of a measure of the information content of observations with respect to analysis quality and 2) with respect to the impact on forecasts assessed (a) through case studies, (b) through a norm measuring the impact on forecasts and (c) through the quality of forecasts verified with available reference observations. The OSE studies show that conventional observations (Synop, Buoys) can play an important role in correcting the surface state of the <span class="hlt">model</span>, but prove that the present upper-air conventional (Radiosondes, Arcraft) observations in the area are too scarce to have a significant effect on forecasts. We demonstrate that satellite sounding data play important role in improving forecasts quality at present. This is the case with the satellite temperature sounding data (AMSU-A, IASI), as well as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMEP33B0851L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMEP33B0851L"><span id="translatedtitle"><span class="hlt">Nested</span> <span class="hlt">modeling</span> approach to quantify sediment transport pathways and temporal variability of barrier island evolution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Long, J. W.; Dalyander, S.; Sherwood, C. R.; Thompson, D. M.; Plant, N. G.</p> <p>2012-12-01</p> <p>The Chandeleur Islands, situated off the coast of Louisiana in the Gulf of Mexico, comprise a sand-starved barrier island system that has been disintegrating over the last decade. The persistent sediment transport in this area is predominantly directed alongshore but overwash and inundation during storm conditions has fragmented the island and reduced the subaerial extent by almost 75% since 2001. From 2010-2011 a sand berm was constructed along the Gulf side of the island adding 20 million cubic yards of sediment to this barrier island system. The redistribution of this sediment, particularly whether it remains in the active system and progrades the barrier island, has been evaluated using a series of numerical <span class="hlt">models</span> and an extensive set of in situ and remote sensing observations. We have developed a coupled numerical <span class="hlt">modeling</span> system capable of simulating morphologic evolution of the sand berm and barrier island using observations and predictions of regional and nearshore oceanographic processes. A <span class="hlt">nested</span> approach provides large scale oceanographic information to force island evolution in a series of smaller grids, including two nearshore domains that are designed to simulate (1) the persistent alongshore sediment transport O(months-years) and (2) the overwash and breaching of the island/berm due to cross-shore forcing driven by winter cold fronts and tropical storms (O(hours-days)). The coupled <span class="hlt">model</span> is evaluated using the observations of waves, water levels, currents, and topographic/morphologic change. <span class="hlt">Modeled</span> processes are then used to identify the dominant sediment transport pathways and quantify the role of alongshore and cross-shore sediment transport in evolving the barrier island over a range of temporal scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940017858','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940017858"><span id="translatedtitle"><span class="hlt">Mesoscale</span> simulations of the November 25-26 and December 5-6 cirrus cases using the RAMS <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>Harrington, J. L.; Meyers, Michael P.; Cotton, William R.</p> <p>1993-01-01</p> <p>The Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS), developed at Colorado State University, was used during the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE) 2 (13 Nov. through 6 Dec. 1991) to provide real time forecasts of cirrus clouds. Forecasts were run once a day, initializing with the 0000 UTC dataset provided by NOAA (Forecast Systems Laboratory (FSL) <span class="hlt">Mesoscale</span> Analysis and Prediction System (MAPS)). In order to obtain better agreement with observations, a second set of simulations were done for the FIRE 2 cases that occurred on 25-26 Nov. and 5-6 Dec. In this set of simulations, a more complex radiation scheme was used, the Chen/Cotton radiation scheme, along with the nucleation of ice occurring at ice supersaturations as opposed to nucleation occurring at water supersaturations that was done in the actual forecast version. The runs using these more complex schemes took longer wall clock time (7-9 hours for the actual forecasts as compared to 12-14 hrs for the runs using the more complex schemes) however, the final results of the simulations were definitely improved upon. Comparisons between these two sets of simulations are given. Now underway are simulations of these cases using a closed analytical solution for the auto-conversion of ice from a pristine ice class (sizes less than about 50 microns in effective diameter) to a snow class (effective diameters on the order of several hundred microns). This solution is employed along with a new scheme for the nucleation of ice crystals due to Meyers et al and Demott et al. The scheme is derived assuming complete gamma distributions for both the pristine and snow classes. The time rate of change of the number concentration and mass mixing-ratio of each distribution is found by calculating either the flux of crystals that grow beyond a certain critical diameter by vapor deposition in an ice supersaturated regime or by calculating the flux of crystals that evaporate to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080030357&hterms=Hurricane+Katrina&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHurricane%2BKatrina','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080030357&hterms=Hurricane+Katrina&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHurricane%2BKatrina"><span id="translatedtitle">The Impact of Microphysics on Intensity and Structure of Hurricanes and <span class="hlt">Mesoscale</span> Convective Systems</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tao, Wei-Kuo; Shi, Jainn J.; Jou, Ben Jong-Dao; Lee, Wen-Chau; Lin, Pay-Liam; Chang, Mei-Yu</p> <p>2007-01-01</p> <p>During the past decade, both research and operational numerical weather prediction <span class="hlt">models</span>, e.g. Weather Research and Forecast (WRF) <span class="hlt">model</span>, have started using more complex microphysical schemes originally developed for high-resolution cloud resolving <span class="hlt">models</span> (CRMs) with a 1-2 km or less horizontal resolutions. WRF is a next-generation <span class="hlt">mesoscale</span> forecast <span class="hlt">model</span> and assimilation system that has incorporated modern software framework, advanced dynamics, numeric and data assimilation techniques, a multiple moveable <span class="hlt">nesting</span> capability, and improved physical packages. WRF <span class="hlt">model</span> can be used for a wide range of applications, from idealized research to operational forecasting, with an emphasis on horizontal grid sizes in the range of 1-10 km. The current WRF includes several different microphysics options such as Purdue Lin et al. (1983), WSM 6-class and Thompson microphysics schemes. We have recently implemented three sophisticated cloud microphysics schemes into WRF. The cloud microphysics schemes have been extensively tested and applied for different <span class="hlt">mesoscale</span> systems in different geographical locations. The performances of these schemes have been compared to those from other WRF microphysics options. We are performing sensitivity tests in using WRF to examine the impact of six different cloud microphysical schemes on precipitation processes associated hurricanes and <span class="hlt">mesoscale</span> convective systems developed at different geographic locations [Oklahoma (IHOP), Louisiana (Hurricane Katrina), Canada (C3VP - snow events), Washington (fire storm), India (Monsoon), Taiwan (TiMREX - terrain)]. We will determine the microphysical schemes for good simulated convective systems in these geographic locations. We are also performing the inline tracer calculation to comprehend the physical processes (i.e., boundary layer and each quadrant in the boundary layer) related to the development and structure of hurricanes and <span class="hlt">mesoscale</span> convective systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.7123P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.7123P"><span id="translatedtitle">Simulated response of the Southern Ocean to wind changes: towards the role of <span class="hlt">mesoscale</span> eddies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patara, Lavinia; Böning, Claus; Biastoch, Arne</p> <p>2013-04-01</p> <p>The role of ocean <span class="hlt">mesoscale</span> eddies in the Southern Ocean response to recent wind changes is explored with a suite of realistic global ocean simulations at increasing horizontal resolution. Southern Ocean <span class="hlt">mesoscale</span> eddies are known to be critical in the meridional redistribution of tracers, and are suggested to affect how the Southern Ocean responds to wind changes, takes up heat, and exchanges CO2 with the atmosphere. By employing the ocean general circulation <span class="hlt">model</span> NEMO-LIM, ocean simulations with horizontal resolutions of 1/2°, 1/4°, and 1/12°, i.e. ranging from non-eddying to eddy-resolving, are performed and compared. In particular, a "two-way" <span class="hlt">nesting</span> technique is used to refine the ocean grid up to 1/12° in the Southern Ocean. The ocean <span class="hlt">models</span> are forced with the CORE v.2 atmospheric reanalysis during the period 1948-2007, and companion experiments under a repeated-annual-cycle forcing are used to detect <span class="hlt">model</span> spurious drifts. First, we assess the effect of explicitly simulated eddies on ocean mean properties. <span class="hlt">Mesoscale</span> eddies are shown to modify the mixed layer depth and the upper-ocean density, with potential effects on the formation properties of Subantarctic Mode Waters. Second, we explore the role of <span class="hlt">mesoscale</span> eddies in affecting the ocean circulation sensitivity to the sustained increase of Southern Hemisphere winds during the past decades. Whereas the non-eddying simulations exhibit large increases of the Antarctic Circumpolar Current transport, the 1/4° and 1/12° <span class="hlt">models</span> are less sensitive to the wind increase, in better agreement with available observations. These results show a clear effect of <span class="hlt">model</span> resolution on the Southern Ocean response to climate variability and change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.9941B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.9941B"><span id="translatedtitle">Quantifying the effects of boundary condition uncertainty in <span class="hlt">nested</span> flood <span class="hlt">modelling</span> of complex hydraulic systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bermudez, Maria; Neal, Jeffrey C.; Bates, Paul D.; Coxon, Gemma; Freer, Jim E.; Cea, Luis; Puertas, Jeronimo</p> <p>2015-04-01</p> <p> through the city of Worcester (West Midlands, England), a flat subcritical reach in which backwater effects are significant. The flood event selected as a case study took place on the 20th July 2007 and is part of a series of destructive floods that occurred in the United Kingdom during that summer season. A full two-dimensional hydraulic <span class="hlt">model</span> with a high resolution grid is adopted at the local scale to resolve the complex urban flow field within Worcester, whereas a simpler representation of the flow processes that ignores convective acceleration has been selected for the regional <span class="hlt">model</span>. This <span class="hlt">nested</span> <span class="hlt">modelling</span> approach hence allows a continuous examination of the water fluxes from the catchment scale down to the reach and building scale, while still requiring reduced setup time and computational demand. Differences with measured water levels at benchmark stations and with flood extent from SAR images are used to evaluate the resulting prediction uncertainties. The results quantify how external forcing uncertainty propagates through flood inundation <span class="hlt">models</span> and affects <span class="hlt">model</span> predictions. This allows us to compare the relative importance of this uncertainty, often neglected in flood <span class="hlt">modelling</span>, with that of <span class="hlt">model</span> parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1692696','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1692696"><span id="translatedtitle">Parsimonious <span class="hlt">modelling</span> of water and suspended sediment flux from <span class="hlt">nested</span> catchments affected by selective tropical forestry.