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22 results on '"Atmospheric and Environmental Research, Inc. (AER)"'

1. Impact of Continental Freshwater Runoff on Coastal Sea Level

Author

Rui M. Ponte, Christopher G. Piecuch, Jamal Uddin Khan, Sherin V. Raju, Fabrice Papa, Fabien Durand, Melanie Becker, Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Woods Hole Oceanographic Institution (WHOI), LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Indo-French Cell for Water Sciences (IFCWS), Indian Institute of Science [Bangalore] (IISc Bangalore), Institute of Water and Flood Management, Bangladesh University of Engineering and Technology, Atmospheric and Environmental Research, Inc. (AER), ANR-17-CE03-0001,DELTA,Les deltas sous l'impact du changement global(2017), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), LIttoral ENvironnement et Sociétés (LIENSs), and La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, [SDE.MCG]Environmental Sciences/Global Changes, Baroclinity, Observational techniques, Forcing (mathematics), 010502 geochemistry & geophysics, 01 natural sciences, Current (stream), Geophysics, Oceanography, 13. Climate action, Geochemistry and Petrology, Others, Barotropic fluid, Environmental science, 14. Life underwater, Temporal scales, Surface runoff, Sea level, 0105 earth and related environmental sciences
Abstract

International audience; Freshwater discharge to the coastal ocean is a fundamental component of the global water cycle. It can impact coastal sea level over a broad range of spatial and temporal scales. Here we review the status of the current knowledge based on observational and modeling approaches. The main limitation in studies of the influence of rivers on coastal sea level has been the lack of consolidated discharge databases. We first provide an inventory of the main data sources currently available. We then review the existing knowledge about the runoff forcing of coastal sea level, differentiating between the mass and steric height contributions. Both mechanisms are important for coastal sea level budget, although they act on different scales. The mass contribution is related to a global ocean response that is established on relatively short timescales through barotropic processes while the steric contribution is associated with more of a regional adjustment that takes place on longer timescales by means of baroclinic dynamics. While numerical models required to simulate the runoff impact on coastal sea level variability have been improving over the past decades , a similar evolution is awaited for observational techniques, both for in situ observation and for remote sensing.

Published
2019
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2. 10-year satellite-constrained fluxes of ammonia improve performance of chemistry transport models

Author

Anne Cozic, Nikolaos Evangeliou, Lieven Clarisse, Sabine Eckhardt, Yves Balkanski, Pierre-François Coheur, Martin Van Damme, Didier Hauglustaine, Karen Cady-Pereira, Mark W. Shephard, Norwegian Institute for Air Research (NILU), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (SQUARES), Université libre de Bruxelles (ULB), Environment and Climate Change Canada, Atmospheric and Environmental Research, Inc. (AER), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Calcul Scientifique (CALCULS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, North china, 010501 environmental sciences, engineering.material, Atmospheric sciences, 01 natural sciences, Late summer, lcsh:Chemistry, chemistry.chemical_compound, Ammonia, Phénomènes atmosphériques, medicine, Sulfate, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], business.industry, Seasonality, medicine.disease, lcsh:QC1-999, lcsh:QD1-999, chemistry, Agriculture, [SDE]Environmental Sciences, engineering, Satellite, Fertilizer, business, lcsh:Physics
Abstract

In recent years, ammonia emissions have been continuously increasing, being almost 4 times higher than in the 20th century. Although an important species, as its use as a fertilizer sustains human living, ammonia has major consequences for both humans and the environment because of its reactive gas-phase chemistry that makes it easily convertible to particles. Despite its pronounced importance, ammonia emissions are highly uncertain in most emission inventories. However, the great development of satellite remote sensing nowadays provides the opportunity for more targeted research on constraining ammonia emissions. Here, we used satellite measurements to calculate global ammonia emissions over the period 2008 2017. Then, the calculated ammonia emissions were fed to a chemistry transport model, and ammonia concentrations were simulated for the period 2008 2017. The simulated concentrations of ammonia were compared with ground measurements from Europe, North America and Southeastern Asia, as well as with satellite measurements. The satellite-constrained ammonia emissions represent global concentrations more accurately than state-of-theart emissions. Calculated fluxes in the North China Plain were seen to be more increased after 2015, which is not due to emission changes but due to changes in sulfate emissions that resulted in less ammonia neutralization and hence in larger atmospheric loads. Emissions over Europe were also twice as much as those in traditional datasets with dominant sources being industrial and agricultural applications. Four hot-spot regions of high ammonia emissions were seen in North America, which are characterized by high agricultural activity, such as animal breeding, animal farms and agricultural practices. South America is dominated by ammonia emissions from biomass burning, which causes a strong seasonality. In Southeastern Asia, ammonia emissions from fertilizer plants in China, Pakistan, India and Indonesia are the most important, while a strong seasonality was observed with a spring and late summer peak due to rice and wheat cultivation. Measurements of ammonia surface concentrations were better reproduced with satellite-constrained emissions, such as measurements from CrIS (Cross-track Infrared Sounder)., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2021
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3. Atmospheric ammonia variability and link with particulate matter formation: a case study over the Paris area

