Emergent Behavior of Arctic Precipitation in Response to Enhanced Arctic Warming

NASA Astrophysics Data System (ADS)

Anderson, Bruce T.; Feldl, Nicole; Lintner, Benjamin R.

2018-03-01

Amplified warming of the high latitudes in response to human-induced emissions of greenhouse gases has already been observed in the historical record and is a robust feature evident across a hierarchy of model systems, including the models of the Coupled Model Intercomparison Project Phase 5 (CMIP5). The main aims of this analysis are to quantify intermodel differences in the Arctic amplification (AA) of the global warming signal in CMIP5 RCP8.5 (Representative Concentration Pathway 8.5) simulations and to diagnose these differences in the context of the energy and water cycles of the region. This diagnosis reveals an emergent behavior between the energetic and hydrometeorological responses of the Arctic to warming: in particular, enhanced AA and its associated reduction in dry static energy convergence is balanced to first order by latent heating via enhanced precipitation. This balance necessitates increasing Arctic precipitation with increasing AA while at the same time constraining the magnitude of that precipitation increase. The sensitivity of the increase, 1.25 (W/m2)/K ( 240 (km3/yr)/K), is evident across a broad range of historical and projected AA values. Accounting for the energetic constraint on Arctic precipitation, as a function of AA, in turn informs understanding of both the sign and magnitude of hydrologic cycle changes that the Arctic may experience.

The 1997 North American Interagency Intercomparison of Ultraviolet Spectroradiometers Including Narrowband Filter Radiometers

PubMed Central

Lantz, Kathleen; Disterhoft, Patrick; Early, Edward; Thompson, Ambler; DeLuisi, John; Berndt, Jerry; Harrison, Lee; Kiedron, Peter; Ehramjian, James; Bernhard, Germar; Cabasug, Lauriana; Robertson, James; Mou, Wanfeng; Taylor, Thomas; Slusser, James; Bigelow, David; Durham, Bill; Janson, George; Hayes, Douglass; Beaubien, Mark; Beaubien, Arthur

2002-01-01

The fourth North American Intercomparison of Ultraviolet Monitoring Spectroradiometers was held September 15 to 25, 1997 at Table Mountain outside of Boulder, Colorado, USA. Concern over stratospheric ozone depletion has prompted several government agencies in North America to establish networks of spectroradiometers for monitoring solar ultraviolet irradiance at the surface of the Earth. The main purpose of the Intercomparison was to assess the ability of spectroradiometers to accurately measure solar ultraviolet irradiance, and to compare the results between instruments of different monitoring networks. This Intercomparison was coordinated by NIST and NOAA, and included participants from the ASRC, EPA, NIST, NSF, SERC, USDA, and YES. The UV measuring instruments included scanning spectroradiometers, spectrographs, narrow band multi-filter radiometers, and broadband radiometers. Instruments were characterized for wavelength accuracy, bandwidth, stray-light rejection, and spectral irradiance responsivity. The spectral irradiance responsivity was determined two to three times outdoors to assess temporal stability. Synchronized spectral scans of the solar irradiance were performed over several days. Using the spectral irradiance responsivities determined with the NIST traceable standard lamp, and a simple convolution technique with a Gaussian slit-scattering function to account for the different bandwidths of the instruments, the measured solar irradiance from the spectroradiometers excluding the filter radiometers at 16.5 h UTC had a relative standard deviation of ±4 % for wavelengths greater than 305 nm. The relative standard deviation for the solar irradiance at 16.5 h UTC including the filter radiometer was ±4 % for filter functions above 300 nm. PMID:27446717

AN INTERLABORATORY COMPARISON ON THE DETERMINATION OF 241Am, 244Cm AND 252Cf IN URINE.

PubMed

Gerstmann, Udo C; Taubner, Kerstin; Hartmann, Martina

2016-09-01

An intercomparison exercise on the determination of (241)Am, (244)Cm and (252)Cf in urine was performed. Since it was designed with regard to emergency preparedness, the detection limit for each nuclide was set to 0.1 Bq per 24-h urine sample. Most of the participating laboratories were established bioassay laboratories. However, some laboratories that routinely determine (241)Am only in environmental samples were also invited in order to explore their potential for emergency bioassay analysis. Another aspect of the intercomparison was to investigate the performance of all laboratories concerning the chemical yields of the (243)Am tracer in comparison with (244)Cm and (252)Cf. In summary, both types of laboratories showed good results. There was a negative bias for the results of (244)Cm and (252)Cf, which can be explained by slightly different radiochemical behaviours of americium, curium and californium and which is in agreement with results reported in the literature. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

1993 Intercomparison of Photometric Units Maintained at NIST (USA) and PTB (Germany)

PubMed Central

Ohno, Yoshihiro; Sauter, Georg

1995-01-01

A bilateral intercomparison of photometric units between NIST, USA and PTB, Germany has been conducted to update the knowledge of the relationship between the photometric units disseminated in each country. The luminous intensity unit (cd) and the luminous flux unit (lm) maintained at both laboratories are compared by circulating transfer standard lamps. Also, the photometric responsivity sv is compared by circulating a V(λ)-corrected detector with a built-in current-to-voltage converter. The results show that the difference of luminous intensity unit between NIST and PTB, (PTB-NIST)/NIST, is 0.2 % with a relative expanded uncertainty (coverage factor k = 2) of 0.24 %. The difference is reduced significantly from that at the 1985 CCPR intercomparison (0.9 %). The difference in luminous flux unit, (PTB – NIST)/NIST, is found to be 1.5 % with a relative expanded uncertainty (coverage factor k =2) of 0.15 %. The difference remained nearly the same as that at the 1985 intercomparison (1.6 %). These results agree with what is predicted from the history of maintaining the units at each laboratory. PMID:29151737

The 1995 North American Interagency Intercomparison of Ultraviolet Monitoring Spectroradiometers

PubMed Central

Early, Edward; Thompson, Ambler; Johnson, Carol; DeLuisi, John; Disterhoft, Patrick; Wardle, David; Wu, Edmund; Mou, Wanfeng; Sun, Yongchen; Lucas, Timothy; Mestechkina, Tanya; Harrison, Lee; Berndt, Jerry; Hayes, Douglas S.

1998-01-01

Concern over stratospheric ozone depletion has prompted several government agencies in North America to establish networks of spectroradiometers for monitoring solar ultraviolet irradiance at the surface of the Earth. To assess the ability of spectroradiometers to accurately measure solar ultraviolet irradiance, and to compare the results between instruments of different monitoring networks, the second North American Intercomparison of Ultraviolet Monitoring Spectroradiometers was held June 12 to 23, 1995 at Table Mountain outside Boulder, Colorado, USA. This Intercomparison was coordinated by the National Institute of Standards and Technology (NIST) and the National Oceanic and Atmospheric Administration (NOAA). Participating agencies were the Environmental Protection Agency; the National Science Foundation; the Smithsonian Environmental Research Center; the Department of Agriculture; and the Atmospheric Environment Service, Canada. Instruments were characterized for wavelength uncertainty, bandwidth, stray-light rejection, and spectral irradiance responsivity, the latter with a NIST standard lamp operating in a specially designed field calibration unit. The spectral irradiance responsivity, determined once indoors and twice outdoors, demonstrated that while the responsivities changed upon moving the instruments, they were relatively stable when the instruments remained outdoors. Synchronized spectral scans of the solar irradiance were performed over several days. Using the spectral irradiance responsivities determined with the NIST standard lamp and three different convolution functions to account for the different bandwidths of the instruments, the measured solar irradiances generally agreed to within 3 %. PMID:28009371

The Agricultural Model Intercomparison and Improvement Project (AgMIP): Progress and Preliminary Results

NASA Astrophysics Data System (ADS)

Rosenzweig, C.

2011-12-01

The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a distributed climate-scenario simulation exercise for historical model intercomparison and future climate change conditions with participation of multiple crop and agricultural trade modeling groups around the world. The goals of AgMIP are to improve substantially the characterization of risk of hunger and world food security due to climate change and to enhance adaptation capacity in both developing and developed countries. Recent progress and the current status of AgMIP will be presented, highlighting three areas of activity: preliminary results from crop pilot studies, outcomes from regional workshops, and emerging scientific challenges. AgMIP crop modeling efforts are being led by pilot studies, which have been established for wheat, maize, rice, and sugarcane. These crop-specific initiatives have proven instrumental in testing and contributing to AgMIP protocols, as well as creating preliminary results for aggregation and input to agricultural trade models. Regional workshops are being held to encourage collaborations and set research activities in motion for key agricultural areas. The first of these workshops was hosted by Embrapa and UNICAMP and held in Campinas, Brazil. Outcomes from this meeting have informed crop modeling research activities within South America, AgMIP protocols, and future regional workshops. Several scientific challenges have emerged and are currently being addressed by AgMIP researchers. Areas of particular interest include geospatial weather generation, ensemble methods for climate scenarios and crop models, spatial aggregation of field-scale yields to regional and global production, and characterization of future changes in climate variability.

The Second SIMBIOS Radiometric Intercomparison (SIMRIC-2), March-November 2002. Volume 2

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Abel, Peter; Carder, Kendall; Chapin, Albert; Clark, Dennis; Cooper, John; Davis, Curtis; English, David; Fargion, Giulietta; Feinholz, Michael;

Visible light nitrogen dioxide spectrophotometer intercomparison: Mount Kobau, British Columbia, July 28 to August 10, 1991

NASA Technical Reports Server (NTRS)

Mcelroy, C. T.; Elokhov, A. S.; Elansky, N.; Frank, H.; Johnston, P.; Kerr, J. B.

1994-01-01

Under the auspices of the World Meteorological Organization, Environment Canada hosted an international comparison of visible light spectrophotometers at Mt. Kobau, British Columbia in August of 1991. Instruments from four countries were involved. The intercomparison results have indicated that some significant differences exist in the responses of the various instruments, and have provided a basis for the comparison of the historical data sets which currently exist as a result of the independent researches carried out in the past in the former Soviet Union, New Zealand, and Canada.

Intercomparison and interpretation of climate feedback processes in 19 atmospheric general circulation models

NASA Technical Reports Server (NTRS)

Cess, R. D.; Potter, G. L.; Blanchet, J. P.; Boer, G. J.; Del Genio, A. D.

1990-01-01

The present study provides an intercomparison and interpretation of climate feedback processes in 19 atmospheric general circulation models. This intercomparison uses sea surface temperature change as a surrogate for climate change. The interpretation of cloud-climate interactions is given special attention. A roughly threefold variation in one measure of global climate sensitivity is found among the 19 models. The important conclusion is that most of this variation is attributable to differences in the models' depiction of cloud feedback, a result that emphasizes the need for improvements in the treatment of clouds in these models if they are ultimately to be used as reliable climate predictors. It is further emphazied that cloud feedback is the consequence of all interacting physical and dynamical processes in a general circulation model. The result of these processes is to produce changes in temperature, moisture distribution, and clouds which are integrated into the radiative response termed cloud feedback.

The Pliocene Model Intercomparison Project - Phase 2

NASA Astrophysics Data System (ADS)

Haywood, Alan; Dowsett, Harry; Dolan, Aisling; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark; Hunter, Stephen; Lunt, Daniel; Pound, Matthew; Salzmann, Ulrich

2016-04-01

The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, and their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate, and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilised for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilise state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land/ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.

A potato model intercomparison across varying climates and productivity levels

USDA-ARS?s Scientific Manuscript database

A potato crop multi-model assessment was conducted to quantify variation among models and evaluate responses to climate change. Nine modeling groups simulated agronomic and climatic responses at low- (Chinoli, Bolivia and Gisozi, Burundi) and high- (Jyndevad, Denmark and Washington, United States) ...

Dose evaluation in criticality accidents using response of Panasonic TL personal dosemeters (UD-809/UD-802).

PubMed

Zeyrek, C T; Gündüz, H

2012-09-01

This study gives the results of dosimetry measurements carried out in the Silène reactor at Valduc (France) with neutron and photon personal thermoluminescence dosemeters (TLDs) in mixed neutron and gamma radiation fields, in the frame of the international accident dosimetry intercomparison programme in 2002. The intercomparison consisted of a series of three irradiation scenarios. The scenarios took place at the Valduc site (France) by using the Silène experimental reactor. For neutron and photon dosimetry, Panasonic model UD-809 and UD-802 personal TLDs were used together.

Low-cost solar array project: Four absolute cavity radiometer (pyrheliometer) intercomparisons at New River, Arizona: Radiometer standards

NASA Technical Reports Server (NTRS)

Estey, R. S.; Seaman, C. H.

1981-01-01

Four detailed intercomparisons were made for a number of models of cavity-type self-calibrating radiometers (pyrheliometers). Each intercomparison consisted of simultaneous readings of pyrheliometers at 30-second intervals in runs of 10 minutes, with at least 15 runs per intercomparison. Twenty-seven instruments were in at least one intercomparison, and five were in all four. Summarized results and all raw data are provided from the intercomparisons.

Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauer, Susanne

2015-02-09

We participated in a FASTER SCM intercomparison for which we ran our SCM for 3 years at the SGP to analyze statistics of the precipitation field (Song et al., 2013). An important feature of these simulations was the use of relaxation forcing to observed T, q, which decouples the model convection from the forcing and allows precipitation errors to emerge. Because the GISS cumulus parameterization includes a trigger that prevents convection until sufficient lifting is present, and because convection at the SGP is usually triggered by mesoscale motions that are not represented in the forcing when relaxation is applied, themore » duration of SCM precipitation is shorter than observed (Del Genio and Wolf, 2012) and thus its mean precipitation less than observed. However, its diurnal cycle phase is correct, and it is the only operational cumulus parameterization in the intercomparison that does not produce excessive warm season precipitation under weak large-scale forcing conditions.« less

Solar irradiance reduction to counteract radiative forcing from a quadrupling of CO2: climate responses simulated by four earth system models

NASA Astrophysics Data System (ADS)

Schmidt, H.; Alterskjær, K.; Karam, D. Bou; Boucher, O.; Jones, A.; Kristjánsson, J. E.; Niemeier, U.; Schulz, M.; Aaheim, A.; Benduhn, F.; Lawrence, M.; Timmreck, C.

2012-06-01

In this study we compare the response of four state-of-the-art Earth system models to climate engineering under scenario G1 of two model intercomparison projects: GeoMIP (Geoengineering Model Intercomparison Project) and IMPLICC (EU project "Implications and risks of engineering solar radiation to limit climate change"). In G1, the radiative forcing from an instantaneous quadrupling of the CO2 concentration, starting from the preindustrial level, is balanced by a reduction of the solar constant. Model responses to the two counteracting forcings in G1 are compared to the preindustrial climate in terms of global means and regional patterns and their robustness. While the global mean surface air temperature in G1 remains almost unchanged compared to the control simulation, the meridional temperature gradient is reduced in all models. Another robust response is the global reduction of precipitation with strong effects in particular over North and South America and northern Eurasia. In comparison to the climate response to a quadrupling of CO2 alone, the temperature responses are small in experiment G1. Precipitation responses are, however, in many regions of comparable magnitude but globally of opposite sign.

Transient regional climate change: analysis of the summer climate response in a high-resolution, century-scale, ensemble experiment over the continental United States

PubMed Central

Diffenbaugh, Noah S.; Ashfaq, Moetasim; Scherer, Martin

2013-01-01

Integrating the potential for climate change impacts into policy and planning decisions requires quantification of the emergence of sub-regional climate changes that could occur in response to transient changes in global radiative forcing. Here we report results from a high-resolution, century-scale, ensemble simulation of climate in the United States, forced by atmospheric constituent concentrations from the Special Report on Emissions Scenarios (SRES) A1B scenario. We find that 21st century summer warming permanently emerges beyond the baseline decadal-scale variability prior to 2020 over most areas of the continental U.S. Permanent emergence beyond the baseline annual-scale variability shows much greater spatial heterogeneity, with emergence occurring prior to 2030 over areas of the southwestern U.S., but not prior to the end of the 21st century over much of the southcentral and southeastern U.S. The pattern of emergence of robust summer warming contrasts with the pattern of summer warming magnitude, which is greatest over the central U.S. and smallest over the western U.S. In addition to stronger warming, the central U.S. also exhibits stronger coupling of changes in surface air temperature, precipitation, and moisture and energy fluxes, along with changes in atmospheric circulation towards increased anticylonic anomalies in the mid-troposphere and a poleward shift in the mid-latitude jet aloft. However, as a fraction of the baseline variability, the transient warming over the central U.S. is smaller than the warming over the southwestern or northeastern U.S., delaying the emergence of the warming signal over the central U.S. Our comparisons with observations and the Coupled Model Intercomparison Project Phase 3 (CMIP3) ensemble of global climate model experiments suggest that near-term global warming is likely to cause robust sub-regional-scale warming over areas that exhibit relatively little baseline variability. In contrast, where there is greater variability in the baseline climate dynamics, there can be greater variability in the response to elevated greenhouse forcing, decreasing the robustness of the transient warming signal. PMID:24307747

Global Intercomparison of 12 Land Surface Heat Flux Estimates

NASA Technical Reports Server (NTRS)

Jimenez, C.; Prigent, C.; Mueller, B.; Seneviratne, S. I.; McCabe, M. F.; Wood, E. F.; Rossow, W. B.; Balsamo, G.; Betts, A. K.; Dirmeyer, P. A.;

WCRP Task Team for the Intercomparison of Reanalyses (TIRA): Motivation and Progress

NASA Technical Reports Server (NTRS)

Bosilovich, Michael

2017-01-01

Reanalyses have proven to be an important resource for weather and climate related research, as well as societal applications at large. Several centers have emerged to produce new atmospheric reanalyses in various forms every few years. In addition, land and ocean communities are producing disciplinary uncoupled reanalyses. Current research and development in reanalysis is directed at (1) extending the length of reanalyzed period and (2) use of coupled Earth system models for climate reanalysis. While WCRPs involvement in the reanalyses communities through its Data Advisory Council (WDAC) has been substantial, for example in organizing international conferences on reanalyses, a central team of reanalyses expertise is not in place in the WCRP structure. The differences among reanalyses and their inherent uncertainties are some of the most important questions for both users and developers of reanalyses. Therefore, a collaborative effort to systematically assess and intercompare reanalyses would be a logical progression that fills the needs of the community and contributes to the WCRP mission. The primary charge to the TIRA is to develop a reanalysis intercomparison project plan that will attain the following objectives.1)To foster understanding and estimation of uncertainties in reanalysis data by intercomparison and other means 2)To communicate new developments and best practices among the reanalyses producing centers 3)To enhance the understanding of data and assimilation issues and their impact on uncertainties, leading to improved reanalyses for climate assessment 4)To communicate the strengths and weaknesses of reanalyses, their fitness for purpose, and best practices in the use of reanalysis datasets by the scientific community. This presentation outlines the need for a task team on reanalyses, their intercomparison, the objectives of the team and progress thus far.

Robust increases in severe thunderstorm environments in response to greenhouse forcing

PubMed Central

Diffenbaugh, Noah S.; Scherer, Martin; Trapp, Robert J.

2013-01-01

Although severe thunderstorms are one of the primary causes of catastrophic loss in the United States, their response to elevated greenhouse forcing has remained a prominent source of uncertainty for climate change impacts assessment. We find that the Coupled Model Intercomparison Project, Phase 5, global climate model ensemble indicates robust increases in the occurrence of severe thunderstorm environments over the eastern United States in response to further global warming. For spring and autumn, these robust increases emerge before mean global warming of 2 °C above the preindustrial baseline. We also find that days with high convective available potential energy (CAPE) and strong low-level wind shear increase in occurrence, suggesting an increasing likelihood of atmospheric conditions that contribute to the most severe events, including tornadoes. In contrast, whereas expected decreases in mean wind shear have been used to argue for a negative influence of global warming on severe thunderstorms, we find that decreases in shear are in fact concentrated in days with low CAPE and therefore do not decrease the total occurrence of severe environments. Further, we find that the shift toward high CAPE is most concentrated in days with low convective inhibition, increasing the occurrence of high-CAPE/low-convective inhibition days. The fact that the projected increases in severe environments are robust across a suite of climate models, emerge in response to relatively moderate global warming, and result from robust physical changes suggests that continued increases in greenhouse forcing are likely to increase severe thunderstorm occurrence, thereby increasing the risk of thunderstorm-related damage. PMID:24062439

Robust increases in severe thunderstorm environments in response to greenhouse forcing.

PubMed

Diffenbaugh, Noah S; Scherer, Martin; Trapp, Robert J

2013-10-08

Although severe thunderstorms are one of the primary causes of catastrophic loss in the United States, their response to elevated greenhouse forcing has remained a prominent source of uncertainty for climate change impacts assessment. We find that the Coupled Model Intercomparison Project, Phase 5, global climate model ensemble indicates robust increases in the occurrence of severe thunderstorm environments over the eastern United States in response to further global warming. For spring and autumn, these robust increases emerge before mean global warming of 2 °C above the preindustrial baseline. We also find that days with high convective available potential energy (CAPE) and strong low-level wind shear increase in occurrence, suggesting an increasing likelihood of atmospheric conditions that contribute to the most severe events, including tornadoes. In contrast, whereas expected decreases in mean wind shear have been used to argue for a negative influence of global warming on severe thunderstorms, we find that decreases in shear are in fact concentrated in days with low CAPE and therefore do not decrease the total occurrence of severe environments. Further, we find that the shift toward high CAPE is most concentrated in days with low convective inhibition, increasing the occurrence of high-CAPE/low-convective inhibition days. The fact that the projected increases in severe environments are robust across a suite of climate models, emerge in response to relatively moderate global warming, and result from robust physical changes suggests that continued increases in greenhouse forcing are likely to increase severe thunderstorm occurrence, thereby increasing the risk of thunderstorm-related damage.

Ozone Response to Aircraft Emissions: Sensitivity Studies with Two-dimensional Models

NASA Technical Reports Server (NTRS)

Ko, Malcolm K. W.; Weisenstein, Debra; Jackman, Charles H.; Douglass, Anne R.; Bureske, K.; Weubbles, Donald J.; Kinnison, Douglas E.; Brasseur, G.; Pyle, J.; Jones, Anna

1992-01-01

Our first intercomparison/assessment of the effects of a proposed high-speed civil transport (HSCT) fleet on the stratosphere is presented. These model calculations should be considered more as sensitivity studies, primarily designed to serve the following purposes: (1) to allow for intercomparison of model predictions; (2) to focus on the range of fleet operations and engine specifications giving minimal environmental impact; and (3) to provide the basis for future assessment studies. The basic scenarios were chosen to be as realistic as possible, using the information available on anticipated developments in technology. They are not to be interpreted as a commitment or goal for environmental acceptability.

Design of the MISMIP+, ISOMIP+, and MISOMIP ice-sheet, ocean, and coupled ice sheet-ocean intercomparison projects

NASA Astrophysics Data System (ADS)

Asay-Davis, Xylar; Cornford, Stephen; Martin, Daniel; Gudmundsson, Hilmar; Holland, David; Holland, Denise

2015-04-01

The MISMIP and MISMIP3D marine ice sheet model intercomparison exercises have become popular benchmarks, and several modeling groups have used them to show how their models compare to both analytical results and other models. Similarly, the ISOMIP (Ice Shelf-Ocean Model Intercomparison Project) experiments have acted as a proving ground for ocean models with sub-ice-shelf cavities.As coupled ice sheet-ocean models become available, an updated set of benchmark experiments is needed. To this end, we propose sequel experiments, MISMIP+ and ISOMIP+, with an end goal of coupling the two in a third intercomparison exercise, MISOMIP (the Marine Ice Sheet-Ocean Model Intercomparison Project). Like MISMIP3D, the MISMIP+ experiments take place in an idealized, three-dimensional setting and compare full 3D (Stokes) and reduced, hydrostatic models. Unlike the earlier exercises, the primary focus will be the response of models to sub-shelf melting. The chosen configuration features an ice shelf that experiences substantial lateral shear and buttresses the upstream ice, and so is well suited to melting experiments. Differences between the steady states of each model are minor compared to the response to melt-rate perturbations, reflecting typical real-world applications where parameters are chosen so that the initial states of all models tend to match observations. The three ISOMIP+ experiments have been designed to to make use of the same bedrock topography as MISMIP+ and using ice-shelf geometries from MISMIP+ results produced by the BISICLES ice-sheet model. The first two experiments use static ice-shelf geometries to simulate the evolution of ocean dynamics and resulting melt rates to a quasi-steady state when far-field forcing changes in either from cold to warm or from warm to cold states. The third experiment prescribes 200 years of dynamic ice-shelf geometry (with both retreating and advancing ice) based on a BISICLES simulation along with similar flips between warm and cold states in the far-field ocean forcing. The MISOMIP experiment combines the MISMIP+ experiments with the third ISOMIP+ experiment. Changes in far-field ocean forcing lead to a rapid (over ~1-2 years) increase in sub-ice-shelf melting, which is allowed to drive ice-shelf retreat for ~100 years. Then, the far-field forcing is switched to a cold state, leading to a rapid decrease in melting and a subsequent advance over ~100 years. To illustrate, we present results from BISICLES and POP2x experiments for each of the three intercomparison exercises.

Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, A.; Andreas, A.; Ottoson, L.

2014-05-01

This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

The Radiative Forcing Model Intercomparison Project (RFMIP): Assessment and characterization of forcing to enable feedback studies

NASA Astrophysics Data System (ADS)

Pincus, R.; Stevens, B. B.; Forster, P.; Collins, W.; Ramaswamy, V.

2014-12-01

The Radiative Forcing Model Intercomparison Project (RFMIP): Assessment and characterization of forcing to enable feedback studies An enormous amount of attention has been paid to the diversity of responses in the CMIP and other multi-model ensembles. This diversity is normally interpreted as a distribution in climate sensitivity driven by some distribution of feedback mechanisms. Identification of these feedbacks relies on precise identification of the forcing to which each model is subject, including distinguishing true error from model diversity. The Radiative Forcing Model Intercomparison Project (RFMIP) aims to disentangle the role of forcing from model sensitivity as determinants of varying climate model response by carefully characterizing the radiative forcing to which such models are subject and by coordinating experiments in which it is specified. RFMIP consists of four activities: 1) An assessment of accuracy in flux and forcing calculations for greenhouse gases under past, present, and future climates, using off-line radiative transfer calculations in specified atmospheres with climate model parameterizations and reference models 2) Characterization and assessment of model-specific historical forcing by anthropogenic aerosols, based on coordinated diagnostic output from climate models and off-line radiative transfer calculations with reference models 3) Characterization of model-specific effective radiative forcing, including contributions of model climatology and rapid adjustments, using coordinated climate model integrations and off-line radiative transfer calculations with a single fast model 4) Assessment of climate model response to precisely-characterized radiative forcing over the historical record, including efforts to infer true historical forcing from patterns of response, by direct specification of non-greenhouse-gas forcing in a series of coordinated climate model integrations This talk discusses the rationale for RFMIP, provides an overview of the four activities, and presents preliminary motivating results.

Trilateral Intercomparison of Photometric Units Maintained at NIST (USA), NPL (UK), and PTB (Germany)

PubMed Central

Ohno, Yoshi; Goodman, Teresa; Sauter, Georg

1999-01-01

A trilateral intercomparison of photometric units between NIST (USA), NPL (UK), and PTB (Germany) has been conducted to update the knowledge of the relationship between the photometric units disseminated in the three countries. The luminous intensity unit (cd), the luminous responsivity scale (A/lx), and the luminous flux unit (lm) maintained at each laboratory were compared by circulating transfer standard lamps and photometers. The results showed that the relative luminous intensity values, with respect to the average, measured by NIST, NPL, and PTB were 1.0014, 1.0021, and 0.9966; the relative inverse values of the luminous responsivity (corresponding to illuminance) were 1.0023, 1.0011, and 0.9965; the relative luminous flux values were 0.9994, 1.0034, and 0.9972, respectively. The results agreed within the stated uncertainties of the units maintained at the three laboratories.

Agricultural model intercomparison and improvement project: Overview of model intercomparisons

USDA-ARS?s Scientific Manuscript database

Improvement of crop simulation models to better estimate growth and yield is one of the objectives of the Agricultural Model Intercomparison and Improvement Project (AgMIP). The overall goal of AgMIP is to provide an assessment of crop model through rigorous intercomparisons and evaluate future clim...

The Pliocene Model Intercomparison Project (PlioMIP) Phase 2: scientific objectives and experimental design

NASA Astrophysics Data System (ADS)

Haywood, Alan M.; Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark A.; Hunter, Stephen J.; Lunt, Daniel J.; Pound, Matthew; Salzmann, Ulrich

2016-03-01

The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, as well as their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilized for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilize state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land-ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales, and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.

The Pliocene Model Intercomparison Project (PlioMIP) Phase 2: Scientific Objectives and Experimental Design

NASA Technical Reports Server (NTRS)

Haywood, Alan M.; Dowsett, Harry J.; Dolan, Aisling M.; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark A.; Hunter, Stephen J.; Lunt, Daniel J.; Pound, Matthew;

CGILS Phase 2 LES intercomparison of response of subtropical marine low cloud regimes to CO 2 quadrupling and a CMIP3 composite forcing change: Large eddy simulation of cloud feedbacks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blossey, Peter N.; Bretherton, Christopher S.; Cheng, Anning

We extended Phase 1 of the CGILS large-eddy simulation (LES) intercomparison in order to understand if subtropical marine boundary-layer clouds respond to idealized climate perturbations consistently in six LES models. Here the responses to quadrupled carbon dioxide (“fast adjustment”) and to a composite climate perturbation representative of CMIP3 multimodel mean 2×CO 2 near-equilibrium conditions are analyzed. As in Phase 1, the LES is run to equilibrium using specified steady summertime forcings representative of three locations in the Northeast Pacific Ocean in shallow well-mixed stratocumulus, decoupled stratocumulus, and shallow cumulus cloud regimes. Our results are generally consistent with a single-LES studymore » of Bretherton et al. (2013) on which this intercomparison was based. Both quadrupled CO 2 and the composite climate perturbation result in less cloud and a shallower boundary layer for all models in well-mixed stratocumulus and for all but a single LES in decoupled stratocumulus and shallow cumulus, corroborating similar findings from global climate models (GCMs). For both perturbations, the amount of cloud reduction varies across the models, but there is less intermodel scatter than in GCMs. Furthermore, the cloud radiative effect changes are much larger in the stratocumulus-capped regimes than in the shallow cumulus regime, for which precipitation buffering may damp the cloud response. In the decoupled stratocumulus and cumulus regimes, both the CO 2 increase and CMIP3 perturbations reduce boundary-layer decoupling, due to the shallowing of inversion height.« less

CGILS Phase 2 LES intercomparison of response of subtropical marine low cloud regimes to CO 2 quadrupling and a CMIP3 composite forcing change: Large eddy simulation of cloud feedbacks

DOE PAGES

Blossey, Peter N.; Bretherton, Christopher S.; Cheng, Anning; ...

2016-10-27

We extended Phase 1 of the CGILS large-eddy simulation (LES) intercomparison in order to understand if subtropical marine boundary-layer clouds respond to idealized climate perturbations consistently in six LES models. Here the responses to quadrupled carbon dioxide (“fast adjustment”) and to a composite climate perturbation representative of CMIP3 multimodel mean 2×CO 2 near-equilibrium conditions are analyzed. As in Phase 1, the LES is run to equilibrium using specified steady summertime forcings representative of three locations in the Northeast Pacific Ocean in shallow well-mixed stratocumulus, decoupled stratocumulus, and shallow cumulus cloud regimes. Our results are generally consistent with a single-LES studymore » of Bretherton et al. (2013) on which this intercomparison was based. Both quadrupled CO 2 and the composite climate perturbation result in less cloud and a shallower boundary layer for all models in well-mixed stratocumulus and for all but a single LES in decoupled stratocumulus and shallow cumulus, corroborating similar findings from global climate models (GCMs). For both perturbations, the amount of cloud reduction varies across the models, but there is less intermodel scatter than in GCMs. Furthermore, the cloud radiative effect changes are much larger in the stratocumulus-capped regimes than in the shallow cumulus regime, for which precipitation buffering may damp the cloud response. In the decoupled stratocumulus and cumulus regimes, both the CO 2 increase and CMIP3 perturbations reduce boundary-layer decoupling, due to the shallowing of inversion height.« less

Results of the Greenland ice sheet model initialisation experiments: ISMIP6 - initMIP-Greenland

NASA Astrophysics Data System (ADS)

Goelzer, Heiko; Nowicki, Sophie; Edwards, Tamsin; Beckley, Matthew

2017-04-01

Ice sheet model initialisation has a large effect on projected future sea-level contributions and gives rise to important uncertainties. The goal of this intercomparison exercise for the continental-scale Greenland ice sheet is therefore to compare, evaluate and improve the initialisation techniques used in the ice sheet modelling community. The initMIP-Greenland project is the first in a series of ice sheet model intercomparison activities within ISMIP6 (Ice Sheet Model Intercomparison Project for CMIP6). The experimental set-up has been designed to allow comparison of the initial present-day state of the Greenland ice sheet between participating models and against observations. Furthermore, the initial states are tested with two schematic forward experiments to evaluate the initialisation in terms of model drift (forward run without any forcing) and response to a large perturbation (prescribed surface mass balance anomaly). We present and discuss results that highlight the wide diversity of data sets, boundary conditions and initialisation techniques used in the community to generate initial states of the Greenland ice sheet.

The Earth System (ES-DOC) Project

NASA Astrophysics Data System (ADS)

Greenslade, Mark; Murphy, Sylvia; Treshansky, Allyn; DeLuca, Cecilia; Guilyardi, Eric; Denvil, Sebastien

2014-05-01

ESSI1.3 New Paradigms, Modelling, and International Collaboration Strategies for Earth System Sciences Earth System Documentation (ES-DOC) is an international project supplying tools & services in support of earth system documentation creation, analysis and dissemination. It is nurturing a sustainable standards based documentation eco-system that aims to become an integral part of the next generation of exa-scale dataset archives. ES-DOC leverages open source software and places end-user narratives at the heart of all it does. ES-DOC has initially focused upon nurturing the Earth System Model (ESM) documentation eco-system. Within this context ES-DOC leverages emerging documentation standards and supports the following projects: Coupled Model Inter-comparison Project Phase 5 (CMIP5); Dynamical Core Model Inter-comparison Project (DCMIP); National Climate Predictions and Projections Platforms Quantitative Evaluation of Downscaling Workshop. This presentation will introduce the project to a wider audience and demonstrate the range of tools and services currently available for use. It will also demonstrate how international collaborative efforts are essential to the success of ES-DOC.

Preparation and Current Situation of Proton-ICCHIBAN-2 Experiment

NASA Astrophysics Data System (ADS)

Uchihori, Yukio; Yasuda, Nakahiro; Kitamura, H.; Kodaira, S.; Benton, Eric; Hajek, Michael; Berger, Thomas; Jadrnickova, Iva; Ploc, Ondrej

The ICCHIBAN (Inter Comparison for Cosmicrays with Heavy Ion Beams at NIRS) working group has organized and performed various ICCHIBAN runs for active and passive radiation detectors at HIMAC, NIRS, Japan, Loma Linda and Brookhaven, USA and CERN, Switzer-land since the start of the ICCHIBAN project in the year 2002. One of the main focus points of this project is to understand the response of the applied detector systems (either active or passive) for personal and area dosimetry in space environment to a simulated sub-set of the space radiation environment, focusing on the heavy ion response. This is of special importance for the further intercomparison of space radiation data gathered by various international in-stitutes and universities for space radiation experiments as MATROSHKA, DOSIS, DOBIES, BRADOS, MATROSHKA-R etc. The ICCHIBAN experiments have created a big database of response data, especially for all the different passive radiation detectors and detector materials (Thermoluminescence (TLD) and Optical Luminescence (OSL)) over the last 7 years, resulting in a better understanding of how and why we still have differences in the measurement results from common space experiments -as the Space ICCHIBAN 2 experiment. One of the reasons why for the differences in the TLD/OSL results is the lack of intercomparison and response data for low LET particles up to around 10 keV/m, especially protons. Due to the fact, that the main contribution to absorbed dose in low earth orbit is due to protons, the ICCHIBAN working group has started the set-up of a Proton ICCHIBAN intercomparison experiment at NIRS. The Proton ICCHIBAN run has been performed at the cyclotron at NIRS, Chiba in February 2010. 15 institutes from 12 countries sent or brought their dosimeters and exposed them to 40 and 70 MeV proton beams with the same doses and exposure conditions. In this paper, the experiment procedures and current situation of the intercomparision experiments will be shown.

Emergent constraints on climate-carbon cycle feedbacks in the CMIP5 Earth system models

NASA Astrophysics Data System (ADS)

Wenzel, Sabrina; Cox, Peter M.; Eyring, Veronika; Friedlingstein, Pierre

2014-05-01

An emergent linear relationship between the long-term sensitivity of tropical land carbon storage to climate warming (γLT) and the short-term sensitivity of atmospheric carbon dioxide (CO2) to interannual temperature variability (γIAV) has previously been identified by Cox et al. (2013) across an ensemble of Earth system models (ESMs) participating in the Coupled Climate-Carbon Cycle Model Intercomparison Project (C4MIP). Here we examine whether such a constraint also holds for a new set of eight ESMs participating in Phase 5 of the Coupled Model Intercomparison Project. A wide spread in tropical land carbon storage is found for the quadrupling of atmospheric CO2, which is of the order of 252 ± 112 GtC when carbon-climate feedbacks are enabled. Correspondingly, the spread in γLT is wide (-49 ± 40 GtC/K) and thus remains one of the key uncertainties in climate projections. A tight correlation is found between the long-term sensitivity of tropical land carbon and the short-term sensitivity of atmospheric CO2 (γLT versus γIAV), which enables the projections to be constrained with observations. The observed short-term sensitivity of CO2 (-4.4 ± 0.9 GtC/yr/K) sharpens the range of γLT to -44 ± 14 GtC/K, which overlaps with the probability density function derived from the C4MIP models (-53 ± 17 GtC/K) by Cox et al. (2013), even though the lines relating γLT and γIAV differ in the two cases. Emergent constraints of this type provide a means to focus ESM evaluation against observations on the metrics most relevant to projections of future climate change.

INTERCOMPARISON OF OPTICAL REMOTE SENSING SYSTEMS FOR ROADSIDE MEASUREMENTS

EPA Science Inventory

The presentation describes results of an intercomparison of three optical remote sensing systems for measurements of nitric oxide emitted from passenger cars and light-duty trucks. The intercomparison included a standards comparison to establish comparability of standards, follo...

Hydrological and biogeochemical constraints on terrestrial carbon cycle feedbacks

NASA Astrophysics Data System (ADS)

Mystakidis, Stefanos; Seneviratne, Sonia I.; Gruber, Nicolas; Davin, Edouard L.

2017-01-01

The feedbacks between climate, atmospheric CO2 concentration and the terrestrial carbon cycle are a major source of uncertainty in future climate projections with Earth systems models. Here, we use observation-based estimates of the interannual variations in evapotranspiration (ET), net biome productivity (NBP), as well as the present-day sensitivity of NBP to climate variations, to constrain globally the terrestrial carbon cycle feedbacks as simulated by models that participated in the fifth phase of the coupled model intercomparison project (CMIP5). The constraints result in a ca. 40% lower response of NBP to climate change and a ca. 30% reduction in the strength of the CO2 fertilization effect relative to the unconstrained multi-model mean. While the unconstrained CMIP5 models suggest an increase in the cumulative terrestrial carbon storage (477 PgC) in response to an idealized scenario of 1%/year atmospheric CO2 increase, the constraints imply a ca. 19% smaller change. Overall, the applied emerging constraint approach offers a possibility to reduce uncertainties in the projections of the terrestrial carbon cycle, which is a key determinant of the future trajectory of atmospheric CO2 concentration and resulting climate change.

The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): Simulation design and preliminary results

DOE PAGES

Kravitz, Benjamin S.; Robock, Alan; Tilmes, S.; ...

2015-10-27

We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP). This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6), builds on the previous GeoMIP project simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more long wave radiation to escape to space. We discuss experiment designs, as well as the rationale formore » those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1) GeoMIP experiments. In conclusion, this is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.« less

Understanding the Asian summer monsoon response to greenhouse warming: the relative roles of direct radiative forcing and sea surface temperature change

NASA Astrophysics Data System (ADS)

Li, Xiaoqiong; Ting, Mingfang

2017-10-01

Future hydroclimate projections from state-of-the-art climate models show large uncertainty and model spread, particularly in the tropics and over the monsoon regions. The precipitation and circulation responses to rising greenhouse gases involve a fast component associated with direct radiative forcing and a slow component associated with sea surface temperature (SST) warming; the relative importance of the two may contribute to model discrepancies. In this study, regional hydroclimate responses to greenhouse warming are assessed using output from coupled general circulation models in the Coupled Model Intercomparison Project-Phase 5 (CMIP5) and idealized atmospheric general circulation model experiments from the Atmosphere Model Intercomparison Project. The thermodynamic and dynamic mechanisms causing the rainfall changes are examined using moisture budget analysis. Results show that direct radiative forcing and SST change exert significantly different responses both over land and ocean. For most part of the Asian monsoon region, the summertime rainfall changes are dominated by the direct CO2 radiative effect through enhanced monsoon circulation. The response to SST warming shows a larger model spread compared to direct radiative forcing, possibly due to the cancellation between the thermodynamical and dynamical components. While the thermodynamical response of the Asian monsoon is robust across the models, there is a lack of consensus for the dynamical response among the models and weak multi-model mean responses in the CMIP5 ensemble, which may be related to the multiple physical processes evolving on different time scales.

Field test to intercompare carbon monoxide, nitric oxide and hydroxyl instrumentation at Wallops Island, Virginia

NASA Technical Reports Server (NTRS)

Gregory, Gerald L.; Beck, Sherwin M.; Bendura, Richard J.

1987-01-01

Documentation of the first of three instrument intercomparisons conducted as part of NASA Global Tropospheric Experiment/Chemical Instrumentation Test and Evaluation (GTE/CITE-1) is given. This ground-based intercomparison was conducted during July 1983 at NASA Wallops Flight Facility. Instruments intercompared included one laser system and three grab-sample approaches for CO; two chemiluminescent systems and one laser-induced fluorescent (LIF) technique for NO; and two different LIF systems and a radiochemical tracer technique for OH. The major objectives of this intercomparison was to intercompare ambient measurements of CO, NO, and OH at a common site by using techniques of fundamentally different detection principles and to identify any major biases among the techniques prior to intercomparison on an aircraft platform. Included in the report are comprehensive discussions of workshop requirements, philosophies, and operations as well as intercomparison analyses and results. In addition, the large body of nonintercomparison data incorporated into the workshop measurements is summarized. The report is an important source document for those interested in conducting similar large and complex intercomparison tests as well as those interested in using the data base for purposes other than instrument intercomparison.

Performance evaluation of Teledyne Geotech bivane

DOE Office of Scientific and Technical Information (OSTI.GOV)

Addis, R.P.

1986-05-13

The new production prototype bivane manufactured by Teledyne Geotech underwent tests to evaluate its performance and determine its suitability as a replacement for obsolete instrumentation presently on the SRP meteorological towers. The bivane performs well for routine observations for emergency response, as well as for most routine plume dispersion research to be conducted at SRL for the foreseeable future. It should also be suitable for providing an accurate and reliable meteorological data base for engineering and meteorological applications for the next ten years. The bivane was tested in a wind tunnel where its Damping Ratio was found to be 0.30more » (azimuth) and 0.29 (elevation), which contrasts with 0.4 claimed by the manufacturer's preliminary specifications. Although the measured damping is less than the optimum value (0.43), it is estimated that the bivane will be able to measure the turbulent parameters (standard deviation of azimuth and elevation) used in the SRP emergency response codes, within 8%. The bivane's suitability as a research tool for measuring turbulent fluxes was determined by comparison with results from a sonic anemometer. The mean bivane momentum flux measurements were within 5% of those of the sonic, averaged over all measured flux intensities, and within 10% of the sonic for fluxes less than or equal to -0.05 m/sup 2//s/sup 2/. During periods of low fluxes, such as may occur under stable nocturnal conditions, a higher damping ratio (approx. 0.4) and a smaller natural wavelength would improve the bivane response to high frequency turbulence. The cup anemometer paired with the bivane, also performed well in the tests. An intercomparison of wind speeds with those measured by the sonic anemometer showed a mean difference of only 1 cm/s (0.02 mph).« less

RESULTS FROM THE NORTH AMERICAN MERCURY MODEL INTER-COMPARISON STUDY (NAMMIS)

EPA Science Inventory

A North American Mercury Model Intercomparison Study (NAMMIS) has been conducted to build upon the findings from previous mercury model intercomparison in Europe. In the absence of mercury measurement networks sufficient for model evaluation, model developers continue to rely on...

Accuracy of tretyakov precipitation gauge: Result of wmo intercomparison

USGS Publications Warehouse

Yang, Daqing; Goodison, Barry E.; Metcalfe, John R.; Golubev, Valentin S.; Elomaa, Esko; Gunther, Thilo; Bates, Roy; Pangburn, Timothy; Hanson, Clayton L.; Emerson, Douglas G.; Copaciu, Voilete; Milkovic, Janja

1995-01-01

The Tretyakov non-recording precipitation gauge has been used historically as the official precipitation measurement instrument in the Russian (formerly the USSR) climatic and hydrological station network and in a number of other European countries. From 1986 to 1993, the accuracy and performance of this gauge were evaluated during the WMO Solid Precipitation Measurement Intercomparison at 11 stations in Canada, the USA, Russia, Germany, Finland, Romania and Croatia. The double fence intercomparison reference (DFIR) was the reference standard used at all the Intercomparison stations in the Intercomparison. The Intercomparison data collected at the different sites are compatible with respect to the catch ratio (measured/DFIR) for the same gauge, when compared using mean wind speed at the height of the gauge orifice during the observation period.The Intercomparison data for the Tretyakov gauge were compiled from measurements made at these WMO intercomparison sites. These data represent a variety of climates, terrains and exposures. The effects of environmental factors, such as wind speed, wind direction, type of precipitation and temperature, on gauge catch ratios were investigated. Wind speed was found to be the most important factor determining the gauge catch and air temperature had a secondary effect when precipitation was classified into snow, mixed and rain. The results of the analysis of gauge catch ratio versus wind speed and temperature on a daily time step are presented for various types of precipitation. Independent checks of the correction equations against the DFIR have been conducted at those Intercomparison stations and a good agreement (difference less than 10%) has been obtained. The use of such adjustment procedures should significantly improve the accuracy and homogeneity of gauge-measured precipitation data over large regions of the former USSR and central Europe.

Operational overview of NASA GTE/CITE 1 airborne instrument intercomparisons - Carbon monoxide, nitric oxide, and hydroxyl instrumentation. [Global Tropospheric Experiment/Chemical Instrumentation Test and Evaluation

NASA Technical Reports Server (NTRS)

Beck, Sherwin M.; Bendura, Richard J.; Mcdougal, David S.; Hoell, James M., Jr.; Gregory, Gerald L.; Sachse, Glen W.; Hill, Gerald F.; Curfman, Howard J., Jr.; Torres, Arnold L.; Condon, Estelle P.

1987-01-01

An overview of the airborne intercomparisons of CO, NO, and OH instrumentation is presented in this first paper of the series on the NASA Global Tropospheric Experiment/Chemical Instrumentation Test and Evaluation (GTE/CITE 1). This paper provides the reader with background information about several important characteristics of the project. These include the overall objectives and approach, the measurements taken, the intercomparison protocol, aircraft platform, profiles of each aircraft flight, and the participants. A synopsis of the overall results of the CO, NO, and OH instrument intercomparisons is also included. Companion papers discuss the detailed results of the CO and NO intercomparison tests as well as pertinent scientific findings.

THE WORKSHOP ON THE SOURCE APPORTIONMENT OF PM HEALTH EFFECTS: INTER-COMPARISON OF RESULTS AND IMPLICATIONS

EPA Science Inventory

While the association between exposure to ambient fine particulate matter mass (PM2.5) and human mortality is well established, the most responsible particle types/sources are not yet certain. In May 2003, the U.S. Environmental Protection Agency's Particulate Matter Centers Prog...

Predicting maize phenology: Intercomparison of functions for developmental response to temperature

USDA-ARS?s Scientific Manuscript database

Accurate prediction of phenological development in maize is fundamental to determining crop adaptation and yield potential. A number of thermal functions are used in crop models, but their relative precision in predicting maize development has not been quantified. The objectives of this study were t...

The agricultural model intercomparison and improvement project (AgMIP): Protocols and pilot studies

USDA-ARS?s Scientific Manuscript database

The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a distributed climate-scenario simulation research activity for historical period model intercomparison and future climate change conditions with participation of multiple crop and agricultural economic model groups around the...

Intercomparisons of nine sky brightness detectors.

PubMed

den Outer, Peter; Lolkema, Dorien; Haaima, Marty; van der Hoff, Rene; Spoelstra, Henk; Schmidt, Wim

2011-01-01

Nine Sky Quality Meters (SQMs) have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across The Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between ±14%. Individual night time sums range from -16% to +20%. Intercalibration reduces this to 0.5%, and -7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 ± 0.003 mcd/m(2) on 12 April, and the largest value was 5.94 ± 0.03 mcd/m(2) on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.

Uncertainty in Twenty-First-Century CMIP5 Sea Level Projections

NASA Technical Reports Server (NTRS)

Little, Christopher M.; Horton, Radley M.; Kopp, Robert E.; Oppenheimer, Michael; Yip, Stan

2015-01-01

The representative concentration pathway (RCP) simulations included in phase 5 of the Coupled Model Intercomparison Project (CMIP5) quantify the response of the climate system to different natural and anthropogenic forcing scenarios. These simulations differ because of 1) forcing, 2) the representation of the climate system in atmosphere-ocean general circulation models (AOGCMs), and 3) the presence of unforced (internal) variability. Global and local sea level rise projections derived from these simulations, and the emergence of distinct responses to the four RCPs depend on the relative magnitude of these sources of uncertainty at different lead times. Here, the uncertainty in CMIP5 projections of sea level is partitioned at global and local scales, using a 164-member ensemble of twenty-first-century simulations. Local projections at New York City (NYSL) are highlighted. The partition between model uncertainty, scenario uncertainty, and internal variability in global mean sea level (GMSL) is qualitatively consistent with that of surface air temperature, with model uncertainty dominant for most of the twenty-first century. Locally, model uncertainty is dominant through 2100, with maxima in the North Atlantic and the Arctic Ocean. The model spread is driven largely by 4 of the 16 AOGCMs in the ensemble; these models exhibit outlying behavior in all RCPs and in both GMSL and NYSL. The magnitude of internal variability varies widely by location and across models, leading to differences of several decades in the local emergence of RCPs. The AOGCM spread, and its sensitivity to model exclusion and/or weighting, has important implications for sea level assessments, especially if a local risk management approach is utilized.

Pulmonary Function Response to Exposure to Low Concentration Ozone in Young Adults: Inter-comparison among Studies and Meta-Analysis

EPA Science Inventory

Rationale: It is well established that moderate ozone exposures induce decrements in spirometry volume and respiratory symptoms in healthy young adults. However, studies for low concentration ozone near the current NAAQS standard (0.070 ppm) are limited to only a few and their co...

Atmospheric Blocking and Intercomparison of Objective Detection Methods: Flow Field Characteristics

NASA Astrophysics Data System (ADS)

Pinheiro, M. C.; Ullrich, P. A.; Grotjahn, R.

2017-12-01

A number of objective methods for identifying and quantifying atmospheric blocking have been developed over the last couple of decades, but there is variable consensus on the resultant blocking climatology. This project examines blocking climatologies as produced by three different methods: two anomaly-based methods, and the geopotential height gradient method of Tibaldi and Molteni (1990). The results highlight the differences in blocking that arise from the choice of detection method, with emphasis on the physical characteristics of the flow field and the subsequent effects on the blocking patterns that emerge.

The First SIMBIOS Radiometric Intercomparison (SIMRIC-1), April-September 2001

NASA Technical Reports Server (NTRS)

Meister, Gerhard; Abel, Peter; McClain, Charles; Barnes, Robert; Fargion, Giulietta; Cooper, John; Davis, Curtiss; Korwan, Daniel; Godin, Mike; Maffione, Robert

2002-01-01

This report describes the first SIMBIOS (Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies) Radiometric Intercomparison (SIMRIC-1). The purpose of the SIMRIC-1 is to ensure a common radiometric scale of the calibration facilities that are engaged in calibrating in situ radiometers used for ocean color related research and to document the calibration procedures and protocols. SIMBIOS staff visited the seven participating laboratories for at least two days each. The SeaWiFS Transfer Radiometer SXR-II measured the calibration radiances produced in the laboratories. The measured radiances were compared with the radiances expected by the laboratories. Typically, the measured radiances were higher than the expected radiances by 0 to 2%. This level of agreement is satisfactory. Several issues were identified, where the calibration protocols need to be improved, especially the reflectance calibration of the reference plaques and the distance correction when using the irradiance standards at distances greater than the 50 cm. The responsivity of the SXR-II changed between 0.3% (channel 6) and 1.6% (channel 2) from December 2000 to December 2001. Monitoring the SXR-II with a portable light source showed a linear drift of the calibration, except for channel 1, where a 2% drop occurred in summer.

Comprehensive Australasian multicentre dosimetric intercomparison: issues, logistics and recommendations.

PubMed

Ebert, M A; Harrison, K M; Cornes, D; Howlett, S J; Joseph, D J; Kron, T; Hamilton, C S; Denham, J W

2009-02-01

The present paper describes the logistics of the 2004-2008 Australasian Level III Dosimetry Intercomparison. Dosimetric intercomparisons (or 'audits') can be used in radiotherapy to evaluate the accuracy and quality of radiation delivery. An intercomparison was undertaken in New Zealand and Australia to evaluate the feasibility and logistics of ongoing dosimetric intercomparisons that evaluate all steps in the radiotherapy treatment process, known as a 'Level III' intercomparison. The study commenced in 2002 with the establishment of a study team, definition of the study protocol, acquisition of appropriate equipment and recruitment of participating radiotherapy centres. Measurements were undertaken between October 2004 and March 2008, and included collation of data on time, costs and logistics of the study. Forty independent Australian and New Zealand radiotherapy centres agreed to participate. Measurement visits were made to 37 of these centres. Data is presented on the costs of the study and the level of support required. The study involved the participation of 16 staff at the study centre who invested over 4000 hours in the study, and of over 200 professionals at participating centres. Recommendations are provided for future phantom-based intercomparisons. It is hoped that the present paper will be of benefit to any centres or groups contemplating similar activities by identifying the processes involved in establishing the study, the potential hazards and pitfalls, and expected resource requirements.

2014 ICHLNRRA intercomparison of radon/thoron gas and radon short-lived decay products measuring instruments in the NRPI Prague.

PubMed

Jílek, K; Timková, J

2015-06-01

During the Eighth International Conference on High Levels of Natural Radiation and Radon Areas held in autumn 2014 at Prague, the third intercomparison of radon/thoron gas and radon short-lived decay products measurement instruments was organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI; SÚRO v.v.i.) in Prague. The intercomparison was newly focussed also on continuous monitors with active sampling adapters capable to distinguish radon/thoron gas in their mix field.The results of radon gas measurements carried out in the big NRPI radon chamber indicated very well an average deviation of up to 5 % from the reference NRPI value for 80 % of all the exposed instruments. The results of equilibrium equivalent concentration continuous monitors indicated an average deviation of up to 5 % from the reference NRPI value for 40 % of all the exposed instruments and their ~8-10 % shift compared with the NRPI. The results of investigated ambient conditions upon response of exposed continuous monitors indicated influence of aerosol changes upon response of radon monitors with an active air sampling adapters through the filter, only. The exposures of both radon/thoron gas discriminative continuous monitors and passive detectors have been indicated inconsistent results: on one hand, their excellent agreement up to several per cent for both the gases, and on the other hand, systematic unsatisfactory differences up to 40 %. Additional radon/thoron exercises are recommended to improve both the instruments themselves and quality of their operators. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Recommendations for diagnosing effective radiative forcing from climate models for CMIP6

DOE PAGES

Forster, Piers M.; Richardson, Thomas; Maycock, Amanda C.; ...

2016-10-27

The usefulness of previous Coupled Model Intercomparison Project (CMIP) exercises has been hampered by a lack of radiative forcing information. This has made it difficult to understand reasons for differences between model responses. Effective radiative forcing (ERF) is easier to diagnose than traditional radiative forcing in global climate models (GCMs) and is more representative of the eventual temperature response. Here we examine the different methods of computing ERF in two GCMs. We find that ERF computed from a fixed sea surface temperature (SST) method (ERF_fSST) has much more certainty than regression based methods. Thirty year integrations are sufficient to reducemore » the 5–95% confidence interval in global ERF_fSST to 0.1Wm ~2. For 2xCO2 ERF, 30 year integrations are needed to ensure that the signal is larger than the local confidence interval over more than 90% of the globe. Within the ERF_fSST method there are various options for prescribing SSTs and sea ice. We explore these and find that ERF is only weakly dependent on the methodological choices. Prescribing the monthly averaged seasonally varying model’s preindustrial climatology is recommended for its smaller random error and easier implementation. As part of CMIP6, the Radiative Forcing Model Intercomparison Project (RFMIP) asks models to conduct 30 year ERF_fSST experiments using the model’s own preindustrial climatology of SST and sea ice. The Aerosol and Chemistry Model Intercomparison Project (AerChemMIP) will also mainly use this approach. Lastly, we propose this as a standard method for diagnosing ERF and recommend that it be used across the climate modeling community to aid future comparisons.« less

Recommendations for diagnosing effective radiative forcing from climate models for CMIP6

DOE Office of Scientific and Technical Information (OSTI.GOV)

Forster, Piers M.; Richardson, Thomas; Maycock, Amanda C.

The usefulness of previous Coupled Model Intercomparison Project (CMIP) exercises has been hampered by a lack of radiative forcing information. This has made it difficult to understand reasons for differences between model responses. Effective radiative forcing (ERF) is easier to diagnose than traditional radiative forcing in global climate models (GCMs) and is more representative of the eventual temperature response. Here we examine the different methods of computing ERF in two GCMs. We find that ERF computed from a fixed sea surface temperature (SST) method (ERF_fSST) has much more certainty than regression based methods. Thirty year integrations are sufficient to reducemore » the 5–95% confidence interval in global ERF_fSST to 0.1Wm ~2. For 2xCO2 ERF, 30 year integrations are needed to ensure that the signal is larger than the local confidence interval over more than 90% of the globe. Within the ERF_fSST method there are various options for prescribing SSTs and sea ice. We explore these and find that ERF is only weakly dependent on the methodological choices. Prescribing the monthly averaged seasonally varying model’s preindustrial climatology is recommended for its smaller random error and easier implementation. As part of CMIP6, the Radiative Forcing Model Intercomparison Project (RFMIP) asks models to conduct 30 year ERF_fSST experiments using the model’s own preindustrial climatology of SST and sea ice. The Aerosol and Chemistry Model Intercomparison Project (AerChemMIP) will also mainly use this approach. Lastly, we propose this as a standard method for diagnosing ERF and recommend that it be used across the climate modeling community to aid future comparisons.« less

Recommendations for diagnosing effective radiative forcing from climate models for CMIP6

NASA Astrophysics Data System (ADS)

Smith, C. J.; Forster, P.; Richardson, T.; Myhre, G.; Pincus, R.

2016-12-01

The usefulness of previous Coupled Model Intercomparison Project (CMIP) exercises has been hampered by a lack of radiative forcing information. This has made it difficult to understand reasons for differences between model responses. Effective radiative forcing (ERF) is easier to diagnose than traditional radiative forcing in global climate models (GCMs) and is more representative of the ultimate climate response. Here we examine the different methods of computing ERF in two GCMs. We find that ERF computed from a fixed sea-surface temperature (SST) method (ERF_fSST) has much more certainty than regression-based methods. Thirty-year integrations are sufficient to reduce the standard error in global ERF to 0.05 Wm-2. For 2xCO2 ERF, 30 year integrations are needed to ensure that the signal is larger than the standard error over more than 90% of the globe. Within the ERF_fSST method there are various options for prescribing SSTs and sea-ice. We explore these and find that ERF is only weakly dependent on the methodological choices. Prescribing the monthly-averaged seasonally varying model's preindustrial climatology is recommended for its smaller random error and easier implementation. As part of CMIP6, the Radiative Forcing Model Intercomparison Project (RFMIP) asks models to conduct 30-year ERF_fSST experiments using the model's own preindustrial climatology of SST and sea-ice. The Aerosol and Chemistry Model intercomparison Project (AerChemMIP) will also mainly use this approach. We propose this as a standard method for diagnosing ERF in models and recommend that it be used across the climate modeling community to aid future comparisons.

Recommendations for diagnosing effective radiative forcing from climate models for CMIP6

NASA Astrophysics Data System (ADS)

Forster, Piers M.; Richardson, Thomas; Maycock, Amanda C.; Smith, Christopher J.; Samset, Bjorn H.; Myhre, Gunnar; Andrews, Timothy; Pincus, Robert; Schulz, Michael

2016-10-01

The usefulness of previous Coupled Model Intercomparison Project (CMIP) exercises has been hampered by a lack of radiative forcing information. This has made it difficult to understand reasons for differences between model responses. Effective radiative forcing (ERF) is easier to diagnose than traditional radiative forcing in global climate models (GCMs) and is more representative of the eventual temperature response. Here we examine the different methods of computing ERF in two GCMs. We find that ERF computed from a fixed sea surface temperature (SST) method (ERF_fSST) has much more certainty than regression based methods. Thirty year integrations are sufficient to reduce the 5-95% confidence interval in global ERF_fSST to 0.1 W m-2. For 2xCO2 ERF, 30 year integrations are needed to ensure that the signal is larger than the local confidence interval over more than 90% of the globe. Within the ERF_fSST method there are various options for prescribing SSTs and sea ice. We explore these and find that ERF is only weakly dependent on the methodological choices. Prescribing the monthly averaged seasonally varying model's preindustrial climatology is recommended for its smaller random error and easier implementation. As part of CMIP6, the Radiative Forcing Model Intercomparison Project (RFMIP) asks models to conduct 30 year ERF_fSST experiments using the model's own preindustrial climatology of SST and sea ice. The Aerosol and Chemistry Model Intercomparison Project (AerChemMIP) will also mainly use this approach. We propose this as a standard method for diagnosing ERF and recommend that it be used across the climate modeling community to aid future comparisons.

Intercomparison of hydrologic processes in global climate models

NASA Technical Reports Server (NTRS)

Lau, W. K.-M.; Sud, Y. C.; Kim, J.-H.

1995-01-01

In this report, we address the intercomparison of precipitation (P), evaporation (E), and surface hydrologic forcing (P-E) for 23 Atmospheric Model Intercomparison Project (AMIP) general circulation models (GCM's) including relevant observations, over a variety of spatial and temporal scales. The intercomparison includes global and hemispheric means, latitudinal profiles, selected area means for the tropics and extratropics, ocean and land, respectively. In addition, we have computed anomaly pattern correlations among models and observations for different seasons, harmonic analysis for annual and semiannual cycles, and rain-rate frequency distribution. We also compare the joint influence of temperature and precipitation on local climate using the Koeppen climate classification scheme.

Airborne sulfur trace species intercomparison campaign: Sulfur dioxide, dimethylsulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide

NASA Technical Reports Server (NTRS)

Gregory, Gerald L.; Hoell, James M., Jr.; Davis, Douglas D.

1991-01-01

Results from an airborne intercomparison of techniques to measure tropospheric levels of sulfur trace gases are presented. The intercomparison was part of the NASA Global Tropospheric Experiment (GTE) and was conducted during the summer of 1989. The intercomparisons were conducted on the Wallops Electra aircraft during flights from Wallops Island, Virginia, and Natal, Brazil. Sulfur measurements intercompared included sulfur dioxide (SO2), dimethylsulfide (DMS), hydrogen sulfide (H2S), carbon disulfide (CS2), and carbonyl sulfide (OCS). Measurement techniques ranged from filter collection systems with post-flight analyses to mass spectrometer and gas chromatograph systems employing various methods for measuring and identifying the sulfur gases during flight. Sampling schedules for the techniques ranged from integrated collections over periods as long as 50 minutes to one- to three-minute samples every ten or fifteen minutes. Several of the techniques provided measurements of more than one sulfur gas. Instruments employing different detection principles were involved in each of the sulfur intercomparisons. Also included in the intercomparison measurement scenario were a host of supporting measurements (i.e., ozone, nitrogen oxides, carbon monoxide, total sulfur, aerosols, etc.) for purposes of: (1) interpreting results (i.e., correlation of any noted instrument disagreement with the chemical composition of the measurement environment); and (2) providing supporting chemical data to meet CITE-3 science objectives of studying ozone/sulfur photochemistry, diurnal cycles, etc. The results of the intercomparison study are briefly discussed.

DCMIP2016: a review of non-hydrostatic dynamical core design and intercomparison of participating models

NASA Astrophysics Data System (ADS)

Ullrich, Paul A.; Jablonowski, Christiane; Kent, James; Lauritzen, Peter H.; Nair, Ramachandran; Reed, Kevin A.; Zarzycki, Colin M.; Hall, David M.; Dazlich, Don; Heikes, Ross; Konor, Celal; Randall, David; Dubos, Thomas; Meurdesoif, Yann; Chen, Xi; Harris, Lucas; Kühnlein, Christian; Lee, Vivian; Qaddouri, Abdessamad; Girard, Claude; Giorgetta, Marco; Reinert, Daniel; Klemp, Joseph; Park, Sang-Hun; Skamarock, William; Miura, Hiroaki; Ohno, Tomoki; Yoshida, Ryuji; Walko, Robert; Reinecke, Alex; Viner, Kevin

2017-12-01

Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier-Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and their individual successes suggest that no perfect model exists. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 non-hydrostatic dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP) workshop and summer school. This review includes a choice of model grid, variable placement, vertical coordinate, prognostic equations, temporal discretization, and the diffusion, stabilization, filters, and fixers employed by each system.

Using Ecosystem Experiments to Improve Vegetation Models

DOE PAGES

Medlyn, Belinda; Zaehle, S; DeKauwe, Martin G.; ...

2015-05-21

Ecosystem responses to rising CO2 concentrations are a major source of uncertainty in climate change projections. Data from ecosystem-scale Free-Air CO2 Enrichment (FACE) experiments provide a unique opportunity to reduce this uncertainty. The recent FACE Model–Data Synthesis project aimed to use the information gathered in two forest FACE experiments to assess and improve land ecosystem models. A new 'assumption-centred' model intercomparison approach was used, in which participating models were evaluated against experimental data based on the ways in which they represent key ecological processes. Identifying and evaluating the main assumptions caused differences among models, and the assumption-centered approach produced amore » clear roadmap for reducing model uncertainty. We explain this approach and summarize the resulting research agenda. We encourage the application of this approach in other model intercomparison projects to fundamentally improve predictive understanding of the Earth system.« less

Intercomparison of land-surface parameterizations launched

NASA Astrophysics Data System (ADS)

Henderson-Sellers, A.; Dickinson, R. E.