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Chappell, N A; McKenna, P; Bidin, K; Douglas, I; Walsh, R P</p> <p>1999-01-01</p> <p>The ability to <span class="hlt">model</span> the suspended sediment flux (SSflux) and associated water flow from terrain affected by selective logging is important to the establishment of credible measures to improve the ecological sustainability of forestry practices. Recent appreciation of the impact of parameter uncertainty on the statistical credibility of complex <span class="hlt">models</span> with little internal state validation supports the use of more parsimonious approaches such as data-based mechanistic (DBM) <span class="hlt">modelling</span>. The DBM approach combines physically based understanding with <span class="hlt">model</span> structure identification based on transfer functions and objective statistical inference. Within this study, these approaches have been newly applied to rainfall-SSflux response. The dynamics of the sediment system, together with the rainfall-river flow system, were monitored at five <span class="hlt">nested</span> contributory areas within a 44 ha headwater region in Malaysian Borneo. The data series analysed covered a whole year at a 5 min resolution, and were collected during a period some five to six years after selective timber harvesting had ceased. Physically based and statistical interpretation of these data was possible given the wealth of contemporary and past hydrogeomorphic data collected within the same region. The results indicated that parsimonious, three-parameter <span class="hlt">models</span> of rainfall-river flow and rainfall-SSflux for the whole catchment describe 80 and 90% of the variance, respectively, and that parameter changes between scales could be explained in physically meaningful terms. Indeed, the <span class="hlt">modelling</span> indicated some new conceptual descriptions of the river flow and sediment-generation systems. An extreme rainstorm having a 10-20 year return period was present within the data series and was shown to generate new mass movements along the forestry roads that had a differential impact on the monitored contributory areas. Critically, this spatially discrete behaviour was captured by the <span class="hlt">modelling</span> and may indicate the potential use of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA524888','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA524888"><span id="translatedtitle">CMS-Wave <span class="hlt">Model</span>: Part 3: Grid <span class="hlt">Nesting</span> and Application Example for Rhode Island South Shore Regional Sediment Management Study</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2010-07-01</p> <p>grid <span class="hlt">nesting</span> capability of the Coastal <span class="hlt">Modeling</span> System ( CMS ) wave <span class="hlt">model</span> CMS -Wave availa- ble in the U.S. Army Corps of Engineers (USACE) Surface-water...Martin, 2004). The motivation behind RISRSM is to identify the sediment pathways in a system at a regional scale for management of sediment based on...a system approach. The RISRSM is developing a management plan for sediments along the project study area that consists of a 38 km stretch of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/992747','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/992747"><span id="translatedtitle">Implementation and assessment of turbine wake <span class="hlt">models</span> in the Weather Research and Forecasting <span class="hlt">model</span> for both <span class="hlt">mesoscale</span> and large-eddy simulation</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Singer, M; Mirocha, J; Lundquist, J; Cleve, J</p> <p>2010-03-03</p> <p>Flow dynamics in large wind projects are influenced by the turbines located within. The turbine wakes, regions characterized by lower wind speeds and higher levels of turbulence than the surrounding free stream flow, can extend several rotor diameters downstream, and may meander and widen with increasing distance from the turbine. Turbine wakes can also reduce the power generated by downstream turbines and accelerate fatigue and damage to turbine components. An improved understanding of wake formation and transport within wind parks is essential for maximizing power output and increasing turbine lifespan. Moreover, the influence of wakes from large wind projects on neighboring wind farms, agricultural activities, and local climate are all areas of concern that can likewise be addressed by wake <span class="hlt">modeling</span>. This work describes the formulation and application of an actuator disk <span class="hlt">model</span> for studying flow dynamics of both individual turbines and arrays of turbines within wind projects. The actuator disk <span class="hlt">model</span> is implemented in the Weather Research and Forecasting (WRF) <span class="hlt">model</span>, which is an open-source atmospheric simulation code applicable to a wide range of scales, from <span class="hlt">mesoscale</span> to large-eddy simulation. Preliminary results demonstrate the applicability of the actuator disk <span class="hlt">model</span> within WRF to a moderately high-resolution large-eddy simulation study of a small array of turbines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1711564C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1711564C"><span id="translatedtitle">The Mediterranean overflow: New insights and numerical sensitivity from multiply <span class="hlt">nested</span> <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>Chanut, Jérôme; Benshila, Rachid; Debreu, Laurent; Masson, Sébastien</p> <p>2015-04-01</p> <p>In the past 20 years, ocean <span class="hlt">modellers</span> have paid much attention to either Gibraltar strait dynamics or Meddies formation, which are respectively at the origin and the end of the Mediterranean overflow descent in the Atlantic Ocean. Although the importance of topography is acknowledged on what happens in between, (i) the finest resolution in existing <span class="hlt">modelling</span> studies is still too coarse (o 2-6km) to properly capture main channels and canyons; (ii) results convergence relative to numerical settings has remained largely unexplored. Recent progress in the knowledge of the geological properties of the Gulf of Cadiz has indeed revealed the ubiquity of small scales bathymetry structures (o 1km) and a complex system of channels shaped by the Mediterranean Overflow (MO) currents. Taking advantage of a new high resolution bathymetry dataset, we present a refined view of MO splitting and spreading from semi-idealized numerical simulations. A multi grid, two-way <span class="hlt">nested</span> procedure is used to increase the horizontal resolution in key areas up to 250m, revealing the channelizing effect of bathymetry and the localized nature of mixing along MO pathways. The impact of vertical coordinate choice is investigated thanks to NEMO generalized vertical coordinate framework. The combination of geopotential and terrain following coordinates is shown to be the best compromise to faithfully represent the steep slopes bordering the basin, minimize pressure gradient errors and properly resolve bottom layers. Results with z-coordinates, as expected, perform relatively poorly leading to excessive entrainment. Sensitivity to vertical mixing schemes as well as horizontal resolution is also explored, providing an extensive set of experiments that complements similar studies in other overflow regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.C33B..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.C33B..02M"><span id="translatedtitle">Using <span class="hlt">Mesoscale</span> Atmospheric <span class="hlt">Models</span> for Glacio-Hydrological Studies at the Catchment Scale: Examples from High Asia and Perspectives for Future Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maussion, F.; Collier, S. E.</p> <p>2014-12-01</p> <p>In recent years, a new method has been developed to address the lack of in situ observations in remote, high-altitude glaciated catchments. With increases in computational resources and improvements in <span class="hlt">mesoscale</span> atmospheric <span class="hlt">models</span>, a small number of studies have shown that it is possible to simulate meteorological variables with sufficient spatial and temporal resolution for use as direct forcing for glacio-hydrological <span class="hlt">models</span> at the catchment scale. Based on the application of this method for atmospheric, glaciological and hydrological studies in High-Asian catchments, we present recommendations for key areas of uncertainty in the atmospheric <span class="hlt">modelling</span> strategy. We also identify a number of future research priorities based on several open questions related to <span class="hlt">model</span> resolution, feedbacks in the <span class="hlt">model</span> chain, and quantifying uncertainty where observations are absent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060013030&hterms=quantum+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dquantum%2Bmodel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060013030&hterms=quantum+model&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dquantum%2Bmodel"><span id="translatedtitle">The 0.125 degree finite-volume General Circulation <span class="hlt">Model</span> on the NASA Columbia Supercomputer: Preliminary Simulations of <span class="hlt">Mesoscale</span> Vortices</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shen, B.-W.; Atlas, R.; Chern, J.-D.; Reale, O.; Lin, S.-J.; Lee, T.; Chang, J.