Author

C. Viatte, T. Wang, M. Van Damme, E. Dammers, F. Meleux, L. Clarisse, M. W. Shephard, S. Whitburn, P. F. Coheur, K. E. Cady-Pereira, C. Clerbaux, TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (SQUARES), Université libre de Bruxelles (ULB), Environment and Climate Change Canada, Institut National de l'Environnement Industriel et des Risques (INERIS), and Atmospheric and Environmental Research, Inc. (AER)

Subjects
Pollution, Atmospheric Science, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, Atmospheric model, 010501 environmental sciences, Infrared atmospheric sounding interferometer, Atmospheric sciences, 01 natural sciences, lcsh:Chemistry, medicine, Precipitation, 0105 earth and related environmental sciences, media_common, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Particulates, Seasonality, medicine.disease, lcsh:QC1-999, lcsh:QD1-999, 13. Climate action, HYSPLIT, Environmental science, Spatial variability, lcsh:Physics, Sciences exactes et naturelles
Abstract

The Paris megacity experiences frequent particulate matter (i.e.PM2.5, particulate matterwith a diameter less than 2.5 µm) pollution episodes in spring(March–April). At this time of the year, large numbers of the particlesconsist of ammonium sulfate and nitrate which are formed from ammonia(NH3) released during fertilizer spreading practices and transportedfrom the surrounding areas to Paris. There is still limited knowledge of theemission sources around Paris, their magnitude, and their seasonality. Using space-borne NH3 observation records of 10 years (2008–2017) and5 years (2013–2017) provided by the Infrared Atmospheric SoundingInterferometer (IASI) and the Cross-Track Infrared Sounder (CrIS)instrument, regional patterns of NH3 variabilities (seasonal andinterannual) are derived. Observations reveal identical high seasonalvariability with three major NH3 hotspots found from March to August.The high interannual variability is discussed with respect to atmospherictotal precipitation and temperature. A detailed analysis of the seasonal cycle is performed using both IASI andCrIS instrument data, together with outputs from the CHIMERE atmosphericmodel. For 2014 and 2015, the CHIMERE model shows coefficients ofdetermination of 0.58 and 0.18 when compared to IASI and CrIS,respectively. With respect to spatial variability, the CHIMERE monthlyNH3 concentrations in spring show a slight underrepresentation overBelgium and the United Kingdom and an overrepresentation in agricultural areasin the French Brittany–Pays de la Loire and Plateau du Jura region, as wellas in northern Switzerland. In addition, PM2.5 concentrationsderived from the CHIMERE model have been evaluated against surfacemeasurements from the Airparif network over Paris, with which agreement wasfound (r2 = 0.56) with however an underestimation during springpollution events. Using HYSPLIT cluster analysis of back trajectories, we show that NH3total columns measured in spring over Paris are enhanced when air massesoriginate from the north-east (e.g. the Netherlands and Belgium), highlightingthe importance of long-range transport in the NH3 budget over Paris.Variability in NH3 in the north-east region is likely to impact NH3concentrations in the Parisian region since the cross-correlation functionis above 0.3 (at lag = 0 and 1 d). Finally, we quantify the key meteorological parameters driving the specificconditions important for the formation of PM2.5 from NH3 in theÎle-de-France region in spring. Data-driven results based on surfacePM2.5 measurements from the Airparif network and IASI NH3measurements show that a combination of the factors such as a low boundarylayer of ∼500 m, a relatively low temperature of 5 ∘C, a high relative humidity of 70 %, and wind from the north-eastcontributes to a positive PM2.5 and NH3 correlation., info:eu-repo/semantics/published

Published
2020
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4. CMIP5 model selection for ISMIP6 ice sheet model forcing: Greenland and Antarctica