One of the crucial tasks for climatic and hydrological scientists over the next several years will be validating land surface process parameterizations used in climate models. There is not, necessarily, a unique set of parameters to be used. Different scientists will want to attempt to capture processes through various methods “for example, Avissar and Verstraete, 1990”. Validation of some aspects of the available (and proposed) schemes' performance is clearly required. It would also be valuable to compare the behavior of the existing schemes [for example, Dickinson et al., 1991; Henderson-Sellers, 1992a].The WMO-CAS Working Group on Numerical Experimentation (WGNE) and the Science Panel of the GEWEX Continental-Scale International Project (GCIP) [for example, Chahine, 1992] have agreed to launch the joint WGNE/GCIP Project for Intercomparison of Land-Surface Parameterization Schemes (PILPS). The principal goal of this project is to achieve greater understanding of the capabilities and potential applications of existing and new land-surface schemes in atmospheric models. It is not anticipated that a single “best” scheme will emerge. Rather, the aim is to explore alternative models in ways compatible with their authors' or exploiters' goals and to increase understanding of the characteristics of these models in the scientific community.

An energetic perspective on hydrological cycle changes in the Geoengineering Model Intercomparison Project

NASA Astrophysics Data System (ADS)

Kravitz, Ben; Rasch, Philip J.; Forster, Piers M.; Andrews, Timothy; Cole, Jason N. S.; Irvine, Peter J.; Ji, Duoying; Kristjánsson, Jón Egill; Moore, John C.; Muri, Helene; Niemeier, Ulrike; Robock, Alan; Singh, Balwinder; Tilmes, Simone; Watanabe, Shingo; Yoon, Jin-Ho

2013-12-01

of surface and atmospheric energy budget responses to CO2 and solar forcings can be used to reveal mechanisms of change in the hydrological cycle. We apply this energetic perspective to output from 11 fully coupled atmosphere-ocean general circulation models simulating experiment G1 of the Geoengineering Model Intercomparison Project (GeoMIP), which achieves top-of-atmosphere energy balance between an abrupt quadrupling of CO2 from preindustrial levels (abrupt4xCO2) and uniform solar irradiance reduction. We divide the climate system response into a rapid adjustment, in which climate response is due to adjustment of the atmosphere and land surface on short time scales, and a feedback response, in which the climate response is predominantly due to feedback related to global mean temperature changes. Global mean temperature change is small in G1, so the feedback response is also small. G1 shows a smaller magnitude of land sensible heat flux rapid adjustment than in abrupt4xCO2 and a larger magnitude of latent heat flux adjustment, indicating a greater reduction of evaporation and less land temperature increase than abrupt4xCO2. The sum of surface flux changes in G1 is small, indicating little ocean heat uptake. Using an energetic perspective to assess precipitation changes, abrupt4xCO2 shows decreased mean evaporative moisture flux and increased moisture convergence, particularly over land. However, most changes in precipitation in G1 are in mean evaporative flux, suggesting that changes in mean circulation are small.

Pliocene Model Intercomparison Project (PlioMIP): Experimental Design and Boundary Conditions (Experiment 2)

NASA Technical Reports Server (NTRS)

Haywood, A. M.; Dowsett, H. J.; Robinson, M. M.; Stoll, D. K.; Dolan, A. M.; Lunt, D. J.; Otto-Bliesner, B.; Chandler, M. A.

2011-01-01

The Palaeoclimate Modelling Intercomparison Project has expanded to include a model intercomparison for the mid-Pliocene warm period (3.29 to 2.97 million yr ago). This project is referred to as PlioMIP (the Pliocene Model Intercomparison Project). Two experiments have been agreed upon and together compose the initial phase of PlioMIP. The first (Experiment 1) is being performed with atmosphere only climate models. The second (Experiment 2) utilizes fully coupled ocean-atmosphere climate models. Following on from the publication of the experimental design and boundary conditions for Experiment 1 in Geoscientific Model Development, this paper provides the necessary description of differences and/or additions to the experimental design for Experiment 2.

Pliocene Model Intercomparison Project (PlioMIP): experimental design and boundary conditions (Experiment 2)

USGS Publications Warehouse

Haywood, A.M.; Dowsett, H.J.; Robinson, M.M.; Stoll, D.K.; Dolan, A.M.; Lunt, D.J.; Otto-Bliesner, B.; Chandler, M.A.

2011-01-01

The Palaeoclimate Modelling Intercomparison Project has expanded to include a model intercomparison for the mid-Pliocene warm period (3.29 to 2.97 million yr ago). This project is referred to as PlioMIP (the Pliocene Model Intercomparison Project). Two experiments have been agreed upon and together compose the initial phase of PlioMIP. The first (Experiment 1) is being performed with atmosphere-only climate models. The second (Experiment 2) utilises fully coupled ocean-atmosphere climate models. Following on from the publication of the experimental design and boundary conditions for Experiment 1 in Geoscientific Model Development, this paper provides the necessary description of differences and/or additions to the experimental design for Experiment 2.

Manufacture and calibration of optical supersmooth roughness artifacts for intercomparisons

NASA Astrophysics Data System (ADS)

Ringel, Gabriele A.; Kratz, Frank; Schmitt, Dirk-Roger; Mangelsdorf, Juergen; Creuzet, Francois; Garratt, John D.

1995-09-01

Intercomparison roughness measurements have been carried out on supersmooth artifacts fabricated from BK7, fused silica, and Zerodur. The surface parameters were determined using the optical heterodyne profiler Z5500 (Zygo), a special prototype of the mechanical profiler Nanostep (Rank Taylor Hobson), and an Atomic Force Microscope (Park Scientific Instruments) with an improved acquisition technique. The intercomparison was performed after the range of collected spatial wavelengths for each instrument was adjusted using digital filtering techniques. It is demonstrated for different roughness ranges that the applied superpolishing techniques yield supersmooth artifacts which can be used for more intercomparisons. More than 100 samples were investigated. Criteria were developed to select artifacts from the sample stock.

Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janik, M., E-mail: mirek@fml.nirs.go.jp; Ishikawa, T.; Omori, Y.

Inhalation of radon ({sup 222}Rn) and its short-lived decay products and of products of the thoron ({sup 220}Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercisesmore » were carried out in the 24.4 m{sup 3} inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm{sup 3} inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the present status on radon and thoron passive, one-time cycle monitors.« less

[Implementation of quality standard UNE-EN ISO/IEC 17043 in the External Quality Control Program of the Spanish Society of Infectious Diseases and Clinical Microbiology].

PubMed

Poveda Gabaldón, Marta; Ovies, María Rosario; Orta Mira, Nieves; Serrano, M del Remedio Guna; Avila, Javier; Giménez, Alicia; Cardona, Concepción Gimeno

2011-12-01

The quality standard "UNE-EN-ISO 17043: 2010. Conformity assessment. General requirements for proficiency testing" applies to centers that organize intercomparisons in all areas. In the case of clinical microbiology laboratories, these intercomparisons must meet the management and technical standards required to achieve maximum quality in the performance of microbiological analysis and the preparation of test items (sample, product, data or other information used in the proficiency test) to enable them to be accredited. Once accredited, these laboratories can operate as a tool for quality control laboratories and competency assessment. In Spain, accreditation is granted by the Spanish Accreditation Body [Entidad Nacional de Acreditación (ENAC)]. The objective of this review is to explain how to apply the requirements of the standard to laboratories providing intercomparisons in the field of clinical microbiology (the organization responsible for all the tasks related to the development and operation of a proficiency testing program). This requires defining the scope and specifying the technical requirements (personnel management, control of equipment, facilities and environment, the design of the proficiency testing and data analysis for performance evaluation, communication with participants and confidentiality) and management requirements (document control, purchasing control, monitoring of complaints / claims, non-compliance, internal audits and management reviews). Copyright © 2011 Elsevier España S.L. All rights reserved.

C4MIP - The Coupled Climate-Carbon Cycle Model Intercomparison Project: experimental protocol for CMIP6

NASA Astrophysics Data System (ADS)

Jones, Chris D.; Arora, Vivek; Friedlingstein, Pierre; Bopp, Laurent; Brovkin, Victor; Dunne, John; Graven, Heather; Hoffman, Forrest; Ilyina, Tatiana; John, Jasmin G.; Jung, Martin; Kawamiya, Michio; Koven, Charlie; Pongratz, Julia; Raddatz, Thomas; Randerson, James T.; Zaehle, Sönke

2016-08-01

Coordinated experimental design and implementation has become a cornerstone of global climate modelling. Model Intercomparison Projects (MIPs) enable systematic and robust analysis of results across many models, by reducing the influence of ad hoc differences in model set-up or experimental boundary conditions. As it enters its 6th phase, the Coupled Model Intercomparison Project (CMIP6) has grown significantly in scope with the design and documentation of individual simulations delegated to individual climate science communities. The Coupled Climate-Carbon Cycle Model Intercomparison Project (C4MIP) takes responsibility for design, documentation, and analysis of carbon cycle feedbacks and interactions in climate simulations. These feedbacks are potentially large and play a leading-order contribution in determining the atmospheric composition in response to human emissions of CO2 and in the setting of emissions targets to stabilize climate or avoid dangerous climate change. For over a decade, C4MIP has coordinated coupled climate-carbon cycle simulations, and in this paper we describe the C4MIP simulations that will be formally part of CMIP6. While the climate-carbon cycle community has created this experimental design, the simulations also fit within the wider CMIP activity, conform to some common standards including documentation and diagnostic requests, and are designed to complement the CMIP core experiments known as the Diagnostic, Evaluation and Characterization of Klima (DECK). C4MIP has three key strands of scientific motivation and the requested simulations are designed to satisfy their needs: (1) pre-industrial and historical simulations (formally part of the common set of CMIP6 experiments) to enable model evaluation, (2) idealized coupled and partially coupled simulations with 1 % per year increases in CO2 to enable diagnosis of feedback strength and its components, (3) future scenario simulations to project how the Earth system will respond to anthropogenic activity over the 21st century and beyond. This paper documents in detail these simulations, explains their rationale and planned analysis, and describes how to set up and run the simulations. Particular attention is paid to boundary conditions, input data, and requested output diagnostics. It is important that modelling groups participating in C4MIP adhere as closely as possible to this experimental design.

C4MIP – The Coupled Climate–Carbon Cycle Model Intercomparison Project: Experimental protocol for CMIP6

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Chris D.; Arora, Vivek; Friedlingstein, Pierre

Coordinated experimental design and implementation has become a cornerstone of global climate modelling. Model Intercomparison Projects (MIPs) enable systematic and robust analysis of results across many models, by reducing the influence of ad hoc differences in model set-up or experimental boundary conditions. As it enters its 6th phase, the Coupled Model Intercomparison Project (CMIP6) has grown significantly in scope with the design and documentation of individual simulations delegated to individual climate science communities. The Coupled Climate–Carbon Cycle Model Intercomparison Project (C4MIP) takes responsibility for design, documentation, and analysis of carbon cycle feedbacks and interactions in climate simulations. These feedbacks aremore » potentially large and play a leading-order contribution in determining the atmospheric composition in response to human emissions of CO 2 and in the setting of emissions targets to stabilize climate or avoid dangerous climate change. For over a decade, C4MIP has coordinated coupled climate–carbon cycle simulations, and in this paper we describe the C4MIP simulations that will be formally part of CMIP6. While the climate–carbon cycle community has created this experimental design, the simulations also fit within the wider CMIP activity, conform to some common standards including documentation and diagnostic requests, and are designed to complement the CMIP core experiments known as the Diagnostic, Evaluation and Characterization of Klima (DECK). C4MIP has three key strands of scientific motivation and the requested simulations are designed to satisfy their needs: (1) pre-industrial and historical simulations (formally part of the common set of CMIP6 experiments) to enable model evaluation, (2) idealized coupled and partially coupled simulations with 1 % per year increases in CO 2 to enable diagnosis of feedback strength and its components, (3) future scenario simulations to project how the Earth system will respond to anthropogenic activity over the 21st century and beyond. This study documents in detail these simulations, explains their rationale and planned analysis, and describes how to set up and run the simulations. Particular attention is paid to boundary conditions, input data, and requested output diagnostics. It is important that modelling groups participating in C4MIP adhere as closely as possible to this experimental design.« less

C4MIP – The Coupled Climate–Carbon Cycle Model Intercomparison Project: Experimental protocol for CMIP6

DOE PAGES

Jones, Chris D.; Arora, Vivek; Friedlingstein, Pierre; ...

2016-08-25

Coordinated experimental design and implementation has become a cornerstone of global climate modelling. Model Intercomparison Projects (MIPs) enable systematic and robust analysis of results across many models, by reducing the influence of ad hoc differences in model set-up or experimental boundary conditions. As it enters its 6th phase, the Coupled Model Intercomparison Project (CMIP6) has grown significantly in scope with the design and documentation of individual simulations delegated to individual climate science communities. The Coupled Climate–Carbon Cycle Model Intercomparison Project (C4MIP) takes responsibility for design, documentation, and analysis of carbon cycle feedbacks and interactions in climate simulations. These feedbacks aremore » potentially large and play a leading-order contribution in determining the atmospheric composition in response to human emissions of CO 2 and in the setting of emissions targets to stabilize climate or avoid dangerous climate change. For over a decade, C4MIP has coordinated coupled climate–carbon cycle simulations, and in this paper we describe the C4MIP simulations that will be formally part of CMIP6. While the climate–carbon cycle community has created this experimental design, the simulations also fit within the wider CMIP activity, conform to some common standards including documentation and diagnostic requests, and are designed to complement the CMIP core experiments known as the Diagnostic, Evaluation and Characterization of Klima (DECK). C4MIP has three key strands of scientific motivation and the requested simulations are designed to satisfy their needs: (1) pre-industrial and historical simulations (formally part of the common set of CMIP6 experiments) to enable model evaluation, (2) idealized coupled and partially coupled simulations with 1 % per year increases in CO 2 to enable diagnosis of feedback strength and its components, (3) future scenario simulations to project how the Earth system will respond to anthropogenic activity over the 21st century and beyond. This study documents in detail these simulations, explains their rationale and planned analysis, and describes how to set up and run the simulations. Particular attention is paid to boundary conditions, input data, and requested output diagnostics. It is important that modelling groups participating in C4MIP adhere as closely as possible to this experimental design.« less

How well do simulated last glacial maximum tropical temperatures constrain equilibrium climate sensitivity?

NASA Astrophysics Data System (ADS)

Hopcroft, Peter O.; Valdes, Paul J.

2015-07-01

Previous work demonstrated a significant correlation between tropical surface air temperature and equilibrium climate sensitivity (ECS) in PMIP (Paleoclimate Modelling Intercomparison Project) phase 2 model simulations of the last glacial maximum (LGM). This implies that reconstructed LGM cooling in this region could provide information about the climate system ECS value. We analyze results from new simulations of the LGM performed as part of Coupled Model Intercomparison Project (CMIP5) and PMIP phase 3. These results show no consistent relationship between the LGM tropical cooling and ECS. A radiative forcing and feedback analysis shows that a number of factors are responsible for this decoupling, some of which are related to vegetation and aerosol feedbacks. While several of the processes identified are LGM specific and do not impact on elevated CO2 simulations, this analysis demonstrates one area where the newer CMIP5 models behave in a qualitatively different manner compared with the older ensemble. The results imply that so-called Earth System components such as vegetation and aerosols can have a significant impact on the climate response in LGM simulations, and this should be taken into account in future analyses.

Pliocene Model Intercomparison (PlioMIP) Phase 2: Scientific Objectives and Experimental Design

NASA Technical Reports Server (NTRS)

Haywood, A. M.; Dowsett, H. J.; Dolan, A. M.; Rowley, D.; Abe-Ouchi, A.; Otto-Bliesner, B.; Chandler, M. A.; Hunter, S. J.; Lunt, D. J.; Pound, M.;

Assurance of MOZAIC/IAGOS relative humidity data quality by evaluating the Capacitive Hygrometer during airborne field studies

NASA Astrophysics Data System (ADS)

Neis, Patrick; Smit, Herman G. J.; Rohs, Susanne; Rolf, Christian; Krämer, Martina; Ebert, Volker; Buchholz, Bernhard; Bundke, Ulrich; Finger, Fanny; Klingebiel, Marcus; Petzold, Andreas

2015-04-01

Water vapour is a major parameter in weather prediction and climate research but the interaction between the water vapour in the upper troposphere and lowermost stratosphere (UT/LS) and tropopause dynamics are not well understood. A continuous measurement of upper tropospheric humidity (UTH) is difficult because the abundance of UTH is highly variable on spatial and temporal scales that cannot be resolved, neither by the global radiosondes network nor by satellites. Since 1994, data with high spatial and temporal resolution for relative humidity are provided by the in-situ measurements aboard civil passenger aircraft from the MOZAIC/IAGOS-programme (www.iagos.org). The data set emerging from this long-term observation effort builds the backbone of the ongoing in-situ UTH climatology and trend analyses. In order to assess the validity of the long-term water vapour data and its limitations, an analysis of the humidity data sets of two field campaigns is presented. The validation of applied measurement methods, i.e. the MOZAIC/IAGOS Capacitive Hygrometer, is valued on the basis of the aircraft campaigns CIRRUS-III (2006) and AIRTOSS-ICE (2013), where research-grade water vapour instruments were operated simultaneously to the MOZAIC/IAGOS Capacitive Hygrometers. The performance of the MOZAIC Capacitive Hygrometer (MCH; operated from 1994 to 2014 on MOZAIC aircraft) and the advanced IAGOS Capacitive Hygrometer (ICH; operated since 2011 on IAGOS aircraft) are explored in clear sky, in the vicinity of and inside cirrus clouds as a blind intercomparison to the research-grade water vapour instruments. From these intercomparisons the qualification of the Capacitive Hygrometer for the use in long-term observation programmes is successfully demonstrated and the continuation of high data quality is confirmed for the transition from MCH to ICH. In particular the Capacitive Hygrometer response time to changes in relative humidity could be determined for the full range of temperatures in the comparison against the research-grade instruments.

Agricultural response functions to changes in carbon, temperature, and water based on the C3MP data set

NASA Astrophysics Data System (ADS)

Snyder, A.; Ruane, A. C.; Phillips, M.; Calvin, K. V.; Clarke, L.

2017-12-01

Agricultural yields vary depending on temperature, precipitation/irrigation conditions, fertilizer application, and CO2 concentration. The Coordinated Climate-Crop Modeling Project (C3MP), conducted as a component of the Agricultural Model Intercomparison and Improvement Project (AgMIP), organized a sensitivity experiments across carbon-temperature-water (CTW) space across 1100 management conditions in 50+ countries, sampling 15 crop species and 20 crop models. Such coordinated sensitivity tests allow for the building of emulators of yield response to changes in CTW values, allowing rapid estimation of yield changes from the types of climate changes projected by the climate modeling community. The resulting emulator may be used to supply agricultural responses to climate change in any user-defined scenario, rather than the restriction to the RCPs in many past works. We present the resulting emulators built from the C3MP output data set for use in the Global Change Assessment Model (GCAM) integrated assessment model that allows for the co-evolution of socioeconomic development, greenhouse gas emissions, climate change, and agricultural sector ramifications. C3MP-based emulators may be of use in designing agricultural impact studies in other IAMs, and we place them in the context of past crop modeling efforts, including the Challinor et al. Meta-analysis, the AgMIP Wheat team results, the AgMIP Global Gridded Crop Model Intercomparison (GGCMI) fast-track modeling results, and the MACSUR impact response surface results.

Intercomparison of three microwave/infrared high resolution line-by-line radiative transfer codes

NASA Astrophysics Data System (ADS)

Schreier, F.; Garcia, S. Gimeno; Milz, M.; Kottayil, A.; Höpfner, M.; von Clarmann, T.; Stiller, G.

2013-05-01

An intercomparison of three line-by-line (lbl) codes developed independently for atmospheric sounding - ARTS, GARLIC, and KOPRA - has been performed for a thermal infrared nadir sounding application assuming a HIRS-like (High resolution Infrared Radiation Sounder) setup. Radiances for the HIRS infrared channels and a set of 42 atmospheric profiles from the "Garand dataset" have been computed. Results of this intercomparison and a discussion of reasons of the observed differences are presented.

An intercomparison of nitric oxide measurement techniques

NASA Technical Reports Server (NTRS)

Hoell, J. M., Jr.; Gregory, G. L.; Mcdougal, D. S.; Carroll, M. A.; Mcfarland, M.; Ridley, B. A.; Davis, D. D.; Bradshaw, J.; Rodgers, M. O.; Torres, A. L.

1985-01-01

Results from an intercomparison of techniques to measure tropospheric levels of nitric oxide (NO) are discussed. The intercomparison was part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and was conducted at Wallops Island, VA, in July 1983. Instruments intercompared included a laser-induced fluorescence system and two chemiluminescence instruments. The intercomparisons were performed with ambient air at NO mixing ratios ranging from 10 to 60 pptv and NO-enriched ambient air at mixing ratios from 20 to 170 pptv. All instruments sampled from a common manifold. The techniques exhibited a high degree of correlation among themselves and with changes in the NO mixing ratio. Agreement among the three techniques was placed at approximately + or - 30 percent. Within this level of agreement, no artifacts or species interferences were identified.

NRC TLD Direct Radiation Monitoring Network. Progress report, October--December 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

Struckmeyer, R.

This report presents the results of the NRC Direct Radiation Monitoring Network for the fourth quarter of 1996. It provides the ambient radiation levels measured in the vicinity of 74 sites throughout the United States. In addition, it describes the equipment used, monitoring station selection criteria, characterization of the dosimeter response, calibration procedures, statistical methods, intercomparison, and quality assurance program. 3 figs., 4 tabs.

Maximum warming occurs about one decade after carbon dioxide emission

NASA Astrophysics Data System (ADS)

Ricke, K.; Caldeira, K.

2014-12-01

There has been a long tradition of estimating the amount of climate change that would result from various carbon dioxide emission or concentration scenarios but there has been relatively little quantitative analysis of how long it takes to feel the consequences of an individual carbon dioxide emission. Using conjoined results of recent carbon-cycle and physical-climate model intercomparison projects, we find the median time between an emission and maximum warming is 10.1 years, with a 90% probability range of 6.6 to 30.7 years. We evaluate uncertainties in timing and amount of warming, partitioning them into three contributing factors: carbon cycle, climate sensitivity and ocean thermal inertia. To characterize the carbon cycle uncertainty associated with the global temperature response to a carbon dioxide emission today, we use fits to the time series of carbon dioxide concentrations from a CO2-impulse response function model intercomparison project's 15 ensemble members (1). To characterize both the uncertainty in climate sensitivity and in the thermal inertia of the climate system, we use fits to the time series of global temperature change from the Coupled Model Intercomparison Project phase 5 (CMIP5; 2) abrupt4xco2 experiment's 20 ensemble's members separating the effects of each uncertainty factors using one of two simple physical models for each CMIP5 climate model. This yields 6,000 possible combinations of these three factors using a standard convolution integral approach. Our results indicate that benefits of avoided climate damage from avoided CO2 emissions will be manifested within the lifetimes of people who acted to avoid that emission. While the relevant time lags imposed by the climate system are substantially shorter than a human lifetime, they are substantially longer than the typical political election cycle, making the delay and its associated uncertainties both economically and politically significant. References: 1. Joos F et al. (2013) Carbon dioxide and climate impulse response functions for the computation of greenhouse gas metrics: a multi-model analysis. Atmos Chem Phys 13:2793-2825. 2. Taylor KE, Stouffer RJ, Meehl GA (2011) An Overview of CMIP5 and the Experiment Design. Bull Am Meteorol Soc 93:485-498.

Emergence of new hydrologic regimes of surface water resources in the conterminous United States under future warming

NASA Astrophysics Data System (ADS)

Leng, Guoyong; Huang, Maoyi; Voisin, Nathalie; Zhang, Xuesong; Asrar, Ghassem R.; Leung, L. Ruby

2016-11-01

Despite the importance of surface water to people and ecosystems, few studies have explored detectable changes in surface water supply in a changing climate, given its large natural variability. Here we analyze runoff projections from the Variable Infiltration Capacity hydrological model driven by 97 downscaled and bias-corrected Coupled Model Intercomparison Project Phase 5 climate projections over the conterminous United States (CONUS). Our results show that more than 40% of the CONUS land area will experience significant changes in the probability distribution functions (i.e. PDFs) of summer and winter runoff by the end of the 21st century, which may pose great challenges to future surface water supply. Sub-basin mean runoff PDFs are projected to change significantly after 2040s depending on the emission scenarios, with earliest occurrence in the Pacific Northwest and northern California regions. When examining the response as a function of changes in the global mean temperature (ΔGMT), a linear relationship is revealed at the 95% confidence level. Generally, 1 °C increase of GMT leads to 11% and 17% more lands experiencing changes in summer and winter runoff PDFs, respectively. Such changes in land fraction scale with ΔGMT at the country scale independent of emission scenarios, but the same relationship does not necessarily hold at sub-basin scales, due to the larger role of atmospheric circulation changes and their uncertainties on regional precipitation. Further analyses show that the emergence of significant changes in sub-basin runoff PDFs is indicative of the emergence of new hydrology regimes and it is dominated by the changes in variability rather than shift in the mean, regardless of the emission scenarios.

MMAB Sea Ice Forecast Page

Science.gov Websites

verification statistics Grumbine, R. W., Virtual Floe Ice Drift Forecast Model Intercomparison, Weather and Forecasting, 13, 886-890, 1998. MMAB Note: Virtual Floe Ice Drift Forecast Model Intercomparison 1996 pdf ~47

Performance evaluation of elemental analysis/isotope ratio mass spectrometry methods for the determination of the D/H ratio in tetramethylurea and other compounds--results of a laboratory inter-comparison.

PubMed

Bréas, Olivier; Thomas, Freddy; Zeleny, Reinhard; Calderone, Giovanni; Jamin, Eric; Guillou, Claude

2007-01-01

Tetramethylurea (TMU) with a certified D/H ratio is the internal standard for Site-specific Natural Isotope Fractionation measured by Nuclear Magnetic Resonance (SNIF-NMR) analysis of wine ethanol for detection of possible adulterations (Commission Regulation 2676/90). A new batch of a TMU certified reference material (CRM) is currently being prepared. Whereas SNIF-NMR has been employed up to now, Elemental Analysis/Isotope Ratio Mass Spectrometry ((2)H-EA-IRMS) was envisaged as the method of choice for value assignment of the new CRM, as more precise (better repeatable) data might be obtained, resulting in lower uncertainty of the certified value. In order to evaluate the accuracy and intra- and inter-laboratory reproducibility of (2)H-EA-IRMS methods, a laboratory inter-comparison was carried out by analysing TMU and other organic compounds, as well as some waters. The results revealed that experienced laboratories are capable of generating robust and well comparable data, which highlights the emerging potential of IRMS in food authenticity testing. However, a systematic bias between IRMS and SNIF-NMR reference data was observed for TMU; this lack of data consistency rules out the (2)H-IRMS technique for the characterisation measurement of the new TMU CRM.

The Earth System Documentation (ES-DOC) project

NASA Astrophysics Data System (ADS)

Murphy, S.; Greenslade, M. A.; Treshansky, A.; DeLuca, C.; Guilyardi, E.; Denvil, S.

2013-12-01

Earth System Documentation (ES-DOC) is an international project supplying high quality tools and services in support of Earth system documentation creation, analysis and dissemination. It is nurturing a sustainable standards based documentation ecosystem that aims to become an integral part of the next generation of exa-scale dataset archives. ES-DOC leverages open source software, and applies a software development methodology that places end-user narratives at the heart of all it does. ES-DOC has initially focused upon nurturing the Earth System Model (ESM) documentation eco-system. Within this context ES-DOC leverages the emerging Common Information Model (CIM) metadata standard, which has supported the following projects: ** Coupled Model Inter-comparison Project Phase 5 (CMIP5); ** Dynamical Core Model Inter-comparison Project (DCMIP-2012); ** National Climate Predictions and Projections Platforms (NCPP) Quantitative Evaluation of Downscaling Workshop (QED-2013). This presentation will introduce the project to a wider audience and will demonstrate the current production level capabilities of the eco-system: ** An ESM documentation Viewer embeddable into any website; ** An ESM Questionnaire configurable on a project by project basis; ** An ESM comparison tool reusable across projects; ** An ESM visualization tool reusable across projects; ** A search engine for speedily accessing published documentation; ** Libraries for streamlining document creation, validation and publishing pipelines.

Climate change impacts on tree ranges: model intercomparison facilitates understanding and quantification of uncertainty.

PubMed

Cheaib, Alissar; Badeau, Vincent; Boe, Julien; Chuine, Isabelle; Delire, Christine; Dufrêne, Eric; François, Christophe; Gritti, Emmanuel S; Legay, Myriam; Pagé, Christian; Thuiller, Wilfried; Viovy, Nicolas; Leadley, Paul

2012-06-01

Model-based projections of shifts in tree species range due to climate change are becoming an important decision support tool for forest management. However, poorly evaluated sources of uncertainty require more scrutiny before relying heavily on models for decision-making. We evaluated uncertainty arising from differences in model formulations of tree response to climate change based on a rigorous intercomparison of projections of tree distributions in France. We compared eight models ranging from niche-based to process-based models. On average, models project large range contractions of temperate tree species in lowlands due to climate change. There was substantial disagreement between models for temperate broadleaf deciduous tree species, but differences in the capacity of models to account for rising CO(2) impacts explained much of the disagreement. There was good quantitative agreement among models concerning the range contractions for Scots pine. For the dominant Mediterranean tree species, Holm oak, all models foresee substantial range expansion. © 2012 Blackwell Publishing Ltd/CNRS.

A Practitioners Perspective on Verification

NASA Astrophysics Data System (ADS)

Steenburgh, R. A.

2017-12-01

NOAAs Space Weather Prediction Center offers a wide range of products and services to meet the needs of an equally wide range of customers. A robust verification program is essential to the informed use of model guidance and other tools by both forecasters and end users alike. In this talk, we present current SWPC practices and results, and examine emerging requirements and potential approaches to satisfy them. We explore the varying verification needs of forecasters and end users, as well as the role of subjective and objective verification. Finally, we describe a vehicle used in the meteorological community to unify approaches to model verification and facilitate intercomparison.

Intercomparison of a 'Bottom-up' and 'Top-down' Modeling Paradigm for estimating carbon and latent heat fluxes over a variety of vegetative regimes across the U.S., Agricultural and Forest Meteorology

USDA-ARS?s Scientific Manuscript database

Biophysical models intended for routine applications at a range of scales should attempt to balance the competing demands of generality and simplicity and be capable of realistically simulating the response of CO2 and energy fluxes to environmental and physiological forcings. At the same time they m...

NRC TLD Direct Radiation Monitoring Network. Volume 15, No. 4: Quarterly progress report, October--December 1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Struckmeyer, R.

This report presents the results of the NRC Direct Radiation Monitoring Network for the fourth quarter of 1995. It provides the ambient radiation levels measured in the vicinity of 75 sites throughout the United States. In addition, it describes the equipment used, monitoring station selection criteria, characterization of the dosimeter response, calibration procedures, statistical methods, intercomparison, and quality assurance program.

SIMBIOS Normalized Water-Leaving Radiance Calibration and Validation: Sensor Response, Atmospheric Corrections, Stray Light and Sun Glint. Chapter 14

NASA Technical Reports Server (NTRS)

Mueller, James L.

2001-01-01

This Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) contract supports acquisition of match up radiometric and bio-optical data for validation of Sea-Viewing Wide Field-of-view Sensor (SeaWiFS) and other ocean color satellites, and evaluation of uncertainty budgets and protocols for in situ measurements of normalized water leaving radiances.

Decadal shifts of East Asian summer monsoon in a climate model free of explicit GHGs and aerosols

NASA Astrophysics Data System (ADS)

Lin, Renping; Zhu, Jiang; Zheng, Fei

2016-12-01

The East Asian summer monsoon (EASM) experienced decadal transitions over the past few decades, and the associated "wetter-South-drier-North" shifts in rainfall patterns in China significantly affected the social and economic development in China. Two viewpoints stand out to explain these decadal shifts, regarding the shifts either a result of internal variability of climate system or that of external forcings (e.g. greenhouse gases (GHGs) and anthropogenic aerosols). However, most climate models, for example, the Atmospheric Model Intercomparison Project (AMIP)-type simulations and the Coupled Model Intercomparison Project (CMIP)-type simulations, fail to simulate the variation patterns, leaving the mechanisms responsible for these shifts still open to dispute. In this study, we conducted a successful simulation of these decadal transitions in a coupled model where we applied ocean data assimilation in the model free of explicit aerosols and GHGs forcing. The associated decadal shifts of the three-dimensional spatial structure in the 1990s, including the eastward retreat, the northward shift of the western Pacific subtropical high (WPSH), and the south-cool-north-warm pattern of the upper-level tropospheric temperature, were all well captured. Our simulation supports the argument that the variations of the oceanic fields are the dominant factor responsible for the EASM decadal transitions.

Decadal shifts of East Asian summer monsoon in a climate model free of explicit GHGs and aerosols

PubMed Central

Lin, Renping; Zhu, Jiang; Zheng, Fei

2016-01-01

The East Asian summer monsoon (EASM) experienced decadal transitions over the past few decades, and the associated "wetter-South-drier-North" shifts in rainfall patterns in China significantly affected the social and economic development in China. Two viewpoints stand out to explain these decadal shifts, regarding the shifts either a result of internal variability of climate system or that of external forcings (e.g. greenhouse gases (GHGs) and anthropogenic aerosols). However, most climate models, for example, the Atmospheric Model Intercomparison Project (AMIP)-type simulations and the Coupled Model Intercomparison Project (CMIP)-type simulations, fail to simulate the variation patterns, leaving the mechanisms responsible for these shifts still open to dispute. In this study, we conducted a successful simulation of these decadal transitions in a coupled model where we applied ocean data assimilation in the model free of explicit aerosols and GHGs forcing. The associated decadal shifts of the three-dimensional spatial structure in the 1990s, including the eastward retreat, the northward shift of the western Pacific subtropical high (WPSH), and the south-cool-north-warm pattern of the upper-level tropospheric temperature, were all well captured. Our simulation supports the argument that the variations of the oceanic fields are the dominant factor responsible for the EASM decadal transitions. PMID:27934933

International NMR-based Environmental Metabolomics Intercomparison Exercise

EPA Science Inventory

Several fundamental requirements must be met so that NMR-based metabolomics and the related technique of metabonomics can be formally adopted into environmental monitoring and chemical risk assessment. Here we report an intercomparison exercise which has evaluated the effectivene...

PM 2.5 ORGANIC SPECIATION INTERCOMPARISON RESULTS

EPA Science Inventory

This abstract describes a poster on results to a laboratory intercomparison of organic aerosol speciation analysis to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. T...

Total ozone measurement: Intercomparison of prototype New Zealand filter instrument and Dobson spectrophotometer

NASA Technical Reports Server (NTRS)

Basher, R. E.

1978-01-01

A five month intercomparison showed that the total ozone amounts of a prototype narrowband interference filter instrument were 7% less than those of a Dobson instrument for an ozone range of 0.300 to 0.500 atm cm and for airmasses less than two. The 7% bias was within the intercomparison calibration uncertainty. An airmass dependence in the Dobson instrument made the bias relationship airmass-dependent but the filter instrument's ozone values were generally constant to 2% up to an airmass of four. Long term drift in the bias was negligible.

The Inter-Sectoral Impact Model Intercomparison Project (ISI–MIP): Project framework

PubMed Central

Warszawski, Lila; Frieler, Katja; Huber, Veronika; Piontek, Franziska; Serdeczny, Olivia; Schewe, Jacob

2014-01-01

The Inter-Sectoral Impact Model Intercomparison Project offers a framework to compare climate impact projections in different sectors and at different scales. Consistent climate and socio-economic input data provide the basis for a cross-sectoral integration of impact projections. The project is designed to enable quantitative synthesis of climate change impacts at different levels of global warming. This report briefly outlines the objectives and framework of the first, fast-tracked phase of Inter-Sectoral Impact Model Intercomparison Project, based on global impact models, and provides an overview of the participating models, input data, and scenario set-up. PMID:24344316

Fabrication and characterization of optical super-smooth surfaces

NASA Astrophysics Data System (ADS)

Schmitt, Dirk-Roger; Kratz, Frank; Ringel, Gabriele A.; Mangelsdorf, Juergen; Creuzet, Francois; Garratt, John D.

1995-08-01

Intercomparison roughness measurements have been carried out at supersmooth artefacts fabricated from BK7, fused silica, and Zerodur. The surface parameters were determined using a special prototype of the mechanical profiler Nanostep (Rank Taylor Hobson), the Optical Heterodyne Profiler Z5500 (Zygo), and an Atomic Force Microscope (Park Scientific) with an improved acquisition technique. The intercomparison was performed after the range of collected spatial wavelength for each instrument was adjusted using digital filtering techniques. It is demonstrated for different roughness ranges that are applied superpolishing techniques yield supersmooth artefacts which can be used for more intercomparisons.

Water vapour inter-comparison effort in the framework of the hydrological cycle in the mediterranean experiment - special observation period (hymex-sop1)

NASA Astrophysics Data System (ADS)

Summa, Donato; Di Girolamo, Paolo; Flamant, Cyrille; De Rosa, Benedetto; Cacciani, Marco; Stelitano, Dario

2018-04-01

Accurate measurements of the vertical profiles of water vapour are of paramount importance for most key areas of atmospheric sciences. A comprehensive inter-comparison between different remote sensing and in-situ sensors has been carried out in the frame work of the first Special Observing Period of the Hydrological cycle in the Mediterranean Experiment for the purpose of obtaining accurate error estimates for these sensors. The inter-comparison involves a ground-based Raman lidar (BASIL), an airborne DIAL (LEANDRE2), a microwave radiometer, radiosondes and aircraft in-situ sensors.

Intercomparison of chemical mechanisms for air quality policy formulation and assessment under North American conditions.

PubMed

Derwent, Richard

2017-07-01

The intercomparison of seven chemical mechanisms for their suitability for air quality policy formulation and assessment is described. Box modeling techniques were employed using 44 sets of background environmental conditions covering North America to constrain the chemical development of the longer lived species. The selected mechanisms were modified to enable an unbiased assessment of the adequacy of the parameterizations of photochemical ozone production from volatile organic compound (VOC) oxidation in the presence of NO x . Photochemical ozone production rates responded differently to 30% NO x and VOC reductions with the different mechanisms, despite the striking similarities between the base-case ozone production rates. The 30% reductions in NO x and VOCs also produced changes in OH. The responses in OH to 30% reductions in NO x and VOCs appeared to be more sensitive to mechanism choice, compared with the responses in the photochemical ozone production rates. Although 30% NO x reductions generally led to decreases in OH, 30% reductions in VOCs led to increases in OH, irrespective of mechanism choice and background environmental conditions. The different mechanisms therefore gave different OH responses to NO x and VOC reductions and so would give different responses in terms of changes in the fate and behavior of air toxics, acidification and eutrophication, and fine particle formation compared with others, in response to ozone control strategies. Policymakers need to understand that there are likely to be inherent differences in the responses to ozone control strategies between different mechanisms, depending on background environmental conditions and the extents of NO x and VOC reductions under consideration. The purpose of this paper is to compare predicted ozone responses to NO x and VOC reductions with seven chemical mechanisms under North American conditions. The good agreement found between the tested mechanisms should provide some support for their application in the air quality models used for policymaking.

A new PUB-working group on SLope InterComparison Experiments (SLICE)

NASA Astrophysics Data System (ADS)

McGuire, K.; Retter, M.; Freer, J.; Troch, P.; McDonnell, J.

2006-05-01

The International Association of Hydrological Sciences (IAHS) decade on Prediction in Ungauged Basins (PUB) has the scientific goal to shift hydrology from calibration reliant models to new and rich understanding- based models. To support this, six PUB science themes have been developed under the PUB Science Steering group. Theme 1 covers basin inter-comparison and classification. The SLope InterComparison Experiment (SLICE) is a newly-formed working group aligned with theme 1. Its 2- year target is to promote the improved understanding of regional hydrological characteristics via hillslope inter- comparison studies and top-down analysis of data from hillslope experiments from around the world. It will further deliver the major building blocks of a catchment classification system. A first workshop of SLICE took place 26-28 September 2005 at the HJ Andrews Experimental Forest, Oregon, USA. 40 participants from seven countries were in attendance. The program consisted of keynote presentations on the state-of-the-art of hillslope hydrology, outlining a hillslope classification system, and through small group discussion, a focus on the following questions: a.) How can we capture flow path heterogeneity at the hillslope scale with residence time distributions? b.) Can networks help characterize hillslope subsurface systems? c.) What patterns are useful to characterize in a hillslope comparison context? d.) How does bedrock permeability condition hillslope response? e.) Can we actually observe pressure waves in the field and/or how likely are they to exist at the hillslope continuum scale? The poster presents an overview of the workshop outcomes and directions of future work.

The role of simulation chambers in the development of spectroscopic techniques: campaigns at EUPHORE

NASA Astrophysics Data System (ADS)

Ródenas, Milagros; Muñoz, Amalia; Euphore Team

2016-04-01

Simulation chambers represent a very useful tool for the study of chemical reactions and their products, but also to characterize instruments. The development of spectroscopic techniques throughout the last decades has benefited from tests and intercomparison exercises carried out in chambers. In fact, instruments can be exposed to various controlled atmospheric scenarios that account for different environmental conditions, eliminating the uncertainties associated to fluctuations of the air mass, which must be taken into account when extrapolating results to the real conditions. Hence, a given instrument can be characterized by assessing its precision, accuracy, detection limits, time response and potential interferences in the presence of other chemical compounds, aerosols, etc. This implies that the instrument can be calibrated and validated, which allows to enhance the features of the instrument. Moreover, chambers are also the scenario of intercomparison trials, permitting multiple instruments to sample from the same well-mixed air mass simultaneously. An overview of different campaigns to characterize and/or intercompare spectroscopic techniques that have taken place in simulation chambers will be given; in particular, those carried out at EUPHORE (two twin domes, 200 m3 each, Spain), where various intercomparison exercises have been deployed under the frame of European projects (e.g. TOXIC, FIONA, PSOA campaigns supported by EUROCHAMP-II). With the common aim of measuring given compounds (e.g. HONO, NO2, OH, glyoxal, m-glyoxal, etc), an important number of spectroscopic instruments and institutions have been involved in chamber experiments, having the chance to intercompare among them and also with other non-spectroscopic systems (e.g. monitors, cromatographs, etc) or model simulations.

The Carbon Dioxide Removal Model Intercomparison Project (CDRMIP): rationale and experimental protocol for CMIP6

NASA Astrophysics Data System (ADS)

Keller, David P.; Lenton, Andrew; Scott, Vivian; Vaughan, Naomi E.; Bauer, Nico; Ji, Duoying; Jones, Chris D.; Kravitz, Ben; Muri, Helene; Zickfeld, Kirsten

2018-03-01

The recent IPCC reports state that continued anthropogenic greenhouse gas emissions are changing the climate, threatening severe, pervasive and irreversible impacts. Slow progress in emissions reduction to mitigate climate change is resulting in increased attention to what is called geoengineering, climate engineering, or climate intervention - deliberate interventions to counter climate change that seek to either modify the Earth's radiation budget or remove greenhouse gases such as CO2 from the atmosphere. When focused on CO2, the latter of these categories is called carbon dioxide removal (CDR). Future emission scenarios that stay well below 2 °C, and all emission scenarios that do not exceed 1.5 °C warming by the year 2100, require some form of CDR. At present, there is little consensus on the climate impacts and atmospheric CO2 reduction efficacy of the different types of proposed CDR. To address this need, the Carbon Dioxide Removal Model Intercomparison Project (or CDRMIP) was initiated. This project brings together models of the Earth system in a common framework to explore the potential, impacts, and challenges of CDR. Here, we describe the first set of CDRMIP experiments, which are formally part of the 6th Coupled Model Intercomparison Project (CMIP6). These experiments are designed to address questions concerning CDR-induced climate reversibility, the response of the Earth system to direct atmospheric CO2 removal (direct air capture and storage), and the CDR potential and impacts of afforestation and reforestation, as well as ocean alkalinization.>

The Carbon Dioxide Removal Model Intercomparison Project (CDRMIP): rationale and experimental protocol for CMIP6

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keller, David P.; Lenton, Andrew; Scott, Vivian

The recent IPCC reports state that continued anthropogenic greenhouse gas emissions are changing the climate, threatening severe, pervasive and irreversible impacts. Slow progress in emissions reduction to mitigate climate change is resulting in increased attention to what is called geoengineering, climate engineering, or climate intervention – deliberate interventions to counter climate change that seek to either modify the Earth's radiation budget or remove greenhouse gases such as CO 2 from the atmosphere. When focused on CO 2, the latter of these categories is called carbon dioxide removal (CDR). Future emission scenarios that stay well below 2 °C, and all emissionmore » scenarios that do not exceed 1.5 °C warming by the year 2100, require some form of CDR. At present, there is little consensus on the climate impacts and atmospheric CO 2 reduction efficacy of the different types of proposed CDR. To address this need, the Carbon Dioxide Removal Model Intercomparison Project (or CDRMIP) was initiated. This project brings together models of the Earth system in a common framework to explore the potential, impacts, and challenges of CDR. Here, we describe the first set of CDRMIP experiments, which are formally part of the 6th Coupled Model Intercomparison Project (CMIP6). These experiments are designed to address questions concerning CDR-induced climate reversibility, the response of the Earth system to direct atmospheric CO 2 removal (direct air capture and storage), and the CDR potential and impacts of afforestation and reforestation, as well as ocean alkalinization.>« less

Intercomparison of retrospective radon detectors.

PubMed Central

Field, R W; Steck, D J; Parkhurst, M A; Mahaffey, J A; Alavanja, M C

1999-01-01

We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type. Preliminary comparisons of the models used to translate track rate densities to average long-term radon concentrations differ between the two studies. Further calibration of the retrospective detectors' models for interpretation of track rate density may allow the pooling of studies that use glass-based retrospective radon detectors to determine historic residential radon exposures. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:10545336

Intercomparison of retrospective radon detectors.

PubMed

Field, R W; Steck, D J; Parkhurst, M A; Mahaffey, J A; Alavanja, M C

1999-11-01

We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type. Preliminary comparisons of the models used to translate track rate densities to average long-term radon concentrations differ between the two studies. Further calibration of the retrospective detectors' models for interpretation of track rate density may allow the pooling of studies that use glass-based retrospective radon detectors to determine historic residential radon exposures.

INTERCOMPARISON STUDY OF ATMOSPHERIC MERCURY MODELS: 1. COMPARISON OF MODELS WITH SHORT-TERM MEASUREMENTS

EPA Science Inventory

Five regional scale models with a horizontal domain covering the European continent and its surrounding seas, one hemispheric and one global scale model participated in an atmospheric mercury modelling intercomparison study. Model-predicted concentrations in ambient air were comp...

Estimating near-road pollutant dispersion: a model inter-comparison

EPA Science Inventory

A model inter-comparison study to assess the abilities of steady-state Gaussian dispersion models to capture near-road pollutant dispersion has been carried out with four models (AERMOD, run with both the area-source and volume-source options to represent roadways, CALINE, versio...

International intercomparison of measuring instruments for radon/thoron gas and radon short-lived daughter products in the NRPI Prague.

PubMed

Jílek, K; Hýža, M; Kotík, L; Thomas, J; Tomášek, L

2014-07-01

During the 7th European Conference on Protection Against Radon at Home and at Work held in the autumn of 2013 in Prague, the second intercomparison of measuring instruments for radon and its short-lived decay products and the first intercomparison of radon/thoron gas discriminative passive detectors in mix field of radon/thoron were organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI) in Prague. In total, 14 laboratories from 11 different countries took part in the 2013 NRPI intercomparison. They submitted both continuous monitors for the measurement of radon gas and equivalent equilibrium radon concentration in a big NRPI chamber (48 m3) and sets of passive detectors including radon/thoron discriminative for the measurement of radon gas in the big chamber and thoron gas in a small thoron chamber (150 dm3). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An intercomparison of carbon monoxide, nitric oxide, and hydroxyl measurement techniques - Overview of results

NASA Technical Reports Server (NTRS)

Hoell, J. M.; Gregory, G. L.; Carroll, M. A.; Mcfarland, M.; Ridley, B. A.; Davis, D. D.; Bradshaw, J.; Rodgers, M. O.; Torres, A. L.; Condon, E. P.

1984-01-01

Results from an intercomparison of methods to measure carbon monoxide (CO), nitric oxide (NO), and the hydroxyl radical (OH) are discussed. The intercomparison was conducted at Wallops Island, Virginia, in July 1983 and included a laser differential absorption and three grab sample/gas chromatograph methods for CO, a laser-induced fluorescence (LIF) and two chemiluminescence methods for NO, and two LIF methods and a radiocarbon tracer method for OH. The intercomparison was conducted as a field measurement program involving ambient measurements of CO (150-300 ppbv) and NO (10-180 pptv) from a common manifold with controlled injection of CO in incremental steps from 20 to 500 ppbv and NO in steps from 10 to 220 pptv. Only ambient measurements of OH were made. The agreement between the techniques was on the order of 14 percent for CO and 17 percent for NO. Hardware difficulties during the OH tests resulted in a data base with insufficient data and uncertanties too large to permit a meaningful intercomposition.

Operational overview of the NASA GTE/CITE 3 airborne instrument intercomparisons for sulfur dioxide, hydrogen sulfide, carbonyl sulfide, dimethyl sulfide, and carbon disulfide

NASA Technical Reports Server (NTRS)

Hoell, James M., Jr.; Davis, Douglas D.; Gregory, Gerald L.; Mcneal, Robert J.; Bendura, Richard J.; Drewry, Joseph W.; Barrick, John D.; Kirchhoff, Volker W. J. H.; Motta, Adauto G.; Navarro, Roger L.

1993-01-01

This paper reports the overall experimental design and gives a brief overview of results from the third airborne Chemical Instrumentation Test and Evaluation (CITE 3) mission conducted as part of the National Aeronautics and Space Administration's Global Tropospheric Experiment. The primary objective of CITE 3 was to evaluate the capability of instrumentation for airborne measurements of ambient concentrations of SO2, H2S, CS, dimethyl sulfide, and carbonyl sulfide. Ancillary measurements augmented the intercomparison data in order to address the secondary objective of CITE 3 which was to address specific issues related to the budget and photochemistry of tropospheric sulfur species. The CITE 3 mission was conducted on NASA's Wallops Flight Center Electra aircraft and included a ground-based intercomparison of sulfur standards and intercomparison/sulfur science flights conducted from the NASA Wallops Flight Facility, Wallops Island, Virginia, followed by flights from Natal, Brazil. Including the transit flights, CITE 3 included 16 flights encompassing approximately 96 flight hours.

A soil sampling intercomparison exercise for the ALMERA network.

PubMed

Belli, Maria; de Zorzi, Paolo; Sansone, Umberto; Shakhashiro, Abduhlghani; Gondin da Fonseca, Adelaide; Trinkl, Alexander; Benesch, Thomas

2009-11-01

Soil sampling and analysis for radionuclides after an accidental or routine release is a key factor for the dose calculation to members of the public, and for the establishment of possible countermeasures. The IAEA organized for selected laboratories of the ALMERA (Analytical Laboratories for the Measurement of Environmental Radioactivity) network a Soil Sampling Intercomparison Exercise (IAEA/SIE/01) with the objective of comparing soil sampling procedures used by different laboratories. The ALMERA network is a world-wide network of analytical laboratories located in IAEA member states capable of providing reliable and timely analysis of environmental samples in the event of an accidental or intentional release of radioactivity. Ten ALMERA laboratories were selected to participate in the sampling exercise. The soil sampling intercomparison exercise took place in November 2005 in an agricultural area qualified as a "reference site", aimed at assessing the uncertainties associated with soil sampling in agricultural, semi-natural, urban and contaminated environments and suitable for performing sampling intercomparison. In this paper, the laboratories sampling performance were evaluated.

Climate model simulations of the mid-Pliocene: Earth's last great interval of global warmth

USGS Publications Warehouse

Dolan, A.M.; Haywood, A.M.; Dowsett, H.J.

2012-01-01

Pliocene Model Intercomparison Project Workshop; Reston, Virginia, 2–4 August 2011 The Pliocene Model Intercomparison Project (PlioMIP), supported by the U.S. Geological Survey's (USGS) Pliocene Research, Interpretation and Synoptic Mapping (PRISM) project and Powell Center, is an integral part of a third iteration of the Paleoclimate Modelling Intercomparison Project (PMIP3). PlioMIP's aim is to systematically compare structurally different climate models. This is done in the context of the mid-Pliocene (~3.3–3.0 million years ago), a geological interval when the global annual mean temperature was similar to predictions for the next century.

Radon intercomparisons at EML, January 1983 and February 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisenne, I.M.; George, A.C.; Keller, H.W.

1985-02-01

This report summarizes the results of two radon measurement intercomparison exercises held at the Environmental Measurements Laboratory (EML) in January 1983 and February 1984. Nineteen organizations, including five US federal facilities, one national laboratory, two state laboratories, six universities, three private sector laboratories and two non-US facilities participated in these exercises. The results indicate good agreement among the participants at /sup 222/Rn concentration levels of 50 and 80 pCi.L/sup -1/. Improvements in the EML calibration facilities, and the participation of two US laboratories in a Nuclear Energy Agency intercomparison program are also discussed. 8 references, 6 figures, 8 tables.

ARM/GCSS/SPARC TWP-ICE CRM Intercomparison Study

NASA Technical Reports Server (NTRS)

Fridlind, Ann; Ackerman, Andrew; Petch, Jon; Field, Paul; Hill, Adrian; McFarquhar, Greg; Xie, Shaocheng; Zhang, Minghua

2010-01-01

Specifications are provided for running a cloud-resolving model (CRM) and submitting results in a standardized format for inclusion in a n intercomparison study and archiving for public access. The simulated case study is based on measurements obtained during the 2006 Tropical Warm Pool - International Cloud Experiment (TWP-ICE) led by the U. S. department of Energy Atmospheric Radiation Measurement (ARM) program. The modeling intercomparison study is based on objectives developed in concert with the Stratospheric Processes And their Role in Climate (SPARC) program and the GEWEX cloud system study (GCSS) program. The Global Energy and Water Cycle Experiment (GEWEX) is a core project of the World Climate Research PRogramme (WCRP).

RAMI4PILPS: An intercomparison of formulations for the partitioning of solar radiation in land surface models

NASA Astrophysics Data System (ADS)

Widlowski, J.-L.; Pinty, B.; Clerici, M.; Dai, Y.; de Kauwe, M.; De Ridder, K.; Kallel, A.; Kobayashi, H.; Lavergne, T.; Ni-Meister, W.; Olchev, A.; Quaife, T.; Wang, S.; Yang, W.; Yang, Y.; Yuan, H.

2011-06-01

Remotely sensed, multiannual data sets of shortwave radiative surface fluxes are now available for assimilation into land surface schemes (LSSs) of climate and/or numerical weather prediction models. The RAMI4PILPS suite of virtual experiments assesses the accuracy and consistency of the radiative transfer formulations that provide the magnitudes of absorbed, reflected, and transmitted shortwave radiative fluxes in LSSs. RAMI4PILPS evaluates models under perfectly controlled experimental conditions in order to eliminate uncertainties arising from an incomplete or erroneous knowledge of the structural, spectral and illumination related canopy characteristics typical for model comparison with in situ observations. More specifically, the shortwave radiation is separated into a visible and near-infrared spectral region, and the quality of the simulated radiative fluxes is evaluated by direct comparison with a 3-D Monte Carlo reference model identified during the third phase of the Radiation transfer Model Intercomparison (RAMI) exercise. The RAMI4PILPS setup thus allows to focus in particular on the numerical accuracy of shortwave radiative transfer formulations and to pinpoint to areas where future model improvements should concentrate. The impact of increasing degrees of structural and spectral subgrid variability on the simulated fluxes is documented and the relevance of any thus emerging biases with respect to gross primary production estimates and shortwave radiative forcings due to snow and fire events are investigated.

THE NORTH AMERICAN MERCURY MODEL INTER-COMPARISON STUDY (NAMMIS)

EPA Science Inventory

This paper describes the North American Mercury Model Inter-comparison Study (NAMMIS). The NAMMIS is an effort to apply atmospheric Hg models in a tightly constrained testing environment with a focus on North America. With each model using the same input data sets for initial co...

Geometric state space uncertainty as a new type of uncertainty addressing disparity in ';emergent properties' between real and modeled systems

NASA Astrophysics Data System (ADS)

Montero, J. T.; Lintz, H. E.; Sharp, D.

2013-12-01

Do emergent properties that result from models of complex systems match emergent properties from real systems? This question targets a type of uncertainty that we argue requires more attention in system modeling and validation efforts. We define an ';emergent property' to be an attribute or behavior of a modeled or real system that can be surprising or unpredictable and result from complex interactions among the components of a system. For example, thresholds are common across diverse systems and scales and can represent emergent system behavior that is difficult to predict. Thresholds or other types of emergent system behavior can be characterized by their geometry in state space (where state space is the space containing the set of all states of a dynamic system). One way to expedite our growing mechanistic understanding of how emergent properties emerge from complex systems is to compare the geometry of surfaces in state space between real and modeled systems. Here, we present an index (threshold strength) that can quantify a geometric attribute of a surface in state space. We operationally define threshold strength as how strongly a surface in state space resembles a step or an abrupt transition between two system states. First, we validated the index for application in greater than three dimensions of state space using simulated data. Then, we demonstrated application of the index in measuring geometric state space uncertainty between a real system and a deterministic, modeled system. In particular, we looked at geometric space uncertainty between climate behavior in 20th century and modeled climate behavior simulated by global climate models (GCMs) in the Coupled Model Intercomparison Project phase 5 (CMIP5). Surfaces from the climate models came from running the models over the same domain as the real data. We also created response surfaces from a real, climate data based on an empirical model that produces a geometric surface of predicted values in state space. We used a kernel regression method designed to capture the geometry of real data pattern without imposing shape assumptions a priori on the data; this kernel regression method is known as Non-parametric Multiplicative Regression (NPMR). We found that quantifying and comparing a geometric attribute in more than three dimensions of state space can discern whether the emergent nature of complex interactions in modeled systems matches that of real systems. Further, this method has potentially wider application in contexts where searching for abrupt change or ';action' in any hyperspace is desired.

PNNL Results from 2010 CALIBAN Criticality Accident Dosimeter Intercomparison Exercise

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hill, Robin L.; Conrady, Matthew M.

2011-10-28

This document reports the results of the Hanford personnel nuclear accident dosimeter (PNAD) and fixed nuclear accident dosimeter (FNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on September 20-23, 2010. Pacific Northwest National Laboratory (PNNL) participated in a criticality accident dosimeter intercomparison exercise at the Commissariat a Energie Atomique (CEA) Valduc Center near Dijon, France on September 20-23, 2010. The intercomparison exercise was funded by the U.S. Department of Energy, Nuclear Criticality Safety Program, with Lawrence Livermore National Laboratory as the lead Laboratory. PNNL was one of six invited DOE Laboratory participants. The other participatingmore » Laboratories were: Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Savannah River Site (SRS), the Y-12 National Security Complex at Oak Ridge, and Sandia National Laboratory (SNL). The goals of PNNL's participation in the intercomparison exercise were to test and validate the procedures and algorithm currently used for the Hanford personnel nuclear accident dosimeters (PNADs) on the metallic reactor, CALIBAN, to test exposures to PNADs from the side and from behind a phantom, and to test PNADs that were taken from a historical batch of Hanford PNADs that had varying degrees of degradation of the bare indium foil. Similar testing of the PNADs was done on the Valduc SILENE test reactor in 2009 (Hill and Conrady, 2010). The CALIBAN results are reported here.« less

Composite Study Of Aerosol Long-Range Transport Events From East Asia And North America

NASA Astrophysics Data System (ADS)

Jiang, X.; Waliser, D. E.; Guan, B.; Xavier, P.; Petch, J.; Klingaman, N. P.; Woolnough, S.

2011-12-01

While the Madden-Julian Oscillation (MJO) exerts pronounced influences on global climate and weather systems, current general circulation models (GCMs) exhibit rather limited capability in representing this prominent tropical variability mode. Meanwhile, the fundamental physics of the MJO are still elusive. Given the central role of the diabatic heating for prevailing MJO theories and demands for reducing the model deficiencies in simulating the MJO, a global model inter-comparison project on diabatic processes and vertical heating structure associated with the MJO has been coordinated through a joint effort by the WCRP-WWRP/THORPEX YOTC MJO Task Force and GEWEX GASS Program. In this presentation, progress of this model inter-comparison project will be reported, with main focus on climate simulations from about 27 atmosphere-only and coupled GCMs. Vertical structures of heating and diabatic processes associated with the MJO based on multi-model simulations will be presented along with their reanalysis and satellite estimate counterparts. Key processes possibly responsible for a realistic simulation of the MJO, including moisture-convection interaction, gross moist stability, ocean coupling, and surface heat flux, will be discussed.

Representation of the Great Lakes in the Coupled Model Intercomparison Project Version 5

NASA Astrophysics Data System (ADS)

Briley, L.; Rood, R. B.

2017-12-01

The U.S. Great Lakes play a significant role in modifying regional temperatures and precipitation, and as the lakes change in response to a warming climate (i.e., warmer surface water temperatures, decreased ice cover, etc) lake-land-atmosphere dynamics are affected. Because the lakes modify regional weather and are a driver of regional climate change, understanding how they are represented in climate models is important to the reliability of model based information for the region. As part of the Great Lakes Integrated Sciences + Assessments (GLISA) Ensemble project, a major effort is underway to evaluate the Coupled Model Intercomparison Project version (CMIP) 5 global climate models for how well they physically represent the Great Lakes and lake-effects. The CMIP models were chosen because they are a primary source of information in many products developed for decision making (i.e., National Climate Assessment, downscaled future climate projections, etc.), yet there is very little description of how well they represent the lakes. This presentation will describe the results of our investigation of if and how the Great Lakes are represented in the CMIP5 models.

Intercomparison of model response and internal variability across climate model ensembles

NASA Astrophysics Data System (ADS)

Kumar, Devashish; Ganguly, Auroop R.

2017-10-01

Characterization of climate uncertainty at regional scales over near-term planning horizons (0-30 years) is crucial for climate adaptation. Climate internal variability (CIV) dominates climate uncertainty over decadal prediction horizons at stakeholders' scales (regional to local). In the literature, CIV has been characterized indirectly using projections of climate change from multi-model ensembles (MME) instead of directly using projections from multiple initial condition ensembles (MICE), primarily because adequate number of initial condition (IC) runs were not available for any climate model. Nevertheless, the recent availability of significant number of IC runs from one climate model allows for the first time to characterize CIV directly from climate model projections and perform a sensitivity analysis to study the dominance of CIV compared to model response variability (MRV). Here, we measure relative agreement (a dimensionless number with values ranging between 0 and 1, inclusive; a high value indicates less variability and vice versa) among MME and MICE and find that CIV is lower than MRV for all projection time horizons and spatial resolutions for precipitation and temperature. However, CIV exhibits greater dominance over MRV for seasonal and annual mean precipitation at higher latitudes where signals of climate change are expected to emerge sooner. Furthermore, precipitation exhibits large uncertainties and a rapid decline in relative agreement from global to continental, regional, or local scales for MICE compared to MME. The fractional contribution of uncertainty due to CIV is invariant for precipitation and decreases for temperature as lead time progresses towards the end of the century.

SimilarityExplorer: A visual inter-comparison tool for multifaceted climate data

Treesearch

J. Poco; A. Dasgupta; Y. Wei; W. Hargrove; C. Schwalm; R. Cook; E. Bertini; C. Silva

2014-01-01

Inter-comparison and similarity analysis to gauge consensus among multiple simulation models is a critical visualization problem for understanding climate change patterns. Climate models, specifically, Terrestrial Biosphere Models (TBM) represent time and space variable ecosystem processes, for example, simulations of photosynthesis and respiration, using algorithms...

FIELD INTERCOMPARISON OF SULFATE DRY DEPOSITION MONITORING AND MEASUREMENT METHODS: PRELIMINARY RESULTS

EPA Science Inventory

The Illinois State Water Survey hosted a three-week field intercomparison of several sulfate dry deposition measurement techniques during September 81. The site was an 80-acre grass field in a rural area 14 km southwest of Champaign, IL. The vegetation consisted of mixed grasses ...

An Analysis of Simulated Wet Deposition of Mercury from the North American Mercury Model Intercomparison Study

EPA Science Inventory

A previous intercomparison of atmospheric mercury models in North America has been extended to compare simulated and observed wet deposition of mercury. Three regional-scale atmospheric mercury models were tested; CMAQ, REMSAD and TEAM. These models were each employed using thr...

METHODS INTERCOMPARISON OF SAMPLERS FOR EPA'S NATIONAL PM 2.5 CHEMICAL SPECIATION NETWORK

EPA Science Inventory

The objective of this sampler intercomparison field study is to determine the performance characteristics for the collection of the chemical components of PM2.5 by the chemical speciation monitors developed for the national PM2.5 network relative to each other, to the Federal R...

Solid precipitation measurement intercomparison in Bismarck, North Dakota, from 1988 through 1997

USGS Publications Warehouse

Ryberg, Karen R.; Emerson, Douglas G.; Macek-Rowland, Kathleen M.