</p> <p>2005-01-01</p> <p>The NASA Columbia supercomputer was ranked second on the TOP500 List in November, 2004. Such a quantum jump in computing power provides unprecedented opportunities to conduct ultra-high resolution simulations with the finite-volume General Circulation <span class="hlt">Model</span> (fvGCM). During 2004, the <span class="hlt">model</span> was run in realtime experimentally at 0.25 degree resolution producing remarkable hurricane forecasts [Atlas et al., 2005]. In 2005, the horizontal resolution was further doubled, which makes the fvGCM comparable to the first <span class="hlt">mesoscale</span> resolving General Circulation <span class="hlt">Model</span> at the Earth Simulator Center [Ohfuchi et al., 2004]. Nine 5-day 0.125 degree simulations of three hurricanes in 2004 are presented first for <span class="hlt">model</span> validation. Then it is shown how the <span class="hlt">model</span> can simulate the formation of the Catalina eddies and Hawaiian lee vortices, which are generated by the interaction of the synoptic-scale flow with surface forcing, and have never been reproduced in a GCM before.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004PCE....29..725H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004PCE....29..725H"><span id="translatedtitle">Implementing river water quality <span class="hlt">modelling</span> issues in <span class="hlt">mesoscale</span> watershed <span class="hlt">models</span> for water policy demands??an overview on current concepts, deficits, and future tasks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horn, Andreas L.; Rueda, Francisco J.; Hörmann, Georg; Fohrer, Nicola</p> <p></p> <p>The political awareness of river water quality issues has increased substantially in the US and the EU during the last decade. New or enhanced environmental policies (e.g. European Union Water Framework Directive, US Total Maximum Daily Load Concept) require improved methods for investigation and evaluation of river water quality as well as derivation and assessment of management practices. Policy makers consider <span class="hlt">mesoscale</span> watershed <span class="hlt">models</span> as important support tools in this process if they provide the required functionality, i.e. they show capable of deriving reliable indicators for biological, hydromorphological and physico-chemical water quality. The aim of this study is to give an overview of the current state of integration of water quality issues in watershed <span class="hlt">models</span> and the application experience with the approaches. It is pointed out that the suitability of current <span class="hlt">models</span> for the projected tasks is limited. Some of the <span class="hlt">models</span> do not have water quality routines, and for those that have respective routines integrated there often exists minor application experience and the range of available water quality parameters is insufficient. Increasing efforts regarding the integration of river water quality issues in watershed <span class="hlt">models</span> and more contributions to the application experience of these <span class="hlt">models</span> are therefore recommended. In particular, watershed <span class="hlt">modellers</span> will have to develop tools capable of linking physico-chemical variables already predicted by present watershed <span class="hlt">models</span> with additional hydromorphological and biological quality elements demanded by policy programs such as EU-WFD. It is outlined that the derivation of expert systems instead of process-based <span class="hlt">model</span> routines should be considered for the purpose of relating abiotic and biotic quality elements. Expert systems are expected to limit the increase of <span class="hlt">model</span> complexity, which inevitably occurs in the course of <span class="hlt">model</span> extension. Habitat evaluation procedures used in impact assessment and current river</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AIPC.1450..147W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AIPC.1450..147W"><span id="translatedtitle"><span class="hlt">Nested</span> generalized linear mixed <span class="hlt">model</span> with ordinal response: Simulation and application on poverty data in Java Island</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Widyaningsih, Yekti; Saefuddin, Asep; Notodiputro, Khairil A.; Wigena, Aji H.</p> <p>2012-05-01</p> <p>The objective of this research is to build a <span class="hlt">nested</span> generalized linear mixed <span class="hlt">model</span> using an ordinal response variable with some covariates. There are three main jobs in this paper, i.e. parameters estimation procedure, simulation, and implementation of the <span class="hlt">model</span> for the real data. At the part of parameters estimation procedure, concepts of threshold, <span class="hlt">nested</span> random effect, and computational algorithm are described. The simulations data are built for 3 conditions to know the effect of different parameter values of random effect distributions. The last job is the implementation of the <span class="hlt">model</span> for the data about poverty in 9 districts of Java Island. The districts are Kuningan, Karawang, and Majalengka chose randomly in West Java; Temanggung, Boyolali, and Cilacap from Central Java; and Blitar, Ngawi, and Jember from East Java. The covariates in this <span class="hlt">model</span> are province, number of bad nutrition cases, number of farmer families, and number of health personnel. In this <span class="hlt">modeling</span>, all covariates are grouped as ordinal scale. Unit observation in this research is sub-district (kecamatan) <span class="hlt">nested</span> in district, and districts (kabupaten) are <span class="hlt">nested</span> in province. For the result of simulation, ARB (Absolute Relative Bias) and RRMSE (Relative Root of mean square errors) scale is used. They show that prov parameters have the highest bias, but more stable RRMSE in all conditions. The simulation design needs to be improved by adding other condition, such as higher correlation between covariates. Furthermore, as the result of the <span class="hlt">model</span> implementation for the data, only number of farmer family and number of medical personnel have significant contributions to the level of poverty in Central Java and East Java province, and only district 2 (Karawang) of province 1 (West Java) has different random effect from the others. The source of the data is PODES (Potensi Desa) 2008 from BPS (Badan Pusat Statistik).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AdG....31...15K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AdG....31...15K"><span id="translatedtitle">Regionalization of <span class="hlt">meso-scale</span> physically based nitrogen <span class="hlt">modeling</span> outputs to the macro-scale by the use of regression trees</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Künne, A.; Fink, M.; Kipka, H.; Krause, P.; Flügel, W.-A.</p> <p>2012-06-01</p> <p>In this paper, a method is presented to estimate excess nitrogen on large scales considering single field processes. The approach was implemented by using the physically based <span class="hlt">model</span> J2000-S to simulate the nitrogen balance as well as the hydrological dynamics within <span class="hlt">meso-scale</span> test catchments. The <span class="hlt">model</span> input data, the parameterization, the results and a detailed system understanding were used to generate the regression tree <span class="hlt">models</span> with GUIDE (Loh, 2002). For each landscape type in the federal state of Thuringia a regression tree was calibrated and validated using the <span class="hlt">model</span> data and results of excess nitrogen from the test catchments. Hydrological parameters such as precipitation and evapotranspiration were also used to predict excess nitrogen by the regression tree <span class="hlt">model</span>. Hence they had to be calculated and regionalized as well for the state of Thuringia. Here the <span class="hlt">model</span> J2000g was used to simulate the water balance on the macro scale. With the regression trees the excess nitrogen was regionalized for each landscape type of Thuringia. The approach allows calculating the potential nitrogen input into the streams of the drainage area. The results show that the applied methodology was able to transfer the detailed <span class="hlt">model</span> results of the <span class="hlt">meso-scale</span> catchments to the entire state of Thuringia by low computing time without losing the detailed knowledge from the nitrogen transport <span class="hlt">modeling</span>. This was validated with <span class="hlt">modeling</span> results from Fink (2004) in a catchment lying in the regionalization area. The regionalized and <span class="hlt">modeled</span> excess nitrogen correspond with 94%. The study was conducted within the framework of a project in collaboration with the Thuringian Environmental Ministry, whose overall aim was to assess the effect of agro-environmental measures regarding load reduction in the water bodies of Thuringia to fulfill the requirements of the European Water Framework Directive (Bäse et al., 2007; Fink, 2006; Fink et al., 2007).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24815341','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24815341"><span id="translatedtitle">Spatial analysis of toxic emissions in LCA: a sub-continental <span class="hlt">nested</span> USEtox <span class="hlt">model</span> with freshwater archetypes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kounina, Anna; Margni, Manuele; Shaked, Shanna; Bulle, Cécile; Jolliet, Olivier</p> <p>2014-08-01</p> <p>This paper develops continent-specific factors for the USEtox <span class="hlt">model</span> and analyses the accuracy of different <span class="hlt">model</span> architectures, spatial scales and archetypes in evaluating toxic impacts, with a focus on freshwater pathways. Inter-continental variation is analysed by comparing chemical fate and intake fractions between sub-continental zones of two life cycle impact assessment <span class="hlt">models</span>: (1) the <span class="hlt">nested</span> USEtox <span class="hlt">model</span> parameterized with sub-continental zones and (2) the spatially differentiated IMPACTWorld <span class="hlt">model</span> with 17 interconnected sub-continental regions. Substance residence time in water varies by up to two orders of magnitude among the 17 zones assessed with IMPACTWorld and USEtox, and intake fraction varies by up to three orders of magnitude. Despite this variation, the <span class="hlt">nested</span> USEtox <span class="hlt">model</span> succeeds in mimicking the results of the spatially differentiated <span class="hlt">model</span>, with the exception of very persistent volatile pollutants that can be transported to polar regions. Intra-continental variation is analysed by comparing fate and intake fractions <span class="hlt">modelled</span> with the a-spatial (one box) IMPACT Europe continental <span class="hlt">model</span> vs. the spatially differentiated version of the same <span class="hlt">model</span>. Results show that the one box <span class="hlt">model</span> might overestimate chemical fate and characterisation factors for freshwater eco-toxicity of persistent pollutants by up to three orders of magnitude for point source emissions. Subdividing Europe into three archetypes, based on freshwater residence time (how long it takes water to reach the