Author

Christopher M. Little, Cécile Agosta, Heiko Goelzer, Sophie Nowicki, Helene Seroussi, Thomas J. Bracegirdle, Fiammetta Straneo, Nicolas C. Jourdain, Tore Hattermann, Alice Barthel, Los Alamos National Laboratory (LANL), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Atmospheric and Environmental Research, Inc. (AER), Norwegian Polar Institute, Institut des Géosciences de l’Environnement (IGE), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institute for Marine and Atmospheric Research [Utrecht] (IMAU), Utrecht University [Utrecht], NASA Goddard Space Flight Center (GSFC), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), ANR-15-CE01-0015,AC-AHC2,Circulation atmosphérique et changement de cycle hydrologique pour l'Arctique(2015), ANR-15-CE01-0005,TROIS-AS,Vers un système de modélisation régionale océan / calotte / atmosphère(2015), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Scripps Institution of Oceanography (SIO - UC San Diego), University of California (UC)-University of California (UC), Sub Dynamics Meteorology, and Marine and Atmospheric Research

Subjects
010504 meteorology & atmospheric sciences, 0207 environmental engineering, Forcing (mathematics), 02 engineering and technology, 010502 geochemistry & geophysics, 01 natural sciences, Atmosphere, 020701 environmental engineering, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, lcsh:Environmental sciences, Water Science and Technology, Earth-Surface Processes, 0105 earth and related environmental sciences, VDP::Mathematics and natural science: 400, lcsh:GE1-350, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, geography, geography.geographical_feature_category, Géologie et minéralogie, Continental shelf, Model selection, lcsh:QE1-996.5, VDP::Technology: 500, VDP::Matematikk og Naturvitenskap: 400, Ice-sheet model, lcsh:Geology, Sea surface temperature, VDP::Teknologi: 500, 13. Climate action, Climatology, Environmental science, Climate model, théorie et applications [Econométrie et méthodes statistiques], Ice sheet
Abstract

The ice sheet model intercomparison project for CMIP6 (ISMIP6) effort brings together the ice sheet and climate modeling communities to gain understanding of the ice sheet contribution to sea level rise. ISMIP6 conducts stand-alone ice sheet experiments that use space- and time-varying forcing derived from atmosphere-ocean coupled global climate models (AOGCMs) to reflect plausible trajectories for climate projections. The goal of this study is to recommend a subset of CMIP5 AOGCMs (three core and three targeted) to produce forcing for ISMIP6 stand-alone ice sheet simulations, based on (i) their representation of current climate near Antarctica and Greenland relative to observations and (ii) their ability to sample a diversity of projected atmosphere and ocean changes over the 21st century. The selection is performed separately for Greenland and Antarctica. Model evaluation over the historical period focuses on variables used to generate ice sheet forcing. For stage (i), we combine metrics of atmosphere and surface ocean state (annual- and seasonal-mean variables over large spatial domains) with metrics of time-mean subsurface ocean temperature biases averaged over sectors of the continental shelf. For stage (ii), we maximize the diversity of climate projections among the best-performing models. Model selection is also constrained by technical limitations, such as availability of required data from RCP2.6 and RCP8.5 projections. The selected top three CMIP5 climate models are CCSM4, MIROC-ESM-CHEM, and NorESM1-M for Antarctica and HadGEM2-ES, MIROC5, and NorESM1-M for Greenland. This model selection was designed specifically for ISMIP6 but can be adapted for other applications., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2020
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5. ATMOSPHERIC GAS ABSORPTION KNOWLEDGE IN THE SUB-MILLIMETER: Modeling, field measurements, and uncertainty quantification

Author

Mario Mech, Viju O. John, Jérôme Vidot, Stuart Fox, Vinia Mattioli, Emma Turner, Carlos De Breuck, Ralf Bennartz, Eli J. Mlawer, Christophe Accadia, Michael Bremer, Tobias Wehr, Alan J. Geer, Alain Smette, Pascal Brunel, Catherine Prigent, Susanne Crewell, Sabatino Di Michele, Maria P. Cadeddu, Domenico Cimini, Frank S. Marzano, Juan R. Pardo, Patrick Eriksson, European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA (UMR_8112)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut für Geophysik und Meteorologie [Köln], Universität zu Köln = University of Cologne, European Centre for Medium-Range Weather Forecasts (ECMWF), Chalmers University of Technology [Göteborg], Wales Institute of Social and Economic Research, Data and Methods (WISERD), Cardiff University, Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Atmospheric and Environmental Research, Inc. (AER), Institut de RadioAstronomie Millimétrique (IRAM), Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory (ESO), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Institute of Methodologies for Environmental Analysis of the National Research Council (IMAA), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), UK Met Office, Centre de Météorologie Spatiale, Direction des Opérations pour la Prévision (DIROP), Météo-France -Météo-France, Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Department of Earth and Environmental Sciences [Nashville], Vanderbilt University [Nashville], United Kingdom Met Office [Exeter], European Organisation for the Exploitation of Meteorological Satellites, Department of Energy (US), Swedish National Space Agency, Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Universität zu Köln, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Consiglio Nazionale delle Ricerche [Roma] (CNR), Météo France, Ecosystèmes littoraux et côtiers (ELICO), Université de Lille, Sciences et Technologies-Université du Littoral Côte d'Opale (ULCO)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), and Ecosystèmes littoraux et côtiers - UMR 8013 (ELICO)