2009-01-01

A solid precipitation measurement intercomparison was recommended by the World Meteorological Organization (WMO) and was initiated after approval by the ninth session of the Commission for Instruments and Methods of Observation. The goal of the intercomparison was to assess national methods of measuring solid precipitation against methods whose accuracy and reliability were known. A field study was started in Bismarck, N. Dak., during the 1988-89 winter as part of the intercomparison. The last official field season of the WMO intercomparison was 1992-93; however, the Bismarck site continued to operate through the winter of 1996-97. Precipitation events at Bismarck were categorized as snow, mixed, or rain on the basis of descriptive notes recorded as part of the solid precipitation intercomparison. The rain events were not further analyzed in this study. Catch ratios (CRs) - the ratio of the precipitation catch at each gage to the true precipitation measurement (the corrected double fence intercomparison reference) - were calculated. Then, regression analysis was used to develop equations that model the snow and mixed precipitation CRs at each gage as functions of wind speed and temperature. Wind speed at the gages, functions of temperature, and upper air conditions (wind speed and air temperature at 700 millibars pressure) were used as possible explanatory variables in the multiple regression analysis done for this study. The CRs were modeled by using multiple regression analysis for the Tretyakov gage, national shielded gage, national unshielded gage, AeroChem gage, national gage with double fence, and national gage with Wyoming windshield. As in earlier studies by the WMO, wind speed and air temperature were found to influence the CR of the Tretyakov gage. However, in this study, the temperature variable represented the average upper air temperature over the duration of the event. The WMO did not use upper air conditions in its analysis. The national shielded and unshielded gages where found to be influenced by functions of wind speed only, as in other studies, but the upper air wind speed was used as an explanatory variable in this study. The AeroChem gage was not used in the WMO intercomparison study for 1987-93. The AeroChem gage had a highly varied CR at Bismarck, and a number of variables related to wind speed and temperature were used in the model for the CR. Despite extensive efforts to find a model for the national gage with double fence, no statistically significant regression model was found at the 0.05 level of statistical significance. The national gage with Wyoming windshield had a CR modeled by temperature and wind speed variables, and the regression relation had the highest coefficient of determination (R2 = 0.572) and adjusted coefficient of multiple determination (R2a = 0.476) of all of the models identified for any gage. Three of the gage CRs evaluated could be compared with those in the WMO intercomparison study for 1987-93. The WMO intercomparison had the advantage of a much larger dataset than this study. However, the data in this study represented a longer time period. Snow precipitation catch is highly varied depending on the equipment used and the weather conditions. Much of the variation is not accounted for in the WMO equations or in the equations developed in this study, particularly for unshielded gages. Extensive attempts at regression analysis were made with the mixed precipitation data, but it was concluded that the sample sizes were not large enough to model the CRs. However, the data could be used to test the WMO intercomparison equations. The mixed precipitation equations for the Tretyakov and national shielded gages are similar to those for snow in that they are more likely to underestimate precipitation when observed amounts were small and overestimate precipitation when observed amounts were relatively large. Mixed precipitation is underestimated by the WMO adjustment and t

Constraining the low-cloud optical depth feedback at middle and high latitudes using satellite observations

DOE PAGES

Terai, C. R.; Klein, S. A.; Zelinka, M. D.

2016-08-26

The increase in cloud optical depth with warming at middle and high latitudes is a robust cloud feedback response found across all climate models. This study builds on results that suggest the optical depth response to temperature is timescale invariant for low-level clouds. The timescale invariance allows one to use satellite observations to constrain the models' optical depth feedbacks. Three passive-sensor satellite retrievals are compared against simulations from eight models from the Atmosphere Model Intercomparison Project (AMIP) of the 5th Coupled Model Intercomparison Project (CMIP5). This study confirms that the low-cloud optical depth response is timescale invariant in the AMIPmore » simulations, generally at latitudes higher than 40°. Compared to satellite estimates, most models overestimate the increase in optical depth with warming at the monthly and interannual timescales. Many models also do not capture the increase in optical depth with estimated inversion strength that is found in all three satellite observations and in previous studies. The discrepancy between models and satellites exists in both hemispheres and in most months of the year. A simple replacement of the models' optical depth sensitivities with the satellites' sensitivities reduces the negative shortwave cloud feedback by at least 50% in the 40°–70°S latitude band and by at least 65% in the 40°–70°N latitude band. Furthermore, based on this analysis of satellite observations, we conclude that the low-cloud optical depth feedback at middle and high latitudes is likely too negative in climate models.« less

Constraining the low-cloud optical depth feedback at middle and high latitudes using satellite observations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terai, C. R.; Klein, S. A.; Zelinka, M. D.

The increase in cloud optical depth with warming at middle and high latitudes is a robust cloud feedback response found across all climate models. This study builds on results that suggest the optical depth response to temperature is timescale invariant for low-level clouds. The timescale invariance allows one to use satellite observations to constrain the models' optical depth feedbacks. Three passive-sensor satellite retrievals are compared against simulations from eight models from the Atmosphere Model Intercomparison Project (AMIP) of the 5th Coupled Model Intercomparison Project (CMIP5). This study confirms that the low-cloud optical depth response is timescale invariant in the AMIPmore » simulations, generally at latitudes higher than 40°. Compared to satellite estimates, most models overestimate the increase in optical depth with warming at the monthly and interannual timescales. Many models also do not capture the increase in optical depth with estimated inversion strength that is found in all three satellite observations and in previous studies. The discrepancy between models and satellites exists in both hemispheres and in most months of the year. A simple replacement of the models' optical depth sensitivities with the satellites' sensitivities reduces the negative shortwave cloud feedback by at least 50% in the 40°–70°S latitude band and by at least 65% in the 40°–70°N latitude band. Furthermore, based on this analysis of satellite observations, we conclude that the low-cloud optical depth feedback at middle and high latitudes is likely too negative in climate models.« less

Midlatitude Summer Drying: An Underestimated Threat in CMIP5 Models?

NASA Astrophysics Data System (ADS)

Douville, H.; Plazzotta, M.

2017-10-01

Early assessments of the hydrological impacts of global warming suggested both an intensification of the global water cycle and an expansion of dry areas. Yet these alarming conclusions were challenged by a number of latter studies emphasizing the lack of evidence in observations and historical simulations, as well as the large uncertainties in climate projections from the fifth phase of the Coupled Model Intercomparison Project (CMIP5). Here several aridity indices and a two-tier attribution strategy are used to demonstrate that a summer midlatitude drying has recently emerged over the northern continents, which is mainly attributable to anthropogenic climate change. This emerging signal is shown to be the harbinger of a long-term drying in the CMIP5 projections. Linear trends in the observed aridity indices can therefore be used as observational constraints and suggest that the projected midlatitude summer drying was underestimated by most CMIP5 models. Mitigating global warming therefore remains a priority to avoid dangerous impacts on global water and food security.

The Fifth Calibration/Data Product Validation Panel Meeting

NASA Technical Reports Server (NTRS)

1992-01-01

The minutes and associated documents prepared from presentations and meetings at the Fifth Calibration/Data Product Validation Panel meeting in Boulder, Colorado, April 8 - 10, 1992, are presented. Key issues include (1) statistical characterization of data sets: finding statistics that characterize key attributes of the data sets, and defining ways to characterize the comparisons among data sets; (2) selection of specific intercomparison exercises: selecting characteristic spatial and temporal regions for intercomparisons, and impact of validation exercises on the logistics of current and planned field campaigns and model runs; and (3) preparation of data sets for intercomparisons: characterization of assumptions, transportable data formats, labeling data files, content of data sets, and data storage and distribution (EOSDIS interface).

WE-D-17A-05: Measurement of Stray Radiation Within An Active Scanning Proton Therapy Facility: EURADOS WG9 Intercomparison Exercise of Active Dosimetry Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farah, J; Trompier, F; Stolarczyk, L

2014-06-15

Purpose: Intercomparison of active dosemeters in the measurement of stray radiation at the Trento active-scanning proton therapy facility. Methods: EURADOS WG9 carried out a large intercomparison exercise to test different dosemeters while measuring secondary neutrons within a 230 MeV scanned proton therapy facility. Detectors included two Bonner Sphere Spectrometers (BSS), three tissue equivalent proportional counters (TEPCHawk) and six rem-counters (Wendi II, Berthold, RadEye, a regular and an extended-range Anderson and Braun NM2B counters). Measurements of neutron ambient dose equivalents, H*(10), were done at several positions inside (8 positions) and outside (3 positions) the treatment room while irradiating a water tankmore » phantom with a 10 × 10 × 10 cc field. Results: A generally good agreement on H*(10) values was observed for the tested detectors. At distance of 2.25 m and angles 45°, 90° and 180° with respect to the beam axis, BSS and proportional counters agreed within 30%. Higher differences (up to 60%) were observed at the closest and farthest distances, i.e. at positions where detectors sensitivity, energy, fluence and angular response are highly dependent on neutron spectra (flux and energy). The highest neutron H*(10) value, ∼60 microSv/Gy, was measured at 1.15 m along the beam axis. H*(10) decreased significantly with the distance from the isocenter dropping to 1.1 microSv/Gy at 4.25 m and 90° from beam axis, ∼2 nanoSv/Gy at the entrance of the maze, 0.2 nanoSv/Gy at the door outside the room and below detection limit in the gantry control room and at an adjacent room. These values remain considerately lower than those of passively scattered proton beams. BSS and Hawk unfolded spectra provide valuable inputs when studying the response of each detector. Conclusion: TEPCs and BSS enable accurate measurements of stray neutrons while other rem-meters also give satisfactory results but require further improvements to reduce uncertainties.« less

INTERCOMPARISON STUDY OF ATMOSPHERIC MERCURY MODELS: 2. MODELING RESULTS VS. LONG-TERM OBSERVATIONS AND COMPARISON OF COUNTRY ATMOSPHERIC BALANCES

EPA Science Inventory

Five regional scale models with a horizontal domain covering the European continent and its surrounding seas, two hemispheric and one global scale model participated in the atmospheric Hg modelling intercomparison study. The models were compared between each other and with availa...

A Compendium on the NIST Radionuclidic Assays of the Massic Activity of 63Ni and 55Fe Solutions Used for an International Intercomparison of Liquid Scintillation Spectrometry Techniques

PubMed Central

Collé, R.; Zimmerman, B. E.

1997-01-01

The National Institute of Standards and Technology recently participated in an international measurement intercomparison for 63Ni and 55Fe, which was conducted amongst principal national radionuclidic metrology laboratories. The intercomparison was sponsored by EUROMET, and was primarily intended to evaluate the capabilities of liquid scintillation (LS) spectrometry techniques for standardizing nuclides that decay by low-energy β-emission (like 63Ni) and by low-Z (atomic number) electron capture (like 55Fe). The intercomparison findings exhibit a very good agreement for 63Ni amongst the various participating laboratories, including that for NIST, which suggests that the presently invoked LS methodologies are very capable of providing internationally-compatible standardizations for low-energy β-emitters. The results for 55Fe are in considerably poorer agreement, and demonstrated the existence of several unresolved problems. It has thus become apparent that there is a need for the various international laboratories to conduct rigorous, systematic evaluations of their LS capabilities in assaying radionuclides that decay by low-Z electron capture. PMID:27805141

SECOND LATIN AMERICAN INTERCOMPARISON ON INTERNAL DOSE ASSESSMENT.

PubMed

Rojo, A; Puerta, N; Gossio, S; Gómez Parada, I; Cruz Suarez, R; López, E; Medina, C; Lastra Boylan, J; Pinheiro Ramos, M; Mora Ramírez, E; Alves Dos Reis, A; Yánez, H; Rubio, J; Vironneau Janicek, L; Somarriba Vanegas, F; Puerta Ortiz, J; Salas Ramírez, M; López Bejerano, G; da Silva, T; Miri Oliveira, C; Terán, M; Alfaro, M; García, T; Angeles, A; Duré Romero, E; Farias de Lima, F

2016-09-01

Internal dosimetry intercomparisons are essential for the verification of applied models and the consistency of results'. To that aim, the First Regional Intercomparison was organised in 2005, and that results led to the Second Regional Intercomparison Exercise in 2013, which was organised in the frame of the RLA 9/066 and coordinated by Autoridad Regulatoria Nuclear of Argentina. Four simulated cases covering intakes of (131)I, (137)Cs and Tritium were proposed. Ninteen centres from thirteen different countries participated in this exercise. This paper analyses the participants' results in this second exercise in order to test their skills and acquired knowledge, particularly in the application of the IDEAS Guidelines. It is important to highlight the increased number of countries that participated in this exercise compared with the first one and, furthermore, the improvement in the overall performance. The impact of the International Atomic Energy Agency (IAEA) Projects since 2003 has led to a significant enhancement of internal dosimetry capabilities that strengthen the radiation protection of workers. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Landsat 8 Remote Sensing Reflectance (Rrs) Products: Evaluations, Intercomparisons, and Enhancements

NASA Technical Reports Server (NTRS)

Pahlevan, Nima; Schott, John R.; Franz, Bryan A.; Zibordi, Giuseppe; Markham, Brian; Bailey, Sean; Schaaf, Crystal B.; Ondrusek, Michael; Greb, Steven; Strait, Christopher M.

2017-01-01

The Operational Land Imager (OLI) onboard Landsat-8 is generating high-quality aquatic science products, the most critical of which is the remote sensing reflectance (Rrs), defined as the ratio of water-leaving radiance to the total downwelling irradiance just above water. The quality of the Rrs products has not, however, been extensively assessed. This manuscript provides a comprehensive evaluation of Level-1B, i.e., top of atmosphere reflectance, and Rrs products available from OLI imagery under near-ideal atmospheric conditions in moderately turbid waters. The procedure includes a) evaluations of the Rrs products at sites included in the Ocean Color component of the Aerosol Robotic Network (AERONET-OC), b) intercomparisons and cross-calibrations against other ocean color products, and c) optimizations of vicarious calibration gains across the entire OLI observing swath. Results indicate that the near-infrared and shortwave infrared (NIR-SWIR) band combinations yield the most robust and stable Rrs retrievals in moderately turbid waters. Intercomparisons against products derived from the Visible Infrared Imaging Radiometer Suite (VIIRS) and the Moderate Resolution Imaging Spectroradiometer onboard the Aqua platform (MODISA) indicate slight across-track non-uniformities (<1%) associated with OLI scenes in the blue bands. In both product domains (TOA and Rrs), on average, the OLI products were found larger in radiometric responses in the blue channels. Following the implementation of updated vicarious calibration gains and accounting for across-track non-uniformities, matchup analyses using independent in-situ validation data confirmed improvements in Rrs products. These findings further support high-fidelity OLI-derived aquatic science products in terms of both demonstrating a robust atmospheric correction method and providing consistent products across OLI's imaging swath.

Fast and Slow Precipitation Responses to Individual Climate Forcers: A PDRMIP Multimodel Study

NASA Technical Reports Server (NTRS)

Samset, B. H.; Myhre, G.; Forster, P.M.; Hodnebrog, O.; Andrews, T.; Faluvegi, G.; Flaschner, D.; Kasoar, M.; Kharin, V.; Kirkevag, A.;

Reproducibility in cyclostratigraphy: initiating an intercomparison project

NASA Astrophysics Data System (ADS)

Sinnesael, Matthias; De Vleeschouwer, David; Zeeden, Christian; Claeys, Philippe

2017-04-01

The study of astronomical climate forcing and the application of cyclostratigraphy have experienced a spectacular growth over the last decades. In the field of cyclostratigraphy a broad range in methodological approaches exist. However, comparative study between the different approaches is lacking. Different cases demand different approaches, but with the growing importance of the field, questions arise about reproducibility, uncertainties and standardization of results. The radioisotopic dating community, in particular, has done far-reaching efforts to improve reproducibility and intercomparison of radioisotopic dates and their errors. To satisfy this need in cyclostratigraphy, we initiate a comparable framework for the community. The aims are to investigate and quantify reproducibility of, and uncertainties related to cyclostratigraphic studies and to provide a platform to discuss the merits and pitfalls of different methodologies, and their applicabilities. With this poster, we ask the feedback from the community on how to design this comparative framework in a useful, meaningful and productive manner. In parallel, we would like to discuss how reproducibility should be tested and what uncertainties should stand for in cyclostratigraphy. On the other hand, we intend to trigger interest for a cyclostratigraphic intercomparison project. This intercomparison project would imply the analysis of artificial and genuine geological records by individual researchers. All participants would be free to determine their method of choice. However, a handful of criterions will be required for an outcome to be comparable. The different results would be compared (e.g. during a workshop or a special session), and the lessons learned from the comparison could potentially be reported in a review paper. The aim of an intercomparison project is not to rank the different methods according to their merits, but to get insight into which specific methods are most suitable for which specific problems, and obtain more information on different sources of uncertainty. As this intercomparison project should be supported by the broader cyclostratigraphic community, we open the floor for suggestions, ideas and practical remarks.

Spectroradiometer Intercomparison and Impact on Characterizing Photovoltaic Device Performance: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, A.; Andreas, A.; Ottoson, L.

2014-11-01

Indoor and outdoor testing of photovoltaic (PV) device performance requires the use of solar simulators and natural solar radiation, respectively. This performance characterization requires accurate knowledge of spectral irradiance distribution that is incident on the devices. Spectroradiometers are used to measure the spectral distribution of solar simulators and solar radiation. On September 17, 2013, a global spectral irradiance intercomparison using spectroradiometers was organized by the Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory (NREL). This paper presents highlights of the results of this first intercomparison, which will help to decrease systematic inter-laboratory differences in the measurements ofmore » the outputs or efficiencies of PV devices and harmonize laboratory experimental procedures.« less

Traceable calibration of ultraviolet meters used with broadband, extended sources.

PubMed

Coleman, A J; Collins, M; Saunders, J E

2000-01-01

A calibration system has been developed to provide increased accuracy in the measurement of the irradiance responsivity appropriate for UV meters used with broadband, extended sources of the type employed in phototherapy. The single wavelength responsivity of the test meter is obtained in the wavelength range 250-400 nm by intercomparison with a transfer standard meter in a narrow, monochromatic beam. Traceability to primary standard irradiance scales is provided via the National Measurement System with a best uncertainty of 7% (at 95% confidence). The effective responsivity of the test meter, when used with broadband extended sources, is calculated using the measured spectral and angular response of the meter and tabulated data on the spectral and spatial characteristics of the source radiance. The uncertainty in the effective responsivity, independent of the source variability, is estimated to be 10% (at 95% confidence). The advantages of this calibration system over existing approaches are discussed.

Multi-Wheat-Model Ensemble Responses to Interannual Climate Variability

NASA Technical Reports Server (NTRS)

Ruane, Alex C.; Hudson, Nicholas I.; Asseng, Senthold; Camarrano, Davide; Ewert, Frank; Martre, Pierre; Boote, Kenneth J.; Thorburn, Peter J.; Aggarwal, Pramod K.; Angulo, Carlos

2016-01-01

We compare 27 wheat models' yield responses to interannual climate variability, analyzed at locations in Argentina, Australia, India, and The Netherlands as part of the Agricultural Model Intercomparison and Improvement Project (AgMIP) Wheat Pilot. Each model simulated 1981e2010 grain yield, and we evaluate results against the interannual variability of growing season temperature, precipitation, and solar radiation. The amount of information used for calibration has only a minor effect on most models' climate response, and even small multi-model ensembles prove beneficial. Wheat model clusters reveal common characteristics of yield response to climate; however models rarely share the same cluster at all four sites indicating substantial independence. Only a weak relationship (R2 0.24) was found between the models' sensitivities to interannual temperature variability and their response to long-termwarming, suggesting that additional processes differentiate climate change impacts from observed climate variability analogs and motivating continuing analysis and model development efforts.

A standard test case suite for two-dimensional linear transport on the sphere: results from a collection of state-of-the-art schemes

NASA Astrophysics Data System (ADS)

Lauritzen, P. H.; Ullrich, P. A.; Jablonowski, C.; Bosler, P. A.; Calhoun, D.; Conley, A. J.; Enomoto, T.; Dong, L.; Dubey, S.; Guba, O.; Hansen, A. B.; Kaas, E.; Kent, J.; Lamarque, J.-F.; Prather, M. J.; Reinert, D.; Shashkin, V. V.; Skamarock, W. C.; Sørensen, B.; Taylor, M. A.; Tolstykh, M. A.

2013-09-01

Recently, a standard test case suite for 2-D linear transport on the sphere was proposed to assess important aspects of accuracy in geophysical fluid dynamics with a "minimal" set of idealized model configurations/runs/diagnostics. Here we present results from 19 state-of-the-art transport scheme formulations based on finite-difference/finite-volume methods as well as emerging (in the context of atmospheric/oceanographic sciences) Galerkin methods. Discretization grids range from traditional regular latitude-longitude grids to more isotropic domain discretizations such as icosahedral and cubed-sphere tessellations of the sphere. The schemes are evaluated using a wide range of diagnostics in idealized flow environments. Accuracy is assessed in single- and two-tracer configurations using conventional error norms as well as novel diagnostics designed for climate and climate-chemistry applications. In addition, algorithmic considerations that may be important for computational efficiency are reported on. The latter is inevitably computing platform dependent, The ensemble of results from a wide variety of schemes presented here helps shed light on the ability of the test case suite diagnostics and flow settings to discriminate between algorithms and provide insights into accuracy in the context of global atmospheric/ocean modeling. A library of benchmark results is provided to facilitate scheme intercomparison and model development. Simple software and data-sets are made available to facilitate the process of model evaluation and scheme intercomparison.

A standard test case suite for two-dimensional linear transport on the sphere: results from a collection of state-of-the-art schemes

NASA Astrophysics Data System (ADS)

Lauritzen, P. H.; Ullrich, P. A.; Jablonowski, C.; Bosler, P. A.; Calhoun, D.; Conley, A. J.; Enomoto, T.; Dong, L.; Dubey, S.; Guba, O.; Hansen, A. B.; Kaas, E.; Kent, J.; Lamarque, J.-F.; Prather, M. J.; Reinert, D.; Shashkin, V. V.; Skamarock, W. C.; Sørensen, B.; Taylor, M. A.; Tolstykh, M. A.

2014-01-01

Recently, a standard test case suite for 2-D linear transport on the sphere was proposed to assess important aspects of accuracy in geophysical fluid dynamics with a "minimal" set of idealized model configurations/runs/diagnostics. Here we present results from 19 state-of-the-art transport scheme formulations based on finite-difference/finite-volume methods as well as emerging (in the context of atmospheric/oceanographic sciences) Galerkin methods. Discretization grids range from traditional regular latitude-longitude grids to more isotropic domain discretizations such as icosahedral and cubed-sphere tessellations of the sphere. The schemes are evaluated using a wide range of diagnostics in idealized flow environments. Accuracy is assessed in single- and two-tracer configurations using conventional error norms as well as novel diagnostics designed for climate and climate-chemistry applications. In addition, algorithmic considerations that may be important for computational efficiency are reported on. The latter is inevitably computing platform dependent. The ensemble of results from a wide variety of schemes presented here helps shed light on the ability of the test case suite diagnostics and flow settings to discriminate between algorithms and provide insights into accuracy in the context of global atmospheric/ocean modeling. A library of benchmark results is provided to facilitate scheme intercomparison and model development. Simple software and data sets are made available to facilitate the process of model evaluation and scheme intercomparison.

High Resolution Model Intercomparison Project (HighResMIP v1.0) for CMIP6

NASA Astrophysics Data System (ADS)

Haarsma, Reindert J.; Roberts, Malcolm J.; Vidale, Pier Luigi; Senior, Catherine A.; Bellucci, Alessio; Bao, Qing; Chang, Ping; Corti, Susanna; Fučkar, Neven S.; Guemas, Virginie; von Hardenberg, Jost; Hazeleger, Wilco; Kodama, Chihiro; Koenigk, Torben; Leung, L. Ruby; Lu, Jian; Luo, Jing-Jia; Mao, Jiafu; Mizielinski, Matthew S.; Mizuta, Ryo; Nobre, Paulo; Satoh, Masaki; Scoccimarro, Enrico; Semmler, Tido; Small, Justin; von Storch, Jin-Song

2016-11-01

Robust projections and predictions of climate variability and change, particularly at regional scales, rely on the driving processes being represented with fidelity in model simulations. The role of enhanced horizontal resolution in improved process representation in all components of the climate system is of growing interest, particularly as some recent simulations suggest both the possibility of significant changes in large-scale aspects of circulation as well as improvements in small-scale processes and extremes. However, such high-resolution global simulations at climate timescales, with resolutions of at least 50 km in the atmosphere and 0.25° in the ocean, have been performed at relatively few research centres and generally without overall coordination, primarily due to their computational cost. Assessing the robustness of the response of simulated climate to model resolution requires a large multi-model ensemble using a coordinated set of experiments. The Coupled Model Intercomparison Project 6 (CMIP6) is the ideal framework within which to conduct such a study, due to the strong link to models being developed for the CMIP DECK experiments and other model intercomparison projects (MIPs). Increases in high-performance computing (HPC) resources, as well as the revised experimental design for CMIP6, now enable a detailed investigation of the impact of increased resolution up to synoptic weather scales on the simulated mean climate and its variability. The High Resolution Model Intercomparison Project (HighResMIP) presented in this paper applies, for the first time, a multi-model approach to the systematic investigation of the impact of horizontal resolution. A coordinated set of experiments has been designed to assess both a standard and an enhanced horizontal-resolution simulation in the atmosphere and ocean. The set of HighResMIP experiments is divided into three tiers consisting of atmosphere-only and coupled runs and spanning the period 1950-2050, with the possibility of extending to 2100, together with some additional targeted experiments. This paper describes the experimental set-up of HighResMIP, the analysis plan, the connection with the other CMIP6 endorsed MIPs, as well as the DECK and CMIP6 historical simulations. HighResMIP thereby focuses on one of the CMIP6 broad questions, "what are the origins and consequences of systematic model biases?", but we also discuss how it addresses the World Climate Research Program (WCRP) grand challenges.

BRDF Characterization and Calibration Inter-Comparison between Terra MODIS, Aqua MODIS, and S-NPP VIIRS

NASA Technical Reports Server (NTRS)

Chang, Tiejun; Xiong, Xiaoxiong (Jack); Angal, Amit; Wu, Aisheng

2016-01-01

The inter-comparison of reflective solar bands (RSB) between Terra MODIS, Aqua MODIS, and SNPP VIIRS is very important for assessment of each instrument's calibration and to identify calibration improvements. One of the limitations of using their ground observations for the assessment is a lack of the simultaneous nadir overpasses (SNOs) over selected pseudo-invariant targets. In addition, their measurements over a selected Earth view target have significant difference in solar and view angles, and these differences magnify the effects of Bidirectional Reflectance Distribution Function (BRDF). In this work, an inter-comparison technique using a semi-empirical BRDF model is developed for reflectance correction. BRDF characterization requires a broad coverage of solar and view angles in the measurements over selected pseudo-invariant targets. Reflectance measurements over Libya 1, 2, and 4 desert sites from both the Aqua and Terra MODIS are regressed to a BRDF model with an adjustable coefficient accounting for the calibration difference between the two instruments. The BRDF coefficients for three desert sites for MODIS bands 1 to 9 are derived and the wavelength dependencies are presented. The analysis and inter-comparison are for MODIS bands 1 to 9 and VIIRS moderate resolution radiometric bands (M bands) M1, M2, M4, M5, M7, M8, M10 and imaging bands (I bands) I1-I3. Results show that the ratios from different sites are in good agreement. The ratios between Terra and Aqua MODIS from year 2003 to 2014 are presented. The inter-comparison between MODIS and VIIRS are analyzed for year 2014.

An Intercomparison of 2-D Models Within a Common Framework

NASA Technical Reports Server (NTRS)

Weisenstein, Debra K.; Ko, Malcolm K. W.; Scott, Courtney J.; Jackman, Charles H.; Fleming, Eric L.; Considine, David B.; Kinnison, Douglas E.; Connell, Peter S.; Rotman, Douglas A.; Bhartia, P. K. (Technical Monitor)

2002-01-01

A model intercomparison among the Atmospheric and Environmental Research (AER) 2-D model, the Goddard Space Flight Center (GSFC) 2-D model, and the Lawrence Livermore National Laboratory 2-D model allows us to separate differences due to model transport from those due to the model's chemical formulation. This is accomplished by constructing two hybrid models incorporating the transport parameters of the GSFC and LLNL models within the AER model framework. By comparing the results from the native models (AER and e.g. GSFC) with those from the hybrid model (e.g. AER chemistry with GSFC transport), differences due to chemistry and transport can be identified. For the analysis, we examined an inert tracer whose emission pattern is based on emission from a High Speed Civil Transport (HSCT) fleet; distributions of trace species in the 2015 atmosphere; and the response of stratospheric ozone to an HSCT fleet. Differences in NO(y) in the upper stratosphere are found between models with identical transport, implying different model representations of atmospheric chemical processes. The response of O3 concentration to HSCT aircraft emissions differs in the models from both transport-dominated differences in the HSCT-induced perturbations of H2O and NO(y) as well as from differences in the model represent at ions of O3 chemical processes. The model formulations of cold polar processes are found to be the most significant factor in creating large differences in the calculated ozone perturbations

Climate model response from the Geoengineering Model Intercomparison Project (GeoMIP)

NASA Astrophysics Data System (ADS)

Kravitz, Ben; Caldeira, Ken; Boucher, Olivier; Robock, Alan; Rasch, Philip J.; Alterskjær, Kari; Karam, Diana Bou; Cole, Jason N. S.; Curry, Charles L.; Haywood, James M.; Irvine, Peter J.; Ji, Duoying; Jones, Andy; Kristjánsson, Jón Egill; Lunt, Daniel J.; Moore, John C.; Niemeier, Ulrike; Schmidt, Hauke; Schulz, Michael; Singh, Balwinder; Tilmes, Simone; Watanabe, Shingo; Yang, Shuting; Yoon, Jin-Ho

2013-08-01

geoengineering—deliberate reduction in the amount of solar radiation retained by the Earth—has been proposed as a means of counteracting some of the climatic effects of anthropogenic greenhouse gas emissions. We present results from Experiment G1 of the Geoengineering Model Intercomparison Project, in which 12 climate models have simulated the climate response to an abrupt quadrupling of CO2 from preindustrial concentrations brought into radiative balance via a globally uniform reduction in insolation. Models show this reduction largely offsets global mean surface temperature increases due to quadrupled CO2 concentrations and prevents 97% of the Arctic sea ice loss that would otherwise occur under high CO2 levels but, compared to the preindustrial climate, leaves the tropics cooler (-0.3 K) and the poles warmer (+0.8 K). Annual mean precipitation minus evaporation anomalies for G1 are less than 0.2 mm day-1 in magnitude over 92% of the globe, but some tropical regions receive less precipitation, in part due to increased moist static stability and suppression of convection. Global average net primary productivity increases by 120% in G1 over simulated preindustrial levels, primarily from CO2 fertilization, but also in part due to reduced plant heat stress compared to a high CO2 world with no geoengineering. All models show that uniform solar geoengineering in G1 cannot simultaneously return regional and global temperature and hydrologic cycle intensity to preindustrial levels.

TL detectors for gamma ray dose measurements in criticality accidents.

PubMed

Miljanić, Saveta; Zorko, Benjamin; Gregori, Beatriz; Knezević, Zeljka

2007-01-01

Determination of gamma ray dose in mixed neutron+gamma ray fields is still a demanding task. Dosemeters used for gamma ray dosimetry are usually in some extent sensitive to neutrons and their response variations depend on neutron energy i.e., on neutron spectra. Besides, it is necessary to take into account the energy dependence of dosemeter responses to gamma rays. In this work, several types of thermoluminescent detectors (TLD) placed in different holders used for gamma ray dose determination in the mixed fields were examined. Dosemeters were from three different institutions: Ruder Bosković Institute (RBI), Croatia, JoZef Stefan Institute (JSI), Slovenia and Autoridad Regulatoria Nuclear (ARN), Argentina. All dosemeters were irradiated during the International Intercomparison of Criticality Accident Dosimetry Systems at the SILENE Reactor, Valduc, June 2002. Three accidental scenarios were reproduced and in each irradiation the dosemeters were exposed placed on the front of phantom and 'free in air'. Following types of TLDs were used: 7LiF (TLD-700), CaF2:Mn and Al2O3:Mg,Y-all from RBI; CaF2:Mn from JSI and 7LiF (TLD-700) from ARN. Reported doses were compared with the reference values as well as with the values obtained from the results of all participants. The results show satisfactory agreement with other dosimetry systems used in the Intercomparison. The influence of different types of holders and applied corrections of dosemeters' readings are discussed.

Climate Model Response from the Geoengineering Model Intercomparison Project (GeoMIP)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kravitz, Benjamin S.; Caldeira, Ken; Boucher, Olivier

2013-08-09

Solar geoengineering—deliberate reduction in the amount of solar radiation retained by the Earth—has been proposed as a means of counteracting some of the climatic effects of anthropogenic greenhouse gas emissions. We present results from Experiment G1 of the Geoengineering Model Intercomparison Project, in which 12 climate models have simulated the climate response to an abrupt quadrupling of CO2 from preindustrial concentrations brought into radiative balance via a globally uniform reduction in insolation. Models show this reduction largely offsets global mean surface temperature increases due to quadrupled CO2 concentrations and prevents 97% of the Arctic sea ice loss that would otherwisemore » occur under high CO2 levels but, compared to the preindustrial climate, leaves the tropics cooler (-0.3 K) and the poles warmer (+0.8 K). Annual mean precipitation minus evaporation anomalies for G1 are less than 0.2mmday-1 in magnitude over 92% of the globe, but some tropical regions receive less precipitation, in part due to increased moist static stability and suppression of convection. Global average net primary productivity increases by 120% in G1 over simulated preindustrial levels, primarily from CO2 fertilization, but also in part due to reduced plant heat stress compared to a high CO2 world with no geoengineering. All models show that uniform solar geoengineering in G1 cannot simultaneously return regional and global temperature and hydrologic cycle intensity to preindustrial levels.« less

The tropical rain belts with an annual cycle and a continent model intercomparison project: TRACMIP

DOE PAGES

Voigt, Aiko; Biasutti, Michela; Scheff, Jacob; ...

2016-11-16

This paper introduces the Tropical Rain belts with an Annual cycle and a Continent Model Intercomparison Project (TRACMIP). TRACMIP studies the dynamics of tropical rain belts and their response to past and future radiative forcings through simulations with 13 comprehensive and one simplified atmosphere models coupled to a slab ocean and driven by seasonally-varying insolation. Five idealized experiments, two with an aquaplanet setup and three with a setup with an idealized tropical continent, fill the space between prescribed-SST aquaplanet simulations and realistic simulations provided by CMIP5/6. The simulations reproduce key features of the present-day climate and expected future climate change,more » including an annual-mean intertropical convergence zone (ITCZ) that is located north of the equator and Hadley cells and eddy-driven jets that are similar to the present-day climate. Quadrupling CO 2 leads to a northward ITCZ shift and preferential warming in Northern high-latitudes. The simulations show interesting CO 2-induced changes in the seasonal excursion of the ITCZ and indicate a possible state-dependence of climate sensitivity. The inclusion of an idealized continent modulates both the control climate and the response to increased CO 2; for example it reduces the northward ITCZ shift associated with warming and, in some models, climate sensitivity. In response to eccentricity-driven seasonal insolation changes, seasonal changes in oceanic rainfall are best characterized as a meridional dipole, while seasonal continental rainfall changes tend to be symmetric about the equator. Finally, this survey illustrates TRACMIP’s potential to engender a deeper understanding of global and regional climate phenomena and to address pressing questions on past and future climate change.« less

The Tropical Rain Belts with an Annual Cycle and a Continent Model Intercomparison Project: TRACMIP

NASA Technical Reports Server (NTRS)

Voigt, Aiko; Biasutti, Michela; Scheff, Jacob; Bader, Juergen; Bordoni, Simona; Codron, Francis; Dixon, Ross D.; Jonas, Jeffrey; Kang, Sarah M.; Klingaman, Nicholas P.;

Assessing the Application of Cloud-Shadow Atmospheric Correction Algorithm on HICO

DTIC Science & Technology

2014-05-01

multiple times and intercompare the results to assess variability in the retrieved reflectance spectra. Retrieved chlorophyll values from this...intercomparison are similar and also agree well with the In situ chlorophyll measurements. 15. SUBJECT TERMS Atmospheric correction, cloud-shadow...reflectance spectra. Re- trieved chlorophyll values from this intercomparison are similar and also agree well with the in situ chlorophyll measurements

Development of phantom and methodology for 3D and 4D dose intercomparisons for advanced lung radiotherapy

NASA Astrophysics Data System (ADS)

Caloz, Misael; Kafrouni, Marilyne; Leturgie, Quentin; Corde, Stéphanie; Downes, Simon; Lehmann, Joerg; Thwaites, David

2015-01-01

There are few reported intercomparisons or audits of combinations of advanced radiotherapy methods, particularly for 4D treatments. As part of an evaluation of the implementation of advanced radiotherapy technology, a phantom and associated methods, initially developed for in-house commissioning and QA of 4D lung treatments, has been developed further with the aim of using it for end-to-end dose intercomparison of 4D treatment planning and delivery. The respiratory thorax phantom can house moving inserts with variable speed (breathing rate) and motion amplitude. In one set-up mode it contains a small ion chamber for point dose measurements, or alternatively it can hold strips of radiochromic film to measure dose distributions. Initial pilot and feasibility measurements have been carried out in one hospital to thoroughly test the methods and procedures before using it more widely across a range of hospitals and treatment systems. Overall, the results show good agreement between measured and calculated doses and distributions, supporting the use of the phantom and methodology for multi-centre intercomparisons. However, before wider use, refinements of the method and analysis are currently underway particularly for the film measurements.

A Comparison of Aircraft and Ground-Based Measurements at Mauna Loa Observatory, Hawaii, During GTE PEM-West and MLOPEX 2

NASA Technical Reports Server (NTRS)

Atlas, E.; Ridley, B.; Walega, J.; Greenberg, J.; Kok, G.; Staffelbach, T.; Schauffler, S.; Lind, J.; Huebler, G.; Norton, R.

1996-01-01

During October 19-20, 1991, one flight of the NASA Global Tropospheric Experiment (GTE) Pacific Exploratory Mission (PEM-West A) mission was conducted near Hawaii as an intercomparison with ground-based measurements of the Mauna Loa Observatory Photochemistry Experiment (MLOPEX 2) and the NOAA Climate Modeling and Diagnostics Laboratory (CMDL). Ozone, reactive nitrogen species, peroxides, hydrocarbons, and halogenated hydrocarbons were measured by investigators aboard the DC-8 aircraft and at the ground site. Lidar cross sections of ozone revealed a complex air mass structure near the island of Hawaii which was evidenced by large variation in some trace gas mixing ratios. This variation limited the time and spatial scales for direct measurement intercomparisons. Where differences occurred between measurements in the same air masses, the intercomparison suggested that biases for some trace gases was due to different calibration scales or, in some cases, instrumental or sampling biases. Relatively large uncertainties were associated with those trace gases present in the low parts per trillion by volume range. Trace gas correlations were used to expand the scope of the intercomparison to identify consistent trends between the different data sets.

Revision of the Dobson total ozone series at Hohenpeissenberg

NASA Technical Reports Server (NTRS)

Koehler, U.

1994-01-01

Total ozone measurements with the Dobson No. 104 (D 104) have been performed at the Meteorological Observatory Hohenpeissenberg since 1967. A critical review of this time series and the comparison with other instruments like TOMS or Brewer spectrophotometer revealed some intervals with uncertainties. Especially in the early eighties a monthly mean bias of about minus 3 percent to TOMS-data with annual variations depending on the mean sun-height exists. An extreme amplitude of 5.6 percent occurs in 1980 with minus 0.76 percent (February) and minus 6.36 percent (July). Two different methods were applied to reprocess the Dobson data set. A comparison of the differently recalculated data showed, that the application of N-corrections by means of the standard-lamp tests starting from the reference values of the Arosa Intercomparison 1986 yields better results than the N-corrections based on a Langley-pilot of the Arosa Intercomparison 1978. The extreme amplitude of the year 1980 is now reduced to 3.02 percent. There is still a slight drift in the monthly and yearly mean differences between TOMS and revised Dobson data. It cannot be excluded, that the satellite data may be responsible for the trend.

Intercomparison of Global Precipitation Products: The Third Precipitation Intercomparison Project (PIP-3)

NASA Technical Reports Server (NTRS)

Adler, Robert F.; Kidd, Christopher; Petty, Grant; Morrissey, Mark; Goodman, H. Michael; Einaudi, Franco (Technical Monitor)

2000-01-01

A set of global, monthly rainfall products has been intercompared to understand the quality and utility of the estimates. The products include 25 observational (satellite-based), four model and two climatological products. The results of the intercomparison indicate a very large range (factor of two or three) of values when all products are considered. The range of values is reduced considerably when the set of observational products is limited to those considered quasi-standard. The model products do significantly poorer in the tropics, but are competitive with satellite-based fields in mid-latitudes over land. Over ocean, products are compared to frequency of precipitation from ship observations. The evaluation of the observational products point to merged data products (including rain gauge information) as providing the overall best results.

The Program for climate Model diagnosis and Intercomparison: 20-th anniversary Symposium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Potter, Gerald L; Bader, David C; Riches, Michael

Twenty years ago, W. Lawrence (Larry) Gates approached the U.S. Department of Energy (DOE) Office of Energy Research (now the Office of Science) with a plan to coordinate the comparison and documentation of climate model differences. This effort would help improve our understanding of climate change through a systematic approach to model intercomparison. Early attempts at comparing results showed a surprisingly large range in control climate from such parameters as cloud cover, precipitation, and even atmospheric temperature. The DOE agreed to fund the effort at the Lawrence Livermore National Laboratory (LLNL), in part because of the existing computing environment andmore » because of a preexisting atmospheric science group that contained a wide variety of expertise. The project was named the Program for Climate Model Diagnosis and Intercomparison (PCMDI), and it has changed the international landscape of climate modeling over the past 20 years. In spring 2009 the DOE hosted a 1-day symposium to celebrate the twentieth anniversary of PCMDI and to honor its founder, Larry Gates. Through their personal experiences, the morning presenters painted an image of climate science in the 1970s and 1980s, that generated early support from the international community for model intercomparison, thereby bringing PCMDI into existence. Four talks covered Gates's early contributions to climate research at the University of California, Los Angeles (UCLA), the RAND Corporation, and Oregon State University through the founding of PCMDI to coordinate the Atmospheric Model Intercomparison Project (AMIP). The speakers were, in order of presentation, Warren Washington [National Center for Atmospheric Research (NCAR)], Kelly Redmond (Western Regional Climate Center), George Boer (Canadian Centre for Climate Modelling and Analysis), and Lennart Bengtsson [University of Reading, former director of the European Centre for Medium-Range Weather Forecasts (ECMWF)]. The afternoon session emphasized the scientific ideas that are the basis of PCMDI's success, summarizing their evolution and impact. Four speakers followed the various PCMDI-supported climate model intercomparison projects, beginning with early work on cloud representations in models, presented by Robert D. Cess (Distinguished Professor Emeritus, Stony Brook University), and then the latest Cloud Feedback Model Intercomparison Projects (CFMIPs) led by Sandrine Bony (Laboratoire de M'©t'©orologie Dynamique). Benjamin Santer (LLNL) presented a review of the climate change detection and attribution (D & A) work pioneered at PCMDI, and Gerald A. Meehl (NCAR) ended the day with a look toward the future of climate change research.« less

Summary Report for the Environmental Protection Agency MERL/FRMAC Mission Alignment Exercise held at the Environmental Protection Agency Facility on June 24-26 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, Mark B.; Shanks, Sonoya Toyoko; Fournier, Sean Donovan

From June 24th thru June 26th 2014, members of the Federal Radiological Monitoring and Assessment Center (FRMAC), FRMAC Fly Away Laboratory, and the Environmental Protection Agency (EPA) participated in a joint nuclear incident emergency response/round robin exercise at the EPA facility in Las Vegas, Nevada. The purpose of this exercise was to strengthen the interoperability relationship between the FRMAC Fly Away Laboratory (FAL) and the EPA Mobile Environmental Radiation Laboratory (MERL) stationed in Las Vegas, Nevada. The exercise was designed to allow for immediate delivery of pre-staged, spiked samples to the EPA MERL and the FAL for sample preparation andmore » radiological analysis. Upon completion of laboratory analysis, data was reviewed and submitted back to the FRMAC via an electronic data deliverable (EDD). In order to conduct a laboratory inter-comparison study, samples were then traded between the two laboratories and re-counted. As part of the exercise, an evaluation was conducted to identify gaps and potential areas for improvements for FRMAC, FAL and EPA operations. Additionally, noteworthy practices and potential future areas of interoperability opportunities between the FRMAC, FAL and EPA were acknowledged. The exercise also provided a unique opportunity for FRMAC personnel to observe EPA sample receipt and sample preparation processes and to gain familiarity with the MERL laboratory instrumentation and radiation detection capabilities. The areas for potential improvements and interoperability from this exercise will be critical for developing a more efficient, integrated response for future interactions between the FRMAC and EPA MERL assets.« less

External Influences on Modeled and Observed Cloud Trends

NASA Technical Reports Server (NTRS)

Marvel, Kate; Zelinka, Mark; Klein, Stephen A.; Bonfils, Celine; Caldwell, Peter; Doutriaux, Charles; Santer, Benjamin D.; Taylor, Karl E.

2015-01-01

Understanding the cloud response to external forcing is a major challenge for climate science. This crucial goal is complicated by intermodel differences in simulating present and future cloud cover and by observational uncertainty. This is the first formal detection and attribution study of cloud changes over the satellite era. Presented herein are CMIP5 (Coupled Model Intercomparison Project - Phase 5) model-derived fingerprints of externally forced changes to three cloud properties: the latitudes at which the zonally averaged total cloud fraction (CLT) is maximized or minimized, the zonal average CLT at these latitudes, and the height of high clouds at these latitudes. By considering simultaneous changes in all three properties, the authors define a coherent multivariate fingerprint of cloud response to external forcing and use models from phase 5 of CMIP (CMIP5) to calculate the average time to detect these changes. It is found that given perfect satellite cloud observations beginning in 1983, the models indicate that a detectable multivariate signal should have already emerged. A search is then made for signals of external forcing in two observational datasets: ISCCP (International Satellite Cloud Climatology Project) and PATMOS-x (Advanced Very High Resolution Radiometer (AVHRR) Pathfinder Atmospheres - Extended). The datasets are both found to show a poleward migration of the zonal CLT pattern that is incompatible with forced CMIP5 models. Nevertheless, a detectable multivariate signal is predicted by models over the PATMOS-x time period and is indeed present in the dataset. Despite persistent observational uncertainties, these results present a strong case for continued efforts to improve these existing satellite observations, in addition to planning for new missions.

A Bootstrap Algorithm for Mixture Models and Interval Data in Inter-Comparisons

DTIC Science & Technology

2001-07-01

parametric bootstrap. The present algorithm will be applied to a thermometric inter-comparison, where data cannot be assumed to be normally distributed. 2 Data...experimental methods, used in each laboratory) often imply that the statistical assumptions are not satisfied, as for example in several thermometric ...triangular). Indeed, in thermometric experiments these three probabilistic models can represent several common stochastic variabilities for

Intercomparison of TCCON and MUSICA Water Vapour Products

NASA Astrophysics Data System (ADS)

Weaver, D.; Strong, K.; Deutscher, N. M.; Schneider, M.; Blumenstock, T.; Robinson, J.; Notholt, J.; Sherlock, V.; Griffith, D. W. T.; Barthlott, S.; García, O. E.; Smale, D.; Palm, M.; Jones, N. B.; Hase, F.; Kivi, R.; Ramos, Y. G.; Yoshimura, K.; Sepúlveda, E.; Gómez-Peláez, Á. J.; Gisi, M.; Kohlhepp, R.; Warneke, T.; Dohe, S.; Wiegele, A.; Christner, E.; Lejeune, B.; Demoulin, P.

2014-12-01

We present an intercomparison between the water vapour products from the Total Carbon Column Observing Network (TCCON) and the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA), two datasets from ground-based Fourier Transform InfraRed (FTIR) spectrometers with good global representation. Where possible, comparisons to radiosondes are also included. The near-infrared TCCON measurements are optimized to provide precise monitoring of greenhouse gases for carbon cycle studies; however, TCCON's retrievals also produce water vapour products. The mid-infrared MUSICA products result from retrievals optimized to give precise and accurate information about H2O, HDO, and δD. The MUSICA water vapour products have been validated by extensive intercomparisons with H2O and δD in-situ measurements made from ground, radiosonde, and aircraft (Schneider et al. 2012, 2014), as well as by intercomparisons with satellite-based H2O and δD remote sensing measurements (Wiegele et al., 2014). This dataset provides a valuable reference point for other measurements of water vapour. This study is motivated by the limited intercomparisons performed for TCCON water vapour products and limited characterisation of their uncertainties. We compare MUSICA and TCCON products to assess the potential for TCCON measurements to contribute to studies of the water cycle, water vapour's role in climate and use as a tracer for atmospheric dynamics, and to evaluate the performance of climate models. The TCCON and MUSICA products result from measurements taken using the same FTIR instruments, enabling a comparison with constant instrumentation. The retrieval techniques differ, however, in their method and a priori information. We assess the impact of these differences and characterize the comparability of the TCCON and MUSICA datasets.

An evaluation of the Wyoming Gauge System for snowfall measurement

USGS Publications Warehouse

Yang, Daqing; Kane, Douglas L.; Hinzman, Larry D.; Goodison, Barry E.; Metcalfe, John R.; Louie, Paul Y.T.; Leavesley, George H.; Emerson, Douglas G.; Hanson, Clayton L.

2000-01-01

The Wyoming snow fence (shield) has been widely used with precipitation gauges for snowfall measurement at more than 25 locations in Alaska since the late 1970s. This gauge's measurements have been taken as the reference for correcting wind‐induced gauge undercatch of snowfall in Alaska. Recently, this fence (shield) was tested in the World Meteorological Organization Solid Precipitation Measurement Intercomparison Project at four locations in the United States of America and Canada for six winter seasons. At the Intercomparison sites an octagonal vertical Double Fence with a Russian Tretyakov gauge or a Universal Belfort recording gauge was installed and used as the Intercomparison Reference (DFIR) to provide true snowfall amounts for this Intercomparison experiment. The Intercomparison data collected were compiled at the four sites that represent a variety of climate, terrain, and exposure. On the basis of these data sets the performance of the Wyoming gauge system for snowfall observations was carefully evaluated against the DFIR and snow cover data. The results show that (1) the mean snow catch efficiency of the Wyoming gauge compared with the DFIR is about 80–90%, (2) there exists a close linear relation between the measurements of the two gauge systems and this relation may serve as a transfer function to adjust the Wyoming gauge records to obtain an estimate of the true snowfall amount, (3) catch efficiency of the Wyoming gauge does not change with wind speed and temperature, and (4) Wyoming gauge measurements are generally compatible to the snowpack water equivalent at selected locations in northern Alaska. These results are important to our effort of determining true snowfall amounts in the high latitudes, and they are also useful for regional hydrologic and climatic analyses.

Water vapour intercomparison effort in the frame of HyMeX-SOP1

NASA Astrophysics Data System (ADS)

Summa, Donato; Di Girolamo, Paolo; Stelitano, Dario; Cacciani, Marco; Flamant, Cyrille; Chazette, Patrick; Ducrocq, Véronique; Nuret, Mathieu; Fourié, Nadia; Richard, Evelyne

2014-05-01

A water vapour intercomparison effort, involving airborne and ground-based water vapour lidar systems and mesoscale models, was carried out in the framework of the international HyMeX (Hydrological cycle in the Mediterranean Experiment) dedicated to the hydrological cycle and related high-impact events. Within HyMeX, a major field campaign was dedicated to heavy precipitation and flash flood events from 5 September to 6 November 2012. The 2 month field campaign took place over the Northwestern Mediterranean Sea and its surrounding coastal regions in France, Italy, and Spain. The main objective of this work is to provide accurate error estimates for the lidar systems i.e. the ground-based Raman lidar BASIL and the CNRS DIAL Leandre 2 on board the ATR42, as well as use BASIL data to validate mesoscale model results from the MESO NH and Arome WMED. The effort will benefit from the few dedicated ATR42 flights in the frame of the EUFAR Project "WaLiTemp". In the present work our attention was focused on two specific case studies: 13 September and 2 October in the altitude region 0.5 - 5.5 km. Comparisons between the ground-based Raman lidar BASIL and the airborne CNRS DIAL indicate a mean relative bias between the two sensors of 6.5%, while comparisons between BASIL and CNRS DIAL vs. the radiosondes indicate a bias of 2.6 and -3.5 %, respectively. The bias of BASIL vs. the ATR insitu sensor indicate a bias of -20.4 %. Specific attention will also be dedicated to the WALI/BASIL intercomparison effort which took place in Candillargues on 30 October 2012. Specific results from this intercomparison effort and from the intercomparison between BASIL and Meso-NH/AROME-WMed will be illustrated and discussed at the Conference.

An international marine-atmospheric {sup 222}Rn measurement intercomparison in Bermuda. Part 2: Results for the participating laboratories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colle, R.; Unterweger, M.P.; Hutchinson, J.M.R.

1996-01-01

As part of an international measurement intercomparison of instruments used to measure atmospheric {sup 222}Rn, four participating laboratories made nearly simultaneous measurements of {sup 222}Rn activity concentration in commonly sampled, ambient air over approximately a 2 week period, and three of these four laboratories participated in the measurement comparison of 14 introduced samples with known, but undisclosed (blind) {sup 222}Rn activity concentration. The exercise was conducted in Bermuda in October 1991. The {sup 222}Rn activity concentrations in ambient Bermudian air over the course of the intercomparison ranged from a few hundredths of a Bq {center_dot} m{sup {minus}3} to about 2more » Bq {center_dot} m{sup {minus}3}, while the standardized sample additions covered a range from approximately 2.5 Bq {center_dot} m{sup {minus}3} to 35 Bq {center_dot} m{sup {minus}3}. The overall uncertainty in the latter concentrations was in the general range of 10%, approximating a 3 standard deviation uncertainty interval. The results of the intercomparison indicated that two of the laboratories were within very good agreement with the standard additions, and almost within expected statistical variations. These same two laboratories, however, at lower ambient concentrations, exhibited a systematic difference with an averaged offset of roughly 0.3 Bq {center_dot} m{sup {minus}3}. The third laboratory participating in the measurement of standardized sample additions was systematically low by about 65% to 70%, with respect to the standard addition which was also confirmed in their ambient air concentration measurements. The fourth laboratory, participating in only the ambient measurement part of the intercomparison, was also systematically low by at least 40% with respect to the first two laboratories.« less

Annular mode changes in the CMIP5 simulations

NASA Astrophysics Data System (ADS)

Gillett, N. P.; Fyfe, J. C.

2013-03-01

We investigate simulated changes in the annular modes in historical and RCP 4.5 scenario simulations of 37 models from the fifth Coupled Model Intercomparison Project (CMIP5), a much larger ensemble of models than has previously been used to investigate annular mode trends, with improved resolution and forcings. The CMIP5 models on average simulate increases in the Northern Annular Mode (NAM) and Southern Annular Mode (SAM) in every season by 2100, and no CMIP5 model simulates a significant decrease in either the NAM or SAM in any season. No significant increase in the NAM or North Atlantic Oscillation (NAO) is simulated in response to volcanic aerosol, and no significant NAM or NAO response to solar irradiance variations is simulated. The CMIP5 models simulate a significant negative SAM response to volcanic aerosol in MAM and JJA, and a significant positive SAM response to solar irradiance variations in MAM, JJA and DJF.

The relationship between interannual and long-term cloud feedbacks

DOE PAGES

Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.; ...

2015-12-11

The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual andmore » long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.

The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual andmore » long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.« less

1989 Intercomparison of radon progeny measurement methods and equipment in North America

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scofield, P.; George, A.; Tu, Keng.

1990-03-01

At the 1989 {sup 222}Rn progeny intercomparison held at the Environmental Measurements Laboratory (EML), July 10--14, 1989, grab sampling and integrating/continuous {sup 222}Rn progeny methods were evaluated. Sixteen facilities participated in this intercomparison. Twelve facilities used {sup 222}Rn progeny grab sampling methods, and nine facilities used integrating/continuous instruments. Eighty-eight percent of the participants reported grab sample {sup 222}Rn progeny concentrations that were within 20% of the EML reference values. Good agreement between participant and EML grab-sample potential alpha energy concentrations (PAECs) was observed; 92% of the participants had PAECs within 20% of the EML values. For the integrating/continuous PAEC valuesmore » determined with integrating/continuous monitors, 89% of the participants were within 20% of the EML reference values. 9 refs., 3 figs., 4 tabs.« less

Constraining the long-term climate reponse to stratospheric sulfate aerosols injection by the short-term volcanic climate response

NASA Astrophysics Data System (ADS)

Plazzotta, M.; Seferian, R.; Douville, H.; Kravitz, B.; Tilmes, S.; Tjiputra, J.

2016-12-01

Rising greenhouse gas emissions are leading to global warming and climate change, which will have multiple impacts on human society. Geoengineering methods like solar radiation management by stratospheric sulfate aerosols injection (SSA-SRM) aim at treating the symptoms of climate change by reducing the global temperature. Since a real-world testing cannot be implemented, Earth System Models (ESMs) are useful tools to assess the climate impacts of such geoengineering methods. However, coordinated simulations performed with the Geoengineering Model Intercomparison Project (GeoMIP) have shown that climate cooling in response to a continuous injection of 5Tg of SO2 per year under RCP45 future projection (the so-called G4 experiment) differs substantially between ESMs. Here, we employ a volcano analog approach to constrain the climate response in SSA-SRM geoengineering simulations across an ensemble of 10 ESMs. We identify an emergent relationship between the long-term cooling in responses to the mitigation of the clear-sky surface downwelling shortwave radiation (RSDSCS), and the short-term cooling related to the change in RSDSCS during the major tropical volcanic eruptions observed over the historical period (1850-2005). This relationship explains almost 80% of the multi-model spread. Combined with contemporary observations of the latest volcanic eruptions (satellite observations and model reanalyzes), this relationship provides a tight constraint on the climate impacts of SSA-SRM. We estimate that a continuous injection of SO2 aerosols into the stratosphere will reduce the global average temperature of continental land surface by 0.47 K per W m-2, impacting both hydrological and carbon cycles. Compared with the unconstrained ESMs ensemble (range from 0.32 to 0.92 K per W m-2 ), our estimate represents much higher confidence ways to assess the impacts of SSA-SRM on the climate while ruling the most extreme projections of the unconstrained ensemble extremely unlikely.

PFLOTRAN-RepoTREND Source Term Comparison Summary.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frederick, Jennifer M.

Code inter-comparison studies are useful exercises to verify and benchmark independently developed software to ensure proper function, especially when the software is used to model high-consequence systems which cannot be physically tested in a fully representative environment. This summary describes the results of the first portion of the code inter-comparison between PFLOTRAN and RepoTREND, which compares the radionuclide source term used in a typical performance assessment.

GLM Proxy Data Generation: Methods for Stroke/Pulse Level Inter-Comparison of Ground-Based Lightning Reference Networks

NASA Technical Reports Server (NTRS)

Cummins, Kenneth L.; Carey, Lawrence D.; Schultz, Christopher J.; Bateman, Monte G.; Cecil, Daniel J.; Rudlosky, Scott D.; Petersen, Walter Arthur; Blakeslee, Richard J.; Goodman, Steven J.

2011-01-01

In order to produce useful proxy data for the GOES-R Geostationary Lightning Mapper (GLM) in regions not covered by VLF lightning mapping systems, we intend to employ data produced by ground-based (regional or global) VLF/LF lightning detection networks. Before using these data in GLM Risk Reduction tasks, it is necessary to have a quantitative understanding of the performance of these networks, in terms of CG flash/stroke DE, cloud flash/pulse DE, location accuracy, and CLD/CG classification error. This information is being obtained through inter-comparison with LMAs and well-quantified VLF/LF lightning networks. One of our approaches is to compare "bulk" counting statistics on the spatial scale of convective cells, in order to both quantify relative performance and observe variations in cell-based temporal trends provided by each network. In addition, we are using microsecond-level stroke/pulse time correlation to facilitate detailed inter-comparisons at a more-fundamental level. The current development status of our ground-based inter-comparison and evaluation tools will be presented, and performance metrics will be discussed through a comparison of Vaisala s Global Lightning Dataset (GLD360) with the NLDN at locations within and outside the U.S.

GLM Proxy Data Generation: Methods for Stroke/Pulse Level Inter-comparison of Ground-based Lightning Reference Networks

NASA Astrophysics Data System (ADS)

Cummins, K. L.; Carey, L. D.; Schultz, C. J.; Bateman, M. G.; Cecil, D. J.; Rudlosky, S. D.; Petersen, W. A.; Blakeslee, R. J.; Goodman, S. J.

2011-12-01

In order to produce useful proxy data for the GOES-R Geostationary Lightning Mapper (GLM) in regions not covered by VLF lightning mapping systems, we intend to employ data produced by ground-based (regional or global) VLF/LF lightning detection networks. Before using these data in GLM Risk Reduction tasks, it is necessary to have a quantitative understanding of the performance of these networks, in terms of CG flash/stroke DE, cloud flash/pulse DE, location accuracy, and CLD/CG classification error. This information is being obtained through inter-comparison with LMAs and well-quantified VLF/LF lightning networks. One of our approaches is to compare "bulk" counting statistics on the spatial scale of convective cells, in order to both quantify relative performance and observe variations in cell-based temporal trends provided by each network. In addition, we are using microsecond-level stroke/pulse time correlation to facilitate detailed inter-comparisons at a more-fundamental level. The current development status of our ground-based inter-comparison and evaluation tools will be presented, and performance metrics will be discussed through a comparison of Vaisala's Global Lightning Dataset (GLD360) with the NLDN at locations within and outside the U.S.

Evaluation of Intercomparisons of Four Different Types of Model Simulating TWP-ICE

NASA Technical Reports Server (NTRS)

Petch, Jon; Hill, Adrian; Davies, Laura; Fridlind, Ann; Jakob, Christian; Lin, Yanluan; Xie, Shaoecheng; Zhu, Ping

2013-01-01

Four model intercomparisons were run and evaluated using the TWP-ICE field campaign, each involving different types of atmospheric model. Here we highlight what can be learnt from having single-column model (SCM), cloud-resolving model (CRM), global atmosphere model (GAM) and limited-area model (LAM) intercomparisons all based around the same field campaign. We also make recommendations for anyone planning further large multi-model intercomparisons to ensure they are of maximum value to the model development community. CRMs tended to match observations better than other model types, although there were exceptions such as outgoing long-wave radiation. All SCMs grew large temperature and moisture biases and performed worse than other model types for many diagnostics. The GAMs produced a delayed and significantly reduced peak in domain-average rain rate when compared to the observations. While it was shown that this was in part due to the analysis used to drive these models, the LAMs were also driven by this analysis and did not have the problem to the same extent. Based on differences between the models with parametrized convection (SCMs and GAMs) and those without (CRMs and LAMs), we speculate that that having explicit convection helps to constrain liquid water whereas the ice contents are controlled more by the representation of the microphysics.

1983 international intercomparison of nuclear accident dosimetry systems at Oak Ridge National Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swaja, R.E.; Greene, R.T.; Sims, C.S.

1985-04-01

An international intercomparison of nuclear accident dosimetry systems was conducted during September 12-16, 1983, at Oak Ridge National Laboratory (ORNL) using the Health Physics Research Reactor operated in the pulse mode to simulate criticality accidents. This study marked the twentieth in a series of annual accident dosimetry intercomparisons conducted at ORNL. Participants from ten organizations attended this intercomparison and measured neutron and gamma doses at area monitoring stations and on phantoms for three different shield conditions. Results of this study indicate that foil activation techniques are the most popular and accurate method of determining accident-level neutron doses at area monitoringmore » stations. For personnel monitoring, foil activation, blood sodium activation, and thermoluminescent (TL) methods are all capable of providing accurate dose estimates in a variety of radiation fields. All participants in this study used TLD's to determine gamma doses with very good results on the average. Chemical dosemeters were also shown to be capable of yielding accurate estimates of total neutron plus gamma doses in a variety of radiation fields. While 83% of all neutron measurements satisfied regulatory standards relative to reference values, only 39% of all gamma results satisfied corresponding guidelines for gamma measurements. These results indicate that continued improvement in accident dosimetry evaluation and measurement techniques is needed.« less

Airborne hygrometer calibration inter-comparison against a metrological water vapour standard

NASA Astrophysics Data System (ADS)

Smorgon, Denis; Boese, Norbert; Ebert, Volker

2014-05-01

Water vapour is the most important atmospheric greenhouse gas, which causes a major feedback to warming and other changes in the climate system. Knowledge of the distribution of water vapour and its climate induced changes is especially important in the upper troposphere and lower stratosphere (UT/LS) where vapour plays a critical role in atmospheric radiative balance, cirrus cloud formation, and photochemistry. But, our understanding of water in the UT/LS is limited by significant uncertainties in current UT/LS water measurements. One of the most comprehensive inter-comparison campaigns for airborne hygrometers, termed AQUAVIT (AV1) [1], took place in 2007 at the AIDA chamber at the Karlsruhe Institute of Technology (KIT) in Germany. AV1 was a well-defined, referred, blind inter-comparison of 22 airborne field instruments from 17 international research groups. One major metrological deficit of AV1, however, was, that no traceable reference instrument participated in the inter-comparison experiments and that the calibration procedures of the participating instruments were not monitored or interrogated. Consequently a follow-up inter-comparison was organized in April 2013, which for the first time also provides a traceable link to the international humidity scale. This AQUAVIT2 (AV2) campaign (details see: http://www.imk-aaf.kit.edu/aquavit/index.php/Main_Page) was again located at KIT/AIDA and organised by an international organizing committee including KIT, PTB, FZJ and others. Generally AV2 is divided in two parallel comparisons: 1) AV2-A uses the AIDA chamber for a simultaneous comparison of all instruments (incl. sampling and in-situ instruments) over a broad range of conditions characteristic for the UT/LS; 2) AV2-B, about which this paper is reporting, is a sequential comparison of selected hygrometers and (when possible) their reference calibration infrastructures by means of a chilled mirror hygrometer traced back to the primary National humidity standard of PTB and a validated, two-pressure generator acting as a highly stable and reproducible source of water vapour. The aim of AV2-B was to perform an absolute, metrological comparison of the field instruments/calibration infrastructures to the metrological humidity scale, and to collect essential information about methods and procedures used by the atmospheric community for instrument calibration and validation, in order to investigate e.g. the necessity and possible comparability advantage by a standardized calibration procedure. The work will give an overview over the concept of the AV2-B inter-comparison, the various general measurement and calibration principles, and discuss the outcome and consequences of the comparison effort. The AQUAVIT effort is linked to the EMRP project METEOMET (ENV07) and partially supported by the EMRP and ENV07. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. [1] H. Saathoff, C. Schiller, V. Ebert, D. W. Fahey, R.-S. Gao, O. Möhler, and the aquavit team, The AQUAVIT formal intercomparison of atmospheric water measurement methods, 5th General Assembly of the European Geosciences Union, 13-18 April 2008, Vienna, Austria Keywords: humidity, water vapour, inter-comparison, airborne instruments.

Interhemispheric Temperature Asymmetry in Historical Observations and Future Projections

NASA Astrophysics Data System (ADS)

Friedman, A. R.; Hwang, Y.; Chiang, J. C.; Frierson, D. M.