sea), improves the prediction of fate and intake fractions for point source emissions, bringing them within a factor five compared to the spatial <span class="hlt">model</span>. We demonstrated that a sub-continental <span class="hlt">nested</span> <span class="hlt">model</span> such as USEtox, with continent-specific parameterization complemented with freshwater archetypes, can thus represent inter- and intra-continental spatial variations, whilst minimizing <span class="hlt">model</span> complexity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2864735','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2864735"><span id="translatedtitle">3-D <span class="hlt">Modelling</span> of Megaloolithid Clutches: Insights about <span class="hlt">Nest</span> Construction and Dinosaur Behaviour</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Vila, Bernat; Jackson, Frankie D.; Fortuny, Josep; Sellés, Albert G.; Galobart, Àngel</p> <p>2010-01-01</p> <p>Background Megaloolithid eggs have long been associated with sauropod dinosaurs. Despite their extensive and worldwide fossil record, interpretations of egg size and shape, clutch morphology, and incubation strategy vary. The Pinyes locality in the Upper Cretaceous Tremp Formation in the southern Pyrenees, Catalonia provides new information for addressing these issues. Nine horizons containing Megaloolithus siruguei clutches are exposed near the village of Coll de Nargó. Tectonic deformation in the study area strongly influenced egg size and shape, which could potentially lead to misinterpretation of reproductive biology if 2D and 3D maps are not corrected for bed dip that results from tectonism. Methodology/Findings Detailed taphonomic study and three-dimensional <span class="hlt">modelling</span> of fossil eggs show that intact M. siruguei clutches contained 20–28 eggs, which is substantially larger than commonly reported from Europe and India. Linear and grouped eggs occur in three superimposed levels and form an asymmetric, elongate, bowl-shaped profile in lateral view. Computed tomography data support previous interpretations that the eggs hatched within the substrate. Megaloolithid clutch sizes reported from other European and Indian localities are typically less than 15 eggs; however, these clutches often include linear or grouped eggs that resemble those of the larger Pinyes clutches and may reflect preservation of incomplete clutches. Conclusions/Significance We propose that 25 eggs represent a typical megaloolithid clutch size and smaller egg clusters that display linear or grouped egg arrangements reported at Pinyes and other localities may represent eroded remnants of larger clutches. The similarity of megaloolithid clutch morphology from localities worldwide strongly suggests common reproductive behaviour. The distinct clutch geometry at Pinyes and other localities likely resulted from the asymmetrical, inclined, and laterally compressed titanosaur pes unguals of the female</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25992956','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25992956"><span id="translatedtitle">Evaluation of trail-cameras for analyzing the diet of <span class="hlt">nesting</span> raptors using the Northern Goshawk as a <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>García-Salgado, Gonzalo; Rebollo, Salvador; Pérez-Camacho, Lorenzo; Martínez-Hesterkamp, Sara; Navarro, Alberto; Fernández-Pereira, José-Manuel</p> <p>2015-01-01</p> <p>Diet studies present numerous methodological challenges. We evaluated the usefulness of commercially available trail-cameras for analyzing the diet of Northern Goshawks (Accipiter gentilis) as a <span class="hlt">model</span> for <span class="hlt">nesting</span> raptors during the period 2007-2011. We compared diet estimates obtained by direct camera monitoring of 80 <span class="hlt">nests</span> with four indirect analyses of prey remains collected from the <span class="hlt">nests</span> and surroundings (pellets, bones, feather-and-hair remains, and feather-hair-and-bone remains combined). In addition, we evaluated the performance of the trail-cameras and whether camera monitoring affected Goshawk behavior. The sensitivity of each diet-analysis method depended on prey size and taxonomic group, with no method providing unbiased estimates for all prey sizes and types. The cameras registered the greatest number of prey items and were probably the least biased method for estimating diet composition. Nevertheless this direct method yielded the largest proportion of prey unidentified to species level, and it underestimated small prey. Our trail-camera system was able to operate without maintenance for longer periods than what has been reported in previous studies with other types of cameras. Initially Goshawks showed distrust toward the cameras but they usually became habituated to its presence within 1-2 days. The habituation period was shorter for breeding pairs that had previous experience with cameras. Using trail-cameras to monitor prey provisioning to <span class="hlt">nests</span> is an effective tool for studying the diet of <span class="hlt">nesting</span> raptors. However, the technique is limited by technical failures and difficulties in identifying certain prey types. Our study also shows that cameras can alter adult Goshawk behavior, an aspect that must be controlled to minimize potential negative impacts.</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://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4438871','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4438871"><span id="translatedtitle">Evaluation of Trail-Cameras for Analyzing the Diet of <span class="hlt">Nesting</span> Raptors Using the Northern Goshawk as a <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>García-Salgado, Gonzalo; Rebollo, Salvador; Pérez-Camacho, Lorenzo; Martínez-Hesterkamp, Sara; Navarro, Alberto; Fernández-Pereira, José-Manuel</p> <p>2015-01-01</p> <p>Diet studies present numerous methodological challenges. We evaluated the usefulness of commercially available trail-cameras for analyzing the diet of Northern Goshawks (Accipiter gentilis) as a <span class="hlt">model</span> for <span class="hlt">nesting</span> raptors during the period 2007–2011. We compared diet estimates obtained by direct camera monitoring of 80 <span class="hlt">nests</span> with four indirect analyses of prey remains collected from the <span class="hlt">nests</span> and surroundings (pellets, bones, feather-and-hair remains, and feather-hair-and-bone remains combined). In addition, we evaluated the performance of the trail-cameras and whether camera monitoring affected Goshawk behavior. The sensitivity of each diet-analysis method depended on prey size and taxonomic group, with no method providing unbiased estimates for all prey sizes and types. The cameras registered the greatest number of prey items and were probably the least biased method for estimating diet composition. Nevertheless this direct method yielded the largest proportion of prey unidentified to species level, and it underestimated small prey. Our trail-camera system was able to operate without maintenance for longer periods than what has been reported in previous studies with other types of cameras. Initially Goshawks showed distrust toward the cameras but they usually became habituated to its presence within 1–2 days. The habituation period was shorter for breeding pairs that had previous experience with cameras. Using trail-cameras to monitor prey provisioning to <span class="hlt">nests</span> is an effective tool for studying the diet of <span class="hlt">nesting</span> raptors. However, the technique is limited by technical failures and difficulties in identifying certain prey types. Our study also shows that cameras can alter adult Goshawk behavior, an aspect that must be controlled to minimize potential negative impacts. PMID:25992956</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008OcMod..23..113E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008OcMod..23..113E"><span id="translatedtitle">Diapycnal mixing by <span class="hlt">meso-scale</span> eddies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eden, Carsten; Greatbatch, Richard J.</p> <p></p> <p>The mean available potential energy released by baroclinic instability into the <span class="hlt">meso-scale</span> eddy field has to be dissipated in some way and Tandon and Garrett [Tandon, A., Garrett, C., 1996. On a recent parameterization of <span class="hlt">mesoscale</span> eddies. J. Phys. Oceanogr. 26 (3), 406-416] suggested that this dissipation could ultimately involve irreversible mixing of buoyancy by molecular processes at the small-scale end of the turbulence cascade. We revisit this idea and argue that the presence of dissipation within the thermocline automatically requires that a component of the eddy flux associated with <span class="hlt">meso-scale</span> eddies must be associated with irreversible mixing of buoyancy within the thermocline. We offer a parameterisation of the implied diapycnal diffusivity based on (i) the dissipation rate for eddy kinetic energy given by the <span class="hlt">meso-scale</span> eddy closure of Eden and Greatbatch [Eden, C., Greatbatch, R.J., 2008. Towards a <span class="hlt">meso-scale</span> eddy closure. Ocean <span class="hlt">Modell</span>. 20, 223-239.] and (ii) a fixed mixing efficiency. The implied eddy-induced diapycnal diffusivity ( κ) is implemented in a coarse resolution <span class="hlt">model</span> of the North Atlantic. In contrast to the vertical diffusivity given by a standard vertical mixing scheme, large lateral inhomogeneities can be found for κ in the interior of the ocean. In general, κ is large, i.e. up to o(10) cm 2/s, near the western boundaries and almost vanishing in the interior of the ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED551064.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED551064.pdf"><span id="translatedtitle">A Primer for Analyzing <span class="hlt">Nested</span> Data: Multilevel <span class="hlt">Modeling</span> in SPSS Using an Example from a REL Study. REL 2015-046</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>O'Dwyer, Laura M.; Parker, Caroline E.</p> <p>2014-01-01</p> <p>Analyzing data that possess some form of <span class="hlt">nesting</span> is often challenging for applied researchers or district staff who are involved in or in charge of conducting data analyses. This report provides a description of the challenges for analyzing <span class="hlt">nested</span> data and provides a primer of how multilevel regression <span class="hlt">modeling</span> may be used to resolve these…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC13J0812F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC13J0812F"><span id="translatedtitle">Assessing Climatic Impacts due to Land Use Change over Southeast Asian Maritime Continent base on <span class="hlt">Mesoscale</span> <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>Feng, N.; Christopher, S. A.; Nair, U. S.