Subjects
Atmospheric Science, Materials science, 010504 meteorology & atmospheric sciences, Field (physics), radiometry, radiative transfer, modeling, 020206 networking & telecommunications, 02 engineering and technology, 01 natural sciences, Computational physics, [SDU]Sciences of the Universe [physics], [SDE]Environmental Sciences, 0202 electrical engineering, electronic engineering, information engineering, Uncertainty quantification, Absorption (electromagnetic radiation), ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

5 pags., 1 fig., descripción no proporcionada por scopus, The workshop was hosted by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), Darmstadt, Germany. Maria Cadeddu is supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research, Atmospheric Radiation Measurement Infrastructure Basic Energy Sciences, under contract DE-AC02-06CH11357. Patrick Ericksson is was supported by the Swedish National Space Agency. Ralf Bennartz was supported by NASA USPI Grant NNX17AJ09G.

Published
2019
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6. Towards Comprehensive Observing and Modeling Systems for Monitoring and Predicting Regional to Coastal Sea Level

Author

Rui M. Ponte, Mark Carson, Mauro Cirano, Catia M. Domingues, Svetlana Jevrejeva, Marta Marcos, Gary Mitchum, R. S. W. van de Wal, Philip L. Woodworth, Michaël Ablain, Fabrice Ardhuin, Valérie Ballu, Mélanie Becker, Jérôme Benveniste, Florence Birol, Elizabeth Bradshaw, Anny Cazenave, P. De Mey-Frémaux, Fabien Durand, Tal Ezer, Lee-Lueng Fu, Ichiro Fukumori, Kathy Gordon, Médéric Gravelle, Stephen M. Griffies, Weiqing Han, Angela Hibbert, Chris W. Hughes, Déborah Idier, Villy H. Kourafalou, Christopher M. Little, Andrew Matthews, Angélique Melet, Mark Merrifield, Benoit Meyssignac, Shoshiro Minobe, Thierry Penduff, Nicolas Picot, Christopher Piecuch, Richard D. Ray, Lesley Rickards, Alvaro Santamaría-Gómez, Detlef Stammer, Joanna Staneva, Laurent Testut, Keith Thompson, Philip Thompson, Stefano Vignudelli, Joanne Williams, Simon D. P. Williams, Guy Wöppelmann, Laure Zanna, Xuebin Zhang, Atmospheric and Environmental Research, Inc. (AER), University of Hamburg, Institute for Marine and Antarctic Studies and Centre for Marine Socioecology, University of Tasmania [Hobart, Australia] (UTAS), National Oceanography Centre [Southampton] (NOC), University of Southampton, Institut Mediterrani d'Estudis Avancats (IMEDEA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Universidad de las Islas Baleares (UIB), Natural Environment Research Council (NERC), Collecte Localisation Satellites (CLS), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National d'Études Spatiales [Toulouse] (CNES), Division Hydrographie Océanographie et Météorologie Militaire (HOM), Service hydrographique et océanographique de la Marine, LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Agence Spatiale Européenne (ESA), European Space Agency (ESA), Echanges Côte-Large (ECOLA), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), Department of Atmospheric and Oceanic Sciences [Boulder] (ATOC), University of Colorado [Boulder], Bangor University, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Centre National d'Études Spatiales [Toulouse] (CNES), Woods Hole Oceanographic Institution (WHOI), Institute of Marine Sciences, Consiglio Nazionale delle Ricerche [Roma] (CNR), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford [Oxford], CSIRO Marine and Atmospheric Research (CSIRO), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Sub Dynamics Meteorology, Marine and Atmospheric Research, LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Agence Spatiale Européenne = European Space Agency (ESA), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), University of Oxford, National Aeronautics and Space Administration (US), Australian Research Council, National Science Foundation (US), Intergovernmental Oceanographic Commission of UNESCO, Natural Environment Research Council (UK), Engineering and Physical Sciences Research Council (UK), Netherlands Organization for Scientific Research, and European Commission