2013-12-01

The surface temperature contrast between the northern and southern hemispheres -- the interhemispheric temperature asymmetry (ITA) -- is an emerging indicator of global climate change, especially relevant to the latitude of the tropical rain bands. We investigate the ITA over historical observations and in Coupled Model Intercomparison Project phase 5 (CMIP5) historical simulations and future projections. We find that the uneven spatial impacts of greenhouse gas forcing cause amplified warming in the Arctic and northern landmasses, resulting in an increase of the ITA. However, anthropogenic sulfate aerosols, which are disproportionately emitted in the northern hemisphere, masked these effects on the ITA until around 1980. The implementation of air pollution regulations in North America and Europe combined with increased global emissions of greenhouse gases have resulted in a significant positive ITA trend since 1980. The CMIP5 historical multimodel ensembles simulate this positive ITA trend, though not its full magnitude. We explore how natural variability may account for some of the differences between the simulated and observed ITA. Future simulations project a substantial increase of the ITA over the twenty-first century, well outside its twentieth-century variability. This is largely in response to continued greenhouse gas emissions, though anthropogenic aerosol emissions are also important in some scenarios. We discuss the potential implications of this northern warming in causing a northward shift in tropical rainfall.

Response of wheat yield in Spain to large-scale patterns

NASA Astrophysics Data System (ADS)

Hernandez-Barrera, Sara; Rodriguez-Puebla, Concepcion

2016-04-01

Crops are vulnerable to extreme climate conditions as drought, heat stress and frost risk. In previous study we have quantified the influence of these climate conditions for winter wheat in Spain (Hernandez-Barrera et al. 2015). The climate extremes respond to large-scale atmospheric and oceanic patterns. Therefore, a question emerges in our investigation: How large-scale patterns affect wheat yield? Obtaining and understanding these relationships require different approaches. In this study, we first obtained the leading mode of observed wheat yield variability to characterize the common variability over different provinces in Spain. Then, the wheat variability is related to different modes of mean sea level pressure, jet stream and sea surface temperature by using Partial Least-Squares, which captures the relevant climate drivers accounting for variations in wheat yield from sowing to harvesting. We used the ERA-Interim reanalysis data and the Extended Reconstructed Sea Surface Temperature (SST) (ERSST v3b). The derived model provides insight about the teleconnections between wheat yield and atmospheric and oceanic circulations, which is considered to project the wheat yield trend under global warming using outputs of twelve climate models corresponding to the Coupled Models Intercomparison Project phase 5 (CMIP5). Hernandez-Barrera S., C. Rodríguez-Puebla and A.J. Challinor. Effects of diurnal temperature range and drought on wheat yield in Spain. Theoretical and Applied Climatology (submitted)

NDSC Lidar Intercomparisons and Validation: OPAL and MLO3 Campaigns in 1995

NASA Technical Reports Server (NTRS)

McDermid, Stuart; McGee, Thomas J.; Stuart, Daan P. J.

1996-01-01

The Network for the Detection of Stratospheric Change (NDSC) has developed and adopted a Validation Policy in order to ensure that the results submitted and stored in its archives are of a known, high quality. As a part of this validation policy, blind instrument intercomparisons are considered an essential element in the certification of NDSC instruments and a specific format for these campaigns has been recommended by the NDSC-Steering Committee.

The April 1992 and November 1992 radon intercomparisons at EML

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisenne, I.M.; George, A.C.; Perry, P.M.

1993-07-01

The Environmental Measurements Laboratory hosted two intercomparison exercises in Calendar Year 1992. Thirty-two groups, including US federal facilities, US Department of Energy`s Office of Health and Environmental Research contractors, national and state laboratories, and universities and foreign institutions, participated in these exercises. The majority of the participants` results were within {plus_minus}10% of the EML value at radon concentrations of 2075 and 1650 Bq m{sup {minus}3}.

The April 1994 and October 1994 radon intercomparisons at EML

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisenne, I.M.; George, A.C.; Perry, P.M.

1995-10-01

Quality assurance/quality control (QA/QC) are the backbone of many commercial and research processes and programs. QA/QC research tests the state of a functioning system, be it the production of manufactured goods or the ability to make accurate and precise measurements. The quality of the radon measurements in the US have been tested under controlled conditions in semi-annual radon gas intercomparison exercises sponsored by the Environmental Measurements Laboratory (EML) since 1981. The two Calendar Year 1994 radon gas intercomparison exercises were conducted in the EML exposure chamber. Thirty-two groups including US Federal facilities, USDOE contractors, national and state laboratories, universities andmore » foreign institutions participated in these exercises. The majority of the participant`s results were within {+-}10% of the EML value at radon concentrations of 570 and 945 Bq m{sup {minus}3}.« less

The global gridded crop model intercomparison: Data and modeling protocols for Phase 1 (v1.0)

DOE PAGES

Elliott, J.; Müller, C.; Deryng, D.; ...

2015-02-11

We present protocols and input data for Phase 1 of the Global Gridded Crop Model Intercomparison, a project of the Agricultural Model Intercomparison and Improvement Project (AgMIP). The project consist of global simulations of yields, phenologies, and many land-surface fluxes using 12–15 modeling groups for many crops, climate forcing data sets, and scenarios over the historical period from 1948 to 2012. The primary outcomes of the project include (1) a detailed comparison of the major differences and similarities among global models commonly used for large-scale climate impact assessment, (2) an evaluation of model and ensemble hindcasting skill, (3) quantification ofmore » key uncertainties from climate input data, model choice, and other sources, and (4) a multi-model analysis of the agricultural impacts of large-scale climate extremes from the historical record.« less

High Resolution Model Intercomparison Project (HighResMIP v1.0) for CMIP6

DOE PAGES

Haarsma, Reindert J.; Roberts, Malcolm J.; Vidale, Pier Luigi; ...

2016-11-22

Robust projections and predictions of climate variability and change, particularly at regional scales, rely on the driving processes being represented with fidelity in model simulations. The role of enhanced horizontal resolution in improved process representation in all components of the climate system is of growing interest, particularly as some recent simulations suggest both the possibility of significant changes in large-scale aspects of circulation as well as improvements in small-scale processes and extremes. However, such high-resolution global simulations at climate timescales, with resolutions of at least 50 km in the atmosphere and 0.25° in the ocean, have been performed at relativelymore » few research centres and generally without overall coordination, primarily due to their computational cost. Assessing the robustness of the response of simulated climate to model resolution requires a large multi-model ensemble using a coordinated set of experiments. The Coupled Model Intercomparison Project 6 (CMIP6) is the ideal framework within which to conduct such a study, due to the strong link to models being developed for the CMIP DECK experiments and other model intercomparison projects (MIPs). Increases in high-performance computing (HPC) resources, as well as the revised experimental design for CMIP6, now enable a detailed investigation of the impact of increased resolution up to synoptic weather scales on the simulated mean climate and its variability. The High Resolution Model Intercomparison Project (HighResMIP) presented in this paper applies, for the first time, a multi-model approach to the systematic investigation of the impact of horizontal resolution. A coordinated set of experiments has been designed to assess both a standard and an enhanced horizontal-resolution simulation in the atmosphere and ocean. The set of HighResMIP experiments is divided into three tiers consisting of atmosphere-only and coupled runs and spanning the period 1950–2050, with the possibility of extending to 2100, together with some additional targeted experiments. This paper describes the experimental set-up of HighResMIP, the analysis plan, the connection with the other CMIP6 endorsed MIPs, as well as the DECK and CMIP6 historical simulations. Lastly, HighResMIP thereby focuses on one of the CMIP6 broad questions, “what are the origins and consequences of systematic model biases?”, but we also discuss how it addresses the World Climate Research Program (WCRP) grand challenges.« less

FIRST EURADOS INTERCOMPARISON EXERCISE OF EYE LENS DOSEMETERS FOR MEDICAL APPLICATIONS.

PubMed

Clairand, I; Ginjaume, M; Vanhavere, F; Carinou, E; Daures, J; Denoziere, M; Silva, E H; Roig, M; Principi, S; Van Rycheghem, L

2016-09-01

In the context of the decrease in the eye lens dose limit for occupational exposure to 20 mSv per year stated by the recent revision of the European Basic Safety Standards Directive 2013/59/EURATOM, the European Radiation Dosimetry Group (EURADOS) has organised in 2014, for the first time, an intercomparison exercise for eye lens dosemeters. The main objective was to assess the capabilities of the passive eye lens dosemeters currently in use in Europe for occupational monitoring in medical fields. A total of 20 European individual monitoring services from 15 different countries have participated. The dosemeters provided by the participants were all composed of thermoluminescent detectors, of various types and designs. The irradiations were carried out with several photon fields chosen to cover the energy and angle ranges encountered in medical workplace. Participants were asked to report the doses in terms of Hp(3) using their routine protocol. The results provided by each participant were compared with the reference delivered doses. All the results were anonymously analysed. Results are globally satisfactory since, among the 20 participants, 17 were able to provide 90 % of their response in accordance with the ISO 14146 standard requirements. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Intermodel spread of the double-ITCZ bias in coupled GCMs tied to land surface temperature in AMIP GCMs

NASA Astrophysics Data System (ADS)

Zhou, Wenyu; Xie, Shang-Ping

2017-08-01

Global climate models (GCMs) have long suffered from biases of excessive tropical precipitation in the Southern Hemisphere (SH). The severity of the double-Intertropical Convergence Zone (ITCZ) bias, defined here as the interhemispheric difference in zonal mean tropical precipitation, varies strongly among models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) ensemble. Models with a more severe double-ITCZ bias feature warmer tropical sea surface temperature (SST) in the SH, coupled with weaker southeast trades. While previous studies focus on coupled ocean-atmosphere interactions, here we show that the intermodel spread in the severity of the double-ITCZ bias is closely related to land surface temperature biases, which can be further traced back to those in the Atmosphere Model Intercomparison Project (AMIP) simulations. By perturbing land temperature in models, we demonstrate that cooler land can indeed lead to a more severe double-ITCZ bias by inducing the above coupled SST-trade wind pattern in the tropics. The response to land temperature can be consistently explained from both the dynamic and energetic perspectives. Although this intermodel spread from the land temperature variation does not account for the ensemble model mean double-ITCZ bias, identifying the land temperature effect provides insights into simulating a realistic ITCZ for the right reasons.

The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Overview and Description of Models, Simulations and Climate Diagnostics

NASA Technical Reports Server (NTRS)

Lamarque, J.-F.; Shindell, D. T.; Naik, V.; Plummer, D.; Josse, B.; Righi, M.; Rumbold, S. T.; Schulz, M.; Skeie, R. B.; Strode, S.;

An intercomparison for NIRS and NYU passive thoron gas detectors at NYU.

PubMed

Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Chittaporn, Passaporn; Harley, Naomi H

2012-04-01

An intercomparison on thoron ((220)Rn) measurement was carried out between National Institute of Radiological Sciences, Japan (NIRS), and New York University School of Medicine, USA (NYU). The measurements of (220)Rn concentration at NIRS and NYU were performed by using the scintillation cell method and the two-filter method, respectively, as the standard measurement method. Three types of alpha track detectors based on passive radon ((222)Rn)-(220)Rn discriminative measurement technique were used: Raduet and Radopot detectors were used at NIRS, and four-leaf detectors were used at NYU. In this study, the authors evaluated (220)Rn concentration variation in terms of run for exposure, measurement method, and exposure chamber. The detectors were exposed to (220)Rn gas with approximately 15 kBq m(-3) during the period from 0.75 to 3 d. As a result, the variation of each measurement method among these exposure runs was comparable to or less than that for the two-filter method. Agreement between the standard measurement methods of NIRS and NYU was observed to be about 10%, as is the case with the passive detectors. The Raduet detector showed a large variation in the detection response between the NIRS and NYU chambers, which could be related to different traceability.

The AgMIP Coordinated Climate-Crop Modeling Project (C3MP): Methods and Protocols

NASA Technical Reports Server (NTRS)

Shukla, Sonali P.; Ruane, Alexander Clark

2014-01-01

Climate change is expected to alter a multitude of factors important to agricultural systems, including pests, diseases, weeds, extreme climate events, water resources, soil degradation, and socio-economic pressures. Changes to carbon dioxide concentration ([CO2]), temperature, and water (CTW) will be the primary drivers of change in crop growth and agricultural systems. Therefore, establishing the CTW-change sensitivity of crop yields is an urgent research need and warrants diverse methods of investigation. Crop models provide a biophysical, process-based tool to investigate crop responses across varying environmental conditions and farm management techniques, and have been applied in climate impact assessment by using a variety of methods (White et al., 2011, and references therein). However, there is a significant amount of divergence between various crop models' responses to CTW changes (Rotter et al., 2011). While the application of a site-based crop model is relatively simple, the coordination of such agricultural impact assessments on larger scales requires consistent and timely contributions from a large number of crop modelers, each time a new global climate model (GCM) scenario or downscaling technique is created. A coordinated, global effort to rapidly examine CTW sensitivity across multiple crops, crop models, and sites is needed to aid model development and enhance the assessment of climate impacts (Deser et al., 2012). To fulfill this need, the Coordinated Climate-Crop Modeling Project (C3MP) (Ruane et al., 2014) was initiated within the Agricultural Model Intercomparison and Improvement Project (AgMIP; Rosenzweig et al., 2013). The submitted results from C3MP Phase 1 (February 15, 2013-December 31, 2013) are currently being analyzed. This chapter serves to present and update the C3MP protocols, discuss the initial participation and general findings, comment on needed adjustments, and describe continued and future development. AgMIP aims to improve substantially the climate, crop, and economic simulation tools that are used to characterize the agricultural sector, to assess future world food security under changing climate conditions, and to enhance adaptation capacity both globally and regionally. To understand better and improve the modeled crop responses, AgMIP has conducted detailed crop model intercomparisons at closely observed field sites for wheat (Asseng et al., 2013), rice (Li et al., in review), maize (Bassu et al., 2014), and sugarcane (Singels et al., 2013). A coordinated modeling exercise was one of the original motivations for AgMIP, and C3MP provides rapid estimation of crop responses to CO2, water, and temperature (CTW) changes, adding dimension and insight into the crop model intercomparisons, while facilitating interactions within the global community of modelers. C3MP also contributes a fast-track, multi-model climate sensitivity assessment for the AgMIP climate and crop modeling teams on Research Track 2 (Fig. 1), which seeks to understand the impact of projected climatic changes on crop production and food security (Rosenzweig et al., 2013; Ruane et al., 2014).

Inter-comparison between AIRS and IASI through Retrieved Parameters

NASA Technical Reports Server (NTRS)

Zhou, Daniel K.; Larar, Allen M.; Smith, William L.; Taylor, Jonathan P.; Schluessel, Peter; Strow, L. Larrabee; Mango, Steve

2008-01-01

A State-of-the-art retrieval algorithm dealing with all-weather conditions has been applied to satellite/aircraft instruments retrieving cloud/surface and atmospheric conditions. High quality retrievals have been achieved from IASI data. Surface, cloud, and atmospheric structure and variation are well captured by IASI measurements and/or retrievals. The same retrieval algorithm is also applied to AIRS for retrieval inter-comparison. Both AIRS and IASI have a similar FOV size but AIRS has a higher horizontal resolution. AIRS data can be interpolated to IASI horizontal resolution for inter-comparison at the same geophysical locations, however a temporal variation between AIRS and IASI observations need to be considered. JAIVEx has employed aircraft to obtain the atmospheric variation filling the temporal gap between two satellites. First results show that both AIRS and IASI have a very similar vertical resolving power, atmospheric conditions are well captured by both instruments, and radiances are well calibrated. AIRS data shown in retrievals (e.g., surface emissivity and moisture) have a relatively higher noise level. Since the this type of retrieval is very sensitive to its radiance quality, retrieval products inter-comparison is an effective way to identify/compare their radiance quality, in terms of a combination of spectral resolution and noise level, and to assess instrument performance. Additional validation analyses are needed to provide more-definitive conclusions.

Advection of sulfur dioxide over the western Atlantic Ocean during CITE 3

NASA Technical Reports Server (NTRS)

Thornton, D. C.; Bandy, A. R.; Beltz, N.; Driedger, A. R., III; Ferek, R.

1993-01-01

During the NASA Chemical Instrumentation Test and Evaluation 3 sulfur intercomparison over the western Atlantic Ocean, five techniques for the determination of sulfur dioxide were evaluated. The response times of the techniques varied from 3 to 30 min. Based on the ensemble of measurements reported, it was clear that advection of SO2 from the North American continent occurred in the boundary layer (altitude less than 1 km) with only one exception. The vertical distribution of SO2 above the boundary layer for the northern and southern Atlantic Ocean was remarkably similar duing this experiment.

New cetacean ΔR values for Arctic North America and their implications for marine-mammal-based palaeoenvironmental reconstructions

NASA Astrophysics Data System (ADS)

Furze, Mark F. A.; Pieńkowski, Anna J.; Coulthard, Roy D.

2014-05-01

Radiocarbon-dated marine mammal remains from emergent Arctic coastlines have frequently been used to reconstruct Holocene sea-ice histories. The use of such reconstructions has hitherto been complicated by uncertain marine reservoir corrections precluding meaningful intercomparisons with data reported in calibrated or sidereal years. Based on an exhaustive compilation of previously published marine mammal radiocarbon dates (both live-harvested materials and subfossils) from the Canadian Arctic Archipelago (CAA), new, statistically-derived δ13C and ΔR values are provided. Average δ13C values are: -16.1 ± 1.1‰ (bone collagen; n = 193) for bowhead (Balaena mysticetus); -14.4 ± 0.5‰ (n = 44; dentine) for beluga (Delphinapterus leucas); -14.8 ± 1.9‰ (teeth and tusks; n = 18) and -18.0 ± 4.7‰ (n = 9; bone collagen) for walrus (Odobenus rosmarus). ΔR values are 170 ± 95 14C years for bowhead (n = 23) and 240 ± 60 14C years for beluga (n = 12). Scarce data preclude calculation of meaningful, statistically robust walrus ΔR. Using the new ΔR values, an expanded and revised database of calibrated bowhead dates (651 dates; many used in previous CAA sea-ice reconstructions) shows pronounced late Quaternary spatio-temporal fluctuations in bone abundance. Though broadly resembling earlier bowhead subfossil frequency data, analysis of the new expanded database suggests early- and mid-Holocene increases in whale abundance to be of longer duration and lower amplitude than previously considered. A more even and persistent spread of infrequent low-abundance remains during “whale free” intervals is also seen. The dominance of three eastern regions (Prince Regent Inlet & Gulf of Boothia; Admiralty Inlet; Berlinguet Inlet/Bernier Bay) in the CAA data, collectively contributing up to 88% of all subfossil remains in the mid-Holocene, is notable. An analysis of calibrated regional sea-level index points suggests that severance of the Admiralty Inlet-Gulf of Boothia marine channel due to isostatically-driven regression may have played a significant role in enhanced whale mortality during this interval. Comparisons between the newly calibrated bowhead data and other regional sea-ice proxy data further highlight spatial and temporal discrepancies, potentially due to regional asynchronicities and variable sensitivities in proxy response to climate and oceanographic forcing. However, the limited number of deglacial-postglacial marine records continues to hamper extensive intercomparisons between marine mammal and other proxy datasets. Nevertheless, an examination of assumptions inherent in linking bowhead subfossil frequencies, population densities, and sea-ice thickness and distribution, shows that such relationships are highly complex. Factors such as broad sea-ice preferences, variable mortality rates and causes, long distance carcass transport, variable coastline and basin/channel geometries, and changing emergence rates all complicate the correlation of whale bone abundance to sea-ice histories.

Robust impact of coupled stratospheric ozone chemistry on the response of the Austral circulation to increased greenhouse gases

NASA Astrophysics Data System (ADS)

Chiodo, G.; Polvani, L. M.

2016-12-01

Due to computational constraints, interactive stratospheric chemistry is commonly neglected in most GCMs participating in inter-comparison projects. The impact of this simplification on the modeled response to external forcings remains largely unexplored. In this work, we examine the impact of the stratospheric chemistry coupling on the SH circulation response to an abrupt quadrupling of CO2. We accomplish this with a version of the Whole Atmosphere Community Climate (WACCM) model, which allows coupling and de-coupling stratospheric chemistry, without altering any other physical parameterization. We find that the chemistry coupling in WACCM significantly reduces (by about 20%) the response of both eddy-driven mid-latitude jet and the Hadley Cell strength, without altering the surface temperature response. This behavior is linked to the representation of stratospheric ozone, and its effects on the meridional temperature gradient at the extratropical tropopause. Our results imply that neglecting stratospheric ozone chemistry results in a potential overestimation of the circulation response to GHGs. Hence, stratospheric ozone chemistry produces a substantial negative feedback on the response of the atmospheric circulation to increased greenhouse gases.

ACIX: Atmospheric Correction Inter-comparison Exercise

NASA Astrophysics Data System (ADS)

Doxani, Georgia; Gascon, Ferran; Vermote, Éric; Roger, Jean-Claude

2017-04-01

The free and open data access policy to Sentinel-2 (S-2) and Landsat-8 (L-8) satellite imagery has stimulated the development of atmospheric correction (AC) processors for generating Bottom-of-Atmosphere (BOA) products. Several entities have started to generate (or plan to generate in the short term) BOA reflectance products at global scale for S-2 and L-8 missions. To this end, the European Space Agency (ESA) and NASA are organizing an exercise on AC processors inter-comparison. The results of the exercise are expected to point out the strengths and weaknesses, as well as communalities and discrepancies of various AC processors, in order to suggest and define ways for their further improvement. In particular, 13 atmospheric processors from five different countries participate in ACIX with the aim to inter-compare their performance when applied to L-8 and S-2 data. A protocol describing the inter-comparison process and the test dataset, which is based on the AERONET sites, will be presented. The protocol has been defined according to what was agreed among the participants during the 1st ACIX workshop held in June 2016. It includes the comparison of aerosol optical thickness and water vapour products of the processors with the AERONET measurements. Moreover, concerning the surface reflectances, the protocol describes the inter-comparison among the processors, as well as the comparison with the MODIS surface reflectance and with a reference surface reflectance product. Such a reference product will be obtained using the AERONET characterization of the aerosol (size distribution and refractive indices) and an accurate radiative transfer code. The inter-comparison outcomes will be presented and discussed among the participants in the 2nd ACIX workshop, which will be held on 11-12 April 2017 (ESRIN/ESA). The proposed presentation is an opportunity for the user community to be informed for the first time about the ACIX results and conclusions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kooperman, Gabriel J.; Chen, Yang; Hoffman, Forrest M.

Understanding how anthropogenic CO 2 emissions will influence future precipitation is critical for sustainably managing ecosystems, particularly for drought-sensitive tropical forests. Although tropical precipitation change remains uncertain, nearly all models from the Coupled Model Intercomparison Project Phase 5 predict a strengthening zonal precipitation asymmetry by 2100, with relative increases over Asian and African tropical forests and decreases over South American forests. Here we show that the plant physiological response to increasing CO 2 is a primary mechanism responsible for this pattern. Applying a simulation design in the Community Earth System Model in which CO 2 increases are isolated over individualmore » continents, we demonstrate that different circulation, moisture and stability changes arise over each continent due to declines in stomatal conductance and transpiration. The sum of local atmospheric responses over individual continents explains the pan-tropical precipitation asymmetry. Our analysis suggests that South American forests may be more vulnerable to rising CO 2 than Asian or African forests.« less

ATHLI16: the ATHens Lidar Intercomparison campaign

NASA Astrophysics Data System (ADS)

Amodeo, Aldo; D'Amico, Giuseppe; Giunta, Aldo; Papagiannopoulos, Nikolaos; Papayannis, Alex; Argyrouli, Athina; Mylonaki, Maria; Tsaknakis, Georgios; Kokkalis, Panos; Soupiona, Ourania; Tzanis, Chris

2018-04-01

The results of the ATHLI16 (ATHens Lidar Intercomparison) campaign, held in Athens from 26/09 to 07/10 2016 are presented. The campaign was performed within the Lidar Calibration Centre activities (EU H2020 ACTRIS-2 project) to assess the performance of the EOLE lidar system (NTUA, Athens, Greece), operating within EARLINET, by comparing against the EARLINET reference lidar system MUSA (CNR-IMAA, Potenza, Italy). For both lidars only products retrieved by the EARLINET Single Calculus Chain have been compared.

Intercomparison of methods for coincidence summing corrections in gamma-ray spectrometry--part II (volume sources).

PubMed

Lépy, M-C; Altzitzoglou, T; Anagnostakis, M J; Capogni, M; Ceccatelli, A; De Felice, P; Djurasevic, M; Dryak, P; Fazio, A; Ferreux, L; Giampaoli, A; Han, J B; Hurtado, S; Kandic, A; Kanisch, G; Karfopoulos, K L; Klemola, S; Kovar, P; Laubenstein, M; Lee, J H; Lee, J M; Lee, K B; Pierre, S; Carvalhal, G; Sima, O; Tao, Chau Van; Thanh, Tran Thien; Vidmar, T; Vukanac, I; Yang, M J

2012-09-01

The second part of an intercomparison of the coincidence summing correction methods is presented. This exercise concerned three volume sources, filled with liquid radioactive solution. The same experimental spectra, decay scheme and photon emission intensities were used by all the participants. The results were expressed as coincidence summing corrective factors for several energies of (152)Eu and (134)Cs, and different source-to-detector distances. They are presented and discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

VLBI Digital-Backend Intercomparison Test Report

NASA Technical Reports Server (NTRS)

Whitney, Alan; Beaudoin, Christopher; Cappallo, Roger; Niell, Arthur; Petrachenko, Bill; Ruszczyk, Chester A.; Titus, Mike

2013-01-01

Issues related to digital-backend (DBE) systems can be difficult to evaluate in either local tests or actual VLBI experiments. The 2nd DBE intercomparison workshop at Haystack Observatory on 25-26 October 2012 provided a forum to explicitly address validation and interoperability issues among independent global developers of DBE equipment. This special report discusses the workshop. It identifies DBE systems that were tested at the workshop, describes the test objectives and procedures, and reports and discusses the results of the testing.

The August 1988 and June 1989 radon intercomparisons at EML (Environmental Measurements Laboratory)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisenne, I.M.; George, A.C.; Keller, H.W.

1990-06-01

The Environmental Measurements Laboratory hosted the fifteenth and sixteenth radon intercomparison exercises in August 1988 and June 1989. Forty-five groups including US Federal facilities, USDOE Office of Health and Environmental Research contractors, national and state laboratories and foreign institutions participated in these exercises. The results show that the majority of the participants' results were within {plus minus} of the EML value at radon concentrations of 220 and 890 Bq m{sup {minus}3}. 10 refs., 4 figs., 9 tabs.

Preliminary results of an intercomparison of total ozone spectrophotometers

NASA Technical Reports Server (NTRS)

Parsons, C. L.; Gerlach, J. C.; Williams, M. E.; Kerr, J. B.

1981-01-01

Preliminary results from an intercomparison of five total ozone spectrophotometers are presented. These are the Dobson spectrophotometer, the USSR M-83 ozonometer, the Canterbury filter photometer, the SenTran Company filter photometer, and the Brewer grating spectrophotometer. The pertinent characteristics of each are described, and conclusions are drawn about the agreement of each instrument's measurements with the Dobson's values over a time period of nearly one year. A discussion of the importance of calibration and long-term stability and reliability is included.

Carbon-Temperature-Water Change Analysis for Peanut Production Under Climate Change: A Prototype for the AgMIP Coordinated Climate-Crop Modeling Project (C3MP)

NASA Technical Reports Server (NTRS)

Ruane, Alex C.; McDermid, Sonali; Rosenzweig, Cynthia; Baigorria, Guillermo A.; Jones, James W.; Romero, Consuelo C.; Cecil, L. DeWayne

2014-01-01

Climate change is projected to push the limits of cropping systems and has the potential to disrupt the agricultural sector from local to global scales. This article introduces the Coordinated Climate-Crop Modeling Project (C3MP), an initiative of the Agricultural Model Intercomparison and Improvement Project (AgMIP) to engage a global network of crop modelers to explore the impacts of climate change via an investigation of crop responses to changes in carbon dioxide concentration ([CO2]), temperature, and water. As a demonstration of the C3MP protocols and enabled analyses, we apply the Decision Support System for Agrotechnology Transfer (DSSAT) CROPGRO-Peanut crop model for Henry County, Alabama, to evaluate responses to the range of plausible [CO2], temperature changes, and precipitation changes projected by climate models out to the end of the 21st century. These sensitivity tests are used to derive crop model emulators that estimate changes in mean yield and the coefficient of variation for seasonal yields across a broad range of climate conditions, reproducing mean yields from sensitivity test simulations with deviations of ca. 2% for rain-fed conditions. We apply these statistical emulators to investigate how peanuts respond to projections from various global climate models, time periods, and emissions scenarios, finding a robust projection of modest (<10%) median yield losses in the middle of the 21st century accelerating to more severe (>20%) losses and larger uncertainty at the end of the century under the more severe representative concentration pathway (RCP8.5). This projection is not substantially altered by the selection of the AgMERRA global gridded climate dataset rather than the local historical observations, differences between the Third and Fifth Coupled Model Intercomparison Project (CMIP3 and CMIP5), or the use of the delta method of climate impacts analysis rather than the C3MP impacts response surface and emulator approach.

Climatic effects of large-scale deforestation in Earth System Models

NASA Astrophysics Data System (ADS)

Brovkin, V.; Boysen, L.; Pongratz, J.

2017-12-01

Processes in terrestrial ecosystems, to a large extent, are controlled by climate and CO2 concentration. In turn, geographical distribution of vegetation cover strongly affects heat, moisture, and momentum fluxes between land surface and atmosphere (biogeophysical effects). Anthropogenic land use and land cover changes (LULCC) are now included into Earth System Models (ESMs) in the form of historical and hypothetical future scenarios as a forcing in the Coupled Model Intercomparison project, phase 6 (CMIP6). A propagation of climatic effects from land to the ocean in ESMs allows to investigate a global climate response to LULCC in addition to analysis of local effects over deforested land. One complication in the analysis of global climatic effects of historical and future LULCC scenarios is their relatively small amplitude. To increase the signal-to-noise ratio, the Land Use Model Intercomparison Project (LUMIP) suggested an idealized deforestation simulation following a prototype of 1%-CO2 increase experiment commonly used in CMIPs. The idealized experiment allows to investigate - in a harmonized way across models - a response of land surface biophysics and climate to a large-scale deforestation of 20 million km2 distributed over the most forested parts of globe. The forest is removed linearly over a period of 50 years, with an additional 30 years with no specified change in forest cover. Boundary conditions such as CO2 concentration and other forcings are kept at the pre-industrial level. We will present results of idealized deforestation experiments and other sensitivity runs with the CMIP6-version of MPI-ESM, which will be part of the later multi-model comparison. A special focus will be put on less well investigated aspects of LULCC that the idealized setup is particularly well suited for studying, such as non-linearities of the model response to the deforestation forcing and detectability of the signal over time.

Maintaining High Quality Data and Consistency Across a Diverse Flux Network: The Ameriflux QA/QC Technical Team

NASA Astrophysics Data System (ADS)

Chan, S.; Billesbach, D. P.; Hanson, C. V.; Biraud, S.

2014-12-01

The AmeriFlux quality assurance and quality control (QA/QC) technical team conducts short term (<2 weeks) intercomparisons using a portable eddy covariance system (PECS) to maintain high quality data observations and data consistency across the AmeriFlux network (http://ameriflux.lbl.gov/). Site intercomparisons identify discrepancies between the in situ and portable measurements and calculated fluxes. Findings are jointly discussed by the site staff and the QA/QC team to improve in the situ observations. Despite the relatively short duration of an individual site intercomparison, the accumulated record of all site visits (numbering over 100 since 2002) is a unique dataset. The ability to deploy redundant sensors provides a rare opportunity to identify, quantify, and understand uncertainties in eddy covariance and ancillary measurements. We present a few specific case studies from QA/QC site visits to highlight and share new and relevant findings related to eddy covariance instrumentation and operation.

The ENEA criticality accident dosimetry system: a contribution to the 2002 international intercomparison at the SILENE reactor.

PubMed

Gualdrini, G; Bedogni, R; Fantuzzi, E; Mariotti, F

2004-01-01

The present paper summarises the activity carried out at the ENEA Radiation Protection Institute for updating the methodologies employed for the evaluation of the neutron and photon dose to the exposed workers in case of a criticality accident, in the framework of the 'International Intercomparison of Criticality Accident Dosimetry Systems' (Silène reactor, IRSN-CEA-Valduc June 2002). The evaluation of the neutron spectra and the neutron dosimetric quantities relies on activation detectors and on unfolding algorithms. Thermoluminescent detectors are employed for the gamma dose measurement. The work is aimed at accurately characterising the measurement system and, at the same time, testing the algorithms. Useful spectral information were included, based on Monte Carlo simulations, to take into account the potential accident scenarios of practical interest. All along this exercise intercomparison a particular attention was devoted to the 'traceability' of all the experimental and computational parameters and therefore, aimed at an easy treatment by the user.

An overview of sensor calibration inter-comparison and applications

USGS Publications Warehouse

Xiong, Xiaoxiong; Cao, Changyong; Chander, Gyanesh

2010-01-01

Long-term climate data records (CDR) are often constructed using observations made by multiple Earth observing sensors over a broad range of spectra and a large scale in both time and space. These sensors can be of the same or different types operated on the same or different platforms. They can be developed and built with different technologies and are likely operated over different time spans. It has been known that the uncertainty of climate models and data records depends not only on the calibration quality (accuracy and stability) of individual sensors, but also on their calibration consistency across instruments and platforms. Therefore, sensor calibration inter-comparison and validation have become increasingly demanding and will continue to play an important role for a better understanding of the science product quality. This paper provides an overview of different methodologies, which have been successfully applied for sensor calibration inter-comparison. Specific examples using different sensors, including MODIS, AVHRR, and ETM+, are presented to illustrate the implementation of these methodologies.

BIPM project: Intercomparison of water triple-point cells

NASA Astrophysics Data System (ADS)

Chattle, M. V.; Butler, J.

1994-12-01

The paper presents the results of an intercomparison between 3 triple point of water cells circulated by the Bureau International des Poids et Measures (BIPM), and a cell which is one of those used as a reference cell at the National Physical Laboratory (NPL). All 4 cells were prepared, stored and measured in the manner normally adopted at NPL. The results of the intercomparison show that over the course of about 6 weeks the temperatures of the 3 circulated cells generally agreed within 0.20 mK, with a maximum difference of 0.27(7) mK. Over the same period, the total variations of temperature measured in the 3 individual cells were 0.04 mK, 0.08 mK and 0.18 mK, respectively; the NPL cell varied by 0.10 mK. Gallium point measurements made over a similar period confirmed that these differences were partly due to small drifts in the thermometer resistance or in the measuring system.

FACE-IT. A Science Gateway for Food Security Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montella, Raffaele; Kelly, David; Xiong, Wei

Progress in sustainability science is hindered by challenges in creating and managing complex data acquisition, processing, simulation, post-processing, and intercomparison pipelines. To address these challenges, we developed the Framework to Advance Climate, Economic, and Impact Investigations with Information Technology (FACE-IT) for crop and climate impact assessments. This integrated data processing and simulation framework enables data ingest from geospatial archives; data regridding, aggregation, and other processing prior to simulation; large-scale climate impact simulations with agricultural and other models, leveraging high-performance and cloud computing; and post-processing to produce aggregated yields and ensemble variables needed for statistics, for model intercomparison, and to connectmore » biophysical models to global and regional economic models. FACE-IT leverages the capabilities of the Globus Galaxies platform to enable the capture of workflows and outputs in well-defined, reusable, and comparable forms. We describe FACE-IT and applications within the Agricultural Model Intercomparison and Improvement Project and the Center for Robust Decision-making on Climate and Energy Policy.« less

Forest response to rising CO 2 drives zonally asymmetric rainfall change over tropical land

DOE PAGES

Kooperman, Gabriel J.; Chen, Yang; Hoffman, Forrest M.; ...

2018-04-27

Understanding how anthropogenic CO 2 emissions will influence future precipitation is critical for sustainably managing ecosystems, particularly for drought-sensitive tropical forests. Although tropical precipitation change remains uncertain, nearly all models from the Coupled Model Intercomparison Project Phase 5 predict a strengthening zonal precipitation asymmetry by 2100, with relative increases over Asian and African tropical forests and decreases over South American forests. Here we show that the plant physiological response to increasing CO 2 is a primary mechanism responsible for this pattern. Applying a simulation design in the Community Earth System Model in which CO 2 increases are isolated over individualmore » continents, we demonstrate that different circulation, moisture and stability changes arise over each continent due to declines in stomatal conductance and transpiration. The sum of local atmospheric responses over individual continents explains the pan-tropical precipitation asymmetry. Our analysis suggests that South American forests may be more vulnerable to rising CO 2 than Asian or African forests.« less

Forest response to rising CO2 drives zonally asymmetric rainfall change over tropical land

NASA Astrophysics Data System (ADS)

Kooperman, Gabriel J.; Chen, Yang; Hoffman, Forrest M.; Koven, Charles D.; Lindsay, Keith; Pritchard, Michael S.; Swann, Abigail L. S.; Randerson, James T.

2018-05-01

Understanding how anthropogenic CO2 emissions will influence future precipitation is critical for sustainably managing ecosystems, particularly for drought-sensitive tropical forests. Although tropical precipitation change remains uncertain, nearly all models from the Coupled Model Intercomparison Project Phase 5 predict a strengthening zonal precipitation asymmetry by 2100, with relative increases over Asian and African tropical forests and decreases over South American forests. Here we show that the plant physiological response to increasing CO2 is a primary mechanism responsible for this pattern. Applying a simulation design in the Community Earth System Model in which CO2 increases are isolated over individual continents, we demonstrate that different circulation, moisture and stability changes arise over each continent due to declines in stomatal conductance and transpiration. The sum of local atmospheric responses over individual continents explains the pan-tropical precipitation asymmetry. Our analysis suggests that South American forests may be more vulnerable to rising CO2 than Asian or African forests.

Tropical precipitation extremes: Response to SST-induced warming in aquaplanet simulations

NASA Astrophysics Data System (ADS)

Bhattacharya, Ritthik; Bordoni, Simona; Teixeira, João.

2017-04-01

Scaling of tropical precipitation extremes in response to warming is studied in aquaplanet experiments using the global Weather Research and Forecasting (WRF) model. We show how the scaling of precipitation extremes is highly sensitive to spatial and temporal averaging: while instantaneous grid point extreme precipitation scales more strongly than the percentage increase (˜7% K-1) predicted by the Clausius-Clapeyron (CC) relationship, extremes for zonally and temporally averaged precipitation follow a slight sub-CC scaling, in agreement with results from Climate Model Intercomparison Project (CMIP) models. The scaling depends crucially on the employed convection parameterization. This is particularly true when grid point instantaneous extremes are considered. These results highlight how understanding the response of precipitation extremes to warming requires consideration of dynamic changes in addition to the thermodynamic response. Changes in grid-scale precipitation, unlike those in convective-scale precipitation, scale linearly with the resolved flow. Hence, dynamic changes include changes in both large-scale and convective-scale motions.

Climate and carbon cycle dynamics in a CESM simulation from 850-2100 CE

NASA Astrophysics Data System (ADS)

Lehner, F.; Joos, F.; Raible, C. C.; Mignot, J.; Born, A.; Keller, K. M.; Stocker, T. F.

2015-02-01

Under the protocols of the Paleoclimate and Coupled Modelling Intercomparison Projects a number of simulations were produced that provide a range of potential climate evolutions from the last millennium to the end of the current century. Here, we present the first simulation with the Community Earth System Model (CESM), which includes an interactive carbon cycle, that continuously covers the last millennium, the historical period, and the twenty-first century. Besides state-of-the-art forcing reconstructions, we apply a modified reconstruction of total solar irradiance to shed light on the issue of forcing uncertainty in the context of the last millennium. Nevertheless, we find that structural uncertainties between different models can still dominate over forcing uncertainty for quantities such as hemispheric temperatures or the land and ocean carbon cycle response. Comparing with other model simulations we find forced decadal-scale variability to occur mainly after volcanic eruptions, while during other periods internal variability masks potentially forced signals and calls for larger ensembles in paleoclimate modeling studies. At the same time, we fail to attribute millennial temperature trends to orbital forcing, as has been suggested recently. The climate-carbon cycle sensitivity in CESM during the last millennium is estimated to be about 1.3 ppm °C-1. However, the dependence of this sensitivity on the exact time period and scale illustrates the prevailing challenge of deriving robust constrains on this quantity from paleoclimate proxies. In particular, the response of the land carbon cycle to volcanic forcing shows fundamental differences between different models. In CESM the tropical land dictates the response to volcanoes with a distinct behavior for large and moderate eruptions. Under anthropogenic emissions, global land and ocean carbon uptake rates emerge from the envelope of interannual natural variability as simulated for the last millennium by about year 1947 and 1877, respectively.

Building a statistical emulator for prediction of crop yield response to climate change: a global gridded panel data set approach

NASA Astrophysics Data System (ADS)

Mistry, Malcolm; De Cian, Enrica; Wing, Ian Sue

2015-04-01

There is widespread concern that trends and variability in weather induced by climate change will detrimentally affect global agricultural productivity and food supplies. Reliable quantification of the risks of negative impacts at regional and global scales is a critical research need, which has so far been met by forcing state-of-the-art global gridded crop models with outputs of global climate model (GCM) simulations in exercises such as the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP)-Fastrack. Notwithstanding such progress, it remains challenging to use these simulation-based projections to assess agricultural risk because their gridded fields of crop yields are fundamentally denominated as discrete combinations of warming scenarios, GCMs and crop models, and not as model-specific or model-averaged yield response functions of meteorological shifts, which may have their own independent probability of occurrence. By contrast, the empirical climate economics literature has adeptly represented agricultural responses to meteorological variables as reduced-form statistical response surfaces which identify the crop productivity impacts of additional exposure to different intervals of temperature and precipitation [cf Schlenker and Roberts, 2009]. This raises several important questions: (1) what do the equivalent reduced-form statistical response surfaces look like for crop model outputs, (2) do they exhibit systematic variation over space (e.g., crop suitability zones) or across crop models with different characteristics, (3) how do they compare to estimates based on historical observations, and (4) what are the implications for the characterization of climate risks? We address these questions by estimating statistical yield response functions for four major crops (maize, rice, wheat and soybeans) over the historical period (1971-2004) as well as future climate change scenarios (2005-2099) using ISIMIP-Fastrack data for five GCMs and seven crop models under rain-fed and irrigated management regimes. Our approach, which is patterned after Lobell and Burke [2010], is a novel application of cross-section/time-series statistical techniques from the climate economics literature to large, high-dimension, multi-model datasets, and holds considerable promise as a diagnostic methodology to elucidate uncertainties in the processes simulated by crop models, and to support the development of climate impact intercomparison exercises.

The Radiative Forcing Model Intercomparison Project (RFMIP): Experimental protocol for CMIP6

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pincus, Robert; Forster, Piers M.; Stevens, Bjorn

The phrasing of the first of three questions motivating CMIP6 – “How does the Earth system respond to forcing?” – suggests that forcing is always well-known, yet the radiative forcing to which this question refers has historically been uncertain in coordinated experiments even as understanding of how best to infer radiative forcing has evolved. The Radiative Forcing Model Intercomparison Project (RFMIP) endorsed by CMIP6 seeks to provide a foundation for answering the question through three related activities: (i) accurate characterization of the effective radiative forcing relative to a near-preindustrial baseline and careful diagnosis of the components of this forcing; (ii) assessment ofmore » the absolute accuracy of clear-sky radiative transfer parameterizations against reference models on the global scales relevant for climate modeling; and (iii) identification of robust model responses to tightly specified aerosol radiative forcing from 1850 to present. Complete characterization of effective radiative forcing can be accomplished with 180 years (Tier 1) of atmosphere-only simulation using a sea-surface temperature and sea ice concentration climatology derived from the host model's preindustrial control simulation. Assessment of parameterization error requires trivial amounts of computation but the development of small amounts of infrastructure: new, spectrally detailed diagnostic output requested as two snapshots at present-day and preindustrial conditions, and results from the model's radiation code applied to specified atmospheric conditions. In conclusion, the search for robust responses to aerosol changes relies on the CMIP6 specification of anthropogenic aerosol properties; models using this specification can contribute to RFMIP with no additional simulation, while those using a full aerosol model are requested to perform at least one and up to four 165-year coupled ocean–atmosphere simulations at Tier 1.« less

The Radiative Forcing Model Intercomparison Project (RFMIP): Experimental protocol for CMIP6

DOE PAGES

Pincus, Robert; Forster, Piers M.; Stevens, Bjorn

2016-09-27

The phrasing of the first of three questions motivating CMIP6 – “How does the Earth system respond to forcing?” – suggests that forcing is always well-known, yet the radiative forcing to which this question refers has historically been uncertain in coordinated experiments even as understanding of how best to infer radiative forcing has evolved. The Radiative Forcing Model Intercomparison Project (RFMIP) endorsed by CMIP6 seeks to provide a foundation for answering the question through three related activities: (i) accurate characterization of the effective radiative forcing relative to a near-preindustrial baseline and careful diagnosis of the components of this forcing; (ii) assessment ofmore » the absolute accuracy of clear-sky radiative transfer parameterizations against reference models on the global scales relevant for climate modeling; and (iii) identification of robust model responses to tightly specified aerosol radiative forcing from 1850 to present. Complete characterization of effective radiative forcing can be accomplished with 180 years (Tier 1) of atmosphere-only simulation using a sea-surface temperature and sea ice concentration climatology derived from the host model's preindustrial control simulation. Assessment of parameterization error requires trivial amounts of computation but the development of small amounts of infrastructure: new, spectrally detailed diagnostic output requested as two snapshots at present-day and preindustrial conditions, and results from the model's radiation code applied to specified atmospheric conditions. In conclusion, the search for robust responses to aerosol changes relies on the CMIP6 specification of anthropogenic aerosol properties; models using this specification can contribute to RFMIP with no additional simulation, while those using a full aerosol model are requested to perform at least one and up to four 165-year coupled ocean–atmosphere simulations at Tier 1.« less

Soot Particle Studies - Instrument Inter-Comparison – Project Overview

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cross, E.; Sedlacek, A.; Onasch, T. B.

2010-03-06

An inter-comparison study of instruments designed to measure the microphysical and optical properties of soot particles was completed. The following mass-based instruments were tested: Couette Centrifugal Particle Mass Analyzer (CPMA), Time-of-Flight Aerosol Mass Spectrometer - Scanning Mobility Particle Sizer (AMS-SMPS), Single Particle Soot Photometer (SP2), Soot Particle-Aerosol Mass Spectrometer (SP-AMS) and Photoelectric Aerosol Sensor (PAS2000CE). Optical instruments measured absorption (photoacoustic, interferometric, and filter-based), scattering (in situ), and extinction (light attenuation within an optical cavity). The study covered an experimental matrix consisting of 318 runs that systematically tested the performance of instruments across a range of parameters including: fuel equivalence ratiomore » (1.8 {le} {phi} {le} 5), particle shape (mass-mobility exponent (D{sub f m}), 2.0 {le} D{sub f m} {le} 3.0), particle mobility size (30 {le} d{sub m} {le} 300 nm), black carbon mass (0.07 {le} m{sub BC} {le} 4.2 fg) and particle chemical composition. In selected runs, particles were coated with sulfuric acid or dioctyl sebacate (DOS) (0.5 {le} {Delta}r{sub ve} {le} 201 nm) where {Delta}r{sub ve} is the change in the volume equivalent radius due to the coating material. The effect of non-absorbing coatings on instrument response was determined. Changes in the morphology of fractal soot particles were monitored during coating and denuding processes and the effect of particle shape on instrument response was determined. The combination of optical and mass based measurements was used to determine the mass specific absorption coefficient for denuded soot particles. The single scattering albedo of the particles was also measured. An overview of the experiments and sample results are presented.« less

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vives i Batlle, J.; Beresford, N. A.; Beaugelin-Seiller, K.

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of 90Sr, 131I and 137Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and whichmore » uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.« less

The Second Cabauw Intercomparison of Nitrogen Dioxide Measuring Instruments (CINDI-2)

NASA Astrophysics Data System (ADS)

Van Roozendael, M.; Hendrick, F.; Apituley, A.; Kreher, K.; Friess, U.; Richter, A.; Wagner, T.; Fehr, T.

2017-12-01

For the validation of space borne UV-Vis observations of air quality gases, ground based remote-sensing instruments using the MAXDOAS technique are an excellent choice, since they rely on similar retrieval techniques as the observations from orbit. Over the last decade, MAXDOAS instruments of various designs (including PANDORA systems) have been deployed worldwide forming the basis for a global ground based reference network suitable for the validation of future satellite sensors, such as TROPOMI/Sentinel-5 precursor, GEMS, TEMPO, and Sentinel 4 and 5. To ensure proper traceability of these observations, assess their accuracy and progress towards harmonized data acquisition and delivery, a thorough intercomparison campaign known as the Second Cabauw Intercomparison of Nitrogen Dioxide Measuring Instruments (CINDI-2) was held in Cabauw, The Netherlands during the month of September 2016. About 35 MAXDOAS instruments operated by 25 different groups were deployed, together with systems providing key ancillary in-situ measurements of NO2 and aerosol optical properties, as well as vertical profiles of NO2 by lidar and sonde and vertical profiles of aerosol optical properties by Raman lidar. We provide an overview of the main outcome of the campaign, which included a formal semi-blind slant column intercomparison and a number of additional exercises aiming at assessing the potential of the MAXDOAS technique for retrieving vertically-resolved information on NO2, aerosol, HCHO, O3 and a few other more challenging species such as HONO and glyoxal.

An intercomparison of aircraft instrumentation for tropospheric measurements of sulfur dioxide

NASA Technical Reports Server (NTRS)

Gregory, Gerald L.; Davis, Douglas D.; Beltz, Nobert; Bandy, Alan R.; Ferek, Ronald J.; Thornton, Donald C.

1993-01-01

As part of the NASA Tropospheric Chemistry Program, a series of field intercomparisons have been conducted to evaluate the state-of-the art for measuring key tropospheric species. One of the objectives of the third intercomparison campaign in this series, Chemical Instrumentation Test and Evaluation 3 (CITE 3), was to evaluate instrumentation for making reliable tropospheric aircraft measurements of sulfur dioxide, dimethyl sulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide. This paper reports the results of the intercomparisons of five sulfur dioxide measurement methods ranging from filter techniques, in which samples collected in flight are returned to the laboratory for analyses (chemiluminescent or ion chromatographic), to near real-time, in-flight measurements via gas chromatographic, mass spectrometric, and chemiluminescent techniques. All techniques showed some tendency to track sizeable changes in ambient SO2 such as those associated with altitude changes. For SO2 mixing ratios in the range of 200 pptv to a few ppbv, agreement among the techniques varies from about 30% to several orders of magnitude, depending upon the pair of measurements intercompared. For SO2 mixing ratios less than 200 pptv, measurements from the techniques are uncorrelated. In general, observed differences in the measurement of standards do not account for the flight results. The CITE 3 results do not unambiguously identify one or more of the measurement techniques as providing valid or invalid SO2 measurements, but identify the range of 'potential' uncertainty in SO2 measurements reported by currently available instrumentation and as measured under realistic aircraft environments.

Intercomparison of Operational Ocean Forecasting Systems in the framework of GODAE

NASA Astrophysics Data System (ADS)

Hernandez, F.

2009-04-01

One of the main benefits of the GODAE 10-year activity is the implementation of ocean forecasting systems in several countries. In 2008, several systems are operated routinely, at global or basin scale. Among them, the BLUElink (Australia), HYCOM (USA), MOVE/MRI.COM (Japan), Mercator (France), FOAM (United Kingdom), TOPAZ (Norway) and C-NOOFS (Canada) systems offered to demonstrate their operational feasibility by performing an intercomparison exercise during a three months period (February to April 2008). The objectives were: a) to show that operational ocean forecasting systems are operated routinely in different countries, and that they can interact; b) to perform in a similar way a scientific validation aimed to assess the quality of the ocean estimates, the performance, and forecasting capabilities of each system; and c) to learn from this intercomparison exercise to increase inter-operability and collaboration in real time. The intercomparison relies on the assessment strategy developed for the EU MERSEA project, where diagnostics over the global ocean have been revisited by the GODAE contributors. This approach, based on metrics, allow for each system: a) to verify if ocean estimates are consistent with the current general knowledge of the dynamics; and b) to evaluate the accuracy of delivered products, compared to space and in-situ observations. Using the same diagnostics also allows one to intercompare the results from each system consistently. Water masses and general circulation description by the different systems are consistent with WOA05 Levitus climatology. The large scale dynamics (tropical, subtropical and subpolar gyres ) are also correctly reproduced. At short scales, benefit of high resolution systems can be evidenced on the turbulent eddy field, in particular when compared to eddy kinetic energy deduced from satellite altimetry of drifter observations. Comparisons to high resolution SST products show some discrepancies on ocean surface representation, either due to model and forcing fields errors, or assimilation scheme efficiency. Comparisons to sea-ice satellite products also evidence discrepancies linked to model, forcing and assimilation strategies of each forecasting system. Key words: Intercomparison, ocean analysis, operational oceanography, system assessment, metrics, validation GODAE Intercomparison Team: L. Bertino (NERSC/Norway), G. Brassington (BMRC/Australia), E. Chassignet (FSU/USA), J. Cummings (NRL/USA), F. Davidson (DFO/Canda), M. Drévillon (CERFACS/France), P. Hacker (IPRC/USA), M. Kamachi (MRI/Japan), J.-M. Lellouche (CERFACS/France), K. A. Lisæter (NERSC/Norway), R. Mahdon (UKMO/UK), M. Martin (UKMO/UK), A. Ratsimandresy (DFO/Canada), and C. Regnier (Mercator Ocean/France)

Inconsistent Strategies to Spin up Models in CMIP5: Implications for Ocean Biogeochemical Model Performance Assessment

NASA Technical Reports Server (NTRS)

Seferian, Roland; Gehlen, Marion; Bopp, Laurent; Resplandy, Laure; Orr, James C.; Marti, Olivier; Dunne, John P.; Christian, James R.; Doney, Scott C.; Ilyina, Tatiana;

GEOS observation systems intercomparison investigation results

NASA Technical Reports Server (NTRS)

Berbert, J. H.

1974-01-01

The results of an investigation designed to determine the relative accuracy and precision of the different types of geodetic observation systems used by NASA is presented. A collocation technique was used to minimize the effects of uncertainties in the relative station locations and in the earth's gravity field model by installing accurate reference tracking systems close to the systems to be compared, and by precisely determining their relative survey. The Goddard laser and camera systems were shipped to selected sites, where they tracked the GEOS satellite simultaneously with other systems for an intercomparison observation.

Intercomparison of techniques for the non-invasive measurement of bone mass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cohn, S.H.

1981-01-01

A variety of methods are presently available for the non-invasive measurement of bone mass of both normal individuals and patients with metabolic disorders. Chief among these methods are radiographic techniques such as radiogrammetry, photon absorptiometry, computer tomography, Compton scattering and neutron activation analysis. In this review, the salient features of the bone measurement techniques are discussed along with their accuracy and precision. The advantages and disadvantages of the various techniques for measuring bone mass are summarized. Where possible, intercomparisons are made of the various techniques.

Intercomparison of photon dose measurements at the 8 MeV electron accelerator

NASA Astrophysics Data System (ADS)

Angelescu, T.; Ghiordănescu, N.; Băl ţă ţeanu, N.; Labău, V.; Vasilescu, A.

1997-02-01

Measurements of dose with thermoluminescent detectors (TLD) and an ionisation chamber were performed in the range of 5-70 Gy in the electron bremsstrahlung field with a maximum energy of 8 MeV of the Bucharest linear accelerator. Previous calibration was done with a 60Co source. The results of the intercomparison were used in dosimetry of the n - γ field of the ΣΣ irradiation facility, with a photon spectrum similar to the 8 MeV bremsstrahlung field [T. Angelescu et al., Nucl. Instr. and Meth. A 378 (1996) 594].

Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity from Observations

NASA Technical Reports Server (NTRS)

Marvel, Kate; Pincus, Robert; Schmidt, Gavin A.; Miller, Ron L.

2018-01-01

An emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979-2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2-radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long-term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long-term sensitivity.

Internal Variability and Disequilibrium Confound Estimates of Climate Sensitivity From Observations

NASA Astrophysics Data System (ADS)

Marvel, Kate; Pincus, Robert; Schmidt, Gavin A.; Miller, Ron L.

2018-02-01

An emerging literature suggests that estimates of equilibrium climate sensitivity (ECS) derived from recent observations and energy balance models are biased low because models project more positive climate feedback in the far future. Here we use simulations from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to show that across models, ECS inferred from the recent historical period (1979-2005) is indeed almost uniformly lower than that inferred from simulations subject to abrupt increases in CO2 radiative forcing. However, ECS inferred from simulations in which sea surface temperatures are prescribed according to observations is lower still. ECS inferred from simulations with prescribed sea surface temperatures is strongly linked to changes to tropical marine low clouds. However, feedbacks from these clouds are a weak constraint on long-term model ECS. One interpretation is that observations of recent climate changes constitute a poor direct proxy for long-term sensitivity.

Pareto-Optimal Estimates of California Precipitation Change

NASA Astrophysics Data System (ADS)

Langenbrunner, Baird; Neelin, J. David

2017-12-01

In seeking constraints on global climate model projections under global warming, one commonly finds that different subsets of models perform well under different objective functions, and these trade-offs are difficult to weigh. Here a multiobjective approach is applied to a large set of subensembles generated from the Climate Model Intercomparison Project phase 5 ensemble. We use observations and reanalyses to constrain tropical Pacific sea surface temperatures, upper level zonal winds in the midlatitude Pacific, and California precipitation. An evolutionary algorithm identifies the set of Pareto-optimal subensembles across these three measures, and these subensembles are used to constrain end-of-century California wet season precipitation change. This methodology narrows the range of projections throughout California, increasing confidence in estimates of positive mean precipitation change. Finally, we show how this technique complements and generalizes emergent constraint approaches for restricting uncertainty in end-of-century projections within multimodel ensembles using multiple criteria for observational constraints.

Mexican national pyronometer network calibration

NASA Astrophysics Data System (ADS)

VAldes, M.; Villarreal, L.; Estevez, H.; Riveros, D.

2013-12-01

In order to take advantage of the solar radiation as an alternate energy source it is necessary to evaluate the spatial and temporal availability. The Mexican National Meterological Service (SMN) has a network with 136 meteorological stations, each coupled with a pyronometer for measuring the global solar radiation. Some of these stations had not been calibrated in several years. The Mexican Department of Energy (SENER) in order to count on a reliable evaluation of the solar resource funded this project to calibrate the SMN pyrometer network and validate the data. The calibration of the 136 pyronometers by the intercomparison method recommended by the World Meterological Organization (WMO) requires lengthy observations and specific environmental conditions such as clear skies and a stable atmosphere, circumstances that determine the site and season of the calibration. The Solar Radiation Section of the Instituto de Geofísica of the Universidad Nacional Autónoma de México is a Regional Center of the WMO and is certified to carry out the calibration procedures and emit certificates. We are responsible for the recalibration of the pyronometer network of the SMN. A continuous emission solar simulator with exposed areas with 30cm diameters was acquired to reduce the calibration time and not depend on atmospheric conditions. We present the results of the calibration of 10 thermopile pyronometers and one photovoltaic cell by the intercomparison method with more than 10000 observations each and those obtained with the solar simulator.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yim, Bo; Yeh, Sang -Wook; Sohn, Byung -Ju

Observational evidence shows that the Walker circulation (WC) in the tropical Pacific has strengthened in recent decades. In this study, we examine the WC trend for 1979–2005 and its relationship with the precipitation associated with the El Niño Southern Oscillation (ENSO) using the sea surface temperature (SST)-constrained Atmospheric Model Intercomparison Project (AMIP) simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models. All of the 29 models show a strengthening of the WC trend in response to an increase in the SST zonal gradient along the equator. Despite the same SST-constrained AMIP simulations, however, a large diversity ismore » found among the CMIP5 climate models in the magnitude of the WC trend. The relationship between the WC trend and precipitation anomalies (PRCPAs) associated with ENSO (ENSO-related PRCPAs) shows that the longitudinal position of the ENSO-related PRCPAs in the western tropical Pacific is closely related to the magnitude of the WC trend. Specifically, it is found that the strengthening of the WC trend is large (small) in the CMIP5 AMIP simulations in which the ENSO-related PRCPAs are located relatively westward (eastward) in the western tropical Pacific. Furthermore, the zonal shift of the ENSO-related precipitation in the western tropical Pacific, which is associated with the climatological mean precipitation in the tropical Pacific, could play an important role in modifying the WC trend in the CMIP5 climate models.« less

Effects of anthropogenic activity emerging as intensified extreme precipitation over China

NASA Astrophysics Data System (ADS)

Li, Huixin; Chen, Huopo; Wang, Huijun

2017-07-01

This study aims to provide an assessment of the effects of anthropogenic (ANT) forcings and other external factors on observed increases in extreme precipitation over China from 1961 to 2005. Extreme precipitation is represented by the annual maximum 1 day precipitation (RX1D) and the annual maximum 5 day consecutive precipitation (RX5D), and these variables are investigated using observations and simulations from the Coupled Model Intercomparison Project phase 5. The analyses mainly focus on the probability-based index (PI), which is derived from RX1D and RX5D by fitting generalized extreme value distributions. The results indicate that the simulations that include the ANT forcings provide the best representation of the spatial and temporal characteristics of extreme precipitation over China. We use the optimal fingerprint method to obtain the univariate and multivariate fingerprints of the responses to external forcings. The results show that only the ANT forcings are detectable at a 90% confidence level, both individually and when natural forcings are considered simultaneously. The impact of the forcing associated with greenhouse gases (GHGs) is also detectable in RX1D, but its effects cannot be separated from those of combinations of forcings that exclude the GHG forcings in the two-signal analyses. Besides, the estimated changes of PI, extreme precipitation, and events with a 20 year return period under nonstationary climate states are potentially attributable to ANT or GHG forcings, and the relationships between extreme precipitation and temperature from ANT forcings show agreement with observations.

Using prior information to separate the temperature response to greenhouse gas forcing from that of aerosols - Estimating the transient climate response

NASA Astrophysics Data System (ADS)

Schurer, Andrew; Hegerl, Gabriele

2016-04-01

The evaluation of the transient climate response (TCR) is of critical importance to policy makers as it can be used to calculate a simple estimate of the expected warming given predicted greenhouse gas emissions. Previous studies using optimal detection techniques have been able to estimate a TCR value from the historic record using simulations from some of the models which took part in the Coupled Model Intercomparison Project Phase 5 (CMIP5) but have found that others give unconstrained results. At least partly this is due to degeneracy between the greenhouse gas and aerosol signals which makes separation of the temperature response to these forcings problematic. Here we re-visit this important topic by using an adapted optimal detection analysis within a Bayesian framework. We account for observational uncertainty by the use of an ensemble of instrumental observations, and model uncertainty by combining the results from several different models. This framework allows the use of prior information which is found to help separate the response to the different forcings leading to a more constrained estimate of TCR.

First results of the CINDI-2 semi-blind MAX-DOAS intercomparison

NASA Astrophysics Data System (ADS)

Kreher, Karin; van Roozendael, Michel; Hendrick, Francois; Apituley, Arnoud; Friess, Udo; Lampel, Johannes; Piters, Ankie; Richter, Andreas; Wagner, Thomas; Cindi-2 Participants, All

2017-04-01

The second Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI-2) took place at the Cabauw Experimental Site for Atmospheric Research (CESAR; Utrecht area, The Netherlands) from 25 August until 7 October 2016. The goals of this inter-comparison campaign are to support the creation of high-quality ground-based data sets (e.g. to provide reliable long-term time series for trend analysis and satellite data validation), to characterise and better understand the differences between a large number of MAX-DOAS and DOAS instruments and analysis methods, and to contribute to a harmonisation of the measurement settings and retrieval methods. During a time period of 17 days, from 12 to 28 September 2016, a formal semi-blind intercomparison was held following a detailed measurement protocol. The development of this protocol was based on the experience gained during the first CINDI campaign held in 2009 as well as more recent projects and campaigns such as the MADCAT campaign in Mainz, Germany, in 2013. Strong emphasis was put on the careful synchronisation of the measurement sequence and on exact alignment of the elevation angles using horizon scans and lamp measurements. In this presentation, we provide an overview and some highlights of the MAX-DOAS semi-blind intercomparison campaign. We will introduce the participating groups, their instruments and the measurement protocol details, and then summarize the campaign outcomes to date. The CINDI-2 data sets have been investigated using a range of diagnostics including comparisons of daily time series and relative differences between the data sets, regression analysis and correlation plots. The data products so far investigated are NO2 (nitrogen dioxide) in the UV and visible wavelength region, O4 (oxygen dimer) in the same two wavelength intervals, O3 (ozone) in the UV and visible wavelength region, HCHO (formaldehyde) and NO2 in an additional (smaller) wavelength range in the visible. The results based on the regression analysis are presented in summary plots and tables, addressing MAX-DOAS and twilight zenith sky measurements separately. Further information on instrumental details such as the alignment of the viewing direction and elevation and the field of view are also summarized and included in the overall interpretation.

Atmospheric Correction Inter-comparison Exercise (ACIX)

NASA Astrophysics Data System (ADS)

Vermote, E.; Doxani, G.; Gascon, F.; Roger, J. C.; Skakun, S.

2017-12-01

The free and open data access policy to Landsat-8 (L-8) and Sentinel-2 (S-2) satellite imagery has encouraged the development of atmospheric correction (AC) approaches for generating Bottom-of-Atmosphere (BOA) products. Several entities have started to generate (or plan to generate in the short term) BOA reflectance products at global scale for L-8 and S-2 missions. To this end, the European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) have initiated an exercise on the inter-comparison of the available AC processors. The results of the exercise are expected to point out the strengths and weaknesses, as well as communalities and discrepancies of various AC processors, in order to suggest and define ways for their further improvement. In particular, 11 atmospheric processors from five different countries participate in ACIX with the aim to inter-compare their performance when applied to L-8 and S-2 data. All the processors should be operational without requiring parametrization when applied on different areas. A protocol describing in details the inter-comparison metrics and the test dataset based on the AERONET sites has been agreed unanimously during the 1st ACIX workshop in June 2016. In particular, a basic and an advanced run of each of the processor were requested in the frame of ACIX, with the aim to draw robust and reliable conclusions on the processors' performance. The protocol also describes the comparison metrics of the aerosol optical thickness and water vapour products of the processors with the corresponding AERONET measurements. Moreover, concerning the surface reflectances, the inter-comparison among the processors is defined, as well as the comparison with the MODIS surface reflectance and with a reference surface reflectance product. Such a reference product will be obtained using the AERONET characterization of the aerosol (size distribution and refractive indices) and an accurate radiative transfer code. The inter-comparison outcomes were presented and discussed among the ACIX participants in the 2nd ACIX workshop, which was held on 11-12 April 2017 (ESRIN/ESA) and a detailed report was compiled. The proposed presentation is an opportunity for the user community to be informed about the ACIX results and conclusions.