</p> <p>2014-12-01</p> <p>Due to increasing urbanization, deforestation, and agriculture, land use change over Southeast Asia has dramatically risen during the last decades. Large areas of peat swamp forests over the Southeast Asian Maritime Continent region (10°S~20°N and 90°E~135°E) have been cleared for agricultural purposes. The Center for Remote Imaging, Sensing and Processing (CRISP) Moderate Resolution Imaging Spectroradiometer (MODIS) derived land cover classification data show that changes in land use are dominated by conversion of peat swamp forests to oil palm plantation, open lowland or lowland mosaic categories. <span class="hlt">Nested</span> grid simulations based on Weather Research Forecasting Version 3.6 <span class="hlt">modelling</span> system (WRFV3.6) over the central region of the Sarawak coast are used to investigate the climatic impacts of land use change over Maritime Continent. Numerical simulations were conducted for August of 2009 for satellite derived land cover scenarios for years 2000 and 2010. The variations in cloud formation, precipitation, and regional radiative and non-radiative parameters on climate results from land use change have been assessed based on numerical simulation results. <span class="hlt">Modelling</span> studies demonstrate that land use change such as extensive deforestation processes can produce a negative radiative forcing due to the surface albedo increase and evapotranspiration decrease, while also largely caused reduced rainfall and cloud formation, and enhanced shortwave radiative forcing and temperature over the study area. Land use and land cover changes, similar to the domain in this study, has also occurred over other regions in Southeast Asia including Indonesia and could also impact cloud and precipitation formation in these regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA630760','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA630760"><span id="translatedtitle">Optimizing Scrum <span class="hlt">Mesoscale</span> Eddy Forecasts</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2016-06-07</p> <p>complementary to the Kalman filter techniques being developed by Rutgers scientists. Our long-term scientific goal is to <span class="hlt">model</span> and predict the <span class="hlt">mesoscale</span>...NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS...adjoint-ready". The code resulting from the adjoint compiler must be further modified by hand to make it work . It will also need to be tested against the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA628369','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA628369"><span id="translatedtitle">Practical Limits to Atmospheric <span class="hlt">Mesoscale</span> Predictability</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2002-09-30</p> <p>is to run a series of numerical <span class="hlt">model</span> experiments using different data assimilation methods and the same observational samples and determine the...Miller, 2002: Landfalling cyclone forecast sensitivity to varying data assimilation methods in a <span class="hlt">mesoscale</span> <span class="hlt">model</span>. Preprints of 10th Conference on Mountain Meteorology, Park City, UT, June 17-21, 2002</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18939781','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18939781"><span id="translatedtitle">Evaluation of the <span class="hlt">Mesoscale</span> Meteorological <span class="hlt">Model</span> (MM5)-Community Multi-Scale Air Quality <span class="hlt">Model</span> (CMAQ) performance in hindcast and forecast of ground-level ozone.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nghiem, Le Hoang; Kim Oanh, Nguyen Thi</p> <p>2008-10-01</p> <p>This paper presents the first attempt to apply the <span class="hlt">Mesoscale</span> Meteorological <span class="hlt">Model</span> (MM5)-Community Multi-Scale Air Quality <span class="hlt">Model</span> (CMAQ) <span class="hlt">model</span> system to simulate ground-level ozone (O3) over the continental Southeast Asia (CSEA) region for both hindcast and forecast purposes. Hindcast simulation was done over the CSEA domain for two historical O3 episodes, January 26-29, 2004 (January episode, northeast monsoon) and March 24-26, 2004 (March episode, southwest monsoon). Experimental forecast was done for next-day hourly O3 during January 2006 over the central part of Thailand (CENTHAI). Available data from 20 ambient monitoring stations in Thailand and 3 stations in Ho Chi Minh City, Vietnam, were used for the episode analysis and for the <span class="hlt">model</span> performance evaluation. The year 2000 anthropogenic emission inventory prepared by the Center for Global and Regional Environmental Research at the University of Iowa was projected to the simulation year on the basis of the regional average economic growth rate. Hourly emission in urban areas was prepared using ambient carbon monoxide concentration as a surrogate for the emission intensity. Biogenic emissions were estimated based on data from the Global Emissions Inventory Activity. Hindcast simulations (CSEA) were performed with 0.5 degree x 0.5 degree resolution, whereas forecast simulations (CENTHAI) were done with 0.1 degree x 0.1 degree hourly emission input data. MM5-CMAQ <span class="hlt">model</span> system performance during the selected episodes satisfactorily met U.S. Environmental Protection Agency criteria for O3 for most simulated days. The experiment forecast for next-day hourly O3 in January 2006 yielded promising results. <span class="hlt">Modeled</span> plumes of ozone in both hindcast and forecast cases agreed with the main wind fields and extended over considerable downwind distances from large urban areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC33A0495P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC33A0495P"><span id="translatedtitle">A 7-km Non-Hydrostatic Global <span class="hlt">Mesoscale</span> Simulation with the Goddard Earth Observing System <span class="hlt">Model</span> (GEOS-5) for Observing System Simulation Experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Putman, W.; Suarez, M.; Gelaro, R.; daSilva, A.; Molod, A.; Ott, L. E.; Darmenov, A.</p> <p>2014-12-01</p> <p>The Global <span class="hlt">Modeling</span> and Assimilation Office at NASA Goddard Space Flight Center has used the Goddard Earth Observing System <span class="hlt">model</span> (GEOS-5) to produce a 2-year non-hydrostatic global <span class="hlt">mesoscale</span> simulation for the period of June 2005-2007. This 7-km GEOS-5 Nature Run (7km-G5NR) product will provide synthetic observations for observing system simulation experiments (OSSE)s at NASA and NOAA through the Joint Center for Satellite Data Assimilation and the NASA Center for Climate Simulation. While GEOS-5 is regularly applied in seasonal-to-decadal climate simulations, and medium range weather prediction and data assimilation, GEOS-5 is also readily adaptable for application as a global <span class="hlt">mesoscale</span> <span class="hlt">model</span> in pursuit of global cloud resolving applications. Recent computing advances have permitted experimentation with global atmospheric <span class="hlt">models</span> at these scales, although production applications like the 7km-G5NR have remained limited. By incorporating a non-hydrostatic finite-volume dynamical core with scale aware physics parameterizations, the 7km-G5NR produces organized convective systems and robust weather systems ideal for producing observations for existing and new remote sensing instruments. In addition to standard meteorological parameters, the 7km-G5NR includes 15 aerosol tracers (including dust, seasalt, sulfate, black and organic carbon), O3, CO and CO2. The 7km-G5NR is driven by prescribed sea-surface temperatures and sea-ice, daily volcanic and biomass burning emissions, as well as high-resolution inventories of anthropogenic sources. We will discuss the technical challenges of producing the 7km-G5NR including the nearly 5 petabytes of full resolution output at 30-minute intervals as required by the OSSE developers, and modifications to the standard GEOS-5 physics to permit convective organization at the 'grey-zone' resolution of 7km. Highlights of the 7km-G5NR validation will focus on the representation of clouds and organized convection including tropical cyclones</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ems..confE..76S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ems..confE..76S"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Analysis and <span class="hlt">Modeling</span> of a Severe Thunderstorm and its Interaction with Foehn-dried Air at the Northern Alpine Slope.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stoll, M.; Leuenberger, D.</p> <p>2010-09-01</p> <p>Severe convection ist one of the most challenging meteorological phenomena not only for numerical <span class="hlt">modeling</span> but also for routine forecast operations and warning procedures. On 23rd Juli 2009 a severe rightmoving supercell storm moved across the whole west-east extent of the northern Swiss alpine slope and adjacent areas on the plateau, causing widespread hail and wind damage. In this case study the <span class="hlt">mesoscale</span> storm structure is investigated using both observational data as well as numerical simulations from the operational Swiss COSMO-<span class="hlt">model</span> suite. Special emphasis is put on a specific phase of the storm's life cycle, when it moved from an environment characterized by warm and moist boundary layer air into an area of Foehn-influenced, dry and hot air confined within the alpine valleys.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApCM..tmp...91Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApCM..tmp...91Z"><span id="translatedtitle">Finite Element Analysis of Warp-Reinforced 2.5D Woven Composites Based on a <span class="hlt">Meso-Scale</span> Voxel <span class="hlt">Model</span> under Compression Loading</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Diantang; Chen, Li; Wang, Yanjie; Sun, Ying; Jia, Na; Qian, Kun</p> <p>2016-11-01</p> <p>A study is conducted with the aim of developing <span class="hlt">meso-scale</span> voxel-based <span class="hlt">model</span> for evaluating the compressive behaviors of warp-reinforced 2.5D woven composites. The real microstructure of warp-reinforced 2.5D woven composites is established. For the validation of this <span class="hlt">model</span>, a series of axial (warp direction) and transverse (weft direction) compressive tests are conducted. The results show that under axial and transverse compressive loading, the calculated max stress and the final damage morphology agree well with the experimental results. Moreover, it is found that the axial compressive strength is mainly dependent on the high-crimp blinder warp, while the transverse compressive strength is significantly influenced by the warp/weft interlaced regions. It is expected that such a numerical investigation will provide useful information for understanding the strength and failure characteristic of 2.5D woven composites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25449735','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25449735"><span id="translatedtitle">Survival analysis of clinical mastitis data using a <span class="hlt">nested</span> frailty Cox <span class="hlt">model</span> fit as a mixed-effects Poisson <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>Elghafghuf, Adel; Dufour, Simon; Reyher, Kristen; Dohoo, Ian; Stryhn, Henrik</p> <p>2014-12-01</p> <p>Mastitis is a complex disease affecting dairy cows and is considered to be the most costly disease of