Subjects
0106 biological sciences, coastal impacts, 010504 meteorology & atmospheric sciences, integrated observing system, lcsh:QH1-199.5, coastal, Ocean Engineering, Aquatic Science, Environmental Science (miscellaneous), lcsh:General. Including nature conservation, geographical distribution, Oceanography, 01 natural sciences, Data assimilation, 14. Life underwater, impacts, lcsh:Science, Sea level, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Water Science and Technology, Global and Planetary Change, coastal sea level, business.industry, 010604 marine biology & hydrobiology, Ocean current, Environmental resource management, Geodetic datum, Future sea level, sea-level trends, Current (stream), coastal adaptation, 13. Climate action, observational gaps, coastal ocean modeling, Environmental science, lcsh:Q, Coastal impacts, business, Downscaling
Abstract

A major challenge for managing impacts and implementing effective mitigation measures and adaptation strategies for coastal zones affected by future sea level (SL) rise is our limited capacity to predict SL change at the coast on relevant spatial and temporal scales. Predicting coastal SL requires the ability to monitor and simulate a multitude of physical processes affecting SL, from local effects of wind waves and river runoff to remote influences of the large-scale ocean circulation on the coast. Here we assess our current understanding of the causes of coastal SL variability on monthly to multi-decadal timescales, including geodetic, oceanographic and atmospheric aspects of the problem, and review available observing systems informing on coastal SL. We also review the ability of existing models and data assimilation systems to estimate coastal SL variations and of atmosphere-ocean global coupled models and related regional downscaling efforts to project future SL changes. We discuss (1) observational gaps and uncertainties, and priorities for the development of an optimal and integrated coastal SL observing system, (2) strategies for advancing model capabilities in forecasting short-term processes and projecting long-term changes affecting coastal SL, and (3) possible future developments of sea level services enabling better connection of scientists and user communities and facilitating assessment and decision making for adaptation to future coastal SL change., RP was funded by NASA grant NNH16CT00C. CD was supported by the Australian Research Council (FT130101532 and DP 160103130), the Scientific Committee on Oceanic Research (SCOR) Working Group 148, funded by national SCOR committees and a grant to SCOR from the U.S. National Science Foundation (Grant OCE-1546580), and the Intergovernmental Oceanographic Commission of UNESCO/International Oceanographic Data and Information Exchange (IOC/IODE) IQuOD Steering Group. SJ was supported by the Natural Environmental Research Council under Grant Agreement No. NE/P01517/1 and by the EPSRC NEWTON Fund Sustainable Deltas Programme, Grant Number EP/R024537/1. RvdW received funding from NWO, Grant 866.13.001. WH was supported by NASA (NNX17AI63G and NNX17AH25G). CL was supported by NASA Grant NNH16CT01C. This work is a contribution to the PIRATE project funded by CNES (to TP). PT was supported by the NOAA Research Global Ocean Monitoring and Observing Program through its sponsorship of UHSLC (NA16NMF4320058). JS was supported by EU contract 730030 (call H2020-EO-2016, “CEASELESS”). JW was supported by EU Horizon 2020 Grant 633211, Atlantos.

Published
2019
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7. Concepts and Terminology for Sea Level: Mean, Variability and Change, Both Local and Global

Author

Natalya Gomez, Mark E. Tamisiea, Detlef Stammer, Rui M. Ponte, Roderik S. W. van de Wal, Jason Lowe, John A. Church, Stephen M. Griffies, Robert E. Kopp, Chris W. Hughes, Gonéri Le Cozannet, Felix W. Landerer, Ichiro Fukimori, Jonathan M. Gregory, National Centre for Atmospheric Science, University of Reading, Reading, United Kingdom, NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), Bangor University, Met Office Hadley Centre for Climate Change (MOHC), United Kingdom Met Office [Exeter], University of New South Wales [Sydney] (UNSW), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), McGill University = Université McGill [Montréal, Canada], Rutgers University [Camden], Rutgers University System (Rutgers), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Atmospheric and Environmental Research, Inc. (AER), University of Hamburg, Center for Space Research [Austin] (CSR), University of Texas at Austin [Austin], University of Leeds, Sub Dynamics Meteorology, and Marine and Atmospheric Research