Stratospheric Ozone Intercomparison Campaign (STOIC) 1989: Overview

NASA Technical Reports Server (NTRS)

Margitan, J. J.; Barnes, R. A.; Brothers, G. B.; Butler, J.; Burris, J.; Connor, B. J.; Ferrare, R. A.; Kerr, J. B.; Komhyr, W. D.; McCormick, M. P.;

Radiance and Jacobian Intercomparison of Radiative Transfer Models Applied to HIRS and AMSU Channels

NASA Technical Reports Server (NTRS)

Garand, L.; Turner, D. S.; Larocque, M.; Bates, J.; Boukabara, S.; Brunel, P.; Chevallier, F.; Deblonde, G.; Engelen, R.; Hollingshead, M.;

Radiance and Jacobian Intercomparison of Radiative Transfer Models Applied to HIRS and AMSU Channels

NASA Technical Reports Server (NTRS)

Garand, L.; Turner, D. S.; Larocque, M.; Bates, J.; Boukabara, S.; Brunel, P.; Chevallier, F.; Deblonde, G.; Engelen, R.; Atlas, Robert (Technical Monitor)

2000-01-01

The goals of this study are the evaluation of current fast radiative transfer models (RTMs) and line-by-line (LBL) models. The intercomparison focuses on the modeling of 11 representative sounding channels routinely used at numerical weather prediction centers: seven HIRS (High-resolution Infrared Sounder) and four AMSU (Advanced Microwave Sounding Unit) channels. Interest in this topic was evidenced by the participation of 24 scientists from 16 institutions. An ensemble of 42 diverse atmospheres was used and results compiled for 19 infrared models and 10 microwave models, including several LBL RTMs. For the first time, not only radiances, but also Jacobians (of temperature, water vapor, and ozone) were compared to various LBL models for many channels. In the infrared, LBL models typically agree to within 0.05-0.15 K (standard deviation) in terms of top-of-the-atmosphere brightness temperature (BT). Individual differences up to 0.5 K still exist, systematic in some channels, and linked to the type of atmosphere in others. The best fast models emulate LBL BTs to within 0.25 K, but no model achieves this desirable level of success for all channels. The ozone modeling is particularly challenging. In the microwave, fast models generally do quite well against the LBL model to which they were tuned. However significant differences were noted among LBL models. Extending the intercomparison to the Jacobians proved very useful in detecting subtle and more obvious modeling errors. In addition, total and single gas optical depths were calculated, which provided additional insight on the nature of differences. Recommendations for future intercomparisons are suggested.

GMMIP (v1.0) contribution to CMIP6: Global Monsoons Model Inter-comparison Project

NASA Astrophysics Data System (ADS)

Zhou, Tianjun; Turner, Andrew G.; Kinter, James L.; Wang, Bin; Qian, Yun; Chen, Xiaolong; Wu, Bo; Wang, Bin; Liu, Bo; Zou, Liwei; He, Bian

2016-10-01

The Global Monsoons Model Inter-comparison Project (GMMIP) has been endorsed by the panel of Coupled Model Inter-comparison Project (CMIP) as one of the participating model inter-comparison projects (MIPs) in the sixth phase of CMIP (CMIP6). The focus of GMMIP is on monsoon climatology, variability, prediction and projection, which is relevant to four of the "Grand Challenges" proposed by the World Climate Research Programme. At present, 21 international modeling groups are committed to joining GMMIP. This overview paper introduces the motivation behind GMMIP and the scientific questions it intends to answer. Three tiers of experiments, of decreasing priority, are designed to examine (a) model skill in simulating the climatology and interannual-to-multidecadal variability of global monsoons forced by the sea surface temperature during historical climate period; (b) the roles of the Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation in driving variations of the global and regional monsoons; and (c) the effects of large orographic terrain on the establishment of the monsoons. The outputs of the CMIP6 Diagnostic, Evaluation and Characterization of Klima experiments (DECK), "historical" simulation and endorsed MIPs will also be used in the diagnostic analysis of GMMIP to give a comprehensive understanding of the roles played by different external forcings, potential improvements in the simulation of monsoon rainfall at high resolution and reproducibility at decadal timescales. The implementation of GMMIP will improve our understanding of the fundamental physics of changes in the global and regional monsoons over the past 140 years and ultimately benefit monsoons prediction and projection in the current century.

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario.

PubMed

Vives I Batlle, J; Beresford, N A; Beaugelin-Seiller, K; Bezhenar, R; Brown, J; Cheng, J-J; Ćujić, M; Dragović, S; Duffa, C; Fiévet, B; Hosseini, A; Jung, K T; Kamboj, S; Keum, D-K; Kryshev, A; LePoire, D; Maderich, V; Min, B-I; Periáñez, R; Sazykina, T; Suh, K-S; Yu, C; Wang, C; Heling, R

2016-03-01

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of (90)Sr, (131)I and (137)Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6

DOE PAGES

O'Neill, Brian C.; Tebaldi, Claudia; van Vuuren, Detlef P.; ...

2016-09-28

Projections of future climate change play a fundamental role in improving understanding of the climate system as well as characterizing societal risks and response options. The Scenario Model Intercomparison Project (ScenarioMIP) is the primary activity within Phase 6 of the Coupled Model Intercomparison Project (CMIP6) that will provide multi-model climate projections based on alternative scenarios of future emissions and land use changes produced with integrated assessment models. Here, we describe ScenarioMIP's objectives, experimental design, and its relation to other activities within CMIP6. The ScenarioMIP design is one component of a larger scenario process that aims to facilitate a wide rangemore » of integrated studies across the climate science, integrated assessment modeling, and impacts, adaptation, and vulnerability communities, and will form an important part of the evidence base in the forthcoming Intergovernmental Panel on Climate Change (IPCC) assessments. Furthermore, it will provide the basis for investigating a number of targeted science and policy questions that are especially relevant to scenario-based analysis, including the role of specific forcings such as land use and aerosols, the effect of a peak and decline in forcing, the consequences of scenarios that limit warming to below 2°C, the relative contributions to uncertainty from scenarios, climate models, and internal variability, and long-term climate system outcomes beyond the 21st century. In order to serve this wide range of scientific communities and address these questions, a design has been identified consisting of eight alternative 21st century scenarios plus one large initial condition ensemble and a set of long-term extensions, divided into two tiers defined by relative priority. Some of these scenarios will also provide a basis for variants planned to be run in other CMIP6-Endorsed MIPs to investigate questions related to specific forcings. Harmonized, spatially explicit emissions and land use scenarios generated with integrated assessment models will be provided to participating climate modeling groups by late 2016, with the climate model simulations run within the 2017–2018 time frame, and output from the climate model projections made available and analyses performed over the 2018–2020 period.« less

The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Neill, Brian C.; Tebaldi, Claudia; van Vuuren, Detlef P.

2016-01-01

Projections of future climate change play a fundamental role in improving understanding of the climate system as well as characterizing societal risks and response options. The Scenario Model Intercomparison Project (ScenarioMIP) is the primary activity within Phase 6 of the Coupled Model Intercomparison Project (CMIP6) that will provide multi-model climate projections based on alternative scenarios of future emissions and land use changes produced with integrated assessment models. In this paper, we describe ScenarioMIP's objectives, experimental design, and its relation to other activities within CMIP6. The ScenarioMIP design is one component of a larger scenario process that aims to facilitate amore » wide range of integrated studies across the climate science, integrated assessment modeling, and impacts, adaptation, and vulnerability communities, and will form an important part of the evidence base in the forthcoming Intergovernmental Panel on Climate Change (IPCC) assessments. At the same time, it will provide the basis for investigating a number of targeted science and policy questions that are especially relevant to scenario-based analysis, including the role of specific forcings such as land use and aerosols, the effect of a peak and decline in forcing, the consequences of scenarios that limit warming to below 2 °C, the relative contributions to uncertainty from scenarios, climate models, and internal variability, and long-term climate system outcomes beyond the 21st century. To serve this wide range of scientific communities and address these questions, a design has been identified consisting of eight alternative 21st century scenarios plus one large initial condition ensemble and a set of long-term extensions, divided into two tiers defined by relative priority. Some of these scenarios will also provide a basis for variants planned to be run in other CMIP6-Endorsed MIPs to investigate questions related to specific forcings. Harmonized, spatially explicit emissions and land use scenarios generated with integrated assessment models will be provided to participating climate modeling groups by late 2016, with the climate model simulations run within the 2017–2018 time frame, and output from the climate model projections made available and analyses performed over the 2018–2020 period.« less

The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6

NASA Astrophysics Data System (ADS)

O'Neill, Brian C.; Tebaldi, Claudia; van Vuuren, Detlef P.; Eyring, Veronika; Friedlingstein, Pierre; Hurtt, George; Knutti, Reto; Kriegler, Elmar; Lamarque, Jean-Francois; Lowe, Jason; Meehl, Gerald A.; Moss, Richard; Riahi, Keywan; Sanderson, Benjamin M.

2016-09-01

Projections of future climate change play a fundamental role in improving understanding of the climate system as well as characterizing societal risks and response options. The Scenario Model Intercomparison Project (ScenarioMIP) is the primary activity within Phase 6 of the Coupled Model Intercomparison Project (CMIP6) that will provide multi-model climate projections based on alternative scenarios of future emissions and land use changes produced with integrated assessment models. In this paper, we describe ScenarioMIP's objectives, experimental design, and its relation to other activities within CMIP6. The ScenarioMIP design is one component of a larger scenario process that aims to facilitate a wide range of integrated studies across the climate science, integrated assessment modeling, and impacts, adaptation, and vulnerability communities, and will form an important part of the evidence base in the forthcoming Intergovernmental Panel on Climate Change (IPCC) assessments. At the same time, it will provide the basis for investigating a number of targeted science and policy questions that are especially relevant to scenario-based analysis, including the role of specific forcings such as land use and aerosols, the effect of a peak and decline in forcing, the consequences of scenarios that limit warming to below 2 °C, the relative contributions to uncertainty from scenarios, climate models, and internal variability, and long-term climate system outcomes beyond the 21st century. To serve this wide range of scientific communities and address these questions, a design has been identified consisting of eight alternative 21st century scenarios plus one large initial condition ensemble and a set of long-term extensions, divided into two tiers defined by relative priority. Some of these scenarios will also provide a basis for variants planned to be run in other CMIP6-Endorsed MIPs to investigate questions related to specific forcings. Harmonized, spatially explicit emissions and land use scenarios generated with integrated assessment models will be provided to participating climate modeling groups by late 2016, with the climate model simulations run within the 2017-2018 time frame, and output from the climate model projections made available and analyses performed over the 2018-2020 period.

Intercomparison of 30+ years of AVHRR and Landsat-5 TM Surface Reflectance using Multiple Pseudo-Invariant Calibration Sites

NASA Astrophysics Data System (ADS)

Santamaría-Artigas, A. E.; Franch, B.; Vermote, E.; Roger, J. C.; Justice, C. O.

2017-12-01

The 30+ years daily surface reflectance long term data record (LTDR) from the Advanced Very High Resolution Radiometer (AVHRR) is a valuable source of information for long-term studies of the Earth surface. This LTDR was generated by combining observations from multiple AVHRR sensors aboard different NOAA satellites starting from the early 1980s, and due to the lack of on-board calibration its quality should be evaluated. Previous studies have used observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) over pseudo-invariant calibration sites (PICS) as a calibrated reference to assess the performance of AVHRR products. However, this limits the evaluation to the period after MODIS launch. In this work, the AVHRR surface reflectance LTDR was evaluated against Landsat-5 Thematic Mapper (TM) data using observations from 4 well known pseudo-invariant calibration sites (i.e. Sonoran, Saharan, Sudan1, and Libya4) over an extended time period (1984-2011). For the intercomparison, AVHRR and TM observations of each site were extracted and averaged over a 20 km x 20 km area and aggregated to monthly mean values. In order to account for the spectral differences between sensors, Hyperion hyperspectral data from the Sonoran and Libya4 sites were convolved with sensor-specific relative spectral responses, and used to compute spectral band adjustment factors (SBAFs). Results of the intercomparison are reported in terms of the root mean square difference (RMSD) and determination coefficient (r2). In general, there is good agreement between the surface reflectance products from both sensors. The overall RMSD and r2 for all the sites and AVHRR/TM combinations were 0.03 and 0.85 for the red band, and 0.04 and 0.81 for the near-infrared band. These results show the strong performance of the AVHRR surface reflectance LTDR through all of the considered period. Thus, remarking its usefulness and value for long term Earth studies. Figure 1 shows the red (filled markers) and near-infrared (empty markers) surface reflectance from AVHRR and TM for the complete evaluation period over the Saharan (diamond), Libya4 (square), Sudan1 (triangle), and Sonoran (circle) PICS.

nonlinMIP contribution to CMIP6: model intercomparison project for non-linear mechanisms: physical basis, experimental design and analysis principles (v1.0)

NASA Astrophysics Data System (ADS)

Good, Peter; Andrews, Timothy; Chadwick, Robin; Dufresne, Jean-Louis; Gregory, Jonathan M.; Lowe, Jason A.; Schaller, Nathalie; Shiogama, Hideo

2016-11-01

nonlinMIP provides experiments that account for state-dependent regional and global climate responses. The experiments have two main applications: (1) to focus understanding of responses to CO2 forcing on states relevant to specific policy or scientific questions (e.g. change under low-forcing scenarios, the benefits of mitigation, or from past cold climates to the present day), or (2) to understand the state dependence (non-linearity) of climate change - i.e. why doubling the forcing may not double the response. State dependence (non-linearity) of responses can be large at regional scales, with important implications for understanding mechanisms and for general circulation model (GCM) emulation techniques (e.g. energy balance models and pattern-scaling methods). However, these processes are hard to explore using traditional experiments, which explains why they have had so little attention in previous studies. Some single model studies have established novel analysis principles and some physical mechanisms. There is now a need to explore robustness and uncertainty in such mechanisms across a range of models (point 2 above), and, more broadly, to focus work on understanding the response to CO2 on climate states relevant to specific policy/science questions (point 1). nonlinMIP addresses this using a simple, small set of CO2-forced experiments that are able to separate linear and non-linear mechanisms cleanly, with a good signal-to-noise ratio - while being demonstrably traceable to realistic transient scenarios. The design builds on the CMIP5 (Coupled Model Intercomparison Project Phase 5) and CMIP6 DECK (Diagnostic, Evaluation and Characterization of Klima) protocols, and is centred around a suite of instantaneous atmospheric CO2 change experiments, with a ramp-up-ramp-down experiment to test traceability to gradual forcing scenarios. In all cases the models are intended to be used with CO2 concentrations rather than CO2 emissions as the input. The understanding gained will help interpret the spread in policy-relevant scenario projections. Here we outline the basic physical principles behind nonlinMIP, and the method of establishing traceability from abruptCO2 to gradual forcing experiments, before detailing the experimental design, and finally some analysis principles. The test of traceability from abruptCO2 to transient experiments is recommended as a standard analysis within the CMIP5 and CMIP6 DECK protocols.

Forecasting Brassica rapa: Merging climate models with genotype specific process models for evaluation whole species response to climate change.

NASA Astrophysics Data System (ADS)

Pleban, J. R.; Mackay, D. S.; Ewers, B. E.; Weinig, C.; Guadagno, C. L.

2016-12-01

Human society has modified agriculture management practices and utilized a variety of breeding approaches to adapt to changing environments. Presently a dual pronged challenge has emerged as environmental change is occurring more rapidly while the demand of population growth on food supply is rising. Knowledge of how current agricultural practices will respond to these challenges can be informed through crafted prognostic modeling approaches. Amongst the uncertainties associated with forecasting agricultural production in a changing environment is evaluation of the responses across the existing genotypic diversity of crop species. Mechanistic models of plant productivity provide a means of genotype level parameterization allowing for a prognostic evaluation of varietal performance under changing climate. Brassica rapa represents an excellent species for this type of investigation because of its wide cultivation as well as large morphological and physiological diversity. We incorporated genotypic parameterization of B. rapa genotypes based on unique CO2 assimilation strategies, vulnerabilities to cavitation, and root to leaf area relationships into the TREES model. Three climate drivers, following the "business-as-usual" greenhouse gas emissions scenario (RCP 8.5) from Coupled Model Intercomparison Project, Phase 5 (CMIP5) were considered: temperature (T) along with associated changes in vapor pressure deficit (VPD), increasing CO2, as well as alternatives in irrigation regime across a temporal scale of present day to 2100. Genotypic responses to these drivers were evaluated using net primary productivity (NPP) and percent loss hydraulic conductance (PLC) as a measure of tolerance for a particular watering regime. Genotypic responses to T were witnessed as water demand driven by increases in VPD at 2050 and 2100 drove some genotypes to greater PLC and in a subset of these saw periodic decreases in NPP during a growing season. Genotypes able to withstand the greater water demand showed lower NPP yields relative to hydraulically aggressive genotypes but saw limited PLC. Expansion of this analysis to large recombinant inbred populations may inform breeders in identification of trait combinations needed to meet the coupled challenge of rapid environmental change and increase food demand.

Status report on the Zagreb Radiocarbon Laboratory - AMS and LSC results of VIRI intercomparison samples

NASA Astrophysics Data System (ADS)

Sironić, Andreja; Krajcar Bronić, Ines; Horvatinčić, Nada; Barešić, Jadranka; Obelić, Bogomil; Felja, Igor

2013-01-01

A new line for preparation of the graphite samples for 14C dating by Accelerator Mass Spectrometry (AMS) in the Zagreb Radiocarbon Laboratory has been validated by preparing graphite from various materials distributed within the Fifth International Radiocarbon Intercomparison (VIRI) study. 14C activity of prepared graphite was measured at the SUERC AMS facility. The results are statistically evaluated by means of the z-score and u-score values. The mean z-score value of 28 prepared VIRI samples is (0.06 ± 0.23) showing excellent agreement with the consensus VIRI values. Only one sample resulted in the u-score value above the limit of acceptability (defined for the confidence interval of 99%) and this was probably caused by a random contamination of the graphitization rig. After the rig had been moved to the new adapted and isolated room, all u-score values laid within the acceptable limits. Our LSC results of VIRI intercomparison samples are also presented and they are all accepted according to the u-score values.

An Overview of Measurement Comparisons from the INTEX-B/MILAGRO Airborne Field Campaign

NASA Technical Reports Server (NTRS)

Kleb, Mary M.; Chen, Gao; Crawford, James H.; Flocke, Frank M.; Brown, Clyde C.

2011-01-01

As part of the NASA's INTEX-B mission, the NASA DC-8 and NSF C-130 conducted three wing-tip to wing-tip comparison flights. The intercomparison flights sampled a variety of atmospheric conditions (polluted urban, non-polluted, marine boundary layer, clean and polluted free troposphere). These comparisons form a basis to establish data consistency, but also should also be viewed as a continuation of efforts aiming to better understand and reduce measurement differences as identified in earlier field intercomparison exercises. This paper provides a comprehensive overview of 140 intercomparisons of data collected as well as a record of the measurement consistency demonstrated during INTEX-B. It is the primary goal to provide necessary information for the future research to determine if the observations from different INTEX-B platforms/instrument are consistent within the PI reported uncertainties and used in integrated analysis. This paper may also contribute to the formulation strategy for future instrument developments. For interpretation and most effective use of these results, the reader is strongly urged to consult with the instrument principle investigator.

Ice Sheet Model Intercomparison Project (ISMIP6) contribution to CMIP6

PubMed Central

Nowicki, Sophie M.J.; Payne, Tony; Larour, Eric; Seroussi, Helene; Goelzer, Heiko; Lipscomb, William; Gregory, Jonathan; Abe-Ouchi, Ayako; Shepherd, Andrew

2018-01-01

Reducing the uncertainty in the past, present and future contribution of ice sheets to sea-level change requires a coordinated effort between the climate and glaciology communities. The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary activity within the Coupled Model Intercomparison Project – phase 6 (CMIP6) focusing on the Greenland and Antarctic Ice Sheets. In this paper, we describe the framework for ISMIP6 and its relationship to other activities within CMIP6. The ISMIP6 experimental design relies on CMIP6 climate models and includes, for the first time within CMIP, coupled ice sheet – climate models as well as standalone ice sheet models. To facilitate analysis of the multi-model ensemble and to generate a set of standard climate inputs for standalone ice sheet models, ISMIP6 defines a protocol for all variables related to ice sheets. ISMIP6 will provide a basis for investigating the feedbacks, impacts, and sea-level changes associated with dynamic ice sheets and for quantifying the uncertainty in ice-sheet-sourced global sea-level change. PMID:29697697

The Continuous Intercomparison of Radiation Codes (CIRC): Phase I Cases

NASA Technical Reports Server (NTRS)

Oreopoulos, Lazaros; Mlawer, Eli; Delamere, Jennifer; Shippert, Timothy; Turner, David D.; Miller, Mark A.; Minnis, Patrick; Clough, Shepard; Barker, Howard; Ellingson, Robert

2007-01-01

CIRC aspires to be the successor to ICRCCM (Intercomparison of Radiation Codes in Climate Models). It is envisioned as an evolving and regularly updated reference source for GCM-type radiative transfer (RT) code evaluation with the principle goal to contribute in the improvement of RT parameterizations. CIRC is jointly endorsed by DOE's Atmospheric Radiation Measurement (ARM) program and the GEWEX Radiation Panel (GRP). CIRC's goal is to provide test cases for which GCM RT algorithms should be performing at their best, i.e, well characterized clear-sky and homogeneous, overcast cloudy cases. What distinguishes CIRC from previous intercomparisons is that its pool of cases is based on observed datasets. The bulk of atmospheric and surface input as well as radiative fluxes come from ARM observations as documented in the Broadband Heating Rate Profile (BBHRP) product. BBHRP also provides reference calculations from AER's RRTM RT algorithms that can be used to select the most optimal set of cases and to provide a first-order estimate of our ability to achieve radiative flux closure given the limitations in our knowledge of the atmospheric state.

Ice Sheet Model Intercomparison Project (ISMIP6) Contribution to CMIP6

NASA Technical Reports Server (NTRS)

Nowicki, Sophie M. J.; Payne, Tony; Larour, Eric; Seroussi, Helene; Goelzer, Heiko; Lipscomb, William; Gregory, Jonathan; Abe-Ouchi, Ayako; Shepherd, Andrew

2016-01-01

Reducing the uncertainty in the past, present, and future contribution of ice sheets to sea-level change requires a coordinated effort between the climate and glaciology communities. The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary activity within the Coupled Model Intercomparison Project phase 6 (CMIP6) focusing on the Greenland and Antarctic ice sheets. In this paper, we describe the framework for ISMIP6 and its relationship with other activities within CMIP6. The ISMIP6 experimental design relies on CMIP6 climate models and includes, for the first time within CMIP, coupled ice-sheetclimate models as well as standalone ice-sheet models. To facilitate analysis of the multi-model ensemble and to generate a set of standard climate inputs for standalone ice-sheet models, ISMIP6 defines a protocol for all variables related to ice sheets. ISMIP6 will provide a basis for investigating the feedbacks, impacts, and sea-level changes associated with dynamic ice sheets and for quantifying the uncertainty in ice-sheet-sourced global sea-level change.

An International Marine-Atmospheric 222Rn Measurement Intercomparison in Bermuda Part I: NIST Calibration and Methodology for Standardized Sample Additions

PubMed Central

Collé, R.; Unterweger, M. P.; Hodge, P. A.; Hutchinson, J. M. R.

1996-01-01

As part of an international 222Rn measurement intercomparison conducted at Bermuda in October 1991, NIST provided standardized sample additions of known, but undisclosed (“blind”) 222Rn concentrations that could be related to U.S. national standards. The standardized sample additions were obtained with a calibrated 226Ra source and a specially-designed manifold used to obtain well-known dilution factors from simultaneous flow-rate measurements. The additions were introduced over sampling periods of several hours (typically 4 h) into a common streamline on a sampling tower used by the participating laboratories for their measurements. The standardized 222Rn activity concentrations for the intercomparison ranged from approximately 2.5 Bq · m−3 to 35 Bq · m−3 (of which the lower end of this range approached concentration levels for ambient Bermudian air) and had overall uncertainties, approximating a 3 standard deviation uncertainty interval, of about 6 % to 13 %. This paper describes the calibration and methodology for the standardized sample additions. PMID:27805090

Soundings from SGP, June 2014 Sonde Comparison Study

DOE Data Explorer

Jensen, Michael

2015-03-06

In early June 2014, a radiosonde intercomparison trial was undertaken at the SGP Central Facility site with the goal of quantifying the relative performance of the RS92-SGP/MW31 and RS41-SG/MW41 radiosondes/systems. The June time period at SGP represents a springtime mid-latitude convective environment where the extensive remote sensing observations at the SGP site were used to further quantify the environment during the intercomparison. Over the course of five days (3 - 8 June) a total of 20 balloon launches were completed with efforts to sample the entire diurnal cycle and a variety of cloud conditions

Inter-comparison of boron concentration measurements at INFN-University of Pavia (Italy) and CNEA (Argentina).

PubMed

Portu, Agustina; Postuma, Ian; Gadan, Mario Alberto; Saint Martin, Gisela; Olivera, María Silvina; Altieri, Saverio; Protti, Nicoletta; Bortolussi, Silva

2015-11-01

An inter-comparison of three boron determination techniques was carried out between laboratories from INFN-University of Pavia (Italy) and CNEA (Argentina): alpha spectrometry (alpha-spect), neutron capture radiography (NCR) and quantitative autoradiography (QTA). Samples of different nature were analysed: liquid standards, liver homogenates and tissue samples from different treatment protocols. The techniques showed a good agreement in a concentration range of interest in BNCT (1-100ppm), thus demonstrating their applicability as precise methods to quantify boron and determine its distribution in tissues. Copyright © 2015 Elsevier Ltd. All rights reserved.

International Intercomparison of Regular Transmittance Scales

NASA Astrophysics Data System (ADS)

Eckerle, K. L.; Sutter, E.; Freeman, G. H. C.; Andor, G.; Fillinger, L.

1990-01-01

An intercomparison of the regular spectral transmittance scales of NIST, Gaithersburg, MD (USA); PTB, Braunschweig (FRG); NPL, Teddington, Middlesex (UK); and OMH, Budapest (H) was accomplished using three sets of neutral glass filters with transmittances ranging from approximately 0.92 to 0.001. The difference between the results from the reference spectrophotometers of the laboratories was generally smaller than the total uncertainty of the interchange. The relative total uncertainty ranges from 0.05% to 0.75% for transmittances from 0.92 to 0.001. The sample-induced error was large - contributing 40% or more of the total except in a few cases.

Soil sampling strategies: evaluation of different approaches.

PubMed

de Zorzi, Paolo; Barbizzi, Sabrina; Belli, Maria; Mufato, Renzo; Sartori, Giuseppe; Stocchero, Giulia

2008-11-01

The National Environmental Protection Agency of Italy (APAT) performed a soil sampling intercomparison, inviting 14 regional agencies to test their own soil sampling strategies. The intercomparison was carried out at a reference site, previously characterised for metal mass fraction distribution. A wide range of sampling strategies, in terms of sampling patterns, type and number of samples collected, were used to assess the mean mass fraction values of some selected elements. The different strategies led in general to acceptable bias values (D) less than 2sigma, calculated according to ISO 13258. Sampling on arable land was relatively easy, with comparable results between different sampling strategies.

What Climate Sensitivity Index Is Most Useful for Projections?

NASA Astrophysics Data System (ADS)

Grose, Michael R.; Gregory, Jonathan; Colman, Robert; Andrews, Timothy

2018-02-01

Transient climate response (TCR), transient response at 140 years (T140), and equilibrium climate sensitivity (ECS) indices are intended as benchmarks for comparing the magnitude of climate response projected by climate models. It is generally assumed that TCR or T140 would explain more variability between models than ECS for temperature change over the 21st century, since this timescale is the realm of transient climate change. Here we find that TCR explains more variability across Coupled Model Intercomparison Project phase 5 than ECS for global temperature change since preindustrial, for 50 or 100 year global trends up to the present, and for projected change under representative concentration pathways in regions of delayed warming such as the Southern Ocean. However, unexpectedly, we find that ECS correlates higher than TCR for projected change from the present in the global mean and in most regions. This higher correlation does not relate to aerosol forcing, and the physical cause requires further investigation.

On solar geoengineering and climate uncertainty

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacMartin, Douglas; Kravitz, Benjamin S.; Rasch, Philip J.

2015-09-03

Uncertainty in the climate system response has been raised as a concern regarding solar geoengineering. Here we show that model projections of regional climate change outcomes may have greater agreement under solar geoengineering than with CO2 alone. We explore the effects of geoengineering on one source of climate system uncertainty by evaluating the inter-model spread across 12 climate models participating in the Geoengineering Model Intercomparison project (GeoMIP). The model spread in regional temperature and precipitation changes is reduced with CO2 and a solar reduction, in comparison to the case with increased CO2 alone. That is, the intermodel spread in predictionsmore » of climate change and the model spread in the response to solar geoengineering are not additive but rather partially cancel. Furthermore, differences in efficacy explain most of the differences between models in their temperature response to an increase in CO2 that is offset by a solar reduction. These conclusions are important for clarifying geoengineering risks.« less

Inhomogeneous Forcing and Transient Climate Sensitivity

NASA Technical Reports Server (NTRS)

Shindell, Drew T.

2014-01-01

Understanding climate sensitivity is critical to projecting climate change in response to a given forcing scenario. Recent analyses have suggested that transient climate sensitivity is at the low end of the present model range taking into account the reduced warming rates during the past 10-15 years during which forcing has increased markedly. In contrast, comparisons of modelled feedback processes with observations indicate that the most realistic models have higher sensitivities. Here I analyse results from recent climate modelling intercomparison projects to demonstrate that transient climate sensitivity to historical aerosols and ozone is substantially greater than the transient climate sensitivity to CO2. This enhanced sensitivity is primarily caused by more of the forcing being located at Northern Hemisphere middle to high latitudes where it triggers more rapid land responses and stronger feedbacks. I find that accounting for this enhancement largely reconciles the two sets of results, and I conclude that the lowest end of the range of transient climate response to CO2 in present models and assessments (less than 1.3 C) is very unlikely.

44 CFR 352.26 - Arrangements for Federal response in the licensee offsite emergency response plan.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Federal response in the licensee offsite emergency response plan. Federal agencies may be called upon to assist the licensee in developing a licensee offsite emergency response plan in areas such as: (a... response in the licensee offsite emergency response plan. 352.26 Section 352.26 Emergency Management and...

44 CFR 352.26 - Arrangements for Federal response in the licensee offsite emergency response plan.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Federal response in the licensee offsite emergency response plan. Federal agencies may be called upon to assist the licensee in developing a licensee offsite emergency response plan in areas such as: (a... response in the licensee offsite emergency response plan. 352.26 Section 352.26 Emergency Management and...

44 CFR 352.26 - Arrangements for Federal response in the licensee offsite emergency response plan.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Federal response in the licensee offsite emergency response plan. Federal agencies may be called upon to assist the licensee in developing a licensee offsite emergency response plan in areas such as: (a... response in the licensee offsite emergency response plan. 352.26 Section 352.26 Emergency Management and...

44 CFR 352.26 - Arrangements for Federal response in the licensee offsite emergency response plan.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Federal response in the licensee offsite emergency response plan. Federal agencies may be called upon to assist the licensee in developing a licensee offsite emergency response plan in areas such as: (a... response in the licensee offsite emergency response plan. 352.26 Section 352.26 Emergency Management and...

GMMIP (v1.0) contribution to CMIP6: Global Monsoons Model Inter-comparison Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Tianjun; Turner, Andrew G.; Kinter, James L.

The Global Monsoons Model Inter-comparison Project (GMMIP) has been endorsed by the panel of Coupled Model Inter-comparison Project (CMIP) as one of the participating model inter-comparison projects (MIPs) in the sixth phase of CMIP (CMIP6). The focus of GMMIP is on monsoon climatology, variability, prediction and projection, which is relevant to four of the “Grand Challenges” proposed by the World Climate Research Programme. At present, 21 international modeling groups are committed to joining GMMIP. This overview paper introduces the motivation behind GMMIP and the scientific questions it intends to answer. Three tiers of experiments, of decreasing priority, are designed to examinemore » (a) model skill in simulating the climatology and interannual-to-multidecadal variability of global monsoons forced by the sea surface temperature during historical climate period; (b) the roles of the Interdecadal Pacific Oscillation and Atlantic Multidecadal Oscillation in driving variations of the global and regional monsoons; and (c) the effects of large orographic terrain on the establishment of the monsoons. The outputs of the CMIP6 Diagnostic, Evaluation and Characterization of Klima experiments (DECK), “historical” simulation and endorsed MIPs will also be used in the diagnostic analysis of GMMIP to give a comprehensive understanding of the roles played by different external forcings, potential improvements in the simulation of monsoon rainfall at high resolution and reproducibility at decadal timescales. The implementation of GMMIP will improve our understanding of the fundamental physics of changes in the global and regional monsoons over the past 140 years and ultimately benefit monsoons prediction and projection in the current century.« less

Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

NASA Astrophysics Data System (ADS)

M. Noor, Noramaliza; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D. A.

2017-11-01

Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 μm core diameter Ge-doped silica fibres (Ge-9 μm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%.

Intercomparison of mid latitude storm diagnostics (IMILAST) - synthesis of project results

NASA Astrophysics Data System (ADS)

Neu, Urs

2017-04-01

The analysis of the occurrence of mid-latitude storms is of great socio-economical interest due to their vast and destructive impacts. However, a unique definition of cyclones is missing, and therefore the definition of what a cyclone is as well as quantifying its strength contains subjective choices. Existing automatic cyclone identification and tracking algorithms are based on different definitions and use diverse characteristics, e.g. data transformation, metrics used for cyclone identification, cyclone identification procedures or tracking methods. The project IMILAST systematically compares different cyclone detection and tracking methods, with the aim to comprehensively assess the influence of different algorithms on cyclone climatologies, temporal trends of frequency, strength or other characteristics of cyclones and thus quantify systematic uncertainties in mid-latitudinal storm identification and tracking. The three main intercomparison experiments used the ERA-interim reanalysis as a common input data set and focused on differences between the methods with respect to number, track density, life cycle characteristics, and trend patterns on the one hand and potential differences of the long-term climate change signal of cyclonic activity between the methods on the other hand. For the third experiment, the intercomparison period has been extended to a 30 year period from 1979 to 2009 and focuses on more specific aspects, such as parameter sensitivities, the comparison of automated to manual tracking sets, regional analysis (regional trends, Arctic and Antarctic cyclones, cyclones in the Mediterranean) or specific phenomena like splitting and merging of cyclones. In addition, the representation of storms and their characteristics in reanalysis data sets is examined to further enhance the knowledge on uncertainties related to storm occurrence. This poster presents a synthesis of the main results from the intercomparison activities within IMILAST.

IPRT polarized radiative transfer model intercomparison project - Three-dimensional test cases (phase B)

NASA Astrophysics Data System (ADS)

Emde, Claudia; Barlakas, Vasileios; Cornet, Céline; Evans, Frank; Wang, Zhen; Labonotte, Laurent C.; Macke, Andreas; Mayer, Bernhard; Wendisch, Manfred

2018-04-01

Initially unpolarized solar radiation becomes polarized by scattering in the Earth's atmosphere. In particular molecular scattering (Rayleigh scattering) polarizes electromagnetic radiation, but also scattering of radiation at aerosols, cloud droplets (Mie scattering) and ice crystals polarizes. Each atmospheric constituent produces a characteristic polarization signal, thus spectro-polarimetric measurements are frequently employed for remote sensing of aerosol and cloud properties. Retrieval algorithms require efficient radiative transfer models. Usually, these apply the plane-parallel approximation (PPA), assuming that the atmosphere consists of horizontally homogeneous layers. This allows to solve the vector radiative transfer equation (VRTE) efficiently. For remote sensing applications, the radiance is considered constant over the instantaneous field-of-view of the instrument and each sensor element is treated independently in plane-parallel approximation, neglecting horizontal radiation transport between adjacent pixels (Independent Pixel Approximation, IPA). In order to estimate the errors due to the IPA approximation, three-dimensional (3D) vector radiative transfer models are required. So far, only a few such models exist. Therefore, the International Polarized Radiative Transfer (IPRT) working group of the International Radiation Commission (IRC) has initiated a model intercomparison project in order to provide benchmark results for polarized radiative transfer. The group has already performed an intercomparison for one-dimensional (1D) multi-layer test cases [phase A, 1]. This paper presents the continuation of the intercomparison project (phase B) for 2D and 3D test cases: a step cloud, a cubic cloud, and a more realistic scenario including a 3D cloud field generated by a Large Eddy Simulation (LES) model and typical background aerosols. The commonly established benchmark results for 3D polarized radiative transfer are available at the IPRT website (http://www.meteo.physik.uni-muenchen.de/ iprt).

Elemental composition of ambient aerosols measured with high temporal resolution using an online XRF spectrometer

NASA Astrophysics Data System (ADS)

Furger, Markus; Cruz Minguillón, María; Yadav, Varun; Slowik, Jay G.; Hüglin, Christoph; Fröhlich, Roman; Petterson, Krag; Baltensperger, Urs; Prévôt, André S. H.

2017-06-01

The Xact 625 Ambient Metals Monitor was tested during a 3-week field campaign at the rural, traffic-influenced site Härkingen in Switzerland during the summer of 2015. The field campaign encompassed the Swiss National Day fireworks event, providing increased concentrations and unique chemical signatures compared to non-fireworks (or background) periods. The objective was to evaluate the data quality by intercomparison with other independent measurements and test its applicability for aerosol source quantification. The Xact was configured to measure 24 elements in PM10 with 1 h time resolution. Data quality was evaluated for 10 24 h averages of Xact data by intercomparison with 24 h PM10 filter data analysed with ICP-OES for major elements, ICP-MS for trace elements, and gold amalgamation atomic absorption spectrometry for Hg. Ten elements (S, K, Ca, Ti, Mn, Fe, Cu, Zn, Ba, Pb) showed excellent correlation between the compared methods, with r2 values ≥ 0.95. However, the slopes of the regressions between Xact 625 and ICP data varied from 0.97 to 1.8 (average 1.28) and thus indicated generally higher Xact elemental concentrations than ICP for these elements. Possible reasons for these differences are discussed, but further investigations are needed. For the remaining elements no conclusions could be drawn about their quantification for various reasons, mainly detection limit issues. An indirect intercomparison of hourly values was performed for the fireworks peak, which brought good agreement of total masses when the Xact data were corrected with the regressions from the 24 h value intercomparison. The results demonstrate that multi-metal characterization at high-time-resolution capability of Xact is a valuable and practical tool for ambient monitoring.

Rising temperatures reduce global wheat production

NASA Astrophysics Data System (ADS)

Asseng, S.; Ewert, F.; Martre, P.; Rötter, R. P.; Lobell, D. B.; Cammarano, D.; Kimball, B. A.; Ottman, M. J.; Wall, G. W.; White, J. W.; Reynolds, M. P.; Alderman, P. D.; Prasad, P. V. V.; Aggarwal, P. K.; Anothai, J.; Basso, B.; Biernath, C.; Challinor, A. J.; de Sanctis, G.; Doltra, J.; Fereres, E.; Garcia-Vila, M.; Gayler, S.; Hoogenboom, G.; Hunt, L. A.; Izaurralde, R. C.; Jabloun, M.; Jones, C. D.; Kersebaum, K. C.; Koehler, A.-K.; Müller, C.; Naresh Kumar, S.; Nendel, C.; O'Leary, G.; Olesen, J. E.; Palosuo, T.; Priesack, E.; Eyshi Rezaei, E.; Ruane, A. C.; Semenov, M. A.; Shcherbak, I.; Stöckle, C.; Stratonovitch, P.; Streck, T.; Supit, I.; Tao, F.; Thorburn, P. J.; Waha, K.; Wang, E.; Wallach, D.; Wolf, J.; Zhao, Z.; Zhu, Y.

2015-02-01

Crop models are essential tools for assessing the threat of climate change to local and global food production. Present models used to predict wheat grain yield are highly uncertain when simulating how crops respond to temperature. Here we systematically tested 30 different wheat crop models of the Agricultural Model Intercomparison and Improvement Project against field experiments in which growing season mean temperatures ranged from 15 °C to 32 °C, including experiments with artificial heating. Many models simulated yields well, but were less accurate at higher temperatures. The model ensemble median was consistently more accurate in simulating the crop temperature response than any single model, regardless of the input information used. Extrapolating the model ensemble temperature response indicates that warming is already slowing yield gains at a majority of wheat-growing locations. Global wheat production is estimated to fall by 6% for each °C of further temperature increase and become more variable over space and time.

Responses of East Asian Summer Monsoon to Natural and Anthropogenic Forcings in the 17 Latest CMIP5 Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Fengfei; Zhou, Tianjun; Qian, Yun

2014-01-31

In this study, we examined the responses of East Asian Summer Monsoon (EASM) to natural (solar variability and volcanic aerosols) and anthropogenic (greenhouse gasses and aerosols) forcings simulated in the 17 latest Coupled Model Intercomparison Program phase 5 (CMIP5) models with 105 realizations. The observed weakening trend of low-level EASM circulation during 1958-2001 is partly reproduced under all-forcing runs. A comparison of separate forcing experiments reveals that the aerosol-forcing plays a primary role in driving the weakened low-level monsoon circulation. The preferential cooling over continental East Asia caused by aerosol affects the monsoon circulation through reducing the land-sea thermal contrastmore » and results in higher sea level pressure over northern China. In the upper-level, both natural-forcing and aerosol-forcing contribute to the observed southward shift of East Asian subtropical jet through changing the meridional temperature gradient.« less

Rising Temperatures Reduce Global Wheat Production

NASA Technical Reports Server (NTRS)

Asseng, S.; Ewert, F.; Martre, P.; Rötter, R. P.; Lobell, D. B.; Cammarano, D.; Kimball, B. A.; Ottman, M. J.; Wall, G. W.; White, J. W.;

Attribution of Observed Streamflow Changes in Key British Columbia Drainage Basins

NASA Astrophysics Data System (ADS)

Najafi, Mohammad Reza; Zwiers, Francis W.; Gillett, Nathan P.

2017-11-01

We study the observed decline in summer streamflow in four key river basins in British Columbia (BC), Canada, using a formal detection and attribution (D&A) analysis procedure. Reconstructed and simulated streamflow is generated using the semidistributed variable infiltration capacity hydrologic model, which is driven by 1/16° gridded observations and downscaled climate model data from the Coupled Model Intercomparison Project phase 5 (CMIP5), respectively. The internal variability of the regional hydrologic components using 5100 years of streamflow was simulated using CMIP5 preindustrial control runs. Results show that the observed changes in summer streamflow are inconsistent with simulations representing the responses to natural forcing factors alone, while the response to anthropogenic and natural forcing factors combined is detected in these changes. A two-signal D&A analysis indicates that the effects of anthropogenic (ANT) forcing factors are discernable from natural forcing in BC, albeit with large uncertainties.

SIMBIOS Project

NASA Technical Reports Server (NTRS)

Fargion, Giulietta S.; McClain, Charles R.; Busalacchi, Antonio J. (Technical Monitor)

2001-01-01

The purpose of this technical report is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, NASA Research Announcement (NRAI) research status, satellite data processing, data product validation, and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project.

Making Sense of Palaeoclimate Sensitivity

NASA Technical Reports Server (NTRS)

Rohling, E. J.; Sluijs, A.; DeConto, R.; Drijfhout, S. S.; Fedorov, A.; Foster, G. L.; Ganopolski, A.; Hansen, J.; Honisch, B.; Hooghiemstra, H.;

EPR dosimetry in a mixed neutron and gamma radiation field.

PubMed

Trompier, F; Fattibene, P; Tikunov, D; Bartolotta, A; Carosi, A; Doca, M C

2004-01-01

Suitability of Electron Paramagnetic Resonance (EPR) spectroscopy for criticality dosimetry was evaluated for tooth enamel, mannose and alanine pellets during the 'international intercomparison of criticality dosimetry techniques' at the SILENE reactor held in Valduc in June 2002, France. These three materials were irradiated in neutron and gamma-ray fields of various relative intensities and spectral distributions in order to evaluate their neutron sensitivity. The neutron response was found to be around 10% for tooth enamel, 45% for mannose and between 40 and 90% for alanine pellets according their type. According to the IAEA recommendations on the early estimate of criticality accident absorbed dose, analyzed results show the EPR potentiality and complementarity with regular criticality techniques.

Consistency of climate change projections from multiple global and regional model intercomparison projects

NASA Astrophysics Data System (ADS)

Fernández, J.; Frías, M. D.; Cabos, W. D.; Cofiño, A. S.; Domínguez, M.; Fita, L.; Gaertner, M. A.; García-Díez, M.; Gutiérrez, J. M.; Jiménez-Guerrero, P.; Liguori, G.; Montávez, J. P.; Romera, R.; Sánchez, E.

2018-03-01

We present an unprecedented ensemble of 196 future climate projections arising from different global and regional model intercomparison projects (MIPs): CMIP3, CMIP5, ENSEMBLES, ESCENA, EURO- and Med-CORDEX. This multi-MIP ensemble includes all regional climate model (RCM) projections publicly available to date, along with their driving global climate models (GCMs). We illustrate consistent and conflicting messages using continental Spain and the Balearic Islands as target region. The study considers near future (2021-2050) changes and their dependence on several uncertainty sources sampled in the multi-MIP ensemble: GCM, future scenario, internal variability, RCM, and spatial resolution. This initial work focuses on mean seasonal precipitation and temperature changes. The results show that the potential GCM-RCM combinations have been explored very unevenly, with favoured GCMs and large ensembles of a few RCMs that do not respond to any ensemble design. Therefore, the grand-ensemble is weighted towards a few models. The selection of a balanced, credible sub-ensemble is challenged in this study by illustrating several conflicting responses between the RCM and its driving GCM and among different RCMs. Sub-ensembles from different initiatives are dominated by different uncertainty sources, being the driving GCM the main contributor to uncertainty in the grand-ensemble. For this analysis of the near future changes, the emission scenario does not lead to a strong uncertainty. Despite the extra computational effort, for mean seasonal changes, the increase in resolution does not lead to important changes.

LS3MIP (v1.0) Contribution to CMIP6: The Land Surface, Snow and Soil Moisture Model Intercomparison Project Aims, Setup and Expected Outcome.

NASA Technical Reports Server (NTRS)

Van Den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard; Seneviratne, Sonia I.; Derksen, Chris; Oki, Taikan; Douville, Herve; Colin, Jeanne; Ducharne, Agnes; Cheruy, Frederique;

The Detection and Attribution Model Intercomparison Project (DAMIP v1.0)contribution to CMIP6

DOE PAGES

Gillett, Nathan P.; Shiogama, Hideo; Funke, Bernd; ...

2016-10-18

Detection and attribution (D&A) simulations were important components of CMIP5 and underpinned the climate change detection and attribution assessments of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. The primary goals of the Detection and Attribution Model Intercomparison Project (DAMIP) are to facilitate improved estimation of the contributions of anthropogenic and natural forcing changes to observed global warming as well as to observed global and regional changes in other climate variables; to contribute to the estimation of how historical emissions have altered and are altering contemporary climate risk; and to facilitate improved observationally constrained projections of futuremore » climate change. D&A studies typically require unforced control simulations and historical simulations including all major anthropogenic and natural forcings. Such simulations will be carried out as part of the DECK and the CMIP6 historical simulation. In addition D&A studies require simulations covering the historical period driven by individual forcings or subsets of forcings only: such simulations are proposed here. Key novel features of the experimental design presented here include firstly new historical simulations with aerosols-only, stratospheric-ozone-only, CO2-only, solar-only, and volcanic-only forcing, facilitating an improved estimation of the climate response to individual forcing, secondly future single forcing experiments, allowing observationally constrained projections of future climate change, and thirdly an experimental design which allows models with and without coupled atmospheric chemistry to be compared on an equal footing.« less

ENSO-Related Precipitation and Its Statistical Relationship with the Walker Circulation Trend in CMIP5 AMIP Models

DOE PAGES

Yim, Bo; Yeh, Sang -Wook; Sohn, Byung -Ju

2016-01-29

Observational evidence shows that the Walker circulation (WC) in the tropical Pacific has strengthened in recent decades. In this study, we examine the WC trend for 1979–2005 and its relationship with the precipitation associated with the El Niño Southern Oscillation (ENSO) using the sea surface temperature (SST)-constrained Atmospheric Model Intercomparison Project (AMIP) simulations of the Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models. All of the 29 models show a strengthening of the WC trend in response to an increase in the SST zonal gradient along the equator. Despite the same SST-constrained AMIP simulations, however, a large diversity ismore » found among the CMIP5 climate models in the magnitude of the WC trend. The relationship between the WC trend and precipitation anomalies (PRCPAs) associated with ENSO (ENSO-related PRCPAs) shows that the longitudinal position of the ENSO-related PRCPAs in the western tropical Pacific is closely related to the magnitude of the WC trend. Specifically, it is found that the strengthening of the WC trend is large (small) in the CMIP5 AMIP simulations in which the ENSO-related PRCPAs are located relatively westward (eastward) in the western tropical Pacific. Furthermore, the zonal shift of the ENSO-related precipitation in the western tropical Pacific, which is associated with the climatological mean precipitation in the tropical Pacific, could play an important role in modifying the WC trend in the CMIP5 climate models.« less

The Detection and Attribution Model Intercomparison Project (DAMIP v1.0) contribution to CMIP6

NASA Astrophysics Data System (ADS)

Gillett, Nathan P.; Shiogama, Hideo; Funke, Bernd; Hegerl, Gabriele; Knutti, Reto; Matthes, Katja; Santer, Benjamin D.; Stone, Daithi; Tebaldi, Claudia

2016-10-01

Detection and attribution (D&A) simulations were important components of CMIP5 and underpinned the climate change detection and attribution assessments of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. The primary goals of the Detection and Attribution Model Intercomparison Project (DAMIP) are to facilitate improved estimation of the contributions of anthropogenic and natural forcing changes to observed global warming as well as to observed global and regional changes in other climate variables; to contribute to the estimation of how historical emissions have altered and are altering contemporary climate risk; and to facilitate improved observationally constrained projections of future climate change. D&A studies typically require unforced control simulations and historical simulations including all major anthropogenic and natural forcings. Such simulations will be carried out as part of the DECK and the CMIP6 historical simulation. In addition D&A studies require simulations covering the historical period driven by individual forcings or subsets of forcings only: such simulations are proposed here. Key novel features of the experimental design presented here include firstly new historical simulations with aerosols-only, stratospheric-ozone-only, CO2-only, solar-only, and volcanic-only forcing, facilitating an improved estimation of the climate response to individual forcing, secondly future single forcing experiments, allowing observationally constrained projections of future climate change, and thirdly an experimental design which allows models with and without coupled atmospheric chemistry to be compared on an equal footing.

LS3MIP (v1.0) contribution to CMIP6: the Land Surface, Snow and Soilmoisture Model Intercomparison Project – aims, setup and expected outcome

DOE PAGES

van den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard; ...

2016-08-24

The Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP) is designed to provide a comprehensive assessment of land surface, snow and soil moisture feedbacks on climate variability and climate change, and to diagnose systematic biases in the land modules of current Earth system models (ESMs). Furthermore, the solid and liquid water stored at the land surface has a large influence on the regional climate, its variability and predictability, including effects on the energy, water and carbon cycles. Notably, snow and soil moisture affect surface radiation and flux partitioning properties, moisture storage and land surface memory. They both stronglymore » affect atmospheric conditions, in particular surface air temperature and precipitation, but also large-scale circulation patterns. But, models show divergent responses and representations of these feedbacks as well as systematic biases in the underlying processes. LS3MIP will provide the means to quantify the associated uncertainties and better constrain climate change projections, which is of particular interest for highly vulnerable regions (densely populated areas, agricultural regions, the Arctic, semi-arid and other sensitive terrestrial ecosystems). The experiments are subdivided in two components, the first addressing systematic land biases in offline mode (“LMIP”, building upon the 3rd phase of Global Soil Wetness Project; GSWP3) and the second addressing land feedbacks attributed to soil moisture and snow in an integrated framework (“LFMIP”, building upon the GLACE-CMIP blueprint).« less

LS3MIP (v1.0) contribution to CMIP6: the Land Surface, Snow and Soilmoisture Model Intercomparison Project – aims, setup and expected outcome

DOE Office of Scientific and Technical Information (OSTI.GOV)

van den Hurk, Bart; Kim, Hyungjun; Krinner, Gerhard

The Land Surface, Snow and Soil Moisture Model Intercomparison Project (LS3MIP) is designed to provide a comprehensive assessment of land surface, snow and soil moisture feedbacks on climate variability and climate change, and to diagnose systematic biases in the land modules of current Earth system models (ESMs). Furthermore, the solid and liquid water stored at the land surface has a large influence on the regional climate, its variability and predictability, including effects on the energy, water and carbon cycles. Notably, snow and soil moisture affect surface radiation and flux partitioning properties, moisture storage and land surface memory. They both stronglymore » affect atmospheric conditions, in particular surface air temperature and precipitation, but also large-scale circulation patterns. But, models show divergent responses and representations of these feedbacks as well as systematic biases in the underlying processes. LS3MIP will provide the means to quantify the associated uncertainties and better constrain climate change projections, which is of particular interest for highly vulnerable regions (densely populated areas, agricultural regions, the Arctic, semi-arid and other sensitive terrestrial ecosystems). The experiments are subdivided in two components, the first addressing systematic land biases in offline mode (“LMIP”, building upon the 3rd phase of Global Soil Wetness Project; GSWP3) and the second addressing land feedbacks attributed to soil moisture and snow in an integrated framework (“LFMIP”, building upon the GLACE-CMIP blueprint).« less

A first-order analysis of the potential role of CO2 fertilization to affect the global carbon budget: A comparison of four terrestrial biosphere models

USGS Publications Warehouse

Kicklighter, D.W.; Bruno, M.; Donges, S.; Esser, G.; Heimann, Martin; Helfrich, J.; Ift, F.; Joos, F.; Kaduk, J.; Kohlmaier, G.H.; McGuire, A.D.; Melillo, J.M.; Meyer, R.; Moore, B.; Nadler, A.; Prentice, I.C.; Sauf, W.; Schloss, A.L.; Sitch, S.; Wittenberg, U.; Wurth, G.

1999-01-01

We compared the simulated responses of net primary production, heterotrophic respiration, net ecosystem production and carbon storage in natural terrestrial ecosystems to historical (1765 to 1990) and projected (1990 to 2300) changes of atmospheric CO2 concentration of four terrestrial biosphere models: the Bern model, the Frankfurt Biosphere Model (FBM), the High-Resolution Biosphere Model (HRBM) and the Terrestrial Ecosystem Model (TEM). The results of the model intercomparison suggest that CO2 fertilization of natural terrestrial vegetation has the potential to account for a large fraction of the so-called 'missing carbon sink' of 2.0 Pg C in 1990. Estimates of this potential are reduced when the models incorporate the concept that CO2 fertilization can be limited by nutrient availability. Although the model estimates differ on the potential size (126 to 461 Pg C) of the future terrestrial sink caused by CO2 fertilization, the results of the four models suggest that natural terrestrial ecosystems will have a limited capacity to act as a sink of atmospheric CO2 in the future as a result of physiological constraints and nutrient constraints on NPP. All the spatially explicit models estimate a carbon sink in both tropical and northern temperate regions, but the strength of these sinks varies over time. Differences in the simulated response of terrestrial ecosystems to CO2 fertilization among the models in this intercomparison study reflect the fact that the models have highlighted different aspects of the effect of CO2 fertilization on carbon dynamics of natural terrestrial ecosystems including feedback mechanisms. As interactions with nitrogen fertilization, climate change and forest regrowth may play an important role in simulating the response of terrestrial ecosystems to CO2 fertilization, these factors should be included in future analyses. Improvements in spatially explicit data sets, whole-ecosystems experiments and the availability of net carbon exchange measurements across the globe will also help to improve future evaluations of the role of CO2 fertilization on terrestrial carbon storage.

The Flux-Anomaly-Forced Model Intercomparison Project (FAFMIP) Contribution to CMIP6: Investigation of Sea-Level and Ocean Climate Change in Response to CO2 Forcing

NASA Technical Reports Server (NTRS)

Gregory, Jonathan M.; Bouttes, Nathaelle; Griffies, Stephen M.; Haak, Helmuth; Hurlin, William J.; Jungclaus, Johann; Kelley, Maxwell; Lee, Warren G.; Marshall, John; Romanou, Anastasia;

The Latest SORCE Solar Spectral Irradiance Data Release: Inter-Comparison and a First Look at TSIS SIM Measurement.

NASA Astrophysics Data System (ADS)

Beland, S.; Sandoval, L.; Vanier, B.; Elliott, J.; Harder, J. W.; Snow, M. A.; Woods, T. N.; Richard, E. C.; Pilewskie, P.

2017-12-01

The Spectral Irradiance Monitor (SIM), the SOLar STellar Irradiance Comparison Experiment (SOLSTICE), and the XUV Photometer System (XPS) instruments on board the Solar Radiation and Climate Experiment (SORCE) mission have been taking daily Solar spectral irradiance (SSI) measurements since April 2003. We present the latest data releases from these instruments, describing the improvements in the new datasets and the trends measured during Solar cycles 23 and 24. An inter-comparison of the SSI over the overlapping wavelengths for SIM and SOLSTICE is presented as well as, if the data is available, a comparison with the first light measurements from TSIS-SIM.

NASA Giovanni Portals for NLDAS/GLDAS Online Visualization, Analysis, and Intercomparison

NASA Technical Reports Server (NTRS)

Rui, Hualan; Teng, William L.; Vollmer, Bruce; Mocko, David M.; Beaudoing, Hiroko Kato; Rodell, Matthew

2011-01-01

The North American Land Data Assimilation System (NLDAS) and Global Land Data Assimilation System (GLDAS) are generating a series of land surface forcing (e.g., precipitation, surface meteorology, and radiation), state (e.g., soil moisture and temperature, and snow), and flux (e.g., evaporation and sensible heat flux) products, simulated by several land surface models. To date, NLDAS and GLDAS have generated more than 30 (1979 - present) and 60 (1948 - present) years of data, respectively. To further facilitate data accessibility and utilization, three new portals in the NASA Giovanni system have been made available for NLDAS and GLDAS online visualization, analysis, and intercomparison.

Ozone profile intercomparison based on simultaneous observations between 20 and 40 km

NASA Technical Reports Server (NTRS)

Aimedieu, P.; Krueger, A. J.; Robbins, D. E.; Simon, P. C.

1983-01-01

The vertical distribution of stratospheric ozone has been simultaneously measured by means of five different instruments carried on the same balloon payload. The launches were performed from Gap during the intercomparison campaign conducted in June 1981 in southern France. Data obtained between altitudes of 20 and 40 km are compared and discussed. Vertical profiles deduced from Electrochemical Concentration Cell sondes launched from the same location by small balloons and from short Umkehr measurements made at Mt Chiran (France) are also included in this comparison. Systematic differences of the order of 20 percent between ozone profiles deduced from solar u.v. absorption and in situ techniques are found.

Impact of Spatial Scales on the Intercomparison of Climate Scenarios

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Wei; Steptoe, Michael; Chang, Zheng

2017-01-01

Scenario analysis has been widely applied in climate science to understand the impact of climate change on the future human environment, but intercomparison and similarity analysis of different climate scenarios based on multiple simulation runs remain challenging. Although spatial heterogeneity plays a key role in modeling climate and human systems, little research has been performed to understand the impact of spatial variations and scales on similarity analysis of climate scenarios. To address this issue, the authors developed a geovisual analytics framework that lets users perform similarity analysis of climate scenarios from the Global Change Assessment Model (GCAM) using a hierarchicalmore » clustering approach.« less

Past and future weather-induced risk in crop production

NASA Astrophysics Data System (ADS)

Elliott, J. W.; Glotter, M.; Russo, T. A.; Sahoo, S.; Foster, I.; Benton, T.; Mueller, C.

2016-12-01

Drought-induced agricultural loss is one of the most costly impacts of extreme weather and may harm more people than any other consequence of climate change. Improvements in farming practices have dramatically increased crop productivity, but yields today are still tightly linked to climate variation. We report here on a number of recent studies evaluating extreme event risk and impacts under historical and near future conditions, including studies conducted as part of the Agricultural Modeling Intercomparison and Improvement Project (AgMIP), the Inter-Sectoral Impacts Model Intercomparison Project (ISI-MIP) and the UK-US Taskforce on Extreme Weather and Global Food System Resilience.

The Agricultural Model Intercomparison and Improvement Project: Phase I Activities by a Global Community of Science. Chapter 1

NASA Technical Reports Server (NTRS)

Rosenzweig, Cynthia E.; Jones, James W.; Hatfield, Jerry L.; Antle, John M.; Ruane, Alexander C.; Mutter, Carolyn Z.

2015-01-01

The Agricultural Model Intercomparison and Improvement Project (AgMIP) was founded in 2010. Its mission is to improve substantially the characterization of world food security as affected by climate variability and change, and to enhance adaptation capacity in both developing and developed countries. The objectives of AgMIP are to: Incorporate state-of-the-art climate, crop/livestock, and agricultural economic model improvements into coordinated multi-model regional and global assessments of future climate impacts and adaptation and other key aspects of the food system. Utilize multiple models, scenarios, locations, crops/livestock, and participants to explore uncertainty and the impact of data and methodological choices. Collaborate with regional experts in agronomy, animal sciences, economics, and climate to build a strong basis for model applications, addressing key climate related questions and sustainable intensification farming systems. Improve scientific and adaptive capacity in modeling for major agricultural regions in the developing and developed world, with a focus on vulnerable regions. Improve agricultural data and enhance data-sharing based on their intercomparison and evaluation using best scientific practices. Develop modeling frameworks to identify and evaluate promising adaptation technologies and policies and to prioritize strategies.

Constraints and potentials of future irrigation water availability on agricultural production under climate change.

PubMed

Elliott, Joshua; Deryng, Delphine; Müller, Christoph; Frieler, Katja; Konzmann, Markus; Gerten, Dieter; Glotter, Michael; Flörke, Martina; Wada, Yoshihide; Best, Neil; Eisner, Stephanie; Fekete, Balázs M; Folberth, Christian; Foster, Ian; Gosling, Simon N; Haddeland, Ingjerd; Khabarov, Nikolay; Ludwig, Fulco; Masaki, Yoshimitsu; Olin, Stefan; Rosenzweig, Cynthia; Ruane, Alex C; Satoh, Yusuke; Schmid, Erwin; Stacke, Tobias; Tang, Qiuhong; Wisser, Dominik

2014-03-04

We compare ensembles of water supply and demand projections from 10 global hydrological models and six global gridded crop models. These are produced as part of the Inter-Sectoral Impacts Model Intercomparison Project, with coordination from the Agricultural Model Intercomparison and Improvement Project, and driven by outputs of general circulation models run under representative concentration pathway 8.5 as part of the Fifth Coupled Model Intercomparison Project. Models project that direct climate impacts to maize, soybean, wheat, and rice involve losses of 400-1,400 Pcal (8-24% of present-day total) when CO2 fertilization effects are accounted for or 1,400-2,600 Pcal (24-43%) otherwise. Freshwater limitations in some irrigated regions (western United States; China; and West, South, and Central Asia) could necessitate the reversion of 20-60 Mha of cropland from irrigated to rainfed management by end-of-century, and a further loss of 600-2,900 Pcal of food production. In other regions (northern/eastern United States, parts of South America, much of Europe, and South East Asia) surplus water supply could in principle support a net increase in irrigation, although substantial investments in irrigation infrastructure would be required.

Airborne intercomparison of nitric oxide measurement techniques

NASA Technical Reports Server (NTRS)

Hoell, James M., Jr.; Gregory, Gerald L.; Mcdougal, David S.; Torres, Arnold L.; Davis, Douglas D.

1987-01-01

Results from an airborne intercomparison of techniques to measure tropospheric levels of nitric oxide (NO) are discussed. The intercomparison was part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and was conducted during missions flown in the fall of 1983 and spring of 1984. Instruments intercompared included a laser-induced fluorescence (LIF) system and two chemiluminescence instruments (CL). NO mixing ratios from below 5 pptv (parts per trillion by volume) to greater than 100 pptv were reported, with the majority less than 20 pptv. Good correlation was observed between the measurements reported by the CL and LIF techniques. The general level of agreement observed for the ensemble of measurements obtained during the two missions provides the basis from which one can conclude that equally 'valid' measurements of background levels of NO can be expected from either CL or LIF instruments. At the same time the periods of disagreement that were observed between the CL and LIF instruments as well as between the two CL instruments highlight the difficulty of obtaining reliable measurements with NO mixing ratios in the 5-20 pptv range and emphasize the vigilance that should be maintained in future NO measurements.

Nuclear accident dosimetry intercomparison studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sims, C.S.

1989-09-01

Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shieldedmore » spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry.« less

Economic impacts of climate change on agriculture: the AgMIP approach

NASA Astrophysics Data System (ADS)

Delincé, Jacques; Ciaian, Pavel; Witzke, Heinz-Peter

2015-01-01

The current paper investigates the long-term global impacts on crop productivity under different climate scenarios using the AgMIP approach (Agricultural Model Intercomparison and Improvement Project). The paper provides horizontal model intercomparison from 11 economic models as well as a more detailed analysis of the simulated effects from the Common Agricultural Policy Regionalized Impact (CAPRI) model to systematically compare its performance with other AgMIP models and specifically for the Chinese agriculture. CAPRI is a comparative static partial equilibrium model extensively used for medium and long-term economic and environmental policy impact applications. The results indicate that, at the global level, the climate change will cause an agricultural productivity decrease (between -2% and -15% by 2050), a food price increase (between 1.3% and 56%) and an expansion of cultivated area (between 1% and 4%) by 2050. The results for China indicate that the climate change effects tend to be smaller than the global impacts. The CAPRI-simulated effects are, in general, close to the median across all AgMIP models. Model intercomparison analyses reveal consistency in terms of direction of change to climate change but relatively strong heterogeneity in the magnitude of the effects between models.

Long History of IAM Comparisons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Steven J.; Clarke, Leon E.; Edmonds, James A.