dairy herds. The hazard of mastitis is a function of many factors, both managerial and environmental, making its control a difficult issue to milk producers. Observational studies of clinical mastitis (CM) often generate datasets with a number of characteristics which influence the analysis of those data: the outcome of interest may be the time to occurrence of a case of mastitis, predictors may change over time (time-dependent predictors), the effects of factors may change over time (time-dependent effects), there are usually multiple hierarchical levels, and datasets may be very large. Analysis of such data often requires expansion of the data into the counting-process format - leading to larger datasets - thus complicating the analysis and requiring excessive computing time. In this study, a <span class="hlt">nested</span> frailty Cox <span class="hlt">model</span> with time-dependent predictors and effects was applied to Canadian Bovine Mastitis Research Network data in which 10,831 lactations of 8035 cows from 69 herds were followed through lactation until the first occurrence of CM. The <span class="hlt">model</span> was fit to the data as a Poisson <span class="hlt">model</span> with <span class="hlt">nested</span> normally distributed random effects at the cow and herd levels. Risk factors associated with the hazard of CM during the lactation were identified, such as parity, calving season, herd somatic cell score, pasture access, fore-stripping, and proportion of treated cases of CM in a herd. The analysis showed that most of the predictors had a strong effect early in lactation and also demonstrated substantial variation in the baseline hazard among cows and between herds. A small simulation study for a setting similar to the real data was conducted to evaluate the Poisson maximum likelihood estimation approach with both Gaussian quadrature method and Laplace approximation. Further, the performance of the two methods was compared with the performance of a widely used estimation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26587252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26587252"><span id="translatedtitle">Reduced entomopathogen abundance in Myrmica ant <span class="hlt">nests</span>-testing a possible immunological benefit of myrmecophily using Galleria mellonella as a <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>Schär, Sämi; Larsen, Louise L M; Meyling, Nicolai V; Nash, David R</p> <p>2015-10-01</p> <p>Social insects such as ants have evolved collective rather than individual immune defence strategies against diseases and parasites at the level of their societies (colonies), known as social immunity. Ants frequently host other arthropods, so-called myrmecophiles, in their <span class="hlt">nests</span>. Here, we tested the hypothesis that myrmecophily may partly arise from selection for exploiting the ants' social immunity. We used larvae of the wax moth Galleria mellonella as '<span class="hlt">model</span> myrmecophiles' (baits) to test this hypothesis. We found significantly reduced abundance of entomopathogens in ant <span class="hlt">nests</span> compared with the surrounding environment. Specific entomopathogen groups (Isaria fumosorosea and nematodes) were also found to be significantly less abundant inside than outside ant <span class="hlt">nests</span>, whereas one entomopathogen (Beauveria brongniartii) was significantly more abundant inside <span class="hlt">nests</span>. We therefore hypothesize that immunological benefits of entering ant <span class="hlt">nests</span> may provide us a new explanation of why natural selection acts in favour of such a life-history strategy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830017046','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830017046"><span id="translatedtitle">Evaluation of the synoptic and <span class="hlt">mesoscale</span> predictive capabilities of a <span class="hlt">mesoscale</span> atmospheric simulation system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Koch, S. E.; Skillman, W. C.; Kocin, P. J.; Wetzel, P. J.; Brill, K.; Keyser, D. A.; Mccumber, M. C.</p> <p>1983-01-01</p> <p>The overall performance characteristics of a limited area, hydrostatic, fine (52 km) mesh, primitive equation, numerical weather prediction <span class="hlt">model</span> are determined in anticipation of satellite data assimilations with the <span class="hlt">model</span>. The synoptic and <span class="hlt">mesoscale</span> predictive capabilities of version 2.0 of this <span class="hlt">model</span>, the <span class="hlt">Mesoscale</span> Atmospheric Simulation System (MASS 2.0), were evaluated. The two part study is based on a sample of approximately thirty 12h and 24h forecasts of atmospheric flow patterns during spring and early summer. The synoptic scale evaluation results benchmark the performance of MASS 2.0 against that of an operational, synoptic scale weather prediction <span class="hlt">model</span>, the Limited area Fine Mesh (LFM). The large sample allows for the calculation of statistically significant measures of forecast accuracy and the determination of systematic <span class="hlt">model</span> errors. The synoptic scale benchmark is required before unsmoothed <span class="hlt">mesoscale</span> forecast fields can be seriously considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26097744','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26097744"><span id="translatedtitle">A daily global <span class="hlt">mesoscale</span> ocean eddy dataset from satellite altimetry.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Faghmous, James H; Frenger, Ivy; Yao, Yuanshun; Warmka, Robert; Lindell, Aron; Kumar, Vipin</p> <p>2015-01-01</p> <p><span class="hlt">Mesoscale</span> ocean eddies are ubiquitous coherent rotating structures of water with radial scales on the order of 100 kilometers. Eddies play a key role in the transport and mixing of momentum and tracers across the World Ocean. We present a global daily <span class="hlt">mesoscale</span> ocean eddy dataset that contains ~45 million <span class="hlt">mesoscale</span> features and 3.3 million eddy trajectories that persist at least two days as identified in the AVISO dataset over a period of 1993-2014. This dataset, along with the open-source eddy identification software, extract eddies with any parameters (minimum size, lifetime, etc.), to study global eddy properties and dynamics, and to empirically estimate the impact eddies have on mass or heat transport. Furthermore, our open-source software may be used to identify <span class="hlt">mesoscale</span> features in <span class="hlt">model</span> simulations and compare them to observed features. Finally, this dataset can be used to study the interaction between <span class="hlt">mesoscale</span> ocean eddies and other components of the Earth System.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1104951','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1104951"><span id="translatedtitle">Use of ARM observations and numerical <span class="hlt">models</span> to determine radiative and latent heating profiles of <span class="hlt">mesoscale</span> convective systems for general circulation <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Robert A. Houze, Jr.</p> <p>2013-11-13</p> <p>We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical <span class="hlt">model</span> by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) <span class="hlt">mesoscale</span> <span class="hlt">model</span> at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving <span class="hlt">model</span> forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890035621&hterms=assimilation+procedure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dassimilation%2Bprocedure','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890035621&hterms=assimilation+procedure&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dassimilation%2Bprocedure"><span id="translatedtitle">Use of four-dimensional data assimilation by Newtonian relaxation and latent-heat forcing to improve a <span class="hlt">mesoscale-model</span> precipitation forecast - A case study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Wei; Warner, Thomas T.</p> <p>1988-01-01</p> <p>The Penn State/NCAR <span class="hlt">mesoscale</span> <span class="hlt">model</span> was used to study special static-initialization (SI) and dynamic-initialization (DI) techniques designed to improve short-range quantitative precipitation forecasts (QPFs), as applied to the heavy convective rainfall that occurred in Texas, Oklahoma, and Kansas during the May 9-10, 1979 SESAMY IV study period. In the DI procedure, two types of four-dimensional data assimilation (FDDA) procedures were used to incorporate data during a 12-h preforecast period, one using the Newtonian relaxation, the other using latent-heat forcing. It was found that combined use of either the preforecast or in-forecast latent-heat forcing with the Newtonian relaxation produced an improved forecast (relative to a conventional forecast procedure) of rainfall intensity compared to the use of the Newtonian relaxation alone. The use of the experimental SI with prescribed latent heating during the first forecast hour produced greatly improved rainfall rates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020061380','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020061380"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Convective Systems During SCSMEX: Simulations with a Regional Climate <span class="hlt">Model</span> and a Cloud-Resolving <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>Tao, W. K.; Wang, Y.; Qian, J.; Shie, C. -L.; Lau, W. K. -M.; Kakar, R.; Starr, David O' C. (Technical Monitor)</p> <p>2002-01-01</p> <p>The South China Sea Monsoon Experiment (SCSMEX) was conducted in May-June 1998. One of its major objectives is to better understand the key physical processes for the onset and evolution of the summer monsoon over Southeast Asia and southern China (Lau et al. 2000). Multiple observation platforms (e.g., soundings, Doppler radar, ships, wind seafarers, radiometers, etc.) during SCSMEX provided a first attempt at investigating the detailed characteristics of convection and circulation changes, associated with monsoons over the South China Sea region. SCSMEX also provided precipitation derived from atmospheric budgets (Johnson and Ciesielski 2002) and comparison to those obtained from the Tropical Rainfall Measuring Mission (TRMM). In this paper, a regional climate <span class="hlt">model</span> and a cloud-resolving <span class="hlt">model</span> are used to perform multi-day integrations to understand the precipitation processes associated with the summer monsoon over Southeast Asia and southern China. The regional climate <span class="hlt">model</span> is used to understand the soil - precipitation interaction and feedback associated with a flood event that occurred in and around China's Atlantic River during SCSMEX. Sensitivity tests on various land surface <span class="hlt">models</span>, cumulus parameterization schemes (CASE), sea surface temperature (SST) variations and midlatitude influences are also performed to understand the processes associated with the onset of the monsoon over the S. China Sea during SCSMEX. Cloud-resolving <span class="hlt">models</span> (CRMs) use more sophisticated and physically realistic parameterizations of cloud microphysical processes with very fine spatial and temporal resolution. One of the major characteristics of CRMs is an explicit interaction between clouds, radiation and the land/ocean surface. It is for this reason that GEWEX (Global Energy and Water Cycle Experiment) has formed the GCSS (GEWEX Cloud System Study) expressly for the purpose of improving the representation of the moist processes in large-scale <span class="hlt">models</span> using CRMs. The Goddard</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020081020&hterms=climate+change+impact+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dclimate%2Bchange%2Bimpact%2Bocean','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020081020&hterms=climate+change+impact+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dclimate%2Bchange%2Bimpact%2Bocean"><span id="translatedtitle"><span class="hlt">Mesoscale</span> Convective Systems During SCSMEX: Simulations with a Regional Climate <span class="hlt">Model</span> and a Cloud-Resolving <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>Tao, W.