2015-04-23

Correspondence to editor: We agree with the editors that the assumptions behind models of all types, including integrated assessment models (IAMs), should be as transparent as possible. The editors were in error, however, when they implied that the IAM community is just “now emulating the efforts of climate researchers by instigating their own model inter-comparison projects (MIPs).” In fact, model comparisons for integrated assessment and climate models followed a remarkably similar trajectory. Early General Circulation Model (GCM) comparison efforts, evolved to the first Atmospheric Model Inter-comparison Project (AMIP), which was initiated in the early 1990s. Atmospheric models evolved to coupledmore » atmosphere-ocean models (AOGCMs) and results from the first Coupled Model Inter-Comparison Project (CMIP1) become available about a decade later. Results of first energy model comparison exercise, conducted under the auspices of the Stanford Energy Modeling Forum, were published in 1977. A summary of the first comparison focused on climate change was published in 1993. As energy models were coupled to simple economic and climate models to form IAMs, the first comparison exercise for IAMs (EMF-14) was initiated in 1994, and IAM comparison exercises have been on-going since this time.« less

Models and Measurements Intercomparison 2

NASA Technical Reports Server (NTRS)

Park, Jae H. (Editor); Ko, Malcolm K. W. (Editor); Jackman, Charles H. (Editor); Plumb, R. Alan (Editor); Kaye, Jack A. (Editor); Sage, Karen H. (Editor)

1999-01-01

Models and Measurement Intercomparison II (MM II) summarizes the intercomparison of results from model simulations and observations of stratospheric species. Representatives from twenty-three modeling groups using twenty-nine models participated in these MM II exercises between 1996 and 1999. Twelve of the models were two- dimensional zonal-mean models while seventeen were three-dimensional models. This was an international effort as seven were from outside the United States. Six transport experiments and five chemistry experiments were designed for various models. Models participating in the transport experiments performed simulations of chemically inert tracers providing diagnostics for transport. The chemistry experiments involved simulating the distributions of chemically active trace cases including ozone. The model run conditions for dynamics and chemistry were prescribed in order to minimize the factors that caused differences in the models. The report includes a critical review of the results by the participants and a discussion of the causes of differences between modeled and measured results as well as between results from different models, A sizable effort went into preparation of the database of the observations. This included a new climatology for ozone. The report should help in evaluating the results from various predictive models for assessing humankind perturbations of the stratosphere.

Criticality accident dosimetry systems: an international intercomparison at the SILENE reactor in 2002.

PubMed

Médioni, R; Asselineau, B; Verrey, B; Trompier, F; Itié, C; Texier, C; Muller, H; Pelcot, G; Clairand, I; Jacquet, X; Pochat, J L

2004-01-01

In criticality accident dosimetry and more generally for high dose measurements, special techniques are used to measure separately the gamma ray and neutron components of the dose. To improve these techniques and to check their dosimetry systems (physical and/or biological), a total of 60 laboratories from 29 countries (America, Europe, Asia) participated in an international intercomparaison, which took place in France from 9 to 21 June 2002, at the SILENE reactor in Valduc and at a pure gamma source in Fontenay-aux-Roses. This intercomparison was jointly organised by the IRSN and the CEA with the help of the NEA/OCDE and was partly supported by the European Communities. This paper describes the aim of this intercomparison, the techniques used by the participants and the two radiation sources and their characteristics. The experimental arrangements of the dosemeters for the irradiations in free air or on phantoms are given. Then the dosimetric quantities measured and reported by the participants are summarised, analysed and compared with the reference values. The present paper concerns only the physical dosimetry and essentially experiments performed on the SILENE facility. The results obtained with the biological dosimetry are published in two other papers of this issue.

Metafitting: Weight optimization for least-squares fitting of PTTI data

NASA Technical Reports Server (NTRS)

Douglas, Rob J.; Boulanger, J.-S.

1995-01-01

For precise time intercomparisons between a master frequency standard and a slave time scale, we have found it useful to quantitatively compare different fitting strategies by examining the standard uncertainty in time or average frequency. It is particularly useful when designing procedures which use intermittent intercomparisons, with some parameterized fit used to interpolate or extrapolate from the calibrating intercomparisons. We use the term 'metafitting' for the choices that are made before a fitting procedure is operationally adopted. We present methods for calculating the standard uncertainty for general, weighted least-squares fits and a method for optimizing these weights for a general noise model suitable for many PTTI applications. We present the results of the metafitting of procedures for the use of a regular schedule of (hypothetical) high-accuracy frequency calibration of a maser time scale. We have identified a cumulative series of improvements that give a significant reduction of the expected standard uncertainty, compared to the simplest procedure of resetting the maser synthesizer after each calibration. The metafitting improvements presented include the optimum choice of weights for the calibration runs, optimized over a period of a week or 10 days.

The DeepMIP Contribution to PMIP4: Experimental Design for Model Simulations of the EECO, PETM, and pre-PETM (version 1.0)

NASA Technical Reports Server (NTRS)

Lunt, Daniel J.; Huber, Matthew; Anagnostou, Eleni; Baatsen, Michiel L. J.; Caballero, Rodrigo; DeConto, Rob; Dijkstra, Henk A.; Donnadieu, Yannick; Evans, David; Feng, Ran;

The T-REX valley wind intercomparison project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidli, J; Billings, B J; Burton, R

2008-08-07

An accurate simulation of the evolution of the atmospheric boundary layer is very important, as the evolution of the boundary layer sets the stage for many weather phenomena, such as deep convection. Over mountain areas the evolution of the boundary layer is particularly complex, due to the nonlinear interaction between boundary layer turbulence and thermally-induced mesoscale wind systems, such as the slope and valley winds. As the horizontal resolution of operational forecasts progresses to finer and finer resolution, more and more of the thermally-induced mesoscale wind systems can be explicitly resolved, and it is very timely to document the currentmore » state-of-the-art of mesoscale models at simulating the coupled evolution of the mountain boundary layer and the valley wind system. In this paper we present an intercomparison of valley wind simulations for an idealized valley-plain configuration using eight state-of-the-art mesoscale models with a grid spacing of 1 km. Different sets of three-dimensional simulations are used to explore the effects of varying model dynamical cores and physical parameterizations. This intercomparison project was conducted as part of the Terrain-induced Rotor Experiment (T-REX; Grubisic et al., 2008).« less

Intercomparison of different operational oceanographic forecast products in the CMEMS IBI area

NASA Astrophysics Data System (ADS)

Lorente, Pablo; Sotillo, Marcos G.; Dabrowski, Tomasz; Amo-Baladrón, Arancha; Aznar, Roland; De Pascual, Alvaro; Levier, Bruno; Bowyer, Peter; Cossarini, Gianpiero; Salon, Stefano; Tonani, Marina; Alvarez-Fanjul, Enrique

2017-04-01

The development of skill assessment software packages and dedicated web applications is a relatively novel theme in operational oceanography. Within the CMEMS IBI-MFC, the quality of IBI (Iberia-Biscay-Ireland) forecast products is assessed by means of NARVAL (North Atlantic Regional VALidation) web-based tool. The validation of IBI against independent in situ and remote-sensing measurements is routinely conducted to evaluate model's veracity and prognostic capabilities. Noticeable efforts are in progress to define meaningful skill scores and statistical metrics to quantitatively assess the quality and reliability of the IBI model solution. Likewise, the IBI-MFC compares the IBI forecast products with other model solutions by setting up specific intercomparison exercises on overlapping areas at diverse timescales. In this context, NARVAL web tool already includes a specific module to evaluate strengths and weaknesses of IBI versus other CMEMS operational ocean forecasting systems (OOFSs). In particular, the IBI physical ocean solution is compared against the CMEMS MED and NWS OOFSs. These CMEMS regional services delivered for the Mediterranean and the North West Shelves include data assimilation schemes in their respective operational chains and generate analogous ocean forecast products to the IBI ones. A number of physical parameters (i.e. sea surface temperature, salinity and current velocities) are evaluated through NARVAL on a daily basis in the overlapping areas existing between these three regional systems. NARVAL is currently being updated in order to extend this intercomparison of ocean model parameters to the biogeochemical solutions provided by the aforementioned OOFSs. More specifically, the simulated chlorophyll concentration is evaluated over several subregions of particular concern by using as benchmark the CMEMS satellite-derived observational products. In addition to this IBI comparison against other regional CMEMS products on overlapping areas, a specific intercomparison between the CMEMS GLOBAL solution and the IBI (regional application dynamically embedded in the former) is conducted in order to check its consistency and ability to outperform the parent model solution. Particular emphasis is placed on the comparison of time-series at specified locations (class-2 metrics). The standardized validation methodology presented here is particularly useful and could encompass the intercomparison of the regional application (IBI) and other nested higher resolution models at coastal/shelf scales to quantify the added value of downscaling in local downstream approaches.

A protocol for the intercomparison of marine fishery and ecosystem models: Fish-MIP v1.0

NASA Astrophysics Data System (ADS)

Tittensor, Derek P.; Eddy, Tyler D.; Lotze, Heike K.; Galbraith, Eric D.; Cheung, William; Barange, Manuel; Blanchard, Julia L.; Bopp, Laurent; Bryndum-Buchholz, Andrea; Büchner, Matthias; Bulman, Catherine; Carozza, David A.; Christensen, Villy; Coll, Marta; Dunne, John P.; Fernandes, Jose A.; Fulton, Elizabeth A.; Hobday, Alistair J.; Huber, Veronika; Jennings, Simon; Jones, Miranda; Lehodey, Patrick; Link, Jason S.; Mackinson, Steve; Maury, Olivier; Niiranen, Susa; Oliveros-Ramos, Ricardo; Roy, Tilla; Schewe, Jacob; Shin, Yunne-Jai; Silva, Tiago; Stock, Charles A.; Steenbeek, Jeroen; Underwood, Philip J.; Volkholz, Jan; Watson, James R.; Walker, Nicola D.

2018-04-01

Model intercomparison studies in the climate and Earth sciences communities have been crucial to building credibility and coherence for future projections. They have quantified variability among models, spurred model development, contrasted within- and among-model uncertainty, assessed model fits to historical data, and provided ensemble projections of future change under specified scenarios. Given the speed and magnitude of anthropogenic change in the marine environment and the consequent effects on food security, biodiversity, marine industries, and society, the time is ripe for similar comparisons among models of fisheries and marine ecosystems. Here, we describe the Fisheries and Marine Ecosystem Model Intercomparison Project protocol version 1.0 (Fish-MIP v1.0), part of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), which is a cross-sectoral network of climate impact modellers. Given the complexity of the marine ecosystem, this class of models has substantial heterogeneity of purpose, scope, theoretical underpinning, processes considered, parameterizations, resolution (grain size), and spatial extent. This heterogeneity reflects the lack of a unified understanding of the marine ecosystem and implies that the assemblage of all models is more likely to include a greater number of relevant processes than any single model. The current Fish-MIP protocol is designed to allow these heterogeneous models to be forced with common Earth System Model (ESM) Coupled Model Intercomparison Project Phase 5 (CMIP5) outputs under prescribed scenarios for historic (from the 1950s) and future (to 2100) time periods; it will be adapted to CMIP phase 6 (CMIP6) in future iterations. It also describes a standardized set of outputs for each participating Fish-MIP model to produce. This enables the broad characterization of differences between and uncertainties within models and projections when assessing climate and fisheries impacts on marine ecosystems and the services they provide. The systematic generation, collation, and comparison of results from Fish-MIP will inform an understanding of the range of plausible changes in marine ecosystems and improve our capacity to define and convey the strengths and weaknesses of model-based advice on future states of marine ecosystems and fisheries. Ultimately, Fish-MIP represents a step towards bringing together the marine ecosystem modelling community to produce consistent ensemble medium- and long-term projections of marine ecosystems.

The sensitivity of the Arctic sea ice to orbitally induced insolation changes: a study of the mid-Holocene Paleoclimate Modelling Intercomparison Project 2 and 3 simulations

NASA Astrophysics Data System (ADS)

Berger, M.; Brandefelt, J.; Nilsson, J.

2013-04-01

In the present work the Arctic sea ice in the mid-Holocene and the pre-industrial climates are analysed and compared on the basis of climate-model results from the Paleoclimate Modelling Intercomparison Project phase 2 (PMIP2) and phase 3 (PMIP3). The PMIP3 models generally simulate smaller and thinner sea-ice extents than the PMIP2 models both for the pre-industrial and the mid-Holocene climate. Further, the PMIP2 and PMIP3 models all simulate a smaller and thinner Arctic summer sea-ice cover in the mid-Holocene than in the pre-industrial control climate. The PMIP3 models also simulate thinner winter sea ice than the PMIP2 models. The winter sea-ice extent response, i.e. the difference between the mid-Holocene and the pre-industrial climate, varies among both PMIP2 and PMIP3 models. Approximately one half of the models simulate a decrease in winter sea-ice extent and one half simulates an increase. The model-mean summer sea-ice extent is 11 % (21 %) smaller in the mid-Holocene than in the pre-industrial climate simulations in the PMIP2 (PMIP3). In accordance with the simple model of Thorndike (1992), the sea-ice thickness response to the insolation change from the pre-industrial to the mid-Holocene is stronger in models with thicker ice in the pre-industrial climate simulation. Further, the analyses show that climate models for which the Arctic sea-ice responses to increasing atmospheric CO2 concentrations are similar may simulate rather different sea-ice responses to the change in solar forcing between the mid-Holocene and the pre-industrial. For two specific models, which are analysed in detail, this difference is found to be associated with differences in the simulated cloud fractions in the summer Arctic; in the model with a larger cloud fraction the effect of insolation change is muted. A sub-set of the mid-Holocene simulations in the PMIP ensemble exhibit open water off the north-eastern coast of Greenland in summer, which can provide a fetch for surface waves. This is in broad agreement with recent analyses of sea-ice proxies, indicating that beach-ridges formed on the north-eastern coast of Greenland during the early- to mid-Holocene.

A multimodel intercomparison of resolution effects on precipitation: simulations and theory

DOE PAGES

Rauscher, Sara A.; O?Brien, Travis A.; Piani, Claudio; ...

2016-02-27

An ensemble of six pairs of RCM experiments performed at 25 and 50 km for the period 1961–2000 over a large European domain is examined in order to evaluate the effects of resolution on the simulation of daily precipitation statistics. Application of the non-parametric two-sample Kolmorgorov–Smirnov test, which tests for differences in the location and shape of the probability distributions of two samples, shows that the distribution of daily precipitation differs between the pairs of simulations over most land areas in both summer and winter, with the strongest signal over southern Europe. Two-dimensional histograms reveal that precipitation intensity increases with resolutionmore » over almost the entire domain in both winter and summer. In addition, the 25 km simulations have more dry days than the 50 km simulations. The increase in dry days with resolution is indicative of an improvement in model performance at higher resolution, while the more intense precipitation exceeds observed values. The systematic increase in precipitation extremes with resolution across all models suggests that this response is fundamental to model formulation. Simple theoretical arguments suggest that fluid continuity, combined with the emergent scaling properties of the horizontal wind field, results in an increase in resolved vertical transport as grid spacing decreases. This increase in resolution-dependent vertical mass flux then drives an intensification of convergence and resolvable-scale precipitation as grid spacing decreases. In conclusion, this theoretical result could help explain the increasingly, and often anomalously, large stratiform contribution to total rainfall observed with increasing resolution in many regional and global models.« less

A multimodel intercomparison of resolution effects on precipitation: simulations and theory

NASA Astrophysics Data System (ADS)

Rauscher, Sara A.; O'Brien, Travis A.; Piani, Claudio; Coppola, Erika; Giorgi, Filippo; Collins, William D.; Lawston, Patricia M.

2016-10-01

An ensemble of six pairs of RCM experiments performed at 25 and 50 km for the period 1961-2000 over a large European domain is examined in order to evaluate the effects of resolution on the simulation of daily precipitation statistics. Application of the non-parametric two-sample Kolmorgorov-Smirnov test, which tests for differences in the location and shape of the probability distributions of two samples, shows that the distribution of daily precipitation differs between the pairs of simulations over most land areas in both summer and winter, with the strongest signal over southern Europe. Two-dimensional histograms reveal that precipitation intensity increases with resolution over almost the entire domain in both winter and summer. In addition, the 25 km simulations have more dry days than the 50 km simulations. The increase in dry days with resolution is indicative of an improvement in model performance at higher resolution, while the more intense precipitation exceeds observed values. The systematic increase in precipitation extremes with resolution across all models suggests that this response is fundamental to model formulation. Simple theoretical arguments suggest that fluid continuity, combined with the emergent scaling properties of the horizontal wind field, results in an increase in resolved vertical transport as grid spacing decreases. This increase in resolution-dependent vertical mass flux then drives an intensification of convergence and resolvable-scale precipitation as grid spacing decreases. This theoretical result could help explain the increasingly, and often anomalously, large stratiform contribution to total rainfall observed with increasing resolution in many regional and global models.

Report on the emergency response to the event on May 14, 1997, at the plutonuim reclamation facility, Hanford Site, Richland,Washington

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shoop, D.S.

1997-08-20

On the evening of May 14,1997, a chemical explosion Occurred at the Plutonium Reclamation Facility (PRF) in the 200 West Area(200-W) of the Hanford Site. The event warranted the declaration of an Alert emergency, activation of the Hanford Emergency Response Organization (BRO), and notification of offsite agencies. As a result of the emergency declaration, a subsequent evaluation was conducted to assess: 9 the performance of the emergency response organization o the occupational health response related to emergency activities o event notifications to offsite and environmental agencies. Additionally, the evaluation was designed to: 9 document the chronology of emergency and occupationalmore » health responses and environmental notifications connected with the explosion at the facility 0 assess the adequacy of the Hanford Site emergency preparedness activities; response readiness; and emergency management actions, occupational health, and environmental actions 0 provide an analysis of the causes of the deficiencies and weaknesses in the preparedness and response system that have been identified in the evaluation of the response a assign organizational responsibility to correct deficiencies and weaknesses a improve future performance 0 adjust elements of emergency implementing procedures and emergency preparedness activities.« less

The English Channel: Contamination status of its transitional and coastal waters.

PubMed

Tappin, A D; Millward, G E

2015-06-30

The chemical contamination (organic compounds, metals, radionuclides, microplastics, nutrients) of English Channel waters has been reviewed, focussing on the sources, concentrations and impacts. River loads were only reliable for Pb, whereas atmospheric loads appeared robust for Cd, Pb, Hg, PCB-153 and γ-HCH. Temporal trends in atmospheric inputs were decreasing. Contaminant concentrations in biota were relatively constant or decreasing, but not for Cd, Hg and HBCDD, and deleterious impacts on fish and copepods were reported. However, data on ecotoxicological effects were generally sparse for legacy and emerging contaminants. Intercomparison of activity concentrations of artificial radionuclides in sediments and biota on both Channel coasts was hindered by differences in methodological approaches. Riverine phosphate loads decreased with time, while nitrate loads remained uniform. Increased biomass of algae, attributable to terrestrial inputs of nutrients, has affected benthic production and shellfisheries. A strategic approach to the identification of contaminant impacts on marine biota is recommended. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hyperspectral remote sensing of plant pigments.

PubMed

Blackburn, George Alan

2007-01-01

The dynamics of pigment concentrations are diagnostic of a range of plant physiological properties and processes. This paper appraises the developing technologies and analytical methods for quantifying pigments non-destructively and repeatedly across a range of spatial scales using hyperspectral remote sensing. Progress in deriving predictive relationships between various characteristics and transforms of hyperspectral reflectance data are evaluated and the roles of leaf and canopy radiative transfer models are reviewed. Requirements are identified for more extensive intercomparisons of different approaches and for further work on the strategies for interpreting canopy scale data. The paper examines the prospects for extending research to the wider range of pigments in addition to chlorophyll, testing emerging methods of hyperspectral analysis and exploring the fusion of hyperspectral and LIDAR remote sensing. In spite of these opportunities for further development and the refinement of techniques, current evidence of an expanding range of applications in the ecophysiological, environmental, agricultural, and forestry sciences highlights the growing value of hyperspectral remote sensing of plant pigments.

Multibiodose radiation emergency triage categorization software.

PubMed

Ainsbury, Elizabeth A; Barnard, Stephen; Barrios, Lleonard; Fattibene, Paola; de Gelder, Virginie; Gregoire, Eric; Lindholm, Carita; Lloyd, David; Nergaard, Inger; Rothkamm, Kai; Romm, Horst; Scherthan, Harry; Thierens, Hubert; Vandevoorde, Charlot; Woda, Clemens; Wojcik, Andrzej

2014-07-01

In this note, the authors describe the MULTIBIODOSE software, which has been created as part of the MULTIBIODOSE project. The software enables doses estimated by networks of laboratories, using up to five retrospective (biological and physical) assays, to be combined to give a single estimate of triage category for each individual potentially exposed to ionizing radiation in a large scale radiation accident or incident. The MULTIBIODOSE software has been created in Java. The usage of the software is based on the MULTIBIODOSE Guidance: the program creates a link to a single SQLite database for each incident, and the database is administered by the lead laboratory. The software has been tested with Java runtime environment 6 and 7 on a number of different Windows, Mac, and Linux systems, using data from a recent intercomparison exercise. The Java program MULTIBIODOSE_1.0.jar is freely available to download from http://www.multibiodose.eu/software or by contacting the software administrator: MULTIBIODOSE-software@gmx.com.

44 CFR 352.27 - Federal role in the emergency response.

Code of Federal Regulations, 2014 CFR

2014-10-01

... response. 352.27 Section 352.27 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... Federal Participation § 352.27 Federal role in the emergency response. In addition to the Federal component of the licensee offsite emergency response plan described in subpart B (§ 352.26), and after...

44 CFR 352.27 - Federal role in the emergency response.

Code of Federal Regulations, 2011 CFR

2011-10-01

... response. 352.27 Section 352.27 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... Federal Participation § 352.27 Federal role in the emergency response. In addition to the Federal component of the licensee offsite emergency response plan described in subpart B (§ 352.26), and after...

44 CFR 352.27 - Federal role in the emergency response.

Code of Federal Regulations, 2013 CFR

2013-10-01

... response. 352.27 Section 352.27 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... Federal Participation § 352.27 Federal role in the emergency response. In addition to the Federal component of the licensee offsite emergency response plan described in subpart B (§ 352.26), and after...

44 CFR 352.27 - Federal role in the emergency response.

Code of Federal Regulations, 2012 CFR

2012-10-01

... response. 352.27 Section 352.27 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY... Federal Participation § 352.27 Federal role in the emergency response. In addition to the Federal component of the licensee offsite emergency response plan described in subpart B (§ 352.26), and after...

The Soil Model Development and Intercomparison Panel (SoilMIP) of the International Soil Modeling Consortium (ISMC)

NASA Astrophysics Data System (ADS)

Vanderborght, Jan; Priesack, Eckart

2017-04-01

The Soil Model Development and Intercomparison Panel (SoilMIP) is an initiative of the International Soil Modeling Consortium. Its mission is to foster the further development of soil models that can predict soil functions and their changes (i) due to soil use and land management and (ii) due to external impacts of climate change and pollution. Since soil functions and soil threats are diverse but linked with each other, the overall aim is to develop holistic models that represent the key functions of the soil system and the links between them. These models should be scaled up and integrated in terrestrial system models that describe the feedbacks between processes in the soil and the other terrestrial compartments. We propose and illustrate a few steps that could be taken to achieve these goals. A first step is the development of scenarios that compare simulations by models that predict the same or different soil services. Scenarios can be considered at three different levels of comparisons: scenarios that compare the numerics (accuracy but also speed) of models, scenarios that compare the effect of differences in process descriptions, and scenarios that compare simulations with experimental data. A second step involves the derivation of metrics or summary statistics that effectively compare model simulations and disentangle parameterization from model concept differences. These metrics can be used to evaluate how more complex model simulations can be represented by simpler models using an appropriate parameterization. A third step relates to the parameterization of models. Application of simulation models implies that appropriate model parameters have to be defined for a range of environmental conditions and locations. Spatial modelling approaches are used to derive parameter distributions. Considering that soils and their properties emerge from the interaction between physical, chemical and biological processes, the combination of spatial models with process models would lead to consistent parameter distributions correlations and could potentially represent self-organizing processes in soils and landscapes.

The SPARC Intercomparison of Middle Atmosphere Climatologies

NASA Technical Reports Server (NTRS)

Randel, William; Fleming, Eric; Geller, Marvin; Gelman, Mel; Hamilton, Kevin; Karoly, David; Ortland, Dave; Pawson, Steve; Swinbank, Richard; Udelhofen, Petra

2003-01-01

Our current confidence in 'observed' climatological winds and temperatures in the middle atmosphere (over altitudes approx. 10-80 km) is assessed by detailed intercomparisons of contemporary and historic data sets. These data sets include global meteorological analyses and assimilations, climatologies derived from research satellite measurements, and historical reference atmosphere circulation statistics. We also include comparisons with historical rocketsonde wind and temperature data, and with more recent lidar temperature measurements. The comparisons focus on a few basic circulation statistics, such as temperature, zonal wind, and eddy flux statistics. Special attention is focused on tropical winds and temperatures, where large differences exist among separate analyses. Assimilated data sets provide the most realistic tropical variability, but substantial differences exist among current schemes.

LIDAR mapping of ozone-episode dynamics in Paris and intercomparison with spot analyzers Supplementary material available at http://link.springer.de/journals/apb

NASA Astrophysics Data System (ADS)

Thomasson, A.; Geffroy, S.; Frejafon, E.; Weidauer, D.; Fabian, R.; Godet, Y.; Nominé, M.; Ménard, T.; Rairoux, P.; Moeller, D.; Wolf, J. P.

Continuous mapping of an ozone episode in Paris in June 1999 has been performed using a differential absorption lidar system. The 2D ozone concentration vertical maps recorded over 33 h at the Champ de Mars are compiled in a video clip that gives access to local photochemical dynamics with unprecedented precision. The lidar data are compared over the whole period with point monitors located at 0-, 50-, and 300-m altitudes on the Eiffel Tower. Very good agreement is found when spatial resolution, acquisition time, and required concentration accuracy are optimized. Sensitivity to these parameters for successful intercomparison in urban areas is discussed.

An intercomparison of longwave measurements by ERBE radiometers on the NOAA-9 and ERBS satellites

NASA Technical Reports Server (NTRS)

House, Frederick B.

1989-01-01

Two instrument modules of each satellite on which the Earth Radiation Budget Experiment (ERBE) is orbiting observe components of the earth radiation budget with three different scales of earth view. An intercomparison of longwave measurements by these instruments provides relative information concerning radiometric performance at satellite altitude, techniques of estimating upwelling exitances, and an end-to-end evaluation of the data processing system. Results indicate that the ERBE radiometers are mildly sensitive to varying thermal loads from the spacecraft and/or the earth-space environment. Radiometric variations at the satellite and methods of data interpretation contribute about equally to the uncertainty of radiant exitances from the earth.

Intercomparisons of radiosondes and an airborne refractometer for measuring radio ducts

NASA Astrophysics Data System (ADS)

Morrissey, J. F.; Izumi, Y.; Cote, O. R.

1986-07-01

The capabilities of two types of radiosondes and an aircraft refractometer to measure radio ducting conditions were compared in a series of flights in September 1985 at Chatham, Mass., on Cape Cod. The tests were part of a program studying radio propagation on Air Force communication links. The intercomparisons were made between data from a refractometer mounted on a small single engine aircraft (Cessna 172) and data from an operational National Weather Service synoptic sounding system. The synoptic sonde and the portable sonde were often on the same balloon train. The comparisons show that the aircraft refractometer data indicate the highest number of ducts and the synoptic data the least number of ducts.

Intercomparison of analytical methods for arsenic speciation in human urine.

PubMed

Crecelius, E; Yager, J

1997-06-01

An intercomparison exercise was conducted for the quantification of arsenic species in spiked human urine. The primary objective of the exercise was to determine the variance among laboratories in the analysis of arsenic species such as inorganic As (As+3 and As+5), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA). Laboratories that participated had previous experience with arsenic speciation analysis. The results of this interlaboratory comparison are encouraging. There is relatively good agreement on the concentrations of these arsenic species in urine at concentrations that are relevant to research on the metabolism of arsenic in humans and other mammals. Both the accuracy and precision are relatively poor for arsenic concentrations of less than about 5 micrograms/l.

An evaluation of 20th century climate for the Southeastern United States as simulated by Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models

USGS Publications Warehouse

David E. Rupp,

2016-05-05

The 20th century climate for the Southeastern United States and surrounding areas as simulated by global climate models used in the Coupled Model Intercomparison Project Phase 5 (CMIP5) was evaluated. A suite of statistics that characterize various aspects of the regional climate was calculated from both model simulations and observation-based datasets. CMIP5 global climate models were ranked by their ability to reproduce the observed climate. Differences in the performance of the models between regions of the United States (the Southeastern and Northwestern United States) warrant a regional-scale assessment of CMIP5 models.

40 CFR 1.47 - Office of Solid Waste and Emergency Response.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the Agency's solid and hazardous wastes and emergency response programs. This Office has primary..., under the supervision of a Director, is responsible for the emergency and remedial response functions of...) Providing direction, guidance, and support to the Agency's non-enforcement emergency and remedial response...

The PMIP4 contribution to CMIP6 - Part 1: Overview and over-arching analysis plan

NASA Astrophysics Data System (ADS)

Kageyama, Masa; Braconnot, Pascale; Harrison, Sandy P.; Haywood, Alan M.; Jungclaus, Johann H.; Otto-Bliesner, Bette L.; Peterschmitt, Jean-Yves; Abe-Ouchi, Ayako; Albani, Samuel; Bartlein, Patrick J.; Brierley, Chris; Crucifix, Michel; Dolan, Aisling; Fernandez-Donado, Laura; Fischer, Hubertus; Hopcroft, Peter O.; Ivanovic, Ruza F.; Lambert, Fabrice; Lunt, Daniel J.; Mahowald, Natalie M.; Peltier, W. Richard; Phipps, Steven J.; Roche, Didier M.; Schmidt, Gavin A.; Tarasov, Lev; Valdes, Paul J.; Zhang, Qiong; Zhou, Tianjun

2018-03-01

This paper is the first of a series of four GMD papers on the PMIP4-CMIP6 experiments. Part 2 (Otto-Bliesner et al., 2017) gives details about the two PMIP4-CMIP6 interglacial experiments, Part 3 (Jungclaus et al., 2017) about the last millennium experiment, and Part 4 (Kageyama et al., 2017) about the Last Glacial Maximum experiment. The mid-Pliocene Warm Period experiment is part of the Pliocene Model Intercomparison Project (PlioMIP) - Phase 2, detailed in Haywood et al. (2016).The goal of the Paleoclimate Modelling Intercomparison Project (PMIP) is to understand the response of the climate system to different climate forcings for documented climatic states very different from the present and historical climates. Through comparison with observations of the environmental impact of these climate changes, or with climate reconstructions based on physical, chemical, or biological records, PMIP also addresses the issue of how well state-of-the-art numerical models simulate climate change. Climate models are usually developed using the present and historical climates as references, but climate projections show that future climates will lie well outside these conditions. Palaeoclimates very different from these reference states therefore provide stringent tests for state-of-the-art models and a way to assess whether their sensitivity to forcings is compatible with palaeoclimatic evidence. Simulations of five different periods have been designed to address the objectives of the sixth phase of the Coupled Model Intercomparison Project (CMIP6): the millennium prior to the industrial epoch (CMIP6 name: past1000); the mid-Holocene, 6000 years ago (midHolocene); the Last Glacial Maximum, 21 000 years ago (lgm); the Last Interglacial, 127 000 years ago (lig127k); and the mid-Pliocene Warm Period, 3.2 million years ago (midPliocene-eoi400). These climatic periods are well documented by palaeoclimatic and palaeoenvironmental records, with climate and environmental changes relevant for the study and projection of future climate changes. This paper describes the motivation for the choice of these periods and the design of the numerical experiments and database requests, with a focus on their novel features compared to the experiments performed in previous phases of PMIP and CMIP. It also outlines the analysis plan that takes advantage of the comparisons of the results across periods and across CMIP6 in collaboration with other MIPs.

Can a reduction of solar irradiance counteract CO2-induced climate change? - Results from four Earth system models

NASA Astrophysics Data System (ADS)

Schmidt, H.; Alterskjær, K.; Karam, D. Bou; Boucher, O.; Jones, A.; Kristjansson, J. E.; Niemeier, U.; Schulz, M.; Aaheim, A.; Benduhn, F.; Lawrence, M.; Timmreck, C.

2012-01-01

In this study we compare the response of four state-of-the-art Earth system models to climate engineering under scenario G1 of the GeoMIP and IMPLICC model intercomparison projects. In G1, the radiative forcing from an instantaneous quadrupling of the CO2 concentration, starting from the preindustrial level, is balanced by a reduction of the solar constant. Model responses to the two counteracting forcings in G1 are compared to the preindustrial climate in terms of global means and regional patterns and their robustness. While the global mean surface air temperature in G1 remains almost unchanged, the meridional temperature gradient is reduced in all models compared to the control simulation. Another robust response is the global reduction of precipitation with strong effects in particular over North and South America and northern Eurasia. It is shown that this reduction is only partly compensated by a reduction in evaporation so that large continental regions are drier in the engineered climate. In comparison to the climate response to a quadrupling of CO2 alone the temperature responses are small in experiment G1. Precipitation responses are, however, of comparable magnitude but in many regions of opposite sign.

40 CFR 68.180 - Emergency response program.

Code of Federal Regulations, 2011 CFR

2011-07-01

... activities and the emergency response plan is coordinated. (c) The owner or operator shall list other Federal... (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.180 Emergency response program... written emergency response plan? (2) Does the plan include specific actions to be taken in response to an...

40 CFR 68.180 - Emergency response program.

Code of Federal Regulations, 2013 CFR

2013-07-01

... activities and the emergency response plan is coordinated. (c) The owner or operator shall list other Federal... (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.180 Emergency response program... written emergency response plan? (2) Does the plan include specific actions to be taken in response to an...

40 CFR 68.180 - Emergency response program.

Code of Federal Regulations, 2012 CFR

2012-07-01

... activities and the emergency response plan is coordinated. (c) The owner or operator shall list other Federal... (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.180 Emergency response program... written emergency response plan? (2) Does the plan include specific actions to be taken in response to an...

40 CFR 68.180 - Emergency response program.

Code of Federal Regulations, 2014 CFR

2014-07-01

... activities and the emergency response plan is coordinated. (c) The owner or operator shall list other Federal... (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.180 Emergency response program... written emergency response plan? (2) Does the plan include specific actions to be taken in response to an...

RMP Guidance for Chemical Distributors - Chapter 8: Emergency Response Program

EPA Pesticide Factsheets

Depending on the level of processes at your facility, part 68 may require an emergency response program: an emergency response plan, emergency response equipment procedures, employee training, and procedures to ensure the program is up-to-date.

SIMBIOS Project 1999 Annual Report

NASA Technical Reports Server (NTRS)

McClain, Charles R.; Fargion, Giulietta S.

1999-01-01

The purpose of this technical memorandum is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities, NASA Research Announcement (NRA) research status, satellite data processing, data product validation, and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project.

Throughfall Displacement Experiment (TDE) Ecosystem Model Intercomparison Project Data Archive

DOE Data Explorer

Hanson, Paul J. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Amthor, Jeffrey S. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Baldocchi, Dennis D. [University of California, Berkeley; Grant, Robert F. [University of Alberta, Canada; Hartley, Anne E. [Ohio State University; Hui, Dafeng [University of Oklahoma; Hunt, Jr., E. Raymond [Agricultural Research Service, U.S. Department of Agriculture; Johnson, Dale W. [University of Nevada, Reno; Kimball, John S. [University of Montana; King, Anthony W. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA); Luo, Yiqi [University of Oklahoma; McNulty, Steven G. [Southern Global Change Program, U.S. Forest Service, U.S. Department of Agriculture; Sun, Ge [North Carolina State University, Raleigh, NC (USA); Thornton, Peter E. [University of Montana; Wang, Shusen [Geomatics Canada - Canada Centre for Remote Sensing Natural Resources, Canada; Williams, Matthew [University of Edinburgh, United Kingdom; Wilson, Kell B. [National Oceanic and Atmospheric Administration, U.S. Department of Commerce; Wullschleger, Stanley D. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA)

2002-08-01

This archive provides and documents data from a project whose purpose is to compare the output of various ecosystem models when they are run with the data from the Throughfall Displacement Experiment (TDE) at Walker Branch Watershed, Oak Ridge, Tennessee. The project is not designed to determine which models are "best" for diagnosis (i.e., explaining the current functioning of the system) or prognosis (i.e., predicting the response of the system to future conditions), but, rather, to clarify similarities and differences among the models and their components, so that all models can be improved. Data archive: ftp://cdiac.ornl.gov/ftp/tdemodel/. TDE data archive web site: http://cdiac.ess-dive.lbl.gov/epubs/ndp/ndp078a/ndp078a.html.

SIMBIOS Project 1998 Annual Report

NASA Technical Reports Server (NTRS)

McClain, Charles R.; Fargion, Giulietta, S.

1999-01-01

The purpose of this series of technical reports is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Ocean Studies (SIMBIOS) Project activities, NASA Research Announcement (NRA) research status, satellite data processing, data product validation and field calibration. This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant to substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issues by an operational project.

Using principles from emergency management to improve emergency response plans for research animals.

PubMed

Vogelweid, Catherine M

2013-10-01

Animal research regulatory agencies have issued updated requirements for emergency response planning by regulated research institutions. A thorough emergency response plan is an essential component of an institution's animal care and use program, but developing an effective plan can be a daunting task. The author provides basic information drawn from the field of emergency management about best practices for developing emergency response plans. Planners should use the basic principles of emergency management to develop a common-sense approach to managing emergencies in their facilities.

A large-scale intercomparison of stratospheric vertical distributions of NO2 and BrO retrieved from the SCIAMACHY limb measurements and ground-based twilight observations

NASA Astrophysics Data System (ADS)

Rozanov, Alexei; Hendrick, Francois; Lotz, Wolfhardt; van Roozendael, Michel; Bovensmann, Heinrich; Burrows, John P.

This study is devoted to the intercomparison of NO2 and BrO vertical profiles obtained from the satellite and ground-based measurements. Although, the ground-based observations are performed only at selected locations, they have a great potential to be used for the validation of satellite measurements since continuous long-term measurement series performed with the same instruments are available. Thus, long-term trends in the observed species can be analyzed and intercompared. Previous intercomparisons of the vertical distributions of NO2 and BrO retrieved from SCIAMACHY limb measurements at the University of Bremen and obtained at IASB-BIRA by applying a profiling technique to ground-based zenith-sky DOAS observations have shown a good agreement between the results of completely different measurement techniques. However, only a relatively short time period of one year was analyzed so far which do not allow investigating seasonal variations and trends. Furthermore, some minor discrepancies are still to be analyzed. In the current study, several years datasets obtained at Observatoire de Haute-Provence (OHP) in France and in Harestua in Norway will be compared to the retrievals of SCIAMACHY limb measurements. Seasonal and annual variations will be analyzed and possible reasons for the remaining discrepancies will be discussed.

Constraints and potentials of future irrigation water availability on agricultural production under climate change

PubMed Central

Elliott, Joshua; Deryng, Delphine; Müller, Christoph; Frieler, Katja; Konzmann, Markus; Gerten, Dieter; Glotter, Michael; Flörke, Martina; Wada, Yoshihide; Best, Neil; Eisner, Stephanie; Fekete, Balázs M.; Folberth, Christian; Foster, Ian; Gosling, Simon N.; Haddeland, Ingjerd; Khabarov, Nikolay; Ludwig, Fulco; Masaki, Yoshimitsu; Olin, Stefan; Rosenzweig, Cynthia; Ruane, Alex C.; Satoh, Yusuke; Schmid, Erwin; Stacke, Tobias; Tang, Qiuhong; Wisser, Dominik

2014-01-01

We compare ensembles of water supply and demand projections from 10 global hydrological models and six global gridded crop models. These are produced as part of the Inter-Sectoral Impacts Model Intercomparison Project, with coordination from the Agricultural Model Intercomparison and Improvement Project, and driven by outputs of general circulation models run under representative concentration pathway 8.5 as part of the Fifth Coupled Model Intercomparison Project. Models project that direct climate impacts to maize, soybean, wheat, and rice involve losses of 400–1,400 Pcal (8–24% of present-day total) when CO2 fertilization effects are accounted for or 1,400–2,600 Pcal (24–43%) otherwise. Freshwater limitations in some irrigated regions (western United States; China; and West, South, and Central Asia) could necessitate the reversion of 20–60 Mha of cropland from irrigated to rainfed management by end-of-century, and a further loss of 600–2,900 Pcal of food production. In other regions (northern/eastern United States, parts of South America, much of Europe, and South East Asia) surplus water supply could in principle support a net increase in irrigation, although substantial investments in irrigation infrastructure would be required. PMID:24344283

IPRT polarized radiative transfer model intercomparison project - Phase A

NASA Astrophysics Data System (ADS)

Emde, Claudia; Barlakas, Vasileios; Cornet, Céline; Evans, Frank; Korkin, Sergey; Ota, Yoshifumi; Labonnote, Laurent C.; Lyapustin, Alexei; Macke, Andreas; Mayer, Bernhard; Wendisch, Manfred

2015-10-01

The polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. For this reason an increasing number of polarimetric observations are performed from space, from the ground and from aircraft. Polarized radiative transfer models are required to interpret and analyse these measurements and to develop retrieval algorithms exploiting polarimetric observations. In the last years a large number of new codes have been developed, mostly for specific applications. Benchmark results are available for specific cases, but not for more sophisticated scenarios including polarized surface reflection and multi-layer atmospheres. The International Polarized Radiative Transfer (IPRT) working group of the International Radiation Commission (IRC) has initiated a model intercomparison project in order to fill this gap. This paper presents the results of the first phase A of the IPRT project which includes ten test cases, from simple setups with only one layer and Rayleigh scattering to rather sophisticated setups with a cloud embedded in a standard atmosphere above an ocean surface. All scenarios in the first phase A of the intercomparison project are for a one-dimensional plane-parallel model geometry. The commonly established benchmark results are available at the IPRT website.

LLNL Results from CALIBAN-PROSPERO Nuclear Accident Dosimetry Experiments in September 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lobaugh, M. L.; Hickman, D. P.; Wong, C. W.

2015-05-21

Lawrence Livermore National Laboratory (LLNL) uses thin neutron activation foils, sulfur, and threshold energy shielding to determine neutron component doses and the total dose from neutrons in the event of a nuclear criticality accident. The dosimeter also uses a DOELAP accredited Panasonic UD-810 (Panasonic Industrial Devices Sales Company of America, 2 Riverfront Plaza, Newark, NJ 07102, U.S.A.) thermoluminescent dosimetery system (TLD) for determining the gamma component of the total dose. LLNL has participated in three international intercomparisons of nuclear accident dosimeters. In October 2009, LLNL participated in an exercise at the French Commissariat à l’énergie atomique et aux énergies alternativesmore » (Alternative Energies and Atomic Energy Commission- CEA) Research Center at Valduc utilizing the SILENE reactor (Hickman, et.al. 2010). In September 2010, LLNL participated in a second intercomparison at CEA Valduc, this time with exposures at the CALIBAN reactor (Hickman et al. 2011). This paper discusses LLNL’s results of a third intercomparison hosted by the French Institut de Radioprotection et de Sûreté Nucléaire (Institute for Radiation Protection and Nuclear Safety- IRSN) with exposures at two CEA Valduc reactors (CALIBAN and PROSPERO) in September 2014. Comparison results between the three participating facilities is presented elsewhere (Chevallier 2015; Duluc 2015).« less

An intercomparison of instrumentation for tropospheric measurements of dimethyl sulfide: Aircraft results for concentrations at the parts-per-trillion level

NASA Technical Reports Server (NTRS)

Gregory, Gerald L.; Warren, Linda S.; Davis, Douglas D.; Andreae, Meinrat O.; Bandy, Alan R.; Ferek, Ronald J.; Johnson, James E.; Saltzman, Eric S.; Cooper, David J.

1993-01-01

This paper reports results from NASA's Chemical Instrumentation and Test Evaluation (CITE 3) during which airborne measurements of dimethyl sulfide (DMS) from six instruments were intercompared. Represented by the six instruments are three fundamentally different detection principles (flame photometric, mass spectrometric, and electron capture after fluorination); three collection/preconcentration methods (cryogenic, gold wool absorption, and polymer absorbent); and three types of oxidant scrubbers (solid phase alkaline, aqueous reactor, and cotton). The measurements were made over the Atlantic Ocean in August/September 1989 during flights from NASA's Wallops Flight Center, Virginia, and Natal, Brazil. The majority of the intercomparisons are at DMS mixing ratios less than 50 pptv. Results show that instrument agreement is of the order of a few pptv for mixing ratios less than 50 pptv and to within about 15% above 50 pptv. Statistically significant (95% confidence) measurement biases were noted among some of the techniques. However, in all cases, any bias is small and within the accuracy of the measurements and prepared DMS standards. Thus, we conclude that the techniques intercompared during CITE 3 provide equally valid measurements of DMS in the range of a few pptv to 100 pptv (upper range of the intercomparisons).

Large-Scale Features of Pliocene Climate: Results from the Pliocene Model Intercomparison Project

NASA Technical Reports Server (NTRS)

Haywood, A. M.; Hill, D.J.; Dolan, A. M.; Otto-Bliesner, B. L.; Bragg, F.; Chan, W.-L.; Chandler, M. A.; Contoux, C.; Dowsett, H. J.; Jost, A.;

Future vegetation ecosystem response to warming climate over the Tibetan Plateau

NASA Astrophysics Data System (ADS)

Bao, Y.; Gao, Y.; Wang, Y.

2017-12-01

The amplified vegetation response to climate variability has been found over the Tibetan Plateau (TP) in recent decades. In this study, the potential impacts of 21st century climate change on the vegetation ecosystem over the TP are assessed based on the dynamic vegetation outputs of models from Coupled Model Intercomparison Project Phase 5 (CMIP5), and the sensitivity of the TP vegetation in response to warming climate was investigated. Models project a continuous and accelerating greening in future, especially in the eastern TP, which closely associates with the plant type upgrade due to the pronouncing warming in growing season.Vegetation leaf area index (LAI) increase well follows the global warming, suggesting the warming climate instead of co2 fertilization controlls the future TP plant growth. The warming spring may advance the start of green-up day and extend the growing season length. More carbon accumulation in vegetation and soil will intensify the TP carbon cycle and will keep it as a carbon sink in future. Keywords: Leaf Area Index (LAI), Climate Change, Global Dynamic Vegetation Models (DGVMs), CMIP5, Tibetan Plateau (TP)

How consistent are precipitation patterns predicted by GCMs in the absence of cloud radiative effects?

NASA Astrophysics Data System (ADS)

Popke, Dagmar; Bony, Sandrine; Mauritsen, Thorsten; Stevens, Bjorn

2015-04-01

Model simulations with state-of-the-art general circulation models reveal a strong disagreement concerning the simulated regional precipitation patterns and their changes with warming. The deviating precipitation response even persists when reducing the model experiment complexity to aquaplanet simulation with forced sea surface temperatures (Stevens and Bony, 2013). To assess feedbacks between clouds and radiation on precipitation responses we analyze data from 5 models performing the aquaplanet simulations of the Clouds On Off Klima Intercomparison Experiment (COOKIE), where the interaction of clouds and radiation is inhibited. Although cloud radiative effects are then disabled, the precipitation patterns among models are as diverse as with cloud radiative effects switched on. Disentangling differing model responses in such simplified experiments thus appears to be key to better understanding the simulated regional precipitation in more standard configurations. By analyzing the local moisture and moist static energy budgets in the COOKIE experiments we investigate likely causes for the disagreement among models. References Stevens, B. & S. Bony: What Are Climate Models Missing?, Science, 2013, 340, 1053-1054

ENSO Transition Asymmetry: Internal and External Causes and Intermodel Diversity

NASA Astrophysics Data System (ADS)

An, Soon-Il; Kim, Ji-Won

2018-05-01

El Niño is frequently followed by La Niña, but the opposite case rarely happens. Here we explore a mechanism for such an asymmetrical transition and its future changes. Internally, the asymmetrical response of upper ocean waves against surface wind stress anomaly exerts a primary cause of El Niño-Southern Oscillation (ENSO) transition asymmetry. Externally, the asymmetrical capacitor effects of both Indian and Atlantic Oceans play some roles in driving the ENSO transition asymmetry via the interbasin interactions. The historical runs of Coupled Model Intercomparison Project Phase 5 show that the intermodel transition asymmetry is significantly correlated with the intermodel asymmetry in ocean wave response to surface wind forcing but not with that in the interbasin interactions. In addition, the El Niño-to-La Niña transition tendency was weaker in moderate global warming scenario runs (Representative Concentration Pathway 4.5) while slightly enhanced in strong warming scenario runs (Representative Concentration Pathway 8.5). Similar changes also appeared in the asymmetrical response of ocean waves against the surface wind forcing.

Southern states radiological emergency response laws and regulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-07-01

The purpose of this report is to provide a summary of the emergency response laws and regulations in place in the various states within the southern region for use by legislators, emergency response planners, the general public and all persons concerned about the existing legal framework for emergency response. SSEB expects to periodically update the report as necessary. Radiation protection regulations without emergency response provisions are not included in the summary.

Sensitivity of Antarctic sea ice to the Southern Annular Mode in coupled climate models

NASA Astrophysics Data System (ADS)

Holland, Marika M.; Landrum, Laura; Kostov, Yavor; Marshall, John

2017-09-01

We assess the sea ice response to Southern Annular Mode (SAM) anomalies for pre-industrial control simulations from the Coupled Model Intercomparison Project (CMIP5). Consistent with work by Ferreira et al. (J Clim 28:1206-1226, 2015. doi: 10.1175/JCLI-D-14-00313.1), the models generally simulate a two-timescale response to positive SAM anomalies, with an initial increase in ice followed by an eventual sea ice decline. However, the models differ in the cross-over time at which the change in ice response occurs, in the overall magnitude of the response, and in the spatial distribution of the response. Late twentieth century Antarctic sea ice trends in CMIP5 simulations are related in part to different modeled responses to SAM variability acting on different time-varying transient SAM conditions. This explains a significant fraction of the spread in simulated late twentieth century southern hemisphere sea ice extent trends across the model simulations. Applying the modeled sea ice response to SAM variability but driven by the observed record of SAM suggests that variations in the austral summer SAM, which has exhibited a significant positive trend, have driven a modest sea ice decrease. However, additional work is needed to narrow the considerable model uncertainty in the climate response to SAM variability and its implications for 20th-21st century trends.

Methods for Validation and Intercomparison of Remote Sensing and In situ Ice Water Measurements: Case Studies from CRYSTAL-FACE and Model Results

NASA Technical Reports Server (NTRS)

Sayres, D.S.; Pittman, J. V.; Smith, J. B.; Weinstock, E. M.; Anderson, J. G.; Heymsfield, G.; Li, L.; Fridlind, A.; Ackerman, A. S.

2004-01-01

Remote sensing observations, such as those from AURA, are necessary to understand the role of cirrus in determining the radiative and humidity budgets of the upper troposphere. Using these measurements quantitatively requires comparisons with in situ measurements that have previously been validated. However, a direct comparison of remote and in situ measurements is difficult due to the requirement that the spatial and temporal overlap be sufficient in order to guarantee that both instruments are measuring the same air parcel. A difficult as this might be for gas phase intercomparisons, cloud inhomogeneities significantly exacerbate the problem for cloud ice water content measurements. The CRYSTAL-FACE mission provided an opportunity to assess how well such intercomparisons can be performed and to establish flight plans that will be necessary for validation of future satellite instruments. During CRYSTAL-FACE, remote and in situ instruments were placed on different aircraft (NASA's ER-2 and WB-59, and the two planes flew in tandem so that the in situ payload flew in the field of view of the remote instruments. We show here that, even with this type of careful flight planning, it is not always possible to guarantee that remote and in situ instruments are viewing the same air parcel. We use ice water data derived from the in situ Harvard Total Water (HV-TW) instrument, and the remote Goddard Cloud Radar System (CRS) and show that agreement between HV-TW and CRS is a strong function of the horizontal separation and the time delay between the aircraft transects. We also use a cloud model to simulate possible trajectories through a cloud and evaluate the use of statistical analysis in determining the agreement between the two instruments. This type of analysis should guide flight planning for future intercomparison efforts, whether for aircraft or satellite-borne instrumentation.

The North American Carbon Program Multi-scale Synthesis and Terrestrial Model Intercomparison Project – Part 2: Environmental driver data

DOE PAGES

Wei, Yaxing; Liu, Shishi; Huntzinger, Deborah N.; ...

2014-12-05

Ecosystems are important and dynamic components of the global carbon cycle, and terrestrial biospheric models (TBMs) are crucial tools in further understanding of how terrestrial carbon is stored and exchanged with the atmosphere across a variety of spatial and temporal scales. Improving TBM skills, and quantifying and reducing their estimation uncertainties, pose significant challenges. The Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal multi-scale and multi-model intercomparison effort set up to tackle these challenges. The MsTMIP protocol prescribes standardized environmental driver data that are shared among model teams to facilitate model model and model observation comparisons. Inmore » this article, we describe the global and North American environmental driver data sets prepared for the MsTMIP activity to both support their use in MsTMIP and make these data, along with the processes used in selecting/processing these data, accessible to a broader audience. Based on project needs and lessons learned from past model intercomparison activities, we compiled climate, atmospheric CO 2 concentrations, nitrogen deposition, land use and land cover change (LULCC), C3 / C4 grasses fractions, major crops, phenology and soil data into a standard format for global (0.5⁰ x 0.5⁰ resolution) and regional (North American: 0.25⁰ x 0.25⁰ resolution) simulations. In order to meet the needs of MsTMIP, improvements were made to several of the original environmental data sets, by improving the quality, and/or changing their spatial and temporal coverage, and resolution. The resulting standardized model driver data sets are being used by over 20 different models participating in MsTMIP. Lastly, the data are archived at the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC, http://daac.ornl.gov) to provide long-term data management and distribution.« less

Real-time analysis of δ13C- and δD-CH4 in ambient air with laser spectroscopy: method development and first intercomparison results

NASA Astrophysics Data System (ADS)

Eyer, S.; Tuzson, B.; Popa, M. E.; van der Veen, C.; Röckmann, T.; Rothe, M.; Brand, W. A.; Fisher, R.; Lowry, D.; Nisbet, E. G.; Brennwald, M. S.; Harris, E.; Zellweger, C.; Emmenegger, L.; Fischer, H.; Mohn, J.

2015-08-01

In situ and simultaneous measurement of the three most abundant isotopologues of methane using mid-infrared laser absorption spectroscopy is demonstrated. A field-deployable, autonomous platform is realized by coupling a compact quantum cascade laser absorption spectrometer (QCLAS) to a preconcentration unit, called TRace gas EXtractor (TREX). This unit enhances CH4 mole fractions by a factor of up to 500 above ambient levels and quantitatively separates interfering trace gases such as N2O and CO2. The analytical precision of the QCLAS isotope measurement on the preconcentrated (750 ppm, parts-per-million, μmole/mole) methane is 0.1 and 0.5 ‰ for δ13C- and δD-CH4 at 10 min averaging time. Based on replicate measurements of compressed air during a two-week intercomparison campaign, the repeatability of the TREX-QCLAS was determined to be 0.19 and 1.9 ‰ for δ13C and δD-CH4, respectively. In this intercomparison campaign the new in situ technique is compared to isotope-ratio mass-spectrometry (IRMS) based on glass flask and bag sampling and real time CH4 isotope analysis by two commercially available laser spectrometers. Both laser-based analyzers were limited to methane mole fraction and δ13C-CH4 analysis, and only one of them, a cavity ring down spectrometer, was capable to deliver meaningful data for the isotopic composition. After correcting for scale offsets, the average difference between TREX-QCLAS data and bag/flask sampling-IRMS values are within the extended WMO compatibility goals of 0.2 and 5 ‰ for δ13C- and δD-CH4, respectively. Thus, the intercomparison also reveals the need for reference air samples with accurately determined isotopic composition of CH4 to further improve the interlaboratory compatibility.

Integrated watershed-scale response to climate change for selected basins across the United States

USGS Publications Warehouse

Markstrom, Steven L.; Hay, Lauren E.; Ward-Garrison, D. Christian; Risley, John C.; Battaglin, William A.; Bjerklie, David M.; Chase, Katherine J.; Christiansen, Daniel E.; Dudley, Robert W.; Hunt, Randall J.; Koczot, Kathryn M.; Mastin, Mark C.; Regan, R. Steven; Viger, Roland J.; Vining, Kevin C.; Walker, John F.

2012-01-01

A study by the U.S. Geological Survey (USGS) evaluated the hydrologic response to different projected carbon emission scenarios of the 21st century using a hydrologic simulation model. This study involved five major steps: (1) setup, calibrate and evaluated the Precipitation Runoff Modeling System (PRMS) model in 14 basins across the United States by local USGS personnel; (2) acquire selected simulated carbon emission scenarios from the World Climate Research Programme's Coupled Model Intercomparison Project; (3) statistical downscaling of these scenarios to create PRMS input files which reflect the future climatic conditions of these scenarios; (4) generate PRMS projections for the carbon emission scenarios for the 14 basins; and (5) analyze the modeled hydrologic response. This report presents an overview of this study, details of the methodology, results from the 14 basin simulations, and interpretation of these results. A key finding is that the hydrological response of the different geographical regions of the United States to potential climate change may be different, depending on the dominant physical processes of that particular region. Also considered is the tremendous amount of uncertainty present in the carbon emission scenarios and how this uncertainty propagates through the hydrologic simulations.

Intercomparison of general circulation models for hot extrasolar planets

NASA Astrophysics Data System (ADS)

Polichtchouk, I.; Cho, J. Y.-K.; Watkins, C.; Thrastarson, H. Th.; Umurhan, O. M.; de la Torre Juárez, M.

2014-02-01

We compare five general circulation models (GCMs) which have been recently used to study hot extrasolar planet atmospheres (BOB, CAM, IGCM, MITgcm, and PEQMOD), under three test cases useful for assessing model convergence and accuracy. Such a broad, detailed intercomparison has not been performed thus far for extrasolar planets study. The models considered all solve the traditional primitive equations, but employ different numerical algorithms or grids (e.g., pseudospectral and finite volume, with the latter separately in longitude-latitude and ‘cubed-sphere’ grids). The test cases are chosen to cleanly address specific aspects of the behaviors typically reported in hot extrasolar planet simulations: (1) steady-state, (2) nonlinearly evolving baroclinic wave, and (3) response to fast timescale thermal relaxation. When initialized with a steady jet, all models maintain the steadiness, as they should-except MITgcm in cubed-sphere grid. A very good agreement is obtained for a baroclinic wave evolving from an initial instability in pseudospectral models (only). However, exact numerical convergence is still not achieved across the pseudospectral models: amplitudes and phases are observably different. When subject to a typical ‘hot-Jupiter’-like forcing, all five models show quantitatively different behavior-although qualitatively similar, time-variable, quadrupole-dominated flows are produced. Hence, as have been advocated in several past studies, specific quantitative predictions (such as the location of large vortices and hot regions) by GCMs should be viewed with caution. Overall, in the tests considered here, pseudospectral models in pressure coordinate (PEBOB and PEQMOD) perform the best and MITgcm in cubed-sphere grid performs the worst.

The western Pacific monsoon in CMIP5 models: Model evaluation and projections

NASA Astrophysics Data System (ADS)

Brown, Josephine R.; Colman, Robert A.; Moise, Aurel F.; Smith, Ian N.

2013-11-01

ability of 35 models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) to simulate the western Pacific (WP) monsoon is evaluated over four representative regions around Timor, New Guinea, the Solomon Islands and Palau. Coupled model simulations are compared with atmosphere-only model simulations (with observed sea surface temperatures, SSTs) to determine the impact of SST biases on model performance. Overall, the CMIP5 models simulate the WP monsoon better than previous-generation Coupled Model Intercomparison Project Phase 3 (CMIP3) models, but some systematic biases remain. The atmosphere-only models are better able to simulate the seasonal cycle of zonal winds than the coupled models, but display comparable biases in the rainfall. The CMIP5 models are able to capture features of interannual variability in response to the El Niño-Southern Oscillation. In climate projections under the RCP8.5 scenario, monsoon rainfall is increased over most of the WP monsoon domain, while wind changes are small. Widespread rainfall increases at low latitudes in the summer hemisphere appear robust as a large majority of models agree on the sign of the change. There is less agreement on rainfall changes in winter. Interannual variability of monsoon wet season rainfall is increased in a warmer climate, particularly over Palau, Timor and the Solomon Islands. A subset of the models showing greatest skill in the current climate confirms the overall projections, although showing markedly smaller rainfall increases in the western equatorial Pacific. The changes found here may have large impacts on Pacific island countries influenced by the WP monsoon.

The Plumbing of Land Surface Models: Is Poor Performance a Result of Methodology or Data Quality?

NASA Technical Reports Server (NTRS)

Haughton, Ned; Abramowitz, Gab; Pitman, Andy J.; Or, Dani; Best, Martin J.; Johnson, Helen R.; Balsamo, Gianpaolo; Boone, Aaron; Cuntz, Matthais; Decharme, Bertrand;

Quality assessment concept of the World Data Center for Climate and its application to CMIP5 data

NASA Astrophysics Data System (ADS)

Stockhause, M.; Höck, H.; Toussaint, F.; Lautenschlager, M.

2012-08-01

The preservation of data in a high state of quality which is suitable for interdisciplinary use is one of the most pressing and challenging current issues in long-term archiving. For high volume data such as climate model data, the data and data replica are no longer stored centrally but distributed over several local data repositories, e.g. the data of the Climate Model Intercomparison Project Phase 5 (CMIP5). The most important part of the data is to be archived, assigned a DOI, and published according to the World Data Center for Climate's (WDCC) application of the DataCite regulations. The integrated part of WDCC's data publication process, the data quality assessment, was adapted to the requirements of a federated data infrastructure. A concept of a distributed and federated quality assessment procedure was developed, in which the workload and responsibility for quality control is shared between the three primary CMIP5 data centers: Program for Climate Model Diagnosis and Intercomparison (PCMDI), British Atmospheric Data Centre (BADC), and WDCC. This distributed quality control concept, its pilot implementation for CMIP5, and first experiences are presented. The distributed quality control approach is capable of identifying data inconsistencies and to make quality results immediately available for data creators, data users and data infrastructure managers. Continuous publication of new data versions and slow data replication prevents the quality control from check completion. This together with ongoing developments of the data and metadata infrastructure requires adaptations in code and concept of the distributed quality control approach.

An assessment of two automated snow water equivalent instruments during the WMO Solid Precipitation Intercomparison Experiment

NASA Astrophysics Data System (ADS)

Smith, Craig D.; Kontu, Anna; Laffin, Richard; Pomeroy, John W.

2017-01-01

During the World Meteorological Organization (WMO) Solid Precipitation Intercomparison Experiment (SPICE), automated measurements of snow water equivalent (SWE) were made at the Sodankylä (Finland), Weissfluhjoch (Switzerland) and Caribou Creek (Canada) SPICE sites during the northern hemispheric winters of 2013/14 and 2014/15. Supplementary intercomparison measurements were made at Fortress Mountain (Kananaskis, Canada) during the 2013/14 winter. The objectives of this analysis are to compare automated SWE measurements with a reference, comment on their performance and, where possible, to make recommendations on how to best use the instruments and interpret their measurements. Sodankylä, Caribou Creek and Fortress Mountain hosted a Campbell Scientific CS725 passive gamma radiation SWE sensor. Sodankylä and Weissfluhjoch hosted a Sommer Messtechnik SSG1000 snow scale. The CS725 operating principle is based on measuring the attenuation of soil emitted gamma radiation by the snowpack and relating the attenuation to SWE. The SSG1000 measures the mass of the overlying snowpack directly by using a weighing platform and load cell. Manual SWE measurements were obtained at the intercomparison sites on a bi-weekly basis over the accumulation-ablation periods using bulk density samplers. These manual measurements are considered to be the reference for the intercomparison. Results from Sodankylä and Caribou Creek showed that the CS725 generally overestimates SWE as compared to manual measurements by roughly 30-35 % with correlations (r2) as high as 0.99 for Sodankylä and 0.90 for Caribou Creek. The RMSE varied from 30 to 43 mm water equivalent (mm w.e.) and from 18 to 25 mm w.e. at Sodankylä and Caribou Creek, which had respective SWE maximums of approximately 200 and 120 mm w.e. The correlation at Fortress Mountain was 0.94 (RMSE of 48 mm w.e. with a maximum SWE of approximately 650 mm w.e.) with no systematic overestimation. The SSG1000 snow scale, having a different measurement principle, agreed quite closely with the manual measurements at Sodankylä and Weissfluhjoch throughout the periods when data were available (r2 as high as 0.99 and RMSE from 8 to 24 mm w.e. at Sodankylä and from 56 to 59 mm w.e. at Weissfluhjoch, where maximum SWE was approximately 850 mm w.e.). When the SSG1000 was compared to the CS725 at Sodankylä, the agreement was linear until the start of ablation when the positive bias in the CS725 increases substantially relative to the SSG1000. Since both Caribou Creek and Sodankylä have sandy soil, water from the snowpack readily infiltrates into the soil during melt, even if the soil is frozen. However, the CS725 does not differentiate this water from the unmelted snow. This issue can be identified, at least during the late spring ablation period, with soil moisture and temperature observations like those measured at Caribou Creek. With a less permeable soil and surface runoff, the increase in the instrument bias during ablation is not as significant, as shown by the Fortress Mountain intercomparison.

Projecting Antarctic ice discharge using response functions from SeaRISE ice-sheet models

NASA Astrophysics Data System (ADS)

Levermann, A.; Winkelmann, R.; Nowicki, S.; Fastook, J. L.; Frieler, K.; Greve, R.; Hellmer, H. H.; Martin, M. A.; Meinshausen, M.; Mengel, M.; Payne, A. J.; Pollard, D.; Sato, T.; Timmermann, R.; Wang, W. L.; Bindschadler, R. A.

2014-08-01

The largest uncertainty in projections of future sea-level change results from the potentially changing dynamical ice discharge from Antarctica. Basal ice-shelf melting induced by a warming ocean has been identified as a major cause for additional ice flow across the grounding line. Here we attempt to estimate the uncertainty range of future ice discharge from Antarctica by combining uncertainty in the climatic forcing, the oceanic response and the ice-sheet model response. The uncertainty in the global mean temperature increase is obtained from historically constrained emulations with the MAGICC-6.0 (Model for the Assessment of Greenhouse gas Induced Climate Change) model. The oceanic forcing is derived from scaling of the subsurface with the atmospheric warming from 19 comprehensive climate models of the Coupled Model Intercomparison Project (CMIP-5) and two ocean models from the EU-project Ice2Sea. The dynamic ice-sheet response is derived from linear response functions for basal ice-shelf melting for four different Antarctic drainage regions using experiments from the Sea-level Response to Ice Sheet Evolution (SeaRISE) intercomparison project with five different Antarctic ice-sheet models. The resulting uncertainty range for the historic Antarctic contribution to global sea-level rise from 1992 to 2011 agrees with the observed contribution for this period if we use the three ice-sheet models with an explicit representation of ice-shelf dynamics and account for the time-delayed warming of the oceanic subsurface compared to the surface air temperature. The median of the additional ice loss for the 21st century is computed to 0.07 m (66% range: 0.02-0.14 m; 90% range: 0.0-0.23 m) of global sea-level equivalent for the low-emission RCP-2.6 (Representative Concentration Pathway) scenario and 0.09 m (66% range: 0.04-0.21 m; 90% range: 0.01-0.37 m) for the strongest RCP-8.5. Assuming no time delay between the atmospheric warming and the oceanic subsurface, these values increase to 0.09 m (66% range: 0.04-0.17 m; 90% range: 0.02-0.25 m) for RCP-2.6 and 0.15 m (66% range: 0.07-0.28 m; 90% range: 0.04-0.43 m) for RCP-8.5. All probability distributions are highly skewed towards high values. The applied ice-sheet models are coarse resolution with limitations in the representation of grounding-line motion. Within the constraints of the applied methods, the uncertainty induced from different ice-sheet models is smaller than that induced by the external forcing to the ice sheets.

The Student Volunteer Army: a 'repeat emergent' emergency response organisation.

PubMed

Carlton, Sally; Mills, Colleen E

2017-10-01

This paper seeks to contribute to understanding of the factors associated with an effective emergent emergency response organisation and to provide new insights into this understudied area. It examines, through an analysis of a range of textual resources, the emergence and re-emergence of the Student Volunteer Army (SVA) during the devastating earthquakes in Canterbury, New Zealand, in 2010-11. This evaluation is conducted in relation to the four key features of an effective emergency response organisation: adaptability; direction; leadership; and communication. In addition, the paper aims to further understanding of 'emergency entrepreneurship' and thus of the values and strategies that underpin social entrepreneur organisations in times of normalcy. The paper concludes that the unique position of the SVA as a 'repeat emergent' emergency response organisation enabled it to innovate continually and to improve repeatedly its systems, relationships, and image, such that it exhibited features common to emergent and established emergency response organisations. © 2017 The Author(s). Disasters © Overseas Development Institute, 2017.

40 CFR 300.215 - Title III local emergency response plans.

Code of Federal Regulations, 2014 CFR

2014-07-01

... should be closely coordinated with applicable federal ACPs and state emergency response plans. (b... POLLUTION CONTINGENCY PLAN Planning and Preparedness § 300.215 Title III local emergency response plans... are codified at 40 CFR part 355. (a) Each LEPC is to prepare an emergency response plan in accordance...

40 CFR 300.215 - Title III local emergency response plans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... should be closely coordinated with applicable federal ACPs and state emergency response plans. (b... POLLUTION CONTINGENCY PLAN Planning and Preparedness § 300.215 Title III local emergency response plans... are codified at 40 CFR part 355. (a) Each LEPC is to prepare an emergency response plan in accordance...

40 CFR 300.215 - Title III local emergency response plans.

Code of Federal Regulations, 2011 CFR

2011-07-01

... should be closely coordinated with applicable federal ACPs and state emergency response plans. (b... POLLUTION CONTINGENCY PLAN Planning and Preparedness § 300.215 Title III local emergency response plans... are codified at 40 CFR part 355. (a) Each LEPC is to prepare an emergency response plan in accordance...

29 CFR 2700.24 - Emergency response plan dispute proceedings.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 9 2013-07-01 2013-07-01 false Emergency response plan dispute proceedings. 2700.24... COMMISSION PROCEDURAL RULES Contests of Citations and Orders § 2700.24 Emergency response plan dispute... operator's emergency response plan, or any refusal by the Secretary to approve such a plan. Any referral...

29 CFR 2700.24 - Emergency response plan dispute proceedings.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 9 2010-07-01 2010-07-01 false Emergency response plan dispute proceedings. 2700.24... COMMISSION PROCEDURAL RULES Contests of Citations and Orders § 2700.24 Emergency response plan dispute... operator's emergency response plan, or any refusal by the Secretary to approve such a plan. Any referral...

40 CFR 300.215 - Title III local emergency response plans.

Code of Federal Regulations, 2013 CFR

2013-07-01

... should be closely coordinated with applicable federal ACPs and state emergency response plans. (b... POLLUTION CONTINGENCY PLAN Planning and Preparedness § 300.215 Title III local emergency response plans... are codified at 40 CFR part 355. (a) Each LEPC is to prepare an emergency response plan in accordance...

40 CFR 300.215 - Title III local emergency response plans.

Code of Federal Regulations, 2012 CFR

2012-07-01

... should be closely coordinated with applicable federal ACPs and state emergency response plans. (b... POLLUTION CONTINGENCY PLAN Planning and Preparedness § 300.215 Title III local emergency response plans... are codified at 40 CFR part 355. (a) Each LEPC is to prepare an emergency response plan in accordance...

High LET, passive space radiation dosimetry and spectrometry

NASA Technical Reports Server (NTRS)

Benton, E. V.; Frank, A. L.; Benton, E. R.; Keegan, R. P.; Frigo, L. A.; Sanner, D.; Rowe, V.

1995-01-01

The development of high linear energy transfer (LET), passive radiation dosimetry and spectrometry is needed for the purpose of accurate determination of equivalent doses and assessment of health risks to astronauts on long duration missions. Progress in the following research areas is summerized: intercomparisons of cosmic ray equivalent dose and LET spectra measurements between STS missions and between astronauts; increases LET spectra measurement accuracy with ATAS; space radiation measurements for intercomparisons of passive (PNTD, TLD, TRND, Emulsion) and active (TEPC, RME-111) dosimeters; interaction of cosmic ray particles with nuclei in matter; radiation measurements after long duration space exposures; ground based dosimeter calibrations; neutron detector calibrations; radiation measurements on Soviet/Russian spacecraft; space radiation measurements under thin shielding; and space radiation.

Earth orientation from lunar laser ranging and an error analysis of polar motion services

NASA Technical Reports Server (NTRS)

Dickey, J. O.; Newhall, X. X.; Williams, J. G.

1985-01-01

Lunar laser ranging (LLR) data are obtained on the basis of the timing of laser pulses travelling from observatories on earth to retroreflectors placed on the moon's surface during the Apollo program. The modeling and analysis of the LLR data can provide valuable insights into earth's dynamics. The feasibility to model accurately the lunar orbit over the full 13-year observation span makes it possible to conduct relatively long-term studies of variations in the earth's rotation. A description is provided of general analysis techniques, and the calculation of universal time (UT1) from LLR is discussed. Attention is also given to a summary of intercomparisons with different techniques, polar motion results and intercomparisons, and a polar motion error analysis.

Test Bed Doppler Wind Lidar and Intercomparison Facility At NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Kavaya, Michael J.; Koch, Grady J.; Petros, Mulugeta; Barnes, Bruce W.; Beyon, Jeffrey; Amzajerdian, Farzin; Yu, Ji-Rong; Singh, Upendra N.

2004-01-01

State of the art 2-micron lasers and other lidar components under development by NASA are being demonstrated and validated in a mobile test bed Doppler wind lidar. A lidar intercomparison facility has been developed to ensure parallel alignment of up to 4 Doppler lidar systems while measuring wind. Investigations of the new components; their operation in a complete system; systematic and random errors; the hybrid (joint coherent and direct detection) approach to global wind measurement; and atmospheric wind behavior are planned. Future uses of the VALIDAR (VALIDation LIDAR) mobile lidar may include comparison with the data from an airborne Doppler wind lidar in preparation for validation by the airborne system of an earth orbiting Doppler wind lidar sensor.

Intercomparison of analytical methods for arsenic speciation in human urine.

PubMed Central

Crecelius, E; Yager, J

1997-01-01

An intercomparison exercise was conducted for the quantification of arsenic species in spiked human urine. The primary objective of the exercise was to determine the variance among laboratories in the analysis of arsenic species such as inorganic As (As+3 and As+5), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA). Laboratories that participated had previous experience with arsenic speciation analysis. The results of this interlaboratory comparison are encouraging. There is relatively good agreement on the concentrations of these arsenic species in urine at concentrations that are relevant to research on the metabolism of arsenic in humans and other mammals. Both the accuracy and precision are relatively poor for arsenic concentrations of less than about 5 micrograms/l. PMID:9288500

Results of the August 1977 Soviet and American meterological rocketsonde intercomparison held at Wallops Island, Virginia

NASA Technical Reports Server (NTRS)

Schmidlin, F. J.; Duke, J. R.; Ivanovsky, A. I.; Chernyshenko, Y. M.

1980-01-01

A coordinated program of rocketsonde investigations along about 60 deg E and 70 deg W between the United States and U.S.S.R. is discussed. The rocketsonde instruments used by the U.S. and U.S.S.R. were compared and the results are presented. The U.S. Super Loki Datasonde and the U.S.S.R. M100B rocketsonde are discussed. Results indicate that the U.S/U.S.S.R. rocketsonde measurement agreement improved since the 1973 intercomparisons. It was learned that the mean of the differences of the temperatures compare to within 6 C at about 60 km and to within 2 C near 50 km. Wind measurements were also found to agree.

Emergency Response of Iranian Hospitals Against Disasters: A Practical Framework for Improvement.

PubMed

Janati, Ali; Sadeghi-Bazargani, Homayoun; Hasanpoor, Edris; Sokhanvar, Mobin; HaghGoshyie, Elaheh; Salehi, Abdollah

2018-04-01

Hospital emergency management is a continuous process that requires monolithic integration of planning and response attempts with local and national schemes. The aim of the current study is to evaluate emergency response by hospitals against potential disasters in Tabriz, north-west Iran. A cross-sectional study was conducted in the city of Tabriz, in Iran, in 2016. The study population included all hospitals in Tabriz. A total of 18 hospitals were assessed. The hospital emergency response checklist was used to collect data. Tool components included command and control, communication, safety and security, triage, surge capacity, continuity of essential services, human resources, logistics and supply management, and post-disaster recovery. Data entry and analysis were carried out using SPSS software (version 20). The results showed that the emergency response rate of hospitals was 54.26% in Tabriz. The lowest response rates were for Shafaa hospital (18.89%) and the highest response rates were for Razi Hospital (91.67%). The components of hospital emergency response were assessed to be between 48.07% (surge capacity) and 58.95% (communication). On the basis of the World Health Organization checklist, the emergency response rate for hospitals in Tabriz was only 54.26%. Therefore, hospital emergency responses against disasters have to be improved and must be made to reach 100%. It is essential to design a comprehensive framework for hospital emergency response. (Disaster Med Public Health Preparedness. 2018;12:166-171).

Tropospheric jet response to Antarctic ozone depletion: An update with Chemistry-Climate Model Initiative (CCMI) models

NASA Astrophysics Data System (ADS)

Son, Seok-Woo; Han, Bo-Reum; Garfinkel, Chaim I.; Kim, Seo-Yeon; Park, Rokjin; Abraham, N. Luke; Akiyoshi, Hideharu; Archibald, Alexander T.; Butchart, N.; Chipperfield, Martyn P.; Dameris, Martin; Deushi, Makoto; Dhomse, Sandip S.; Hardiman, Steven C.; Jöckel, Patrick; Kinnison, Douglas; Michou, Martine; Morgenstern, Olaf; O’Connor, Fiona M.; Oman, Luke D.; Plummer, David A.; Pozzer, Andrea; Revell, Laura E.; Rozanov, Eugene; Stenke, Andrea; Stone, Kane; Tilmes, Simone; Yamashita, Yousuke; Zeng, Guang

2018-05-01

The Southern Hemisphere (SH) zonal-mean circulation change in response to Antarctic ozone depletion is re-visited by examining a set of the latest model simulations archived for the Chemistry-Climate Model Initiative (CCMI) project. All models reasonably well reproduce Antarctic ozone depletion in the late 20th century. The related SH-summer circulation changes, such as a poleward intensification of westerly jet and a poleward expansion of the Hadley cell, are also well captured. All experiments exhibit quantitatively the same multi-model mean trend, irrespective of whether the ocean is coupled or prescribed. Results are also quantitatively similar to those derived from the Coupled Model Intercomparison Project phase 5 (CMIP5) high-top model simulations in which the stratospheric ozone is mostly prescribed with monthly- and zonally-averaged values. These results suggest that the ozone-hole-induced SH-summer circulation changes are robust across the models irrespective of the specific chemistry-atmosphere-ocean coupling.

New Results from the Geoengineering Model Intercomparison Project (GeoMIP)

NASA Astrophysics Data System (ADS)

Robock, A.; Kravitz, B.

2013-12-01

The Geoengineering Model Intercomparison Project (GeoMIP) was designed to determine robust climate system model responses to Solar Radiation Management (SRM). While mitigation (reducing greenhouse gases emissions) is the most effective way of reducing future climate change, SRM (the deliberate modification of incoming solar radiation) has been proposed as a means of temporarily alleviating some of the effects of global warming. For society to make informed decisions as to whether SRM should ever be implemented, information is needed on the benefits, risks, and side effects, and GeoMIP seeks to aid in that endeavor. GeoMIP has organized four standardized climate model simulations involving reduction of insolation or increased amounts of stratospheric sulfate aerosols to counteract increasing greenhouse gases. Thirteen comprehensive atmosphere-ocean general circulation models have participated in the project so far. GeoMIP is a 'CMIP Coordinated Experiment' as part of the Climate Model Intercomparison Project 5 (CMIP5) and has been endorsed by SPARC (Stratosphere-troposphere Processes And their Role in Climate). GeoMIP has held three international workshops and has produced a number of recent journal articles. GeoMIP has found that if increasing greenhouse gases could be counteracted with insolation reduction, the global average temperature could be kept constant, but global average precipitation would reduce, particularly in summer monsoon regions around the world. Temperature changes would also not be uniform. The tropics would cool, but high latitudes would warm, with continuing, but reduced sea ice and ice sheet melting. Temperature extremes would still increase, but not as much as without SRM. If SRM were halted all at once, there would be rapid temperature and precipitation increases at 5-10 times the rates from gradual global warming. SRM combined with CO2 fertilization would have small impacts on rice production in China, but would increase maize production. SRM using stratospheric aerosols would reduce ozone and enhance surface UV-B radiation, but the details depend on the size distribution of the aerosols, and the complex interaction between upwelling of ozone-poor air in the tropics, suppression of the NOx cycle, and increases of surface area density. While GeoMIP has improved confidence in the expected climate effects of geoengineering in several key areas, it has also highlighted several important research gaps, such as the effects on terrestrial net primary productivity and the importance of the CO2 physiological effect in determining the hydrologic cycle response to geoengineering. Future efforts will endeavor to address these gaps, as well as encourage cooperation with the chemistry modeling communities, the impact assessment communities (including on agriculture and ecosystems), and other groups interested in model output. We are organizing new GeoMIP experiments that address the suggestion that SRM be implemented by marine cloud brightening, and are proposing that GeoMIP be an integral part of the design of the CMIP6 project.

Science in Emergency Response at CDC: Structure and Functions.

PubMed

Iskander, John; Rose, Dale A; Ghiya, Neelam D

2017-09-01

Recent high-profile activations of the US Centers for Disease Control and Prevention (CDC) Emergency Operations Center (EOC) include responses to the West African Ebola and Zika virus epidemics. Within the EOC, emergency responses are organized according to the Incident Management System, which provides a standardized structure and chain of command, regardless of whether the EOC activation occurs in response to an outbreak, natural disaster, or other type of public health emergency. By embedding key scientific roles, such as the associate director for science, and functions within a Scientific Response Section, the current CDC emergency response structure ensures that both urgent and important science issues receive needed attention. Key functions during emergency responses include internal coordination of scientific work, data management, information dissemination, and scientific publication. We describe a case example involving the ongoing Zika virus response that demonstrates how the scientific response structure can be used to rapidly produce high-quality science needed to answer urgent public health questions and guide policy. Within the context of emergency response, longer-term priorities at CDC include both streamlining administrative requirements and funding mechanisms for scientific research.

49 CFR 1.45 - Delegations to the Director of the Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Intelligence, Security and Emergency Response. 1.45 Section 1.45 Transportation Office of the Secretary of... Delegations to the Director of the Office of Intelligence, Security and Emergency Response. The Director of Intelligence, Security, and Emergency Response is delegated authority to: (a) Carry out the functions related...

49 CFR 1.45 - Delegations to the Director of the Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Intelligence, Security and Emergency Response. 1.45 Section 1.45 Transportation Office of the Secretary of... Delegations to the Director of the Office of Intelligence, Security and Emergency Response. The Director of Intelligence, Security, and Emergency Response is delegated authority to: (a) Carry out the functions related...

49 CFR 1.45 - Delegations to the Director of the Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Intelligence, Security and Emergency Response. 1.45 Section 1.45 Transportation Office of the Secretary of... Delegations to the Director of the Office of Intelligence, Security and Emergency Response. The Director of Intelligence, Security, and Emergency Response is delegated authority to: (a) Carry out the functions related...

Multicentre validation of IMRT pre-treatment verification: comparison of in-house and external audit.

PubMed

Jornet, Núria; Carrasco, Pablo; Beltrán, Mercè; Calvo, Juan Francisco; Escudé, Lluís; Hernández, Victor; Quera, Jaume; Sáez, Jordi

2014-09-01

We performed a multicentre intercomparison of IMRT optimisation and dose planning and IMRT pre-treatment verification methods and results. The aims were to check consistency between dose plans and to validate whether in-house pre-treatment verification results agreed with those of an external audit. Participating centres used two mock cases (prostate and head and neck) for the intercomparison and audit. Compliance to dosimetric goals and total number of MU per plan were collected. A simple quality index to compare the different plans was proposed. We compared gamma index pass rates using the centre's equipment and methodology to those of an external audit. While for the prostate case, all centres fulfilled the dosimetric goals and plan quality was homogeneous, that was not the case for the head and neck case. The number of MU did not correlate with the plan quality index. Pre-treatment verifications results of the external audit did not agree with those of the in-house measurements for two centres: being within tolerance for in-house measurements and unacceptable for the audit or the other way round. Although all plans fulfilled dosimetric constraints, plan quality is highly dependent on the planner expertise. External audits are an excellent tool to detect errors in IMRT implementation and cannot be replaced by intercomparison using results obtained by centres. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Introduction to the SPARC Reanalysis Intercomparison Project (S-RIP) and overview of the reanalysis systems

NASA Astrophysics Data System (ADS)

Fujiwara, Masatomo; Wright, Jonathon S.; Manney, Gloria L.; Gray, Lesley J.; Anstey, James; Birner, Thomas; Davis, Sean; Gerber, Edwin P.; Harvey, V. Lynn; Hegglin, Michaela I.; Homeyer, Cameron R.; Knox, John A.; Krüger, Kirstin; Lambert, Alyn; Long, Craig S.; Martineau, Patrick; Molod, Andrea; Monge-Sanz, Beatriz M.; Santee, Michelle L.; Tegtmeier, Susann; Chabrillat, Simon; Tan, David G. H.; Jackson, David R.; Polavarapu, Saroja; Compo, Gilbert P.; Dragani, Rossana; Ebisuzaki, Wesley; Harada, Yayoi; Kobayashi, Chiaki; McCarty, Will; Onogi, Kazutoshi; Pawson, Steven; Simmons, Adrian; Wargan, Krzysztof; Whitaker, Jeffrey S.; Zou, Cheng-Zhi

2017-01-01

The climate research community uses atmospheric reanalysis data sets to understand a wide range of processes and variability in the atmosphere, yet different reanalyses may give very different results for the same diagnostics. The Stratosphere-troposphere Processes And their Role in Climate (SPARC) Reanalysis Intercomparison Project (S-RIP) is a coordinated activity to compare reanalysis data sets using a variety of key diagnostics. The objectives of this project are to identify differences among reanalyses and understand their underlying causes, to provide guidance on appropriate usage of various reanalysis products in scientific studies, particularly those of relevance to SPARC, and to contribute to future improvements in the reanalysis products by establishing collaborative links between reanalysis centres and data users. The project focuses predominantly on differences among reanalyses, although studies that include operational analyses and studies comparing reanalyses with observations are also included when appropriate. The emphasis is on diagnostics of the upper troposphere, stratosphere, and lower mesosphere. This paper summarizes the motivation and goals of the S-RIP activity and extensively reviews key technical aspects of the reanalysis data sets that are the focus of this activity. The special issue The SPARC Reanalysis Intercomparison Project (S-RIP) in this journal serves to collect research with relevance to the S-RIP in preparation for the publication of the planned two (interim and full) S-RIP reports.

The CMIP6 Sea-Ice Model Intercomparison Project (SIMIP): Understanding sea ice through climate-model simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Notz, Dirk; Jahn, Alexandra; Holland, Marika

A better understanding of the role of sea ice for the changing climate of our planet is the central aim of the diagnostic Coupled Model Intercomparison Project 6 (CMIP6)-endorsed Sea-Ice Model Intercomparison Project (SIMIP). To reach this aim, SIMIP requests sea-ice-related variables from climate-model simulations that allow for a better understanding and, ultimately, improvement of biases and errors in sea-ice simulations with large-scale climate models. This then allows us to better understand to what degree CMIP6 model simulations relate to reality, thus improving our confidence in answering sea-ice-related questions based on these simulations. Furthermore, the SIMIP protocol provides a standardmore » for sea-ice model output that will streamline and hence simplify the analysis of the simulated sea-ice evolution in research projects independent of CMIP. To reach its aims, SIMIP provides a structured list of model output that allows for an examination of the three main budgets that govern the evolution of sea ice, namely the heat budget, the momentum budget, and the mass budget. Furthermore, we explain the aims of SIMIP in more detail and outline how its design allows us to answer some of the most pressing questions that sea ice still poses to the international climate-research community.« less

The CMIP6 Sea-Ice Model Intercomparison Project (SIMIP): Understanding sea ice through climate-model simulations

DOE PAGES

Notz, Dirk; Jahn, Alexandra; Holland, Marika; ...

2016-09-23

A better understanding of the role of sea ice for the changing climate of our planet is the central aim of the diagnostic Coupled Model Intercomparison Project 6 (CMIP6)-endorsed Sea-Ice Model Intercomparison Project (SIMIP). To reach this aim, SIMIP requests sea-ice-related variables from climate-model simulations that allow for a better understanding and, ultimately, improvement of biases and errors in sea-ice simulations with large-scale climate models. This then allows us to better understand to what degree CMIP6 model simulations relate to reality, thus improving our confidence in answering sea-ice-related questions based on these simulations. Furthermore, the SIMIP protocol provides a standardmore » for sea-ice model output that will streamline and hence simplify the analysis of the simulated sea-ice evolution in research projects independent of CMIP. To reach its aims, SIMIP provides a structured list of model output that allows for an examination of the three main budgets that govern the evolution of sea ice, namely the heat budget, the momentum budget, and the mass budget. Furthermore, we explain the aims of SIMIP in more detail and outline how its design allows us to answer some of the most pressing questions that sea ice still poses to the international climate-research community.« less

Ice nucleating particles measured during the laboratory and field intercomparisons FIN-2 and FIN-3 by the diffusion chamber FRIDGE

NASA Astrophysics Data System (ADS)

Weber, Daniel; Schrod, Jann; Curtius, Joachim; Haunold, Werner; Thomson, Erik; Bingemer, Heinz

2016-04-01

The measurement of atmospheric ice nucleating particles (INP) is still challenging. In the absence of easily applicable INP standards the intercomparison of different methods during collaborative laboratory and field workshops is a valuable tool that can shine light on the performance of individual methods for the measurement of INP [1]. FIN-2 was conducted in March 2015 at the AIDA facility in Karlsruhe as an intercomparison of mobile instruments for measuring INP [2]. FIN-3 was a field campaign at the Desert Research Institutes Storm Peak Laboratory in Colorado in September 2015 [3]. The FRankfurt Ice nucleation Deposition freezinG Experiment (FRIDGE) participated in both experiments. FRIDGE measures ice nucleating particles by electrostatic precipitation of aerosol particles onto Si-wafers in a collection unit, followed by activation, growth, and optical detection of ice crystals on the substrate in an isostatic diffusion chamber [4,5]. We will present and discuss results of our measurements of deposition/condensation INP and of immersion INP with FRIDGE during FIN-2 and FIN-3. Acknowledgements: The valuable contributions of the FIN organizers and their institutions, and of the FIN Workshop Science team are gratefully acknowledged. Our work was supported by Deutsche Forschungsgemeinschaft (DFG) under the Research Unit FOR 1525 (INUIT) and the EU FP7-ENV- 2013 BACCHUS project under Grant Agreement 603445.

The Joint Experiment for Crop Assessment and Monitoring (JECAM): Synthetic Aperture Radar (SAR) Inter-Comparison Experiment

NASA Astrophysics Data System (ADS)

Dingle Robertson, L.; Hosseini, M.; Davidson, A. M.; McNairn, H.

2017-12-01

The Joint Experiment for Crop Assessment and Monitoring (JECAM) is the research and development branch of GEOGLAM (Group on Earth Observations Global Agricultural Monitoring), a G20 initiative to improve the global monitoring of agriculture through the use of Earth Observation (EO) data and remote sensing. JECAM partners represent a diverse network of researchers collaborating towards a set of best practices and recommendations for global agricultural analysis using EO data, with well monitored test sites covering a wide range of agriculture types, cropping systems and climate regimes. Synthetic Aperture Radar (SAR) for crop inventory and condition monitoring offers many advantages particularly the ability to collect data under cloudy conditions. The JECAM SAR Inter-Comparison Experiment is a multi-year, multi-partner project that aims to compare global methods for (1) operational SAR & optical; multi-frequency SAR; and compact polarimetry methods for crop monitoring and inventory, and (2) the retrieval of Leaf Area Index (LAI) and biomass estimations using models such as the Water Cloud Model (WCM) employing single frequency SAR; multi-frequency SAR; and compact polarimetry. The results from these activities will be discussed along with an examination of the requirements of a global experiment including best-date determination for SAR data acquisition, pre-processing techniques, in situ data sharing, model development and statistical inter-comparison of the results.

Intercomparison of global, ultraviolet B and A radiation measurements in the Dead Sea region (Ein Bokek) and Beer Sheva.

PubMed

Kushelevsky, A P; Kudish, A I

1996-07-01

Thousands of patients suffering from psoriasis have been treated successfully in the Dead Sea area by climatological methods, without medication. This high rate of success, measured in terms of partial to complete plaque clearance and reported to exceed 85% after 3-4 weeks of treatment, has been assumed to be associated with a unique ultraviolet (UV) radiation environment present in the Dead Sea region. In order to broaden our knowledge of the UV radiation environment at the Dead Sea, continuous monitoring of UV (both B and A) and global radiation has recently been initiated at two sites--Ein Bokek (located in the vicinity of the Dead Sea 375 m below mean sea level) and Beer Sheva (315 m above mean sea level)--to facilitate an intercomparison of their respective radiation intensities. The results of the first year of a detailed study of the global, UVB and UVA radiation intensities measured at both sites are summarized and reported in terms of the monthly average daily, average midday (11:00-13:00) and the corresponding maximum values. The radiation data for clear days (based upon the absolute magnitude of the global radiation) were also analyzed to perform an intercomparison between Ein Bokek and Beer Sheva for a winter month and a summer month for which all three types of radiation data were available at both sites.

Bilateral Comparison of Mercury and Gallium Fixed-Point Cells Using Standard Platinum Resistance Thermometer

NASA Astrophysics Data System (ADS)

Bojkovski, J.; Veliki, T.; Zvizdić, D.; Drnovšek, J.

2011-08-01

The objective of project EURAMET 1127 (Bilateral comparison of triple point of mercury and melting point of gallium) in the field of thermometry is to compare realization of a triple point of mercury (-38.8344 °C) and melting point of gallium (29.7646 °C) between the Slovenian national laboratory MIRS/UL-FE/LMK and the Croatian national laboratory HMI/FSB-LPM using a long-stem 25 Ω standard platinum resistance thermometer (SPRT). MIRS/UL/FE-LMK participated in a number of intercomparisons on the level of EURAMET. On the other hand, the HMI/LPM-FSB laboratory recently acquired new fixed-point cells which had to be evaluated in the process of intercomparisons. A quartz-sheathed SPRT has been selected and calibrated at HMI/LPM-FSB at the triple point of mercury, the melting point of gallium, and the water triple point. A second set of measurements was made at MIRS/UL/FE-LMK. After its return, the SPRT was again recalibrated at HMI/LPM-FSB. In the comparison, the W value of the SPRT has been used. Results of the bilateral intercomparison confirmed that the new gallium cell of the HMI/LPM-FSB has a value that is within uncertainty limits of both laboratories that participated in the exercise, while the mercury cell experienced problems. After further research, a small leakage in the mercury fixed-point cell has been found.

International Intercomparison of Specific Absorption Rates in a Flat Absorbing Phantom in the Near-Field of Dipole Antennas

PubMed Central

Davis, Christopher C.; Beard, Brian B.; Tillman, Ahlia; Rzasa, John; Merideth, Eric; Balzano, Quirino

2018-01-01

This paper reports the results of an international intercomparison of the specific absorption rates (SARs) measured in a flat-bottomed container (flat phantom), filled with human head tissue simulant fluid, placed in the near-field of custom-built dipole antennas operating at 900 and 1800 MHz, respectively. These tests of the reliability of experimental SAR measurements have been conducted as part of a verification of the ways in which wireless phones are tested and certified for compliance with safety standards. The measurements are made using small electric-field probes scanned in the simulant fluid in the phantom to record the spatial SAR distribution. The intercomparison involved a standard flat phantom, antennas, power meters, and RF components being circulated among 15 different governmental and industrial laboratories. At the conclusion of each laboratory’s measurements, the following results were communicated to the coordinators: Spatial SAR scans at 900 and 1800 MHz and 1 and 10 g maximum spatial SAR averages for cubic volumes at 900 and 1800 MHz. The overall results, given as meanstandard deviation, are the following: at 900 MHz, 1 g average 7.850.76; 10 g average 5.160.45; at 1800 MHz, 1 g average 18.44 ± 1.65; 10 g average 10.14 ± 0.85, all measured in units of watt per kilogram, per watt of radiated power. PMID:29520117

Interactions between Antarctic sea ice and large-scale atmospheric modes in CMIP5 models

NASA Astrophysics Data System (ADS)

Schroeter, Serena; Hobbs, Will; Bindoff, Nathaniel L.

2017-03-01

The response of Antarctic sea ice to large-scale patterns of atmospheric variability varies according to sea ice sector and season. In this study, interannual atmosphere-sea ice interactions were explored using observations and reanalysis data, and compared with simulated interactions by models in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Simulated relationships between atmospheric variability and sea ice variability generally reproduced the observed relationships, though more closely during the season of sea ice advance than the season of sea ice retreat. Atmospheric influence on sea ice is known to be strongest during advance, and it appears that models are able to capture the dominance of the atmosphere during advance. Simulations of ocean-atmosphere-sea ice interactions during retreat, however, require further investigation. A large proportion of model ensemble members overestimated the relative importance of the Southern Annular Mode (SAM) compared with other modes of high southern latitude climate, while the influence of tropical forcing was underestimated. This result emerged particularly strongly during the season of sea ice retreat. The zonal patterns of the SAM in many models and its exaggerated influence on sea ice overwhelm the comparatively underestimated meridional influence, suggesting that simulated sea ice variability would become more zonally symmetric as a result. Across the seasons of sea ice advance and retreat, three of the five sectors did not reveal a strong relationship with a pattern of large-scale atmospheric variability in one or both seasons, indicating that sea ice in these sectors may be influenced more strongly by atmospheric variability unexplained by the major atmospheric modes, or by heat exchange in the ocean.

A multilinear regression methodology to analyze the effect of atmospheric and surface forcing on Arctic clouds

NASA Astrophysics Data System (ADS)

Boeke, R.; Taylor, P. C.; Li, Y.

2017-12-01

Arctic cloud amount as simulated in CMIP5 models displays large intermodel spread- models disagree on the processes important for cloud formation as well as the radiative impact of clouds. The radiative response to cloud forcing can be better assessed when the drivers of Arctic cloud formation are known. Arctic cloud amount (CA) is a function of both atmospheric and surface conditions, and it is crucial to separate the influences of unique processes to understand why the models are different. This study uses a multilinear regression methodology to determine cloud changes using 3 variables as predictors: lower tropospheric stability (LTS), 500-hPa vertical velocity (ω500), and sea ice concentration (SIC). These three explanatory variables were chosen because their effects on clouds can be attributed to unique climate processes: LTS is a thermodynamic indicator of the relationship between clouds and atmospheric stability, SIC determines the interaction between clouds and the surface, and ω500 is a metric for dynamical change. Vertical, seasonal profiles of necessary variables are obtained from the Coupled Model Intercomparison Project 5 (CMIP5) historical simulation, an ocean-atmosphere couple model forced with the best-estimate natural and anthropogenic radiative forcing from 1850-2005, and statistical significance tests are used to confirm the regression equation. A unique heuristic model will be constructed for each climate model and for observations, and models will be tested by their ability to capture the observed cloud amount and behavior. Lastly, the intermodel spread in Arctic cloud amount will be attributed to individual processes, ranking the relative contributions of each factor to shed light on emergent constraints in the Arctic cloud radiative effect.

44 CFR 323.3 - Responsibilities.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) § 323.3 Responsibilities. (a) As stated in The National Plan for Emergency Preparedness, the direction... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Responsibilities. 323.3 Section 323.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF...

Detecting climate change oriented and human induced changes in stream temperature across the Southeastern U.S.

NASA Astrophysics Data System (ADS)

Zhang, X.; Voisin, N.; Cheng, Y.; Niemeyer, R. J.; Nijssen, B.; Yearsley, J. R.; Zhou, T.

2017-12-01

In many areas, climate change is expected to alter the flow regime and increase stream temperature, especially during summer low flow periods. During these low flow periods, water management increases flows in order to sustain human activities such as water for irrigation and hydroelectric power generation. Water extraction from rivers during warm season can increase stream temperature while reservoir regulation may cool downstream river temperatures by releasing cool water from deep layers. Thus, it is reasonable to hypothesize that water management changes the sensitivity of the stream temperature regime to climate change when compared to unmanaged resources. The time of emergence of change refers to the point in time when observations, or model simulations, show statistically significant changes from a given baseline period, i.e. above natural variability. Here we aim to address two questions by investigating the time of emergence of changes in stream temperature in the southeastern United States: what is the sensitivity of stream temperature under regulated flow conditions to climate change and what is the contribution of water management in increasing or decreasing stream temperature sensitivity to climate change. We simulate regulated flow by using runoff from the Variable Infiltration Capacity (VIC) macroscale hydrological model as input into a large scale river routing and reservoir model MOSART-WM. The River Basin Model (RBM), a distributed stream temperature model, includes a two-layer thermal stratification module to simulate stream temperature in regulated river systems. We evaluate the timing of emergence of changes in flow and stream temperature based on climate projections from two representative concentration pathways (RCPs; RCP4.5 and RCP8.5) from the Coupled Model Intercomparison Project Phase 5 (CMIP5). We analyze the difference in emergence of change between natural and regulated streamflow. Insights will be provided toward applications for multiple sectors of activities including electrical resources adequacy studies over the southeastern U.S.

Intercomparison of six fast-response sensors for the eddy-covariance flux measurement of nitrous oxide over agricultural grassland

NASA Astrophysics Data System (ADS)

Nemitz, Eiko; Famulari, Daniela; Ibrom, Andreas; Vermeulen, Alex; Hensen, Arjan; van den Bulk, Pim; Loubet, Benjamin; Laville, Patricia; Mammarella, Ivan; Haapanala, Sami; Lohila, Annalea; Laurila, Tuomas; Eva, Rabot; Laborde, Marie; Cowan, Nicholas; Anderson, Margaret; Helfter, Carole

2015-04-01

Nitrous oxide (N2O) is the third most important greenhouse gas and its terrestrial budget remains poorly constraint, with bottom up and top down estimates of country emissions often disagreeing by more than a factor of two. Whilst the measurements of the biosphere / atmosphere exchange of CO2 with micrometeorological methods is commonplace, emissions of CH4 and N2O are more commonly measured with enclosure techniques due to limitations in fast-response sensors with good signal-to-noise characteristics. Recent years have seen the development of a range of instruments based on optical spectroscopy. This started in the early 1990s with instruments based on lead salt lasers, which had temperamental long-term characteristics. More recent developments in quantum cascade lasers has lead to increasingly stable instruments, initially based on pulsed, later on continuous wave lasers. Within the context of the European FP7 Infrastructure Project InGOS ('Integrated non-CO2 Greenhouse gas Observing System'), we conducted an intercomparison of six fast response sensors for N2O: three more or less identical instruments based on off-axis Integrated Cavity Optical Spectrocopy (ICOS) (Los Gatos Research Inc.) and three instruments based on quantum cascade laser absorption spectrometry (Aerodyne Research Inc.): one older generation pulsed instrument (p-QCL) and two of the latest generation of compact continuous wave instruments (cw-QCL), operating at two different wavelengths. One of the ICOS instruments was operated with an inlet drier. In addition, the campaign was joined by a relaxed eddy-accumulation system linked to a FTIR spectrometer (Ecotech), a gradient system based on a home-built slower QCL (INRA Orleans) and a fast chamber system. Here we present the results of the study and a detailed examination of the various corrections and errors of the different instruments. Overall, with the exception of the older generation QCL, the average fluxes based on the different fast-response instruments agreed within +/- 7.4%, although fluxes were moderate. The cw-QCL systems showed somewhat better signal-to-noise characteristics and a lower flux detection limit than the ICOS analysers. Intriguingly, there seemed to be some minor differences between the ICOS instruments which showed cross sensitivities to CO to varying degree. Overall the study demonstrates, that, while not cheap, both the ICOS-based instruments and the cw-QCLs are suitable for the measurement of even moderate N2O fluxes.

Emergency response to mass casualty incidents in Lebanon.

PubMed

El Sayed, Mazen J

2013-08-01

The emergency response to mass casualty incidents in Lebanon lacks uniformity. Three recent large-scale incidents have challenged the existing emergency response process and have raised the need to improve and develop incident management for better resilience in times of crisis. We describe some simple emergency management principles that are currently applied in the United States. These principles can be easily adopted by Lebanon and other developing countries to standardize and improve their emergency response systems using existing infrastructure.

1996-1997 TEMA/DOE oversite annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-01-01

The Tennessee Emergency Management Agency (TEMA) has entered into a five-year agreement with the Department of Energy (DOE) to provide emergency response activities associated with the Oak Ridge Reservation (ORR). The Agreement in Principle (AIP) delineates the duties and responsibilities of the parties. The agreement tasked TEMA with the following responsibilities: develop offsite emergency plans; conduct emergency management training; develop offsite emergency organizations; develop emergency communications; develop emergency facilities; conduct exercises and drills; provide detection and protection equipment; and develop an emergency staff. This document reports on progress on these tasks during the past year.

1996--1997 TEMA/DOE oversight annual report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-06-01

The Tennessee Emergency Management Agency (TEMA) has entered into a five-year agreement with the Department of Energy (DOE) to provide emergency response activities associated with the Oak Ridge Reservation (ORR). The Agreement in Principle (AIP) delineates the duties and responsibilities of the parties. The agreement tasked TEMA with the following responsibilities: develop offsite emergency plans; conduct emergency management training; develop offsite emergency organizations; develop emergency communications; develop emergency facilities; conduct exercises and drills; provide detection and protection equipment; and develop an emergency staff. This report describes progress on the 14 deliverables connected with this contract.

The contrasting response of Hadley circulation to different meridional structure of sea surface temperature in CMIP5

NASA Astrophysics Data System (ADS)

Feng, Juan; Li, Jianping; Zhu, Jianlei; Li, Yang; Li, Fei

2018-02-01

The response of the Hadley circulation (HC) to the sea surface temperature (SST) is determined by the meridional structure of SST and varies according to the changing nature of this meridional structure. The capability of the models from the phase 5 of the Coupled Model Intercomparison Project (CMIP5) is utilized to represent the contrast response of the HC to different meridional SST structures. To evaluate the responses, the variations of HC and SST were linearly decomposed into two components: the equatorially asymmetric (HEA for HC, and SEA for SST) and equatorially symmetric (HES for HC, and SES for SST) components. The result shows that the climatological features of HC and tropical SST (including the spatial structures and amplitude) are reasonably simulated in all the models. However, the response contrast of HC to different SST meridional structures shows uncertainties among models. This may be due to the fact that the long-term temporal variabilities of HEA, HES, and SEA are limited reproduced in the models, although the spatial structures of their long-term variabilities are relatively reasonably simulated. These results indicate that the performance of the CMIP5 models to simulate long-term temporal variability of different meridional SST structures and related HC variations plays a fundamental role in the successful reproduction of the response of HC to different meridional SST structures.

Steve Rummel | NREL

Science.gov Websites

Module Intercomparison," Proc. Solar Energies Technologies Review Meeting Nov. 7-10, 2005, NREL tech . Rummel, D.R. Myers, T.L. Stoffel, and D. Waddington, "A Comparison of Photovoltaic Calibration

Czech results at criticality dosimetry intercomparison 2002.

PubMed

Frantisek, Spurný; Jaroslav, Trousil

2004-01-01

Two criticality dosimetry systems were tested by Czech participants during the intercomparison held in Valduc, France, June 2002. The first consisted of the thermoluminescent detectors (TLDs) (Al-P glasses) and Si-diodes as passive neutron dosemeters. Second, it was studied to what extent the individual dosemeters used in the Czech routine personal dosimetry service can give a reliable estimation of criticality accident exposure. It was found that the first system furnishes quite reliable estimation of accidental doses. For routine individual dosimetry system, no important problems were encountered in the case of photon dosemeters (TLDs, film badge). For etched track detectors in contact with the 232Th or 235U-Al alloy, the track density saturation for the spark counting method limits the upper dose at approximately 1 Gy for neutrons with the energy >1 MeV.

Future Directions in Simulating Solar Geoengineering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kravitz, Benjamin S.; Robock, Alan; Boucher, Olivier

2014-08-05

Solar geoengineering is a proposed set of technologies to temporarily alleviate some of the consequences of anthropogenic greenhouse gas emissions. The Geoengineering Model Intercomparison Project (GeoMIP) created a framework of geoengineering simulations in climate models that have been performed by modeling centers throughout the world (B. Kravitz et al., The Geoengineering Model Intercomparison Project (GeoMIP), Atmospheric Science Letters, 12(2), 162-167, doi:10.1002/asl.316, 2011). These experiments use state-of-the-art climate models to simulate solar geoengineering via uniform solar reduction, creation of stratospheric sulfate aerosol layers, or injecting sea spray into the marine boundary layer. GeoMIP has been quite successful in its mission ofmore » revealing robust features and key uncertainties of the modeled effects of solar geoengineering.« less

The Impact of Abrupt Suspension of Solar Radiation Management (Termination Effect) in Experiment G2 of the Geoengineering Model Intercomparison Project (GeoMIP)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Andrew; Haywood, J.; Alterskjaer, Kari

2013-09-11

We have examined changes in climate which result from the sudden termination of geoengineering after 50 years of offsetting a 1% per annum increase in CO2 concentra- tions as simulated by 11 different climate models in experiment G2 of the Geoengineering Model Intercomparison Project. The models agree on a rapid rate of global-mean warming following termination, accompanied by increases in global-mean precipitation rate and in plant net primary productivity, and decreases in sea-ice cover. While there is a considerable degree of consensus for the geographical distribution of warming, there is much less of an agreement regarding the patterns of changemore » in the other quantities.« less

The Cloud Feedback Model Intercomparison Project Observational Simulator Package: Version 2

NASA Astrophysics Data System (ADS)

Swales, Dustin J.; Pincus, Robert; Bodas-Salcedo, Alejandro

2018-01-01

The Cloud Feedback Model Intercomparison Project Observational Simulator Package (COSP) gathers together a collection of observation proxies or satellite simulators that translate model-simulated cloud properties to synthetic observations as would be obtained by a range of satellite observing systems. This paper introduces COSP2, an evolution focusing on more explicit and consistent separation between host model, coupling infrastructure, and individual observing proxies. Revisions also enhance flexibility by allowing for model-specific representation of sub-grid-scale cloudiness, provide greater clarity by clearly separating tasks, support greater use of shared code and data including shared inputs across simulators, and follow more uniform software standards to simplify implementation across a wide range of platforms. The complete package including a testing suite is freely available.

SUMCOR: Cascade summing correction for volumetric sources applying MCNP6.

PubMed

Dias, M S; Semmler, R; Moreira, D S; de Menezes, M O; Barros, L F; Ribeiro, R V; Koskinas, M F

2018-04-01

The main features of code SUMCOR developed for cascade summing correction for volumetric sources are described. MCNP6 is used to track histories starting from individual points inside the volumetric source, for each set of cascade transitions from the radionuclide. Total and FEP efficiencies are calculated for all gamma-rays and X-rays involved in the cascade. Cascade summing correction is based on the matrix formalism developed by Semkow et al. (1990). Results are presented applying the experimental data sent to the participants of two intercomparisons organized by the ICRM-GSWG and coordinated by Dr. Marie-Cristine Lépy from the Laboratoire National Henri Becquerel (LNE-LNHB), CEA, in 2008 and 2010, respectively and compared to the other participants in the intercomparisons. Copyright © 2017 Elsevier Ltd. All rights reserved.

State Emergency Response Commissions

EPA Pesticide Factsheets

The Governor of each state has designated a State Emergency Response Commission (SERC) that is responsible for implementing the Emergency Planning and Community Right-to-Know Act (EPCRA) provisions within its state.

Community response grids: using information technology to help communities respond to bioterror emergencies.

PubMed

Jaeger, Paul T; Fleischmann, Kenneth R; Preece, Jennifer; Shneiderman, Ben; Wu, Philip Fei; Qu, Yan

2007-12-01

Access to accurate and trusted information is vital in preparing for, responding to, and recovering from an emergency. To facilitate response in large-scale emergency situations, Community Response Grids (CRGs) integrate Internet and mobile technologies to enable residents to report information, professional emergency responders to disseminate instructions, and residents to assist one another. CRGs use technology to help residents and professional emergency responders to work together in community response to emergencies, including bioterrorism events. In a time of increased danger from bioterrorist threats, the application of advanced information and communication technologies to community response is vital in confronting such threats. This article describes CRGs, their underlying concepts, development efforts, their relevance to biosecurity and bioterrorism, and future research issues in the use of technology to facilitate community response.

40 CFR Appendix F to Part 112 - Facility-Specific Response Plan

Code of Federal Regulations, 2011 CFR

2011-07-01

... of Contents 1.0Model Facility-Specific Response Plan 1.1Emergency Response Action Plan 1.2Facility.... EC01MR92.015 1.1Emergency Response Action Plan Several sections of the response plan shall be co-located... sections shall be called the Emergency Response Action Plan. The Agency intends that the Action Plan...

49 CFR 172.604 - Emergency response telephone number.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 2 2013-10-01 2013-10-01 false Emergency response telephone number. 172.604... telephone number. (a) A person who offers a hazardous material for transportation must provide an emergency response telephone number, including the area code, for use in an emergency involving the hazardous...

How to Better Prepare Your Community for a Chemical Emergency: A Guide for State, Tribal and Local Agencies

EPA Pesticide Factsheets

This guide provides an overview of EPCRA requirements for State Emergency Response Commissions, Tribal Emergency Response Commissions, Local Emergency Planning Committees, and Tribal Emergency Planning Committees.

Two-Dimensional Intercomparison of Stratospheric Models

NASA Technical Reports Server (NTRS)

Jackman, Charles H. (Editor); Seals, Robert K., Jr. (Editor); Prather, Michael J. (Editor)

1989-01-01

A detailed record is provided for the examination of fundamental differences in photochemistry and transport among atmospheric models. The results of 16 different modeling groups are presented for several model experiments.

40 CFR 1.47 - Office of Solid Waste and Emergency Response.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Office of Solid Waste and Emergency... ORGANIZATION AND GENERAL INFORMATION Headquarters § 1.47 Office of Solid Waste and Emergency Response. The Office of Solid Waste and Emergency Response (OSWER), under the supervision of the Assistant...

40 CFR 1.47 - Office of Solid Waste and Emergency Response.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Office of Solid Waste and Emergency... ORGANIZATION AND GENERAL INFORMATION Headquarters § 1.47 Office of Solid Waste and Emergency Response. The Office of Solid Waste and Emergency Response (OSWER), under the supervision of the Assistant...

49 CFR 172.604 - Emergency response telephone number.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false Emergency response telephone number. 172.604... telephone number. (a) A person who offers a hazardous material for transportation must provide an emergency response telephone number, including the area code, for use in the event of an emergency involving the...

76 FR 78227 - Notice of Request for Extension of Approval of an Information Collection; Emergency Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-16

...] Notice of Request for Extension of Approval of an Information Collection; Emergency Management Response... approval of an information collection associated with the Emergency Management Response System. DATES: We...: For information on the Emergency Management Response System, contact Dr. Steven Finch, Senior Staff...

44 CFR 352.27 - Federal role in the emergency response.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Federal role in the emergency response. 352.27 Section 352.27 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY PREPAREDNESS COMMERCIAL NUCLEAR POWER PLANTS: EMERGENCY PREPAREDNESS PLANNING...

Radiological emergency: Malaysian preparedness and response.

PubMed

Yusof, Mohd Abd Wahab; Ali, Hamrah Mohd

2011-07-01

Planning and preparation in advance for radiological emergencies can help to minimise potential public health and environmental threats if and when an actual emergency occurs. During the planning process, emergency response organisations think through how they would respond to each type of incident and the resources that will be needed. In Malaysia, planning, preparation for and response to radiological emergencies involve many parties. In the event of a radiological emergency and if it is considered a disaster, the National Security Council, the Atomic Energy Licensing Board and the Malaysian Nuclear Agency (Nuclear Malaysia) will work together with other federal agencies, state and local governments, first responders and international organisations to monitor the situation, contain the release, and clean up the contaminated site. Throughout the response, these agencies use their protective action guidelines. This paper discusses Malaysian preparedness for, and response to, any potential radiological emergency.

The new GFDL global atmosphere and land model AM2-LM2: Evaluation with prescribed SST simulations

USGS Publications Warehouse

Anderson, J.L.; Balaji, V.; Broccoli, A.J.; Cooke, W.F.; Delworth, T.L.; Dixon, K.W.; Donner, L.J.; Dunne, K.A.; Freidenreich, S.M.; Garner, S.T.; Gudgel, R.G.; Gordon, C.T.; Held, I.M.; Hemler, R.S.; Horowitz, L.W.; Klein, S.A.; Knutson, T.R.; Kushner, P.J.; Langenhost, A.R.; Lau, N.-C.; Liang, Z.; Malyshev, S.L.; Milly, P.C.D.; Nath, M.J.; Ploshay, J.J.; Ramaswamy, V.; Schwarzkopf, M.D.; Shevliakova, E.; Sirutis, J.J.; Soden, B.J.; Stern, W.F.; Thompson, L.A.; Wilson, R.J.; Wittenberg, A.T.; Wyman, B.L.

2004-01-01

The configuration and performance of a new global atmosphere and land model for climate research developed at the Geophysical Fluid Dynamics Laboratory (GFDL) are presented. The atmosphere model, known as AM2, includes a new gridpoint dynamical core, a prognostic cloud scheme, and a multispecies aerosol climatology, as well as components from previous models used at GFDL. The land model, known as LM2, includes soil sensible and latent heat storage, groundwater storage, and stomatal resistance. The performance of the coupled model AM2-LM2 is evaluated with a series of prescribed sea surface temperature (SST) simulations. Particular focus is given to the model's climatology and the characteristics of interannual variability related to El Nin??o-Southern Oscillation (ENSO). One AM2-LM2 integration was perfor med according to the prescriptions of the second Atmospheric Model Intercomparison Project (AMIP II) and data were submitted to the Program for Climate Model Diagnosis and Intercomparison (PCMDI). Particular strengths of AM2-LM2, as judged by comparison to other models participating in AMIP II, include its circulation and distributions of precipitation. Prominent problems of AM2-LM2 include a cold bias to surface and tropospheric temperatures, weak tropical cyclone activity, and weak tropical intraseasonal activity associated with the Madden-Julian oscillation. An ensemble of 10 AM2-LM 2 integrations with observed SSTs for the second half of the twentieth century permits a statistically reliable assessment of the model's response to ENSO. In general, AM2-LM2 produces a realistic simulation of the anomalies in tropical precipitation and extratropical circulation that are associated with ENSO. ?? 2004 American Meteorological Society.

The AgMIP Wheat Pilot: A multi-model approach for climate change impact assessments.

NASA Astrophysics Data System (ADS)

Asseng, S.

2012-12-01

Asseng S., F. Ewert, C. Rosenzweig, J.W. Jones, J.L. Hatfield, A. Ruane, K.J. Boote, P. Thorburn, R.P. Rötter, D. Cammarano, N. Brisson, B. Basso, P. Martre, D. Ripoche, P. Bertuzzi, P. Steduto, L. Heng, M.A. Semenov, P. Stratonovitch, C. Stockle, G. O'Leary, P.K. Aggarwal, S. Naresh Kumar, C. Izaurralde, J.W. White, L.A. Hunt, R. Grant, K.C. Kersebaum, T. Palosuo, J. Hooker, T. Osborne, J. Wolf, I. Supit, J.E. Olesen, J. Doltra, C. Nendel, S. Gayler, J. Ingwersen, E. Priesack, T. Streck, F. Tao, C. Müller, K. Waha, R. Goldberg, C. Angulo, I. Shcherbak, C. Biernath, D. Wallach, M. Travasso, A. Challinor. Abstract: Crop simulation models have been used to assess the impact of climate change on agriculture. These assessments are often carried out with a single model in a limited number of environments and without determining the uncertainty of simulated impacts. There is a need for a coordinated effort bringing together multiple modeling teams which has been recognized by the Agricultural Model Intercomparison and Improvement Project (AgMIP; www.agmip.org). AgMIP aims to provide more robust estimates of climate impacts on crop yields and agricultural trade, including estimates of associated uncertainties. Here, we present the AgMIP Wheat Pilot Study, the most comprehensive model intercomparison of the response of wheat crops to climate change to date, including 27 wheat models. Crop model uncertainties in assessing climate change impacts are explored and compared with field experimental and Global Circulation Model uncertainties. Causes of impact uncertainties and ways to reduce these are discussed.

Radiative Forcing by Well-Mixed Greenhouse Gases: Estimates from Climate Models in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4)

NASA Technical Reports Server (NTRS)

Collins, W. D.; Ramaswamy, V.; Schwarzkopf, M. D.; Sun, Y.; Portmann, R. W.; Fu, Q.; Casanova, S. E. B.; Dufresne, J.-L.; Fillmore, D. W.; Forster, P. M. D.;

Sensitivity of grounding line dynamics to basal conditions

NASA Astrophysics Data System (ADS)

Gagliardini, O.; Brondex, J.; Chauveau, G.; Gillet-chaulet, F.; Durand, G.

2017-12-01

In the context of a warming climate, the dynamical contribution of Antarctica to future sea level rise is still tainted by high uncertainties. Among the processes entering these uncertainties is the link between basal hydrology, friction and grounding line dynamics. Recent works have shown how sensitive is the response of the grounding line retreat to the choice of the form of the friction law. Indeed, starting from the same initial state, grounding line retreat rates can range over almost two orders of magnitude depending on the friction law formulation.Here, we use a phenomenological law that depends on the water pressure and allows a continuous transition from a Weertman-type friction at low water pressure to a Coulomb-type friction at high water pressure. This friction law depends on two main parameters that control the Weertman and Coulomb regimes. The range of values for these two parameters is only weakly physically constrained, and it can be shown that, for a given basal shear stress, different couples of parameters can conduct to the same sliding velocity. In addition, we show that close to the grounding line where basal water pressure is high, determining these two parameters might conduct to an ill-posed inverse problem with no solution.The aim of this presentation is to discuss a methodology to guide the choice of the two friction parameters and explore the sensitivity of the grounding line dynamics to this initial choice. We present results obtained both on a synthetic configuration used by the Marine Ice Sheet Model Intercomparison exercise and for the Amundsen sea sector using the experiments proposed by InitMIP-Antarctica, the first exercise in a series of ISMIP6 ice-sheet model intercomparison activities.

An Intercomparison of Changes Associated with Earth's Lower Tropospheric Temperature Using Traditional and AMIP-Style Reanalyses

NASA Technical Reports Server (NTRS)

Marquardt-Collow, Allison B.; Bosilovich, Michael G.; Cullather, Richard I.

2017-01-01

Reanalyses have become an integral tool for evaluating regional and global climate variations, and an important component of this is modifications to the energy budget. Reductions in Arctic Sea ice extent has induced an albedo feedback, causing the Arctic to warm more rapidly than anywhere else in the world, referred to as "Arctic Amplification." This has been demonstrated by observations and numerous reanalyses, including the Modern Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2). However, the Arctic Amplification signal is non-existent in a ten member ensemble of the MERRA-2 Atmospheric Model Intercomparison Project (M2AMIP) simulations, using the same prescribed climate forcing, including Sea Surface Temperature (SST) and ice. An evaluation of the temperature tendency within the lower troposphere due to radiation, moisture, and dynamics as well as the surface energy budget in MERRA-2 and M2AMIP will demonstrate that despite identical prescribed SSTs and sea ice in both versions, enhanced warming in the Arctic in MERRA-2 is in response to the analysis increment tendency due to temperature observations. Furthermore, the role of boundary conditions, model biases and changes in observing systems on the Arctic Amplification signal will be assessed. Literature on the topic of Arctic Amplification demonstrates that the enhanced warming begins in the mid-1990s. Anomalously warm Arctic SST in the early time period of MERRA-2 can mute the trend in Arctic lower troposphere temperature without the constraint of observations in M2AMIP. Additionally, MERRA-2 uses three distinct datasets of SST and sea ice concentration, which also plays a role.

Analysis of precipitation teleconnections in CMIP models as a measure of model fidelity in simulating precipitation

NASA Astrophysics Data System (ADS)

Langenbrunner, B.; Neelin, J.; Meyerson, J.

2011-12-01

The accurate representation of precipitation is a recurring issue in global climate models, especially in the tropics. Poor skill in modeling the variability and climate teleconnections associated with El Niño/Southern Oscillation (ENSO) also persisted in the latest Climate Model Intercomparison Project (CMIP) campaigns. Observed ENSO precipitation teleconnections provide a standard by which we can judge a given model's ability to reproduce precipitation and dynamic feedback processes originating in the tropical Pacific. Using CMIP3 Atmospheric Model Intercomparison Project (AMIP) runs as a baseline, we compare precipitation teleconnections between models and observations, and we evaluate these results against available CMIP5 historical and AMIP runs. Using AMIP simulations restricts evaluation to the atmospheric response, as sea surface temperatures (SSTs) in AMIP are prescribed by observations. We use a rank correlation between ENSO SST indices and precipitation to define teleconnections, since this method is robust to outliers and appropriate for non-Gaussian data. Spatial correlations of the modeled and observed teleconnections are then evaluated. We look at these correlations in regions of strong precipitation teleconnections, including equatorial S. America, the "horseshoe" region in the western tropical Pacific, and southern N. America. For each region and season, we create a "normalized projection" of a given model's teleconnection pattern onto that of the observations, a metric that assesses the quality of regional pattern simulations while rewarding signals of correct sign over the region. Comparing this to an area-averaged (i.e., more generous) metric suggests models do better when restrictions on exact spatial dependence are loosened and conservation constraints apply. Model fidelity in regional measures remains far from perfect, suggesting intrinsic issues with the models' regional sensitivities in moist processes.

Field intercomparison of four methane gas analyzers suitable for eddy covariance flux measurements

NASA Astrophysics Data System (ADS)

Peltola, O.; Mammarella, I.; Haapanala, S.; Burba, G.; Vesala, T.

2013-06-01

Performances of four methane gas analyzers suitable for eddy covariance measurements are assessed. The assessment and comparison was performed by analyzing eddy covariance data obtained during summer 2010 (1 April to 26 October) at a pristine fen, Siikaneva, Southern Finland. High methane fluxes with pronounced seasonality have been measured at this fen. The four participating methane gas analyzers are commercially available closed-path units TGA-100A (Campbell Scientific Inc., USA), RMT-200 (Los Gatos Research, USA), G1301-f (Picarro Inc., USA) and an early prototype open-path unit Prototype-7700 (LI-COR Biosciences, USA). The RMT-200 functioned most reliably throughout the measurement campaign, during low and high flux periods. Methane fluxes from RMT-200 and G1301-f had the smallest random errors and the fluxes agree remarkably well throughout the measurement campaign. Cospectra and power spectra calculated from RMT-200 and G1301-f data agree well with corresponding temperature spectra during a high flux period. None of the gas analyzers showed statistically significant diurnal variation for methane flux. Prototype-7700 functioned only for a short period of time, over one month, in the beginning of the measurement campaign during low flux period, and thus, its overall accuracy and season-long performance were not assessed. The open-path gas analyzer is a practical choice for measurement sites in remote locations due to its low power demand, whereas for G1301-f methane measurements interference from water vapor is straightforward to correct since the instrument measures both gases simultaneously. In any case, if only the performance in this intercomparison is considered, RMT-200 performed the best and is the recommended choice if a new fast response methane gas analyzer is needed.

The PMIP4 contribution to CMIP6 - Part 3: The last millennium, scientific objective, and experimental design for the PMIP4 past1000 simulations

NASA Astrophysics Data System (ADS)

Jungclaus, Johann H.; Bard, Edouard; Baroni, Mélanie; Braconnot, Pascale; Cao, Jian; Chini, Louise P.; Egorova, Tania; Evans, Michael; Fidel González-Rouco, J.; Goosse, Hugues; Hurtt, George C.; Joos, Fortunat; Kaplan, Jed O.; Khodri, Myriam; Klein Goldewijk, Kees; Krivova, Natalie; LeGrande, Allegra N.; Lorenz, Stephan J.; Luterbacher, Jürg; Man, Wenmin; Maycock, Amanda C.; Meinshausen, Malte; Moberg, Anders; Muscheler, Raimund; Nehrbass-Ahles, Christoph; Otto-Bliesner, Bette I.; Phipps, Steven J.; Pongratz, Julia; Rozanov, Eugene; Schmidt, Gavin A.; Schmidt, Hauke; Schmutz, Werner; Schurer, Andrew; Shapiro, Alexander I.; Sigl, Michael; Smerdon, Jason E.; Solanki, Sami K.; Timmreck, Claudia; Toohey, Matthew; Usoskin, Ilya G.; Wagner, Sebastian; Wu, Chi-Ju; Leng Yeo, Kok; Zanchettin, Davide; Zhang, Qiong; Zorita, Eduardo

2017-11-01

The pre-industrial millennium is among the periods selected by the Paleoclimate Model Intercomparison Project (PMIP) for experiments contributing to the sixth phase of the Coupled Model Intercomparison Project (CMIP6) and the fourth phase of the PMIP (PMIP4). The past1000 transient simulations serve to investigate the response to (mainly) natural forcing under background conditions not too different from today, and to discriminate between forced and internally generated variability on interannual to centennial timescales. This paper describes the motivation and the experimental set-ups for the PMIP4-CMIP6 past1000 simulations, and discusses the forcing agents orbital, solar, volcanic, and land use/land cover changes, and variations in greenhouse gas concentrations. The past1000 simulations covering the pre-industrial millennium from 850 Common Era (CE) to 1849 CE have to be complemented by historical simulations (1850 to 2014 CE) following the CMIP6 protocol. The external forcings for the past1000 experiments have been adapted to provide a seamless transition across these time periods. Protocols for the past1000 simulations have been divided into three tiers. A default forcing data set has been defined for the Tier 1 (the CMIP6 past1000) experiment. However, the PMIP community has maintained the flexibility to conduct coordinated sensitivity experiments to explore uncertainty in forcing reconstructions as well as parameter uncertainty in dedicated Tier 2 simulations. Additional experiments (Tier 3) are defined to foster collaborative model experiments focusing on the early instrumental period and to extend the temporal range and the scope of the simulations. This paper outlines current and future research foci and common analyses for collaborative work between the PMIP and the observational communities (reconstructions, instrumental data).

Emergency material allocation with time-varying supply-demand based on dynamic optimization method for river chemical spills.

PubMed

Liu, Jie; Guo, Liang; Jiang, Jiping; Jiang, Dexun; Wang, Peng

2018-04-13

Aiming to minimize the damage caused by river chemical spills, efficient emergency material allocation is critical for an actual emergency rescue decision-making in a quick response. In this study, an emergency material allocation framework based on time-varying supply-demand constraint is developed to allocate emergency material, minimize the emergency response time, and satisfy the dynamic emergency material requirements in post-accident phases dealing with river chemical spills. In this study, the theoretically critical emergency response time is firstly obtained for the emergency material allocation system to select a series of appropriate emergency material warehouses as potential supportive centers. Then, an enumeration method is applied to identify the practically critical emergency response time, the optimum emergency material allocation and replenishment scheme. Finally, the developed framework is applied to a computational experiment based on south-to-north water transfer project in China. The results illustrate that the proposed methodology is a simple and flexible tool for appropriately allocating emergency material to satisfy time-dynamic demands during emergency decision-making. Therefore, the decision-makers can identify an appropriate emergency material allocation scheme in a balance between time-effective and cost-effective objectives under the different emergency pollution conditions.

[Emergency response management near the tracks of the public railway network: special aspects of missions connected with the German national railway system].

PubMed

Krämer, P; Aul, A; Vock, B; Frank, C

2010-11-01

Emergency response management and rescue operations concerning the railway network in Germany need special attention and implementation in several ways. The emergency response concerning the German national railway network managed by Deutsche Bahn AG is subject to various rules and regulations which have to be followed precisely. Only by following these rules and procedures is the safety of all emergency staff at the scene ensured. The German national railway network (Deutsche Bahn AG) provides its own emergency response control center, which specializes in managing its response to emergencies and dispatches an emergency response manager to the scene. This person serves as the primary Deutsche Bahn AG representative at the scene and is the only person who is allowed to earth the railway electrical power lines. This article will discuss different emergency situations concerning railway accidents and the emergency medical response to them based on a near collision with a high speed train during a rescue mission close to the railway track. Injury to personnel could only be avoided by chance and luck. The dangers and risks for rescue staff are specified. Furthermore, the article details practical guidelines for rescue operations around the German national railway track system.