-K.; Wang, Y.; Qian, J.-H.; Shie, C.-L.; Lau, W. K.-M.; Kakar, R.; Starr, David (Technical Monitor)</p> <p>2002-01-01</p> <p>The South China Sea Monsoon Experiment (SCSMEX) was conducted in May-June 1998. One of its major objectives is to better understand the key physical processes for the onset and evolution of the summer monsoon over Southeast Asia and southern China. Multiple observation platforms (e.g., upper-air soundings, Doppler radar, ships, wind profilers, radiometers, etc.) during SCSMEX provided a first attempt at investigating the detailed characteristics of convection and circulation changes associated with monsoons over the South China Sea region. SCSMEX also provided precipitation derived from atmospheric budgets and comparison to those obtained from the Tropical Rainfall Measuring Mission (TRMM). In this paper, a regional scale <span class="hlt">model</span> (with grid size of 20 km) and Goddard Cumulus Ensemble (GCE) <span class="hlt">model</span> (with 1 km grid size) are used to perform multi-day integration to understand the precipitation processes associated with the summer monsoon over Southeast Asia and southern China. The regional climate <span class="hlt">model</span> is used to understand the soil-precipitation interaction and feedback associated with a flood event that occurred in and around China's Yantz River during SCSMEX Sensitivity tests on various land surface <span class="hlt">models</span>, sea surface temperature (SST) variations, and cloud processes are performed to understand the precipitation processes associated with the onset of the monsoon over the S. China Sea during SCSMEX. These tests have indicated that the land surface <span class="hlt">model</span> has a major impact on the circulation over the S. China Sea. Cloud processes can effect the precipitation pattern while SST variation can effect the precipitation amounts over both land and ocean. The exact location (region) of the flooding can be effected by the soil-rainfall feedback. The GCE-<span class="hlt">model</span> results captured many observed precipitation characteristics because it used a fine grid size. For example, the <span class="hlt">model</span> simulated rainfall temporal variation compared quite well to the sounding-estimated rainfall. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009OcDyn..59...47K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009OcDyn..59...47K"><span id="translatedtitle">Evaluation of Global Ocean Data Assimilation Experiment products on South Florida <span class="hlt">nested</span> simulations with the Hybrid Coordinate 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>Kourafalou, Vassiliki H.; Peng, Ge; Kang, Heesook; Hogan, Patrick J.; Smedstad, Ole-Martin; Weisberg, Robert H.</p> <p>2009-02-01</p> <p>The South Florida Hybrid Coordinate Ocean <span class="hlt">Model</span> (SoFLA-HYCOM) encompasses a variety of coastal regions (the broad Southwest Florida shelf, the narrow Atlantic Keys shelf, the shallow Florida Bay, and Biscayne Bay) and deep regions (the Straits of Florida), including Marine Protected Areas (the Florida Keys Marine Sanctuary and the Dry Tortugas Ecological Reserve). The presence of the strong Loop Current/Florida Current system and associated eddies connects the local and basin-wide dynamics. A multi-<span class="hlt">nested</span> approach has been developed to ensure resolution of coastal-scale processes and proper interaction with the large scale flows. The simulations are free running and effects of data assimilation are introduced through boundary conditions derived from Global Ocean Data Assimilation Experiment products. The study evaluates the effects of boundary conditions on the successful hindcasting of circulation patterns by a <span class="hlt">nested</span> <span class="hlt">model</span>, applied on a dynamically and topographically complex shelf area. Independent (not assimilated) observations are employed for a quantitative validation of the numerical results. The discussion of the prevailing dynamics that are revealed in both <span class="hlt">modeled</span> and observed patterns suggests the importance of topography resolution and local forcing on the inner shelf to middle shelf areas, while large scale processes are found to dominate the outer shelf flows. The results indicate that the successful hindcasting of circulation patterns in a coastal area that is characterized by complex topography and proximity to a large scale current system requires a dynamical downscaling approach, with simulations that are <span class="hlt">nested</span> in a hierarchy of data assimilative outer <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007EnGeo..53..763C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007EnGeo..53..763C"><span id="translatedtitle">A distributed water-heat coupled <span class="hlt">model</span> for mountainous watershed of an inland river basin in Northwest China (III) using the outputs from <span class="hlt">Mesoscale</span> <span class="hlt">model</span> version 5</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Ren-Sheng; Gao, Yan-Hong; Lu, Shi-Hua; Kang, Er-Si; Ji, Xi-Bin; Zhang, Zhi-Hui; Yang, Yong</p> <p>2007-12-01</p> <p>The distributed water-heat coupled (DWHC) <span class="hlt">model</span> is calibrated, with the help of the <span class="hlt">Mesoscale</span> <span class="hlt">model</span> version 5 (MM5), by calculating the daily precipitation, the daily average air temperature at the 2.0 m heights and the daily potential evaporation in Heihe mountainous watershed area and its vicinity (96.786°˜102.284°E, 37.328°˜40.601°N, 17 × 104 km2), from February 11 to June 30, 2003. The MM5 <span class="hlt">model</span> periodically ran every 10 days in 3 km × 3 km grid resolution with an integral time step of 3 s. In the MM5 <span class="hlt">model</span>, many scheme or options are consulted or adopted, such as the Grell scheme cumulus parameterization method, the Dudhia option, the cloud-radiation scheme, MRF PBL option and the modified Oregon State University Land-surface <span class="hlt">model</span> (OSULSM). According to the projection transform methods, the MM5 outputs are interpolated to the 1 km × 1 km grid in Alberts projection by using triangle-based cubic interpolation (Cubic) and nearest neighbor interpolation (Nearest) methods, with which the DWHC <span class="hlt">model</span> shares the same method. The result shows that, when the Nearest method is used, the Nash-Sutcliffe equation value of the daily average runoff is 0.79, the balance error is -0.79% and the goodness of fit R 2 value is 0.81. Meanwhile, when the Cubic method is used, the Nash-Sutcliffe equation value, the balance error and the R 2 value are 0.79, -0.65% and 0.80, respectively. Though the runoff simulation result is not favorable, it is still better than that using measured data at the meteorological and hydrological stations; the latter has a Nash-Sutcliffe equation value of 0.61. The MM5-DWHC <span class="hlt">model</span> results also show that runoff mainly occurs on land surfaces and from shallow soil layers. According to <span class="hlt">model</span> calibration results, certain outputs of MM5 are singular to some extent and the DWHC <span class="hlt">model</span> is very sensitive to the initial values.</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://adsabs.harvard.edu/abs/2014AGUFMGC33E0568F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC33E0568F"><span id="translatedtitle">Application of a <span class="hlt">Mesoscale</span> Atmospheric Coupled Fire <span class="hlt">Model</span> BRAMS-FIRE to Alentejo Woodland Fire and Comparison of Performance with the Fire <span class="hlt">Model</span> WRF-Sfire.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Freitas, S. R.; Menezes, I. C.; Stockler, R.; Mello, R.; Ribeiro, N. A.; Corte-Real, J. A. M.; Surový, P.</p> <p>2014-12-01</p> <p><span class="hlt">Models</span> of fuel with the identification of vegetation patterns of Montado ecosystem in Portugal was incorporated in the <span class="hlt">mesoscale</span> Brazilian Atmospheric <span class="hlt">Modeling</span> System (BRAMS) and coupled with a spread woodland fire <span class="hlt">model</span>. The BRAMS-FIRE is a new system developed by the "Centro de Previsão de Tempo e Estudos Climáticos" (CPTEC/INPE, Brazil) and the "Instituto de Ciências Agrárias e Ambientais Mediterrâneas" (ICAAM, Portugal). The fire <span class="hlt">model</span> used in this effort was originally, developed by Mandel et al. (2013) and further incorporated in the Weather Research and Forecast <span class="hlt">model</span> (WRF). Two grids of high spatial resolution were configured with surface input data and fuel <span class="hlt">models</span> integrated for simulations using both <span class="hlt">models</span> BRAMS-FIRE and WRF-SFIRE. One grid was placed in the plain land near Beja and the other one in the hills of Ossa to evaluate different types of fire propagation and calibrate BRAMS-FIRE. The objective is simulating the effects of atmospheric circulation in local scale, namely the movements of the heat front and energy release associated to it, obtained by this two <span class="hlt">models</span> in an episode of woodland fire which took place in Alentejo area in the last decade, for application to planning and evaluations of agro woodland fire risks. We aim to <span class="hlt">model</span> the behavior of forest fires through a set of equations whose solutions provide quantitative values of one or more variables related to the propagation of fire, described by semi-empirical expressions that are complemented by experimental data allow to obtain the main variables related advancing the perimeter of the fire, as the propagation speed, the intensity of the fire front and fuel consumption and its interaction with atmospheric dynamic system. References Mandel, J., J. D. Beezley, G. Kelman, A. K. Kochanski, V. Y. Kondratenko, B. H. Lynn, and M. Vejmelka, 2013. New features in WRF-SFIRE and the wildfire forecasting and danger system in Israel. Natural Hazards and Earth System Sciences, submitted</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7861M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7861M"><span