Inter-comparison of source apportionment of PM10 using PMF and CMB in three sites nearby an industrial area in central Italy

NASA Astrophysics Data System (ADS)

Cesari, Daniela; Donateo, Antonio; Conte, Marianna; Contini, Daniele

2016-12-01

Receptor models (RMs), based on chemical composition of particulate matter (PM), such as Chemical Mass Balance (CMB) and Positive Matrix Factorization (PMF), represent useful tools for determining the impact of PM sources to air quality. This information is useful, especially in areas influenced by anthropogenic activities, to plan mitigation strategies for environmental management. Recent inter-comparison of source apportionment (SA) results showed that one of the difficulties in the comparison of estimated source contributions is the compatibility of the sources, i.e. the chemical profiles of factor/sources used in receptor models. This suggests that SA based on integration of several RMs could give more stable and reliable solutions with respect to a single model. The aim of this work was to perform inter-comparison of PMF (using PMF3.0 and PMF5.0 codes) and CMB outputs, focusing on both source chemical profiles and estimates of source contributions. The dataset included 347 daily PM10 samples collected in three sites in central Italy located near industrial emissions. Samples were chemically analysed for the concentrations of 21 chemical species (NH4+, Ca2 +, Mg2 +, Na+, K+, Mg2 +, SO42 -, NO3-, Cl-, Si, Al, Ti, V, Mn, Fe, Ni, Cu, Zn, Br, EC, and OC) used as input of RMs. The approach identified 9 factor/sources: marine, traffic, resuspended dust, biomass burning, secondary sulphate, secondary nitrate, crustal, coal combustion power plant and harbour-industrial. Results showed that the application of constraints in PMF5.0 improved interpretability of profiles and comparability of estimated source contributions with stoichiometric calculations. The inter-comparison of PMF and CMB gave significant differences for secondary nitrate, biomass burning, and harbour-industrial sources, due to non-compatibility of these source profiles that have local specificities. When these site-dependent specificities were taken into account, optimising the input source profiles of CMB, a significant improvement in the comparison of the estimated source contributions with PMF was obtained.

Biogeochemical Protocols and Diagnostics for the CMIP6 Ocean Model Intercomparison Project (OMIP)

NASA Technical Reports Server (NTRS)

Orr, James C.; Najjar, Raymond G.; Aumont, Olivier; Bopp, Laurent; Bullister, John L.; Danabasoglu, Gokhan; Doney, Scott C.; Dunne, John P.; Dutay, Jean-Claude; Graven, Heather;

Compatibility of different measurement techniques of global solar radiation and application for long-term observations at Izaña Observatory

NASA Astrophysics Data System (ADS)

Delia García, Rosa; Cuevas, Emilio; García, Omaira Elena; Ramos, Ramón; Romero-Campos, Pedro Miguel; de Ory, Fernado; Cachorro, Victoria Eugenia; de Frutos, Angel

2017-03-01

A 1-year inter-comparison of classical and modern radiation and sunshine duration (SD) instruments has been performed at Izaña Atmospheric Observatory (IZO) located in Tenerife (Canary Islands, Spain) starting on 17 July 2014. We compare daily global solar radiation (GSRH) records measured with a Kipp & Zonen CM-21 pyranometer, taken in the framework of the Baseline Surface Radiation Network, with those measured with a multifilter rotating shadowband radiometer (MFRSR), a bimetallic pyranometer (PYR) and GSRH estimated from sunshine duration performed by a Campbell-Stokes sunshine recorder (CS) and a Kipp & Zonen sunshine duration sensor (CSD). Given that the BSRN GSRH records passed strict quality controls (based on principles of physical limits and comparison with the LibRadtran model), they have been used as reference in the inter-comparison study. We obtain an overall root mean square error (RMSE) of ˜ 0.9 MJm-2 (4 %) for PYR and MFRSR GSRH, 1.9 (7 %) and 1.2 MJm-2 (5 %) for CS and CSD GSRH, respectively. Factors such as temperature, relative humidity (RH) and the solar zenith angle (SZA) have been shown to moderately affect the GSRH observations. As an application of the methodology developed in this work, we have re-evaluated the GSRH data time series obtained at IZO with two PYRs between 1977 and 1991. Their high consistency and temporal stability have been proved by comparing with GSRH estimates obtained from SD observations. These results demonstrate that (1) the continuous-basis inter-comparison of different GSRH techniques offers important diagnostics for identifying inconsistencies between GSRH data records, and (2) the GSRH measurements performed with classical and more simple instruments are consistent with more modern techniques and, thus, valid to recover GSRH data time series and complete worldwide distributed GSRH data. The inter-comparison and quality assessment of these different techniques have allowed us to obtain a complete and consistent long-term global solar radiation series (1977-2015) at Izaña.

Inter-comparison of three-dimensional models of volcanic plumes

USGS Publications Warehouse

Suzuki, Yujiro; Costa, Antonio; Cerminara, Matteo; Esposti Ongaro, Tomaso; Herzog, Michael; Van Eaton, Alexa; Denby, Leif

2016-01-01

We performed an inter-comparison study of three-dimensional models of volcanic plumes. A set of common volcanological input parameters and meteorological conditions were provided for two kinds of eruptions, representing a weak and a strong eruption column. From the different models, we compared the maximum plume height, neutral buoyancy level (where plume density equals that of the atmosphere), and level of maximum radial spreading of the umbrella cloud. We also compared the vertical profiles of eruption column properties, integrated across cross-sections of the plume (integral variables). Although the models use different numerical procedures and treatments of subgrid turbulence and particle dynamics, the inter-comparison shows qualitatively consistent results. In the weak plume case (mass eruption rate 1.5 × 106 kg s− 1), the vertical profiles of plume properties (e.g., vertical velocity, temperature) are similar among models, especially in the buoyant plume region. Variability among the simulated maximum heights is ~ 20%, whereas neutral buoyancy level and level of maximum radial spreading vary by ~ 10%. Time-averaging of the three-dimensional (3D) flow fields indicates an effective entrainment coefficient around 0.1 in the buoyant plume region, with much lower values in the jet region, which is consistent with findings of small-scale laboratory experiments. On the other hand, the strong plume case (mass eruption rate 1.5 × 109 kg s− 1) shows greater variability in the vertical plume profiles predicted by the different models. Our analysis suggests that the unstable flow dynamics in the strong plume enhances differences in the formulation and numerical solution of the models. This is especially evident in the overshooting top of the plume, which extends a significant portion (~ 1/8) of the maximum plume height. Nonetheless, overall variability in the spreading level and neutral buoyancy level is ~ 20%, whereas that of maximum height is ~ 10%. This inter-comparison study has highlighted the different capabilities of 3D volcanic plume models, and identified key features of weak and strong plumes, including the roles of jet stability, entrainment efficiency, and particle non-equilibrium, which deserve future investigation in field, laboratory, and numerical studies.

Biogeochemical protocols and diagnostics for the CMIP6 Ocean Model Intercomparison Project (OMIP)

NASA Astrophysics Data System (ADS)

Orr, James C.; Najjar, Raymond G.; Aumont, Olivier; Bopp, Laurent; Bullister, John L.; Danabasoglu, Gokhan; Doney, Scott C.; Dunne, John P.; Dutay, Jean-Claude; Graven, Heather; Griffies, Stephen M.; John, Jasmin G.; Joos, Fortunat; Levin, Ingeborg; Lindsay, Keith; Matear, Richard J.; McKinley, Galen A.; Mouchet, Anne; Oschlies, Andreas; Romanou, Anastasia; Schlitzer, Reiner; Tagliabue, Alessandro; Tanhua, Toste; Yool, Andrew

2017-06-01

The Ocean Model Intercomparison Project (OMIP) focuses on the physics and biogeochemistry of the ocean component of Earth system models participating in the sixth phase of the Coupled Model Intercomparison Project (CMIP6). OMIP aims to provide standard protocols and diagnostics for ocean models, while offering a forum to promote their common assessment and improvement. It also offers to compare solutions of the same ocean models when forced with reanalysis data (OMIP simulations) vs. when integrated within fully coupled Earth system models (CMIP6). Here we detail simulation protocols and diagnostics for OMIP's biogeochemical and inert chemical tracers. These passive-tracer simulations will be coupled to ocean circulation models, initialized with observational data or output from a model spin-up, and forced by repeating the 1948-2009 surface fluxes of heat, fresh water, and momentum. These so-called OMIP-BGC simulations include three inert chemical tracers (CFC-11, CFC-12, SF6) and biogeochemical tracers (e.g., dissolved inorganic carbon, carbon isotopes, alkalinity, nutrients, and oxygen). Modelers will use their preferred prognostic BGC model but should follow common guidelines for gas exchange and carbonate chemistry. Simulations include both natural and total carbon tracers. The required forced simulation (omip1) will be initialized with gridded observational climatologies. An optional forced simulation (omip1-spunup) will be initialized instead with BGC fields from a long model spin-up, preferably for 2000 years or more, and forced by repeating the same 62-year meteorological forcing. That optional run will also include abiotic tracers of total dissolved inorganic carbon and radiocarbon, CTabio and 14CTabio, to assess deep-ocean ventilation and distinguish the role of physics vs. biology. These simulations will be forced by observed atmospheric histories of the three inert gases and CO2 as well as carbon isotope ratios of CO2. OMIP-BGC simulation protocols are founded on those from previous phases of the Ocean Carbon-Cycle Model Intercomparison Project. They have been merged and updated to reflect improvements concerning gas exchange, carbonate chemistry, and new data for initial conditions and atmospheric gas histories. Code is provided to facilitate their implementation.

Revisiting the PLUMBER Experiments from a Process-Diagnostics Perspective

NASA Astrophysics Data System (ADS)

Nearing, G. S.; Ruddell, B. L.; Clark, M. P.; Nijssen, B.; Peters-Lidard, C. D.

2017-12-01

The PLUMBER benchmarking experiments [1] showed that some of the most sophisticated land models (CABLE, CH-TESSEL, COLA-SSiB, ISBA-SURFEX, JULES, Mosaic, Noah, ORCHIDEE) were outperformed - in simulations of half-hourly surface energy fluxes - by instantaneous, out-of-sample, and globally-stationary regressions with no state memory. One criticism of PLUMBER is that the benchmarking methodology was not derived formally, so that applying a similar methodology with different performance metrics can result in qualitatively different results. Another common criticism of model intercomparison projects in general is that they offer little insight into process-level deficiencies in the models, and therefore are of marginal value for helping to improve the models. We address both of these issues by proposing a formal benchmarking methodology that also yields a formal and quantitative method for process-level diagnostics. We apply this to the PLUMBER experiments to show that (1) the PLUMBER conclusions were generally correct - the models use only a fraction of the information available to them from met forcing data (<50% by our analysis), and (2) all of the land models investigated by PLUMBER have similar process-level error structures, and therefore together do not represent a meaningful sample of structural or epistemic uncertainty. We conclude by suggesting two ways to improve the experimental design of model intercomparison and/or model benchmarking studies like PLUMBER. First, PLUMBER did not report model parameter values, and it is necessary to know these values to separate parameter uncertainty from structural uncertainty. This is a first order requirement if we want to use intercomparison studies to provide feedback to model development. Second, technical documentation of land models is inadequate. Future model intercomparison projects should begin with a collaborative effort by model developers to document specific differences between model structures. This could be done in a reproducible way using a unified, process-flexible system like SUMMA [2]. [1] Best, M.J. et al. (2015) 'The plumbing of land surface models: benchmarking model performance', J. Hydrometeor. [2] Clark, M.P. et al. (2015) 'A unified approach for process-based hydrologic modeling: 1. Modeling concept', Water Resour. Res.

GEO-LEO reflectance band inter-comparison with BRDF and atmospheric scattering corrections

NASA Astrophysics Data System (ADS)

Chang, Tiejun; Xiong, Xiaoxiong Jack; Keller, Graziela; Wu, Xiangqian

2017-09-01

The inter-comparison of the reflective solar bands between the instruments onboard a geostationary orbit satellite and onboard a low Earth orbit satellite is very helpful to assess their calibration consistency. GOES-R was launched on November 19, 2016 and Himawari 8 was launched October 7, 2014. Unlike the previous GOES instruments, the Advanced Baseline Imager on GOES-16 (GOES-R became GOES-16 after November 29 when it reached orbit) and the Advanced Himawari Imager (AHI) on Himawari 8 have onboard calibrators for the reflective solar bands. The assessment of calibration is important for their product quality enhancement. MODIS and VIIRS, with their stringent calibration requirements and excellent on-orbit calibration performance, provide good references. The simultaneous nadir overpass (SNO) and ray-matching are widely used inter-comparison methods for reflective solar bands. In this work, the inter-comparisons are performed over a pseudo-invariant target. The use of stable and uniform calibration sites provides comparison with appropriate reflectance level, accurate adjustment for band spectral coverage difference, reduction of impact from pixel mismatching, and consistency of BRDF and atmospheric correction. The site in this work is a desert site in Australia (latitude -29.0 South; longitude 139.8 East). Due to the difference in solar and view angles, two corrections are applied to have comparable measurements. The first is the atmospheric scattering correction. The satellite sensor measurements are top of atmosphere reflectance. The scattering, especially Rayleigh scattering, should be removed allowing the ground reflectance to be derived. Secondly, the angle differences magnify the BRDF effect. The ground reflectance should be corrected to have comparable measurements. The atmospheric correction is performed using a vector version of the Second Simulation of a Satellite Signal in the Solar Spectrum modeling and BRDF correction is performed using a semi-empirical model. AHI band 1 (0.47μm) shows good matching with VIIRS band M3 with difference of 0.15%. AHI band 5 (1.69μm) shows largest difference in comparison with VIIRS M10.

Characterizing a Quantum Cascade Tunable Infrared Laser Differential Absorption Spectrometer (QC-TILDAS) for Measurements of Atmospheric Ammonia

NASA Astrophysics Data System (ADS)

Ellis, R.; Murphy, J. G.; van Haarlem, R.; Pattey, E.; O'Brien, J.

2009-05-01

A compact, fast response Quantum Cascade Tunable Infrared Laser Differential Absorption Spectrometer (QC- TILDAS) for measurements of ammonia has been evaluated under both laboratory and field conditions. Absorption of radiation from a pulsed, thermoelectrically cooled QC laser occurs at reduced pressure in a 76 m path length, 0.5 L volume multiple pass absorption cell. Detection is achieved using a thermoelectrically cooled HgCdTe infrared detector. A novel sampling technique was used, consisting of a short, heated, quartz inlet with a hydrophobic coating to minimize the adsorption of ammonia to surfaces. The inlet contains a critical orifice that reduces the pressure, a virtual impactor for separation of particles and additional ports for delivering ammonia free background air and calibration gas standards. This instrument has been found to have a detection limit of 0.3 ppb with a time resolution of 1 s. The sampling technique has been compared to the results of a conventional lead salt Tunable Diode Laser (TDL) absorption spectrometer during a laboratory intercomparison. Various lengths and types of sample inlet tubing material, heated and unheated, under dry and ambient humidity conditions with ammonia concentrations ranging from 10-1000 ppb were investigated. Preliminary analysis suggests the time response improves with the use of short, PFA tubing sampling lines. No significant improvement was observed when using a heated sampling line and humidity was seen to play an important role on the bi-exponential decay of ammonia. A field intercomparison of the QC-TILDAS with a modified Thermo 42C chemiluminescence based analyzer was also performed at Environment Canada's Centre for Atmospheric Research Experiments (CARE) in the rural town of Egbert, ON between May-July 2008. Background tests and calibrations using two different permeation tube sources and an ammonia gas cylinder were regularly carried out throughout the study. Results indicate a very good correlation (r2>0.9) between the two instruments at the beginning of the study, when regular background subtraction was applied to the QC- TILDAS.

An Adaptation Dilemma Caused by Impacts-Modeling Uncertainty

NASA Astrophysics Data System (ADS)

Frieler, K.; Müller, C.; Elliott, J. W.; Heinke, J.; Arneth, A.; Bierkens, M. F.; Ciais, P.; Clark, D. H.; Deryng, D.; Doll, P. M.; Falloon, P.; Fekete, B. M.; Folberth, C.; Friend, A. D.; Gosling, S. N.; Haddeland, I.; Khabarov, N.; Lomas, M. R.; Masaki, Y.; Nishina, K.; Neumann, K.; Oki, T.; Pavlick, R.; Ruane, A. C.; Schmid, E.; Schmitz, C.; Stacke, T.; Stehfest, E.; Tang, Q.; Wisser, D.

2013-12-01

Ensuring future well-being for a growing population under either strong climate change or an aggressive mitigation strategy requires a subtle balance of potentially conflicting response measures. In the case of competing goals, uncertainty in impact estimates plays a central role when high confidence in achieving a primary objective (such as food security) directly implies an increased probability of uncertainty induced failure with regard to a competing target (such as climate protection). We use cross sectoral consistent multi-impact model simulations from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP, www.isi-mip.org) to illustrate this uncertainty dilemma: RCP projections from 7 global crop, 11 hydrological, and 7 biomes models are combined to analyze irrigation and land use changes as possible responses to climate change and increasing crop demand due to population growth and economic development. We show that - while a no-regrets option with regard to climate protection - additional irrigation alone is not expected to balance the demand increase by 2050. In contrast, a strong expansion of cultivated land closes the projected production-demand gap in some crop models. However, it comes at the expense of a loss of natural carbon sinks of order 50%. Given the large uncertainty of state of the art crop model projections even these strong land use changes would not bring us ';on the safe side' with respect to food supply. In a world where increasing carbon emissions continue to shrink the overall solution space, we demonstrate that current impacts-modeling uncertainty is a luxury we cannot afford. ISI-MIP is intended to provide cross sectoral consistent impact projections for model intercomparison and improvement as well as cross-sectoral integration. The results presented here were generated within the first Fast-Track phase of the project covering global impact projections. The second phase will also include regional projections. It is the aim of the project to build up a CMIP like open archive for climate impact projections allowing for the necessary sharpening the our picture of a 1,2,3,4 degrees warmer world.

Analysis of 85Kr: a comparison at the 10-14 level using micro-liter samples

PubMed Central

Yang, G. -M.; Cheng, C. -F.; Jiang, W.; Lu, Z. -T.; Purtschert, R.; Sun, Y. -R.; Tu, L. -Y.; Hu, S. -M.

2013-01-01

The isotopic abundance of 85Kr in the atmosphere, currently at the level of 10−11, has increased by orders of magnitude since the dawn of nuclear age. With a half-life of 10.76 years, 85Kr is of great interest as tracers for environmental samples such as air, groundwater and ice. Atom Trap Trace Analysis (ATTA) is an emerging method for the analysis of rare krypton isotopes at isotopic abundance levels as low as 10−14 using krypton gas samples of a few micro-liters. Both the reliability and reproducibility of the method are examined in the present study by an inter-comparison among different instruments. The 85Kr/Kr ratios of 12 samples, in the range of 10−13 to 10−10, are measured independently in three laboratories: a low-level counting laboratory in Bern, Switzerland, and two ATTA laboratories, one in Hefei, China, and another in Argonne, USA. The results are in agreement at the precision level of 5%. PMID:23549244

TEMORA 1: A new zircon standard for Phanerozoic U-Pb geochronology

USGS Publications Warehouse

Black, L.P.; Kamo, S.L.; Allen, C.M.; Aleinikoff, J.N.; Davis, D.W.; Korsch, R.J.; Foudoulis, C.

2003-01-01

The role of the standard is critical to the derivation of reliable U-Pb zircon ages by micro-beam analysis. For maximum reliability, it is critically important that the utilised standard be homogeneous at all scales of analysis. It is equally important that the standard has been precisely and accurately dated by an independent technique. This study reports the emergence of a new zircon standard that meets those criteria, as demonstrated by Sensitive High Resolution Ion MicroProbe (SHRIMP), isotope dilution thermal ionisation mass-spectrometry (IDTIMS) and excimer laser ablation- inductively coupled plasma-mass-spectrometry (ELA-ICP-MS) documentation. The TEMORA 1 zircon standard derives from the Middledale Gabbroic Diorite, a high-level mafic stock within the Palaeozoic Lachlan Orogen of eastern Australia. Its 206Pb/238U IDTIMS age has been determined to be 416.75??0.24 Ma (95% confidence limits), based on measurement errors alone. Spike-calibration uncertainty limits the accuracy to 416.8??1.1 Ma for U-Pb intercomparisons between different laboratories that do not use a common spike. ?? 2003 Published by Elsevier Science B.V. All rights reserved.

Intercomparison of magnetic field measurements near MV/LV transformer substations: methodological planning and results.

PubMed

Violanti, S; Fraschetta, M; Adda, S; Caputo, E

2009-12-01

Within the framework of Environmental Agencies system's activities, coordinated by ISPRA (superior institute for environmental protection and research), a comparison among measurements was designed and accomplished, in order to go into depth on the matter of measurement problems and to evaluate magnetic field at power frequencies. These measurements have been taken near medium voltage /low voltage transformer substation. This project was developed with the contribution of several experts who belong to different Regional Agencies. In three of these regions, substations having specific international standard characteristics were chosen; then a measurement and data analysis protocol was arranged. Data analysis showed a good level of coherence among results obtained by different laboratories. However, a range of problems emerged, either during the protocol predisposition and definition of the data analysis procedure or during the execution of measures and data reprocessing, because of the spatial and temporal variability of magnetic field. These problems represent elements of particular interest in determining a correct measurement methodology, whose purpose is the comparison with limits of exposure, attention values and quality targets.

Plant ecosystem responses to rising atmospheric CO2: applying a "two-timing" approach to assess alternative hypotheses for mechanisms of nutrient limitation

NASA Astrophysics Data System (ADS)

Medlyn, B.; Jiang, M.; Zaehle, S.

2017-12-01

There is now ample experimental evidence that the response of terrestrial vegetation to rising atmospheric CO2 concentration is modified by soil nutrient availability. How to represent nutrient cycling processes is thus a key consideration for vegetation models. We have previously used model intercomparison to demonstrate that models incorporating different assumptions predict very different responses at Free-Air CO2 Enrichment experiments. Careful examination of model outputs has provided some insight into the reasons for the different model outcomes, but it is difficult to attribute outcomes to specific assumptions. Here we investigate the impact of individual assumptions in a generic plant carbon-nutrient cycling model. The G'DAY (Generic Decomposition And Yield) model is modified to incorporate alternative hypotheses for nutrient cycling. We analyse the impact of these assumptions in the model using a simple analytical approach known as "two-timing". This analysis identifies the quasi-equilibrium behaviour of the model at the time scales of the component pools. The analysis provides a useful mathematical framework for probing model behaviour and identifying the most critical assumptions for experimental study.

The knowledge, attitude and behavior about public health emergencies and the response capacity of primary care medical staffs of Guangdong Province, China.

PubMed

Zhiheng, Zhou; Caixia, Wang; Jiaji, Wang; Huajie, Yang; Chao, Wang; Wannian, Liang

2012-09-25

Primary care medical staffs' knowledge, attitude and behavior about health emergency and the response capacity are directly related to the control and prevention of public health emergencies. Therefore, it is of great significance for improving primary care to gain in-depth knowledge about knowledge, attitude and behavior and the response capacity of primary care medical staffs. The main objective of this study is to explore knowledge, attitude and behavior, and the response capacity of primary care medical staffs of Guangdong Province, China. Stratified clustered sample method was used in the anonymous questionnaire investigation about knowledge, attitude and behavior, and the response capacity of 3410 primary care medical staffs in 15 cities of Guangdong Province, China from July, 2010 to October 2010. The emergency response capacity was evaluated by 33 questions. The highest score of the response capacity was 100 points (full score), score of 70 was a standard. 62.4% primary care medical staffs believed that public health emergencies would happen. Influenza (3.86 ± 0.88), food poisoning (3.35 ± 0.75), and environmental pollution events (3.23 ± 0.80) (the total score was 5) were considered most likely to occur. Among the 7 public health emergency skills, the highest self-assessment score is "public health emergency prevention skills" (2.90 ± 0.68), the lowest is "public health emergency risk management (the total score was 5)" (1.81 ± 0.40). Attitude evaluation showed 66.1% of the medical staffs believed that the community awareness of risk management were ordinary. Evaluation of response capacity of health emergency showed that the score of primary care medical staffs was 67.23 ± 10.61, and the response capacity of senior physicians, public health physicians and physicians with relatively long-term practice were significantly better (P <0.05). Multiple linear stepwise regression analysis showed gender, title, position, type of work, work experience and whether to participate relative training were the main factors affecting the health emergency response capacity. The knowledge, attitude and behavior about public health emergencies and the response capacity of primary care medical staffs of Guangdong Province (China) were poor. Health administrative departments should strengthen the training of health emergency knowledge and skills of the primary care medical staffs to enhance their health emergency response capabilities.

49 CFR 1.44 - Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 1 2013-10-01 2013-10-01 false Office of Intelligence, Security and Emergency... DELEGATION OF POWERS AND DUTIES Office of the Secretary Ost Officials § 1.44 Office of Intelligence, Security and Emergency Response. The Director of the Office of Intelligence, Security and Emergency Response is...

49 CFR 1.44 - Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 1 2014-10-01 2014-10-01 false Office of Intelligence, Security and Emergency... DELEGATION OF POWERS AND DUTIES Office of the Secretary Ost Officials § 1.44 Office of Intelligence, Security and Emergency Response. The Director of the Office of Intelligence, Security and Emergency Response is...

49 CFR 1.44 - Office of Intelligence, Security and Emergency Response.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 1 2012-10-01 2012-10-01 false Office of Intelligence, Security and Emergency... DELEGATION OF POWERS AND DUTIES Office of the Secretary Ost Officials § 1.44 Office of Intelligence, Security and Emergency Response. The Director of the Office of Intelligence, Security and Emergency Response is...

CDC's Evolving Approach to Emergency Response.

PubMed

Redd, Stephen C; Frieden, Thomas R

The Centers for Disease Control and Prevention (CDC) transformed its approach to preparing for and responding to public health emergencies following the anthrax attacks of 2001. The Office of Public Health Preparedness and Response, an organizational home for emergency response at CDC, was established, and 4 programs were created or greatly expanded after the anthrax attacks: (1) an emergency management program, including an Emergency Operations Center; (2) increased support of state and local health department efforts to prepare for emergencies; (3) a greatly enlarged Strategic National Stockpile of medicines, vaccines, and medical equipment; and (4) a regulatory program to assure that work done on the most dangerous pathogens and toxins is done as safely and securely as possible. Following these changes, CDC led responses to 3 major public health emergencies: the 2009-10 H1N1 influenza pandemic, the 2014-16 Ebola epidemic in West Africa, and the ongoing Zika epidemic. This article reviews the programs of CDC's Office of Public Health Preparedness, the major responses, and how these responses have resulted in changes in CDC's approach to responding to public health emergencies.

From SARS to H7N9: the mechanism of responding to emerging communicable diseases has made great progress in China.

PubMed

Yao, Linong; Chen, Enfu; Chen, Zhiping; Gong, Zhenyu

2013-12-01

The outbreak of severe acute respiratory syndrome (SARS) in 2003 indicated that China's existing former mechanism for emergency management was very vulnerable. The Chinese Government has since established a new mechanism for responding to emerging communicable diseases. This paper examined the current status of and developments in China's response to emerging communicable diseases from the outbreak of SARS in 2003 to the outbreak of H7N9 virus infection in 2013. Results indicated that the current mechanism for emergency responses to emerging communicable diseases in China has made great achievements in terms of command and decision-making, organization and collaboration, monitoring and early warning systems, protection, and international communication and cooperation. This mechanism for responding to emerging communicable diseases allowed China to successfully deal with outbreaks of the H5N1 bird flu, H1N1 flu, and H7N9 bird flu. However, a better coordination system, a more complete Office of Responses to Public Health Emergencies, administrative responsibility and error correction, better personnel training, and government responsibility may help to improve the response to emerging communicable diseases. Such improvements are eagerly anticipated.

49 CFR 172.600 - Applicability and general requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, TRAINING REQUIREMENTS, AND SECURITY PLANS Emergency Response Information § 172.600 Applicability and... prescribes requirements for providing and maintaining emergency response information during transportation...

49 CFR 172.600 - Applicability and general requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... MATERIALS TABLE, SPECIAL PROVISIONS, HAZARDOUS MATERIALS COMMUNICATIONS, EMERGENCY RESPONSE INFORMATION, TRAINING REQUIREMENTS, AND SECURITY PLANS Emergency Response Information § 172.600 Applicability and... prescribes requirements for providing and maintaining emergency response information during transportation...

Development of urban planning guidelines for improving emergency response capacities in seismic areas of Iran.

PubMed

Hosseini, Kambod Amini; Jafari, Mohammad Kazem; Hosseini, Maziar; Mansouri, Babak; Hosseinioon, Solmaz

2009-10-01

This paper presents the results of research carried out to improve emergency response activities in earthquake-prone areas of Iran. The research concentrated on emergency response operations, emergency medical care, emergency transportation, and evacuation-the most important issues after an earthquake with regard to saving the lives of victims. For each topic, some guidelines and criteria are presented for enhancing emergency response activities, based on evaluations of experience of strong earthquakes that have occurred over the past two decades in Iran, notably Manjil (1990), Bam (2003), Firouz Abad-Kojour (2004), Zarand (2005) and Broujerd (2006). These guidelines and criteria are applicable to other national contexts, especially countries with similar seismic and social conditions as Iran. The results of this study should be incorporated into comprehensive plans to ensure sustainable development or reconstruction of cities as well as to augment the efficiency of emergency response after an earthquake.

Lessons Learned from Emergency Response Vaccination Efforts for Cholera, Typhoid, Yellow Fever, and Ebola

PubMed Central

Date, Kashmira A.; Sreenivasan, Nandini; Harris, Jennifer B.; Hyde, Terri B.

2017-01-01

Countries must be prepared to respond to public health threats associated with emergencies, such as natural disasters, sociopolitical conflicts, or uncontrolled disease outbreaks. Rapid vaccination of populations vulnerable to epidemic-prone vaccine-preventable diseases is a major component of emergency response. Emergency vaccination planning presents challenges, including how to predict resource needs, expand vaccine availability during global shortages, and address regulatory barriers to deliver new products. The US Centers for Disease Control and Prevention supports countries to plan, implement, and evaluate emergency vaccination response. We describe work of the Centers for Disease Control and Prevention in collaboration with global partners to support emergency vaccination against cholera, typhoid, yellow fever, and Ebola, diseases for which a new vaccine or vaccine formulation has played a major role in response. Lessons learned will help countries prepare for future emergencies. Integration of vaccination with emergency response augments global health security through reducing disease burden, saving lives, and preventing spread across international borders. PMID:29155670

Constraints on long-term carbon-climate feedbacks from spatially resolved CO2 growth rate fluctuations linked to temperature and precipitation

NASA Astrophysics Data System (ADS)

Keppel-Aleks, G.; Hoffman, F. M.

2014-12-01

Feedbacks between the global carbon cycle and climate represent one of the largest uncertainties in climate prediction. A promising method for reducing uncertainty in predictions of carbon-climate feedbacks is based on identifying an "emergent constraint" that leverages correlations between mechanistically linked long-term feedbacks and short-term variations within the model ensemble. By applying contemporary observations to evaluate model skill in simulating short-term variations, we may be able to better assess the probability of simulated long-term feedbacks. We probed the constraint on long-term terrestrial carbon stocks provided by climate-driven fluctuations in the atmospheric CO2 growth rate at contemporary timescales. We considered the impact of both temperature and precipitation anomalies on terrestrial ecosystem exchange and further separated the direct influence of fire where possible. When we explicitly considered the role of atmospheric transport in smoothing the imprint of climate-driven flux anomalies on atmospheric CO2 patterns, we found that the extent of temporal averaging of both the observations and ESM output leads to estimates for the long-term climate sensitivity of tropical land carbon storage that are different by a factor of two. In the context of these results, we discuss strategies for applying emergent constraints for benchmarking biogeochemical feedbacks in ESMs. Specifically, our results underscore the importance of selecting appropriate observational benchmarks and, for future model intercomparison projects, outputting fields that most closely correspond to available observational datasets.

School Emergency Preparedness in North Dakota Public School Districts

ERIC Educational Resources Information Center

Swiontek, Steven Wayne

2009-01-01

The basis for this study was to determine: (1) If school districts in North Dakota have an emergency response plan; (2) How comprehensive their emergency response plan is; (3) How well prepared school districts in North Dakota are for any type of disaster; and (4) The extent to which North Dakota LEAD Center school emergency response training and…

Establishment of CDC Global Rapid Response Team to Ensure Global Health Security.

PubMed

Stehling-Ariza, Tasha; Lefevre, Adrienne; Calles, Dinorah; Djawe, Kpandja; Garfield, Richard; Gerber, Michael; Ghiselli, Margherita; Giese, Coralie; Greiner, Ashley L; Hoffman, Adela; Miller, Leigh Ann; Moorhouse, Lisa; Navarro-Colorado, Carlos; Walsh, James; Bugli, Dante; Shahpar, Cyrus

2017-12-01

The 2014-2016 Ebola virus disease epidemic in West Africa highlighted challenges faced by the global response to a large public health emergency. Consequently, the US Centers for Disease Control and Prevention established the Global Rapid Response Team (GRRT) to strengthen emergency response capacity to global health threats, thereby ensuring global health security. Dedicated GRRT staff can be rapidly mobilized for extended missions, improving partner coordination and the continuity of response operations. A large, agencywide roster of surge staff enables rapid mobilization of qualified responders with wide-ranging experience and expertise. Team members are offered emergency response training, technical training, foreign language training, and responder readiness support. Recent response missions illustrate the breadth of support the team provides. GRRT serves as a model for other countries and is committed to strengthening emergency response capacity to respond to outbreaks and emergencies worldwide, thereby enhancing global health security.

Ultrafine particle measurement and related EPA research studies

EPA Science Inventory

Webinar slides to present information on measuring ultrafine particles at the request of the 2013 MARAMA Monitoring Committee. The talk covers near-road monitoring, instrument intercomparison, and general overview of UFP monitoring technology.

Determining the Relationship between the Total and Window Channel Nighttime Radiances for the CERES Instrument

NASA Technical Reports Server (NTRS)

Kratz, David P.; Priestley, Kory J.; Green, Richard N.

1999-01-01

Observing Earth s radiant energy budget from space is critical to improving our understanding of Earth s climate system. The Earth Radiation Budget Experiment (ERBE) was the first initiative to provide simultaneous observations of Earth s radiant energy with identical instruments flying aboard separate satellites. The design of the ERBE instrument was based upon three complementary broadband radiometers which measured the shortwave (< 5 mm), longwave (> 5 mm), and total regions of the spectrum. Since any two of the ERBE radiometers could be used to simulate the third, a three channel intercomparison, based on redundancy, was available to uncover any changes in the relative sensitivities of the individual radiometers. Such a three channel intercomparison thus provided confidence in the application of the ERBE measurements over the lifetime of the instrument while mitigating the concern over instrument degradation.

Intercomparisons of high-resolution solar blind Raman lidar atmospheric profiles of water vapor with radiosondes and kytoon

NASA Technical Reports Server (NTRS)

Petri, K.; Salik, A.; Cooney, J.

1986-01-01

A report is given of measurements of atmospheric profiles of water vapor in the boundary layer by use of solar blind Raman lidar. These measurement episodes, occuring twice a day over a two week period, were accompanied by a dense net of supporting measurements. The support included two radiosonde launches per measurement episodes as well as a kytoon support measurement of water vapor using a wet bulb-dry bulb instrument. The kytoon strategy included ten minute stops at strategic altitudes. Additional kytoon measurements included ozone profiles and nephelometric extinction profiles in the visible. Typically, six or seven 1000 shot lidar profile averages were collected during a measurement episode. Overall performance comparisons are provided and intercomparisons between auxiliary measurement devices are presented. Data on the accuracy of the lidar water vapor profiles are presented.

Fast and slow responses of Southern Ocean sea surface temperature to SAM in coupled climate models

NASA Astrophysics Data System (ADS)

Kostov, Yavor; Marshall, John; Hausmann, Ute; Armour, Kyle C.; Ferreira, David; Holland, Marika M.

2017-03-01

We investigate how sea surface temperatures (SSTs) around Antarctica respond to the Southern Annular Mode (SAM) on multiple timescales. To that end we examine the relationship between SAM and SST within unperturbed preindustrial control simulations of coupled general circulation models (GCMs) included in the Climate Modeling Intercomparison Project phase 5 (CMIP5). We develop a technique to extract the response of the Southern Ocean SST (55°S-70°S) to a hypothetical step increase in the SAM index. We demonstrate that in many GCMs, the expected SST step response function is nonmonotonic in time. Following a shift to a positive SAM anomaly, an initial cooling regime can transition into surface warming around Antarctica. However, there are large differences across the CMIP5 ensemble. In some models the step response function never changes sign and cooling persists, while in other GCMs the SST anomaly crosses over from negative to positive values only 3 years after a step increase in the SAM. This intermodel diversity can be related to differences in the models' climatological thermal ocean stratification in the region of seasonal sea ice around Antarctica. Exploiting this relationship, we use observational data for the time-mean meridional and vertical temperature gradients to constrain the real Southern Ocean response to SAM on fast and slow timescales.

30 CFR 254.23 - What information must I include in the “Emergency response action plan” section?

Code of Federal Regulations, 2013 CFR

2013-07-01

... LOCATED SEAWARD OF THE COAST LINE Oil-Spill Response Plans for Outer Continental Shelf Facilities § 254.23 What information must I include in the “Emergency response action plan” section? The “Emergency response action plan” section is the core of the response plan. Put information in easy-to-use formats such...

30 CFR 254.23 - What information must I include in the “Emergency response action plan” section?

Code of Federal Regulations, 2011 CFR

2011-07-01

... FOR FACILITIES LOCATED SEAWARD OF THE COAST LINE Oil-Spill Response Plans for Outer Continental Shelf Facilities § 254.23 What information must I include in the “Emergency response action plan” section? The “Emergency response action plan”section is the core of the response plan. Put information in easy-to-use...

30 CFR 254.23 - What information must I include in the “Emergency response action plan” section?

Code of Federal Regulations, 2014 CFR

2014-07-01

... LOCATED SEAWARD OF THE COAST LINE Oil-Spill Response Plans for Outer Continental Shelf Facilities § 254.23 What information must I include in the “Emergency response action plan” section? The “Emergency response action plan” section is the core of the response plan. Put information in easy-to-use formats such...

30 CFR 254.23 - What information must I include in the “Emergency response action plan” section?

Code of Federal Regulations, 2012 CFR

2012-07-01

... LOCATED SEAWARD OF THE COAST LINE Oil-Spill Response Plans for Outer Continental Shelf Facilities § 254.23 What information must I include in the “Emergency response action plan” section? The “Emergency response action plan” section is the core of the response plan. Put information in easy-to-use formats such...

10 CFR 50.47 - Emergency plans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... responsibilities for emergency response by the nuclear facility licensee and by State and local organizations... supporting organizations have been specifically established, and each principal response organization has... licensee's near-site Emergency Operations Facility have been made, and other organizations capable of...

40 CFR 300.4 - Abbreviations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Function FCO—Federal Coordinating Officer FRERP—Federal Radiological Emergency Response Plan FRP—Federal Response Plan FS—Feasibility Study HRS—Hazard Ranking System LEPC—Local Emergency Planning Committee NCP... Action RCP—Regional Contingency Plan RD—Remedial Design RERT—Radiological Emergency Response Team RI...

40 CFR 300.4 - Abbreviations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Function FCO—Federal Coordinating Officer FRERP—Federal Radiological Emergency Response Plan FRP—Federal Response Plan FS—Feasibility Study HRS—Hazard Ranking System LEPC—Local Emergency Planning Committee NCP... Action RCP—Regional Contingency Plan RD—Remedial Design RERT—Radiological Emergency Response Team RI...

40 CFR 300.4 - Abbreviations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Function FCO—Federal Coordinating Officer FRERP—Federal Radiological Emergency Response Plan FRP—Federal Response Plan FS—Feasibility Study HRS—Hazard Ranking System LEPC—Local Emergency Planning Committee NCP... Action RCP—Regional Contingency Plan RD—Remedial Design RERT—Radiological Emergency Response Team RI...

40 CFR 300.4 - Abbreviations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Function FCO—Federal Coordinating Officer FRERP—Federal Radiological Emergency Response Plan FRP—Federal Response Plan FS—Feasibility Study HRS—Hazard Ranking System LEPC—Local Emergency Planning Committee NCP... Action RCP—Regional Contingency Plan RD—Remedial Design RERT—Radiological Emergency Response Team RI...

75 FR 15362 - Demand Response Compensation in Organized Wholesale Energy Markets

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-29

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission 18 CFR Part 35 [Docket No. RM10-17-000... FERC ] 61,213, PJM Interconnection, LLC, Docket No. EL09-68-000 Notice of Proposed Rulemaking Table of... Emergency Demand Response; NYISO's Emergency Demand Response Program; PJM's Emergency Load Response; and ISO...

A Building-Resolved Wind Field Library for Vancouver: Facilitating CBRN Emergency Response for the 2010 Winter Olympic Games

DTIC Science & Technology

2010-06-01

Vancouver. Facilitating CBRN Emergency Response for the 2010 Winter Olympic Games E. Vee Defence R&D Canada- Suffield F.-S. Lien University of...ana a A Building-Resolved Wind Field Library for Vancouver. Facilitating CBRN Emergency Response for the 2010 Winter Olympic Games E. Yee Defence...support of emergency response applications (requiring quick turn- around times) for the 2010 Winter Olympic Games . To this purpose, mean wind and

Error analysis for the ground-based microwave ozone measurements during STOIC

NASA Technical Reports Server (NTRS)

Connor, Brian J.; Parrish, Alan; Tsou, Jung-Jung; McCormick, M. Patrick

1995-01-01

We present a formal error analysis and characterization of the microwave measurements made during the Stratospheric Ozone Intercomparison Campaign (STOIC). The most important error sources are found to be determination of the tropospheric opacity, the pressure-broadening coefficient of the observed line, and systematic variations in instrument response as a function of frequency ('baseline'). Net precision is 4-6% between 55 and 0.2 mbar, while accuracy is 6-10%. Resolution is 8-10 km below 3 mbar and increases to 17km at 0.2 mbar. We show the 'blind' microwave measurements from STOIC and make limited comparisons to other measurements. We use the averaging kernels of the microwave measurement to eliminate resolution and a priori effects from a comparison to SAGE 2. The STOIC results and comparisons are broadly consistent with the formal analysis.

Aviation Fuel Tracer Simulation: Model Intercomparison and Implications

NASA Technical Reports Server (NTRS)

Danilin, M. Y.; Fahey, D. W.; Schumann, U.; Prather, M. J.; Penner, J. E.; Ko, M. K. W.; Weisenstein, D. K.; Jackman, C. H.; Pitari, G.; Koehler, I.;

In Situ Aerosol Optical Thickness Collected by the SIMBIOS Program (1997-2000): Protocols, and and Data QC and Analysis

NASA Technical Reports Server (NTRS)

Fargion, Giulietta S.; Barnes, Robert; McClain, Charles

2001-01-01

The purpose of this technical report is to provide current documentation of the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project Office activities on in situ aerosol optical thickness (i.e., protocols, and data QC and analysis). This documentation is necessary to ensure that critical information is related to the scientific community and NASA management. This critical information includes the technical difficulties and challenges of validating and combining ocean color data from an array of independent satellite systems to form consistent and accurate global bio-optical time series products. This technical report is not meant as a substitute for scientific literature. Instead, it will provide a ready and responsive vehicle for the multitude of technical reports issued by an operational project.

Aviation Fuel Tracer Simulation: Model Intercomparison and Implications

NASA Technical Reports Server (NTRS)

Danilin, M. Y.; Fahey, D. W.; Schumann, U.; Prather, M. J.; Penner, J. E.; Ko, M. K. W.; Weisenstein, D. K.; Jackman, C. H.; Pitari, G.; Koehler, I.;

Addressing the gap between public health emergency planning and incident response

PubMed Central

Freedman, Ariela M; Mindlin, Michele; Morley, Christopher; Griffin, Meghan; Wooten, Wilma; Miner, Kathleen

2013-01-01

Objectives: Since 9/11, Incident Command System (ICS) and Emergency Operations Center (EOC) are relatively new concepts to public health, which typically operates using less hierarchical and more collaborative approaches to organizing staff. This paper describes the 2009 H1N1 influenza outbreak in San Diego County to explore the use of ICS and EOC in public health emergency response. Methods: This study was conducted using critical case study methodology consisting of document review and 18 key-informant interviews with individuals who played key roles in planning and response. Thematic analysis was used to analyze data. Results: Several broad elements emerged as key to ensuring effective and efficient public health response: 1) developing a plan for emergency response; 2) establishing the framework for an ICS; 3) creating the infrastructure to support response; 4) supporting a workforce trained on emergency response roles, responsibilities, and equipment; and 5) conducting regular preparedness exercises. Conclusions: This research demonstrates the value of investments made and that effective emergency preparedness requires sustained efforts to maintain personnel and material resources. By having the infrastructure and experience based on ICS and EOC, the public health system had the capability to surge-up: to expand its day-to-day operation in a systematic and prolonged manner. None of these critical actions are possible without sustained funding for the public health infrastructure. Ultimately, this case study illustrates the importance of public health as a key leader in emergency response. PMID:28228983

The Earth System Grid Federation (ESGF): Climate Science Infrastructure for Large-scale Data Management and Dissemination

NASA Astrophysics Data System (ADS)

Williams, D. N.

2015-12-01

Progress in understanding and predicting climate change requires advanced tools to securely store, manage, access, process, analyze, and visualize enormous and distributed data sets. Only then can climate researchers understand the effects of climate change across all scales and use this information to inform policy decisions. With the advent of major international climate modeling intercomparisons, a need emerged within the climate-change research community to develop efficient, community-based tools to obtain relevant meteorological and other observational data, develop custom computational models, and export analysis tools for climate-change simulations. While many nascent efforts to fill these gaps appeared, they were not integrated and therefore did not benefit from collaborative development. Sharing huge data sets was difficult, and the lack of data standards prevented the merger of output data from different modeling groups. Thus began one of the largest-ever collaborative data efforts in climate science, resulting in the Earth System Grid Federation (ESGF), which is now used to disseminate model, observational, and reanalysis data for research assessed by the Intergovernmental Panel on Climate Change (IPCC). Today, ESGF is an open-source petabyte-level data storage and dissemination operational code-base that manages secure resources essential for climate change study. It is designed to remain robust even as data volumes grow exponentially. The internationally distributed, peer-to-peer ESGF "data cloud" archive represents the culmination of an effort that began in the late 1990s. ESGF portals are gateways to scientific data collections hosted at sites around the globe that allow the user to register and potentially access the entire ESGF network of data and services. The growing international interest in ESGF development efforts has attracted many others who want to make their data more widely available and easy to use. For example, the World Climate Research Program, which provides governance for CMIP, has now endorsed the ESGF software foundation to be used for ~70 other model intercomparison projects (MIPs), such as obs4MIPs, TAMIP, CFMIP, and GeoMIP. At present, more than 40 projects disseminate their data via ESGF.

Intelligent transportation systems field operational test cross-cutting study : emergency notification and response.

DOT National Transportation Integrated Search

1998-09-01

Emergency Notification and Response report summarizes and interprets the results of two Field Operational Tests (FOTs) that included emergency notification and response system components. The tests included in this report are: Colorado Mayday and Pug...

47 CFR 0.192 - Emergency Response Interoperability Center.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 1 2014-10-01 2014-10-01 false Emergency Response Interoperability Center. 0.192 Section 0.192 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMISSION ORGANIZATION Organization Public Safety and Homeland Security Bureau § 0.192 Emergency Response Interoperability Center. (a...

47 CFR 0.192 - Emergency Response Interoperability Center.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 1 2013-10-01 2013-10-01 false Emergency Response Interoperability Center. 0.192 Section 0.192 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMISSION ORGANIZATION Organization Public Safety and Homeland Security Bureau § 0.192 Emergency Response Interoperability Center. (a...

47 CFR 0.192 - Emergency Response Interoperability Center.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 1 2011-10-01 2011-10-01 false Emergency Response Interoperability Center. 0.192 Section 0.192 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMISSION ORGANIZATION Organization Public Safety and Homeland Security Bureau § 0.192 Emergency Response Interoperability Center. (a...

44 CFR 352.25 - Limitation on committing Federal facilities and resources for emergency preparedness.

Code of Federal Regulations, 2013 CFR

2013-10-01

... licensee offsite emergency response plan only to the extent necessary to compensate for the... response plan. ... Federal facilities and resources for emergency preparedness. 352.25 Section 352.25 Emergency Management...

44 CFR 352.25 - Limitation on committing Federal facilities and resources for emergency preparedness.

Code of Federal Regulations, 2014 CFR

2014-10-01

... licensee offsite emergency response plan only to the extent necessary to compensate for the... response plan. ... Federal facilities and resources for emergency preparedness. 352.25 Section 352.25 Emergency Management...

44 CFR 352.25 - Limitation on committing Federal facilities and resources for emergency preparedness.

Code of Federal Regulations, 2012 CFR

2012-10-01

... licensee offsite emergency response plan only to the extent necessary to compensate for the... response plan. ... Federal facilities and resources for emergency preparedness. 352.25 Section 352.25 Emergency Management...

Incident Management Systems and Building Emergency Management Capacity during the 2014-2016 Ebola Epidemic - Liberia, Sierra Leone, and Guinea.

PubMed

Brooks, Jennifer C; Pinto, Meredith; Gill, Adrienne; Hills, Katherine E; Murthy, Shivani; Podgornik, Michelle N; Hernandez, Luis F; Rose, Dale A; Angulo, Frederick J; Rzeszotarski, Peter

2016-07-08

Establishing a functional incident management system (IMS) is important in the management of public health emergencies. In response to the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC established the Emergency Management Development Team (EMDT) to coordinate technical assistance for developing emergency management capacity in Guinea, Liberia, and Sierra Leone. EMDT staff, deployed staff, and partners supported each country to develop response goals and objectives, identify gaps in response capabilities, and determine strategies for coordinating response activities. To monitor key programmatic milestones and assess changes in emergency management and response capacities over time, EMDT implemented three data collection methods in country: coordination calls, weekly written situation reports, and an emergency management dashboard tool. On the basis of the information collected, EMDT observed improvements in emergency management capacity over time in all three countries. The collaborations in each country yielded IMS structures that streamlined response and laid the foundation for long-term emergency management programs.The activities summarized in this report would not have been possible without collaboration with many U.S and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

The knowledge, attitude and behavior about public health emergencies and the response capacity of primary care medical staffs of Guangdong Province, China

PubMed Central

2012-01-01

Background Primary care medical staffs’ knowledge, attitude and behavior about health emergency and the response capacity are directly related to the control and prevention of public health emergencies. Therefore, it is of great significance for improving primary care to gain in-depth knowledge about knowledge, attitude and behavior and the response capacity of primary care medical staffs. The main objective of this study is to explore knowledge, attitude and behavior, and the response capacity of primary care medical staffs of Guangdong Province, China. Methods Stratified clustered sample method was used in the anonymous questionnaire investigation about knowledge, attitude and behavior, and the response capacity of 3410 primary care medical staffs in 15 cities of Guangdong Province, China from July, 2010 to October 2010. The emergency response capacity was evaluated by 33 questions. The highest score of the response capacity was 100 points (full score), score of 70 was a standard. Results 62.4% primary care medical staffs believed that public health emergencies would happen. Influenza (3.86 ± 0.88), food poisoning (3.35 ± 0.75), and environmental pollution events (3.23 ± 0.80) (the total score was 5) were considered most likely to occur. Among the 7 public health emergency skills, the highest self-assessment score is “public health emergency prevention skills” (2.90 ± 0.68), the lowest is “public health emergency risk management (the total score was 5)” (1.81 ± 0.40). Attitude evaluation showed 66.1% of the medical staffs believed that the community awareness of risk management were ordinary. Evaluation of response capacity of health emergency showed that the score of primary care medical staffs was 67.23 ± 10.61, and the response capacity of senior physicians, public health physicians and physicians with relatively long-term practice were significantly better (P <0.05). Multiple linear stepwise regression analysis showed gender, title, position, type of work, work experience and whether to participate relative training were the main factors affecting the health emergency response capacity. Conclusions The knowledge, attitude and behavior about public health emergencies and the response capacity of primary care medical staffs of Guangdong Province (China) were poor. Health administrative departments should strengthen the training of health emergency knowledge and skills of the primary care medical staffs to enhance their health emergency response capabilities. PMID:23009075

New Sentinel-2 radiometric validation approaches (SEOM program)

NASA Astrophysics Data System (ADS)

Bruniquel, Véronique; Lamquin, Nicolas; Ferron, Stéphane; Govaerts, Yves; Woolliams, Emma; Dilo, Arta; Gascon, Ferran

2016-04-01

SEOM is an ESA program element whose one of the objectives aims at launching state-of-the-art studies for the scientific exploitation of operational missions. In the frame of this program, ESA awarded ACRI-ST and its partners Rayference and National Physical Laboratory (NPL) early 2016 for a R&D study on the development and intercomparison of algorithms for validating the Sentinel-2 radiometric L1 data products beyond the baseline algorithms used operationally in the frame of the S2 Mission Performance Centre. In this context, several algorithms have been proposed and are currently in development: The first one is based on the exploitation of Deep Convective Cloud (DCC) observations over ocean. This method allows an inter-band radiometry validation from the blue to the NIR (typically from B1 to B8a) from a reference band already validated for example with the well-known Rayleigh method. Due to their physical properties, DCCs appear from the remote sensing point of view to have bright and cold tops and they can be used as invariant targets to monitor the radiometric response degradation of reflective solar bands. The DCC approach is statistical i.e. the method shall be applied on a large number of measurements to derive reliable statistics and decrease the impact of the perturbing contributors. The second radiometric validation method is based on the exploitation of matchups combining both concomitant in-situ measurements and Sentinel-2 observations. The in-situ measurements which are used here correspond to measurements acquired in the frame of the RadCalNet networks. The validation is performed for the Sentinel-2 bands similar to the bands of the instruments equipping the validation site. The measurements from the Cimel CE 318 12-filters BRDF Sun Photometer installed recently in the Gobabeb site near the Namib desert are used for this method. A comprehensive verification of the calibration requires an analysis of MSI radiances over the full dynamic range, including low radiances, as extreme values are more subject to instrument response non-linearity. The third method developed in the frame of this project aims to address this point. It is based on a comparison of Sentinel-2 observations over coastal waters which have low radiometry and corresponding Radiative Transfer (RT) simulations using AERONET-OC measurements. Finally, a last method is developed using RadCalNet measurements and Sentinel-2 observations to validate the radiometry of mid/low resolution sensors such as Sentinel-3/OLCI. The RadCalNet measurements are transferred from the RadCalNet sites to Pseudo Invariant Calibration Sites (PICS) using Sentinel-2, and then these larger sites are used to validate mid- and low-resolution sensors to the RadCalNet reference. For all the developed methods, an uncertainty budget is derived following QA4EO guidelines. A last step of this ESA project is dedicated to an Inter-comparison Workshop open to entities involved in Sentinel-2 radiometric validation activities. Blind inter-comparison tests over a series of images will be proposed and the results will be discussed during the workshop.

Contraceptive availability during an emergency response in the United States.

PubMed

Ellington, Sascha R; Kourtis, Athena P; Curtis, Kathryn M; Tepper, Naomi; Gorman, Susan; Jamieson, Denise J; Zotti, Marianne; Barfield, Wanda

2013-03-01

This article provides the evidence for contraceptive need to prevent unintended pregnancy during an emergency response, discusses the most appropriate types of contraceptives for disaster situations, and details the current provisions in place to provide contraceptives during an emergency response.

40 CFR 68.180 - Emergency response program.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Emergency response program. 68.180 Section 68.180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CHEMICAL ACCIDENT PREVENTION PROVISIONS Risk Management Plan § 68.180 Emergency response program...

Emergent intraverbal responses via tact and match-to-sample instruction.

PubMed

Grannan, Leigh; Rehfeldt, Ruth Anne

2012-01-01

The present investigation evaluated the effectiveness of category tact and match-to-sample instruction in facilitating the emergence of intraverbal responses (i.e., naming several items belonging to a specific category) for 2 children with autism. Results demonstrated the emergence of untaught responses, suggesting an effective instructional protocol for establishing intraverbal responses without direct instruction.

CMIP5 models' shortwave cloud radiative response and climate sensitivity linked to the climatological Hadley cell extent

NASA Astrophysics Data System (ADS)

Lipat, Bernard R.; Tselioudis, George; Grise, Kevin M.; Polvani, Lorenzo M.

2017-06-01

This study analyzes Coupled Model Intercomparison Project phase 5 (CMIP5) model output to examine the covariability of interannual Southern Hemisphere Hadley cell (HC) edge latitude shifts and shortwave cloud radiative effect (SWCRE). In control climate runs, during years when the HC edge is anomalously poleward, most models substantially reduce the shortwave radiation reflected by clouds in the lower midlatitude region (LML; ˜28°S-˜48°S), although no such reduction is seen in observations. These biases in HC-SWCRE covariability are linked to biases in the climatological HC extent. Notably, models with excessively equatorward climatological HC extents have weaker climatological LML subsidence and exhibit larger increases in LML subsidence with poleward HC edge expansion. This behavior, based on control climate interannual variability, has important implications for the CO2-forced model response. In 4×CO2-forced runs, models with excessively equatorward climatological HC extents produce stronger SW cloud radiative warming in the LML region and tend to have larger climate sensitivity values than models with more realistic climatological HC extents.

The Response of the North American Monsoon to Increased Greenhouse Gas Forcing

NASA Technical Reports Server (NTRS)

Cook, B. I.; Seager, R.

2013-01-01

[1] We analyze the response of the North American Monsoon (NAM) to increased greenhouse gas (GHG) forcing (emissions scenario RCP 8.5) using new simulations available through the Coupled Model Intercomparison Project version 5 (CMIP5). Changes in total monsoon season rainfall with GHG warming are small and insignificant. The models do, however, show significant declines in early monsoon season precipitation (June-July) and increases in late monsoon season (September-October) precipitation, indicating a shift in seasonality toward delayed onset and withdrawal of the monsoon. Early in the monsoon season, tropospheric warming increases vertical stability, reinforced by reductions in available surface moisture, inhibiting precipitation and delaying the onset of the monsoon. By the end of the monsoon season, moisture convergence is sufficient to overcome the warming induced stability increases, and precipitation is enhanced. Even with no change in total NAM rainfall, shifts in the seasonal distribution of precipitation within the NAM region are still likely to have significant societal and ecological consequences, reinforcing the need to not only understand the magnitude, but also the timing, of future precipitation changes.

A possible explanation for the divergent projection of ENSO amplitude change under global warming

NASA Astrophysics Data System (ADS)

Chen, Lin; Li, Tim; Yu, Yongqiang; Behera, Swadhin K.

2017-12-01

The El Niño-Southern Oscillation (ENSO) is the greatest climate variability on interannual time scale, yet what controls ENSO amplitude changes under global warming (GW) is uncertain. Here we show that the fundamental factor that controls the divergent projections of ENSO amplitude change within 20 coupled general circulation models that participated in the Coupled Model Intercomparison Project phase-5 is the change of climatologic mean Pacific subtropical cell (STC), whose strength determines the meridional structure of ENSO perturbations and thus the anomalous thermocline response to the wind forcing. The change of the thermocline response is a key factor regulating the strength of Bjerknes thermocline and zonal advective feedbacks, which ultimately lead to the divergent changes in ENSO amplitude. Furthermore, by forcing an ocean general circulation mode with the change of zonal mean zonal wind stress estimated by a simple theoretical model, a weakening of the STC in future is obtained. Such a change implies that ENSO variability might strengthen under GW, which could have a profound socio-economic consequence.

Limited influence of climate change mitigation on short-term glacier mass loss

NASA Astrophysics Data System (ADS)

Marzeion, Ben; Kaser, Georg; Maussion, Fabien; Champollion, Nicolas

2018-04-01

Glacier mass loss is a key contributor to sea-level change1,2, slope instability in high-mountain regions3,4 and the changing seasonality and volume of river flow5-7. Understanding the causes, mechanisms and time scales of glacier change is therefore paramount to identifying successful strategies for mitigation and adaptation. Here, we use temperature and precipitation fields from the Coupled Model Intercomparison Project Phase 5 output to force a glacier evolution model, quantifying mass responses to future climatic change. We find that contemporary glacier mass is in disequilibrium with the current climate, and 36 ± 8% mass loss is already committed in response to past greenhouse gas emissions. Consequently, mitigating future emissions will have only very limited influence on glacier mass change in the twenty-first century. No significant differences between 1.5 and 2 K warming scenarios are detectable in the sea-level contribution of glaciers accumulated within the twenty-first century. In the long-term, however, mitigation will exert strong control, suggesting that ambitious measures are necessary for the long-term preservation of glaciers.

Response of the North Pacific Oscillation to global warming in the models of the Intergovernmental Panel on Climate Change Fourth Assessment Report

NASA Astrophysics Data System (ADS)

Chen, Zheng; Gan, Bolan; Wu, Lixin

2017-09-01

Based on 22 of the climate models from phase 3 of the Coupled Model Intercomparison Project, we investigate the ability of the models to reproduce the spatiotemporal features of the wintertime North Pacific Oscillation (NPO), which is the second most important factor determining the wintertime sea level pressure field in simulations of the pre-industrial control climate, and evaluate the NPO response to the future most reasonable global warming scenario (the A1B scenario). We reveal that while most models simulate the geographic distribution and amplitude of the NPO pattern satisfactorily, only 13 models capture both features well. However, the temporal variability of the simulated NPO could not be significantly correlated with the observations. Further analysis indicates the weakened NPO intensity for a scenario of strong global warming is attributable to the reduced lower-tropospheric baroclinicity at mid-latitudes, which is anticipated to disrupt large-scale and low-frequency atmospheric variability, resulting in the diminished transfer of energy to the NPO, together with its northward shift.

Exploratory analysis of real personal emergency response call conversations: considerations for personal emergency response spoken dialogue systems.

PubMed

Young, Victoria; Rochon, Elizabeth; Mihailidis, Alex

2016-11-14

The purpose of this study was to derive data from real, recorded, personal emergency response call conversations to help improve the artificial intelligence and decision making capability of a spoken dialogue system in a smart personal emergency response system. The main study objectives were to: develop a model of personal emergency response; determine categories for the model's features; identify and calculate measures from call conversations (verbal ability, conversational structure, timing); and examine conversational patterns and relationships between measures and model features applicable for improving the system's ability to automatically identify call model categories and predict a target response. This study was exploratory and used mixed methods. Personal emergency response calls were pre-classified according to call model categories identified qualitatively from response call transcripts. The relationships between six verbal ability measures, three conversational structure measures, two timing measures and three independent factors: caller type, risk level, and speaker type, were examined statistically. Emergency medical response services were the preferred response for the majority of medium and high risk calls for both caller types. Older adult callers mainly requested non-emergency medical service responders during medium risk situations. By measuring the number of spoken words-per-minute and turn-length-in-words for the first spoken utterance of a call, older adult and care provider callers could be identified with moderate accuracy. Average call taker response time was calculated using the number-of-speaker-turns and time-in-seconds measures. Care providers and older adults used different conversational strategies when responding to call takers. The words 'ambulance' and 'paramedic' may hold different latent connotations for different callers. The data derived from the real personal emergency response recordings may help a spoken dialogue system classify incoming calls by caller type with moderate probability shortly after the initial caller utterance. Knowing the caller type, the target response for the call may be predicted with some degree of probability and the output dialogue could be tailored to this caller type. The average call taker response time measured from real calls may be used to limit the conversation length in a spoken dialogue system before defaulting to a live call taker.

Emergency Response Virtual Environment for Safe Schools

NASA Technical Reports Server (NTRS)

Wasfy, Ayman; Walker, Teresa

2008-01-01

An intelligent emergency response virtual environment (ERVE) that provides emergency first responders, response planners, and managers with situational awareness as well as training and support for safe schools is presented. ERVE incorporates an intelligent agent facility for guiding and assisting the user in the context of the emergency response operations. Response information folders capture key information about the school. The system enables interactive 3D visualization of schools and academic campuses, including the terrain and the buildings' exteriors and interiors in an easy to use Web..based interface. ERVE incorporates live camera and sensors feeds and can be integrated with other simulations such as chemical plume simulation. The system is integrated with a Geographical Information System (GIS) to enable situational awareness of emergency events and assessment of their effect on schools in a geographic area. ERVE can also be integrated with emergency text messaging notification systems. Using ERVE, it is now possible to address safe schools' emergency management needs with a scaleable, seamlessly integrated and fully interactive intelligent and visually compelling solution.

Simulated vs. empirical weather responsiveness of crop yields: US evidence and implications for the agricultural impacts of climate change

DOE PAGES

Mistry, Malcolm N.; Wing, Ian Sue; De Cian, Enrica

2017-07-10

Global gridded crop models (GGCMs) are the workhorse of assessments of the agricultural impacts of climate change. Yet the changes in crop yields projected by different models in response to the same meteorological forcing can differ substantially. Through an inter-method comparison, we provide a first glimpse into the origins and implications of this divergence—both among GGCMs and between GGCMs and historical observations. We examine yields of rainfed maize, wheat, and soybeans simulated by six GGCMs as part of the Inter-Sectoral Impact Model Intercomparison Project-Fast Track (ISIMIP-FT) exercise, comparing 1981–2004 hindcast yields over the coterminous United States (US) against US Departmentmore » of Agriculture (USDA) time series for about 1000 counties. Leveraging the empirical climate change impacts literature, we estimate reduced-form econometric models of crop yield responses to temperature and precipitation exposures for both GGCMs and observations. We find that up to 60% of the variance in both simulated and observed yields is attributable to weather variation. A majority of the GGCMs have difficulty reproducing the observed distribution of percentage yield anomalies, and exhibit aggregate responses that show yields to be more weather-sensitive than in the observational record over the predominant range of temperature and precipitation conditions. In conclusion, this disparity is largely attributable to heterogeneity in GGCMs' responses, as opposed to uncertainty in historical weather forcings, and is responsible for widely divergent impacts of climate on future crop yields.« less

Simulated vs. empirical weather responsiveness of crop yields: US evidence and implications for the agricultural impacts of climate change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mistry, Malcolm N.; Wing, Ian Sue; De Cian, Enrica

Global gridded crop models (GGCMs) are the workhorse of assessments of the agricultural impacts of climate change. Yet the changes in crop yields projected by different models in response to the same meteorological forcing can differ substantially. Through an inter-method comparison, we provide a first glimpse into the origins and implications of this divergence—both among GGCMs and between GGCMs and historical observations. We examine yields of rainfed maize, wheat, and soybeans simulated by six GGCMs as part of the Inter-Sectoral Impact Model Intercomparison Project-Fast Track (ISIMIP-FT) exercise, comparing 1981–2004 hindcast yields over the coterminous United States (US) against US Departmentmore » of Agriculture (USDA) time series for about 1000 counties. Leveraging the empirical climate change impacts literature, we estimate reduced-form econometric models of crop yield responses to temperature and precipitation exposures for both GGCMs and observations. We find that up to 60% of the variance in both simulated and observed yields is attributable to weather variation. A majority of the GGCMs have difficulty reproducing the observed distribution of percentage yield anomalies, and exhibit aggregate responses that show yields to be more weather-sensitive than in the observational record over the predominant range of temperature and precipitation conditions. In conclusion, this disparity is largely attributable to heterogeneity in GGCMs' responses, as opposed to uncertainty in historical weather forcings, and is responsible for widely divergent impacts of climate on future crop yields.« less