id="translatedtitle">Application of a <span class="hlt">mesoscale</span> atmospheric coupled fire <span class="hlt">model</span> BRAMS-SFIRE to Alentejo wildland fire and comparison of performance with the fire <span class="hlt">model</span> WRF-SFIRE</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Menezes, Isilda; Freitas, Saulo; Stockler, Rafael; Mello, Rafael; Ribeiro, Nuno; Corte-Real, João; Surový, Peter</p> <p>2015-04-01</p> <p><span class="hlt">Models</span> of fuel with the identification of vegetation patterns of Montado ecosystem in Portugal was incorporated in the <span class="hlt">mesoscale</span> Brazilian Atmospheric <span class="hlt">Modeling</span> System (BRAMS) and coupled with a spread wildland fire <span class="hlt">model</span>. The BRAMS-FIRE is a new system developed by the Centro de Previsão de Tempo e Estudos Climáticos (CPTEC/INPE, Brazil) and the Instituto de Ciências Agrárias e Ambientais Mediterrâneas (ICAAM, Portugal). The fire <span class="hlt">model</span> used in this effort was originally, developed by Mandel et al. (2013) and further incorporated in the Weather Research and Forecast <span class="hlt">model</span> (WRF). Two grids of high spatial resolution were configured with surface input data and fuel <span class="hlt">models</span> integrated for simulations using both <span class="hlt">models</span> BRAMS-SFIRE and WRF-SFIRE. One grid was placed in the plain land and the other one in the hills to evaluate different types of fire propagation and calibrate BRAMS-SFIRE. The objective is simulating the effects of atmospheric circulation in local scale, namely the movements of the heat front and energy release associated to it, obtained by this two <span class="hlt">models</span> in an episode of wildland fire which took place in Alentejo area in the last decade, for application to planning and evaluations of agro wildland fire risks. We aim to <span class="hlt">model</span> the behavior of forest fires through a set of equations whose solutions provide quantitative values of one or more variables related to the propagation of fire, described by semi-empirical expressions that are complemented by experimental data allow to obtain the main variables related advancing the perimeter of the fire, as the propagation speed, the intensity of the fire front and fuel consumption and its interaction with atmospheric dynamic system References Mandel, J., J. D. Beezley, G. Kelman, A. K. Kochanski, V. Y. Kondratenko, B. H. Lynn, and M. Vejmelka, 2013. New features in WRF-SFIRE and the wildfire forecasting and danger system in Israel. Natural Hazards and Earth System Sciences, submitted, Numerical Wildfires, Carg</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMIN12A..04H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMIN12A..04H"><span id="translatedtitle">Utilizing High Performance Computing and Loosely-Coupled <span class="hlt">Nested</span> <span class="hlt">Models</span> to Enable the Computability of Dust Storm Forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Q.; Yang, C.; Benedict, K. K.</p> <p>2011-12-01</p> <p>Both environmental and human challenges, such as natural disasters, require scientifically sound simulations of physical phenomena to better understand the past and to better predict future trends for improved decision support. However, many scientific simulations cannot be processed using a single computer and require computing capability from many distributed computers. The research will explore how to utilize spatiotemporal patterns of phenomena, <span class="hlt">models</span> and computing resources to improve the performance of dust storm forecasting. Additionally, the loosely-coupled <span class="hlt">nesting</span> of two <span class="hlt">models</span> is proposed to support dust storm forecasting for a large area and high resolution to support geospatial decision-making. Within this approach, a dust storm <span class="hlt">model</span> (ETA-8bin) performs a quick forecasting with low spatial resolution (50 km) to identify hotspots with high dust concentration. Afterward, a finer <span class="hlt">model</span> NMM-dust will perform high resolution (3km) forecasting over the hotspot areas in parallel with much smaller size and therefore requiring much less computing power. This research eventually enabled computability of high resolution dust storm forecasting by enabling the interoperable and loosely-coupling <span class="hlt">nested</span> execution of the two <span class="hlt">models</span> ETA-8bin and NMM-dust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1014662','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1014662"><span id="translatedtitle"><span class="hlt">Mesoscale</span> hybrid calibration artifact</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.</p> <p>2010-09-07</p> <p>A <span class="hlt">mesoscale</span> calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23325041','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23325041"><span id="translatedtitle">Predicting spatial patterns of eagle migration using a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span>: a case study associated with a mountain-ridge wind development.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ainslie, B; Alexander, N; Johnston, N; Bradley, J; Pomeroy, A C; Jackson, P L; Otter, K A</p> <p>2014-01-01</p> <p>High resolution numerical atmospheric <span class="hlt">modeling</span> around a mountain ridge in Northeastern British Columbia (BC), Canada was performed in order to examine the influence of meteorology and topography on Golden Eagle migration pathways at the <span class="hlt">meso-scale</span> (tens of km). During three eagle fall migration periods (2007-2009), local meteorological conditions on the day of peak bird counts were <span class="hlt">modeled</span> using the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. Hourly local surface wind speed, wind direction, temperature, pressure and relative humidity were also monitored during these migration periods. Eagle migration flight paths were observed from the ground and converted to three-dimensional tracks using ArcGIS. The observed eagle migration flight paths were compared with the <span class="hlt">modeled</span> vertical velocity wind fields. Flight tracks across the study area were also simulated using the <span class="hlt">modeled</span> vertical velocity field in a migration <span class="hlt">model</span> based on a fluid-flow analogy. It was found that both the large-scale weather conditions and the horizontal wind fields across the study area were broadly similar on each of the <span class="hlt">modeled</span> migration days. Nonetheless, the location and density of flight tracks across the domain varied between days, with the 2007 event producing more tracks to the southwest of the observation location than the other 2 days. The <span class="hlt">modeled</span> wind fields suggest that it is not possible for the eagles to traverse the study area without leaving updraft regions, but birds do converge on the locations of updrafts as they move through the area. Statistical associations between observed eagles positions and the vertical velocity field suggest that to the northwest (and to a lesser extent the southwest) of the main study ridge (Johnson col), eagles can always find updrafts but that they must pass through downdraft regions in the NE and SE as they make their way across the study area. Finally, the simulated flight tracks based on the fluid-flow <span class="hlt">model</span> and the vertical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014IJBm...58...17A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014IJBm...58...17A"><span id="translatedtitle">Predicting spatial patterns of eagle migration using a <span class="hlt">mesoscale</span> atmospheric <span class="hlt">model</span>: a case study associated with a mountain-ridge wind development</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ainslie, B.; Alexander, N.; Johnston, N.; Bradley, J.; Pomeroy, A. C.; Jackson, P. L.; Otter, K. A.</p> <p>2014-01-01</p> <p>High resolution numerical atmospheric <span class="hlt">modeling</span> around a mountain ridge in Northeastern British Columbia (BC), Canada was performed in order to examine the influence of meteorology and topography on Golden Eagle migration pathways at the <span class="hlt">meso-scale</span> (tens of km). During three eagle fall migration periods (2007-2009), local meteorological conditions on the day of peak bird counts were <span class="hlt">modeled</span> using the Regional Atmospheric <span class="hlt">Modeling</span> System (RAMS) <span class="hlt">mesoscale</span> <span class="hlt">model</span>. Hourly local surface wind speed, wind direction, temperature, pressure and relative humidity were also monitored during these migration periods. Eagle migration flight paths were observed from the ground and converted to three-dimensional tracks using ArcGIS. The observed eagle migration flight paths were compared with the <span class="hlt">modeled</span> vertical velocity wind fields. Flight tracks across the study area were also simulated using the <span class="hlt">modeled</span> vertical velocity field in a migration <span class="hlt">model</span> based on a fluid-flow analogy. It was found that both the large-scale weather conditions and the horizontal wind fields across the study area were broadly similar on each of the <span class="hlt">modeled</span> migration days. Nonetheless, the location and density of flight tracks across the domain varied between days, with the 2007 event producing more tracks to the southwest of the observation location than the other 2 days. The <span class="hlt">modeled</span> wind fields suggest that it is not possible for the eagles to traverse the study area without leaving updraft regions, but birds do converge on the locations of updrafts as they move through the area. Statistical associations between observed eagles positions and the vertical velocity field suggest that to the northwest (and to a lesser extent the southwest) of the main study ridge (Johnson col), eagles can always find updrafts but that they must pass through downdraft regions in the NE and SE as they make their way across the study area. Finally, the simulated flight tracks based on the fluid-flow <span class="hlt">model</span> and the vertical</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6237S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6237S"><span id="translatedtitle">Distributed nitrate transport and reaction routines (NTR) inside the <span class="hlt">mesoscale</span> Hydrological <span class="hlt">Model</span> (mHM) framework: Development and Application in the Selke catchment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sinha, Sumit; Rode, Michael; Kumar, Rohini; Yang, Xiaoqiang; Samaniego, Luis; Borchardt, Dietrich</p> <p>2016-04-01</p> <p>Precise measurements of where, when and how much denitrification occurs on the basis of measurements alone persist to be vexing and intractable research problem at all spatial and temporal scales. As a result, <span class="hlt">models</span> have become essential and vital tools for furthering our current understanding of the processes that control denitrification on catchment scale. Emplacement of Water Framework Directive (WFD) and continued efforts in improving water treatment facilities