Subjects
History, 010504 meteorology & atmospheric sciences, media_common.quotation_subject, Global warming, Subject (philosophy), Public policy, Climate change, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Ambiguity, 010502 geochemistry & geophysics, Terminology, 01 natural sciences, Epistemology, Geophysics, 13. Climate action, Order (exchange), Geochemistry and Petrology, Sea level, 14. Life underwater, 0105 earth and related environmental sciences, media_common, Concepts
Abstract

International audience; Changes in sea level lead to some of the most severe impacts of anthropogenic climate change. Consequently, they are a subject of great interest in both scientific research and public policy. This paper defines concepts and terminology associated with sea level and sea-level changes in order to facilitate progress in sea-level science, in which communication is sometimes hindered by inconsistent and unclear language. We identify key terms and clarify their physical and mathematical meanings, make links between concepts and across disciplines, draw distinctions where there is ambiguity, and propose new terminology where it is lacking or where existing terminology is confusing. We include for-mulae and diagrams to support the definitions.

Published
2019
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8. Comparison of SMOS and SMAP soil moisture retrieval approaches using tower-based radiometer data over a vineyard field

Author

Ernesto Lopez-Baeza, Yann Kerr, Peggy O'Neill, Ahmad Al Bitar, P. Richaume, Heather Lawrence, Roberto Fernandez Moran, Gabrielle De Lannoy, Jean-Pierre Wigneron, Richard de Jeu, Arnaud Mialon, Simone Bircher, Mike Schwank, Thomas J. Jackson, Maciej Miernecki, University of Hamburg, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Universitat de València (UV), Centre d'études spatiales de la biosphère (CESBIO), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Vrije universiteit = Free university of Amsterdam [Amsterdam] (VU), Atmospheric and Environmental Research, Inc. (AER), Hydrology and Remote Sensing Laboratory, US Department of Agriculture [Beltsville] (USDA), Gamma Remote Sensing, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, European Centre for Medium-Range Weather Forecasts (ECMWF), VU University Amsterdam, Earth and Climate, and Amsterdam Global Change Institute

Subjects
010504 meteorology & atmospheric sciences, Mean squared error, Meteorology, [SDE.MCG]Environmental Sciences/Global Changes, 0211 other engineering and technologies, Soil Science, 02 engineering and technology, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Physics::Geophysics, 14. Life underwater, Computers in Earth Sciences, Time series, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Atmospheric sounding, Valencia Anchor Station, Radiometer, Geology, Inversion (meteorology), SMAP, 15. Life on land, Brightness temperature, Soil water, Environmental science, Radiometry, Soil moisture retrieval, ELBARA, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, SMOS
Abstract

International audience; The objective of this study was to compare several approaches to soil moisture (SM) retrieval using l-band microwave radiometry. The comparison was based on a brightness temperature (TB) data set acquired since 2010 by the L-band radiometer ELBARA-II over a vineyard field at the Valencia Anchor Station (VAS) site. ELBARA-II, provided by the European Space Agency (ESA) within the scientific program of the SMOS (Soil Moisture and Ocean Salinity) mission, measures multiangular TB data at horizontal and vertical polarization for a range of incidence angles (30°–60°). Based on a three year data set (2010–2012), several SM retrieval approaches developed for spaceborne missions including AMSR-E (Advanced Microwave Scanning Radiometer for EOS), SMAP (Soil Moisture Active Passive) and SMOS were compared. The approaches include: the Single Channel Algorithm (SCA) for horizontal (SCA-H) and vertical (SCA-V) polarizations, the Dual Channel Algorithm (DCA), the Land Parameter Retrieval Model (LPRM) and two simplified approaches based on statistical regressions (referred to as ‘Mattar’ and ‘Saleh’). Time series of vegetation indices required for three of the algorithms (SCA-H, SCA-V and ‘Mattar’) were obtained from MODIS observations. The SM retrievals were evaluated against reference SM values estimated from a multiangular 2-Parameter inversion approach. As no in situ SM data was used, the evaluation made here is relative to the use of this specific reference data set. The results obtained with the current base line algorithms developed for SMAP (SCA-H and -V) are in very good agreement with the ‘reference’ SM data set derived from the multi-angular observations (R2 ≈ 0.90, RMSE varying between 0.035 and 0.056 m3/m3 for several retrieval configurations). This result showed that, provided the relationship between vegetation optical depth and a remotely-sensed vegetation index can be calibrated, the SCA algorithms can provide results very close to those obtained from multi-angular observations in this study area. The approaches based on statistical regressions provided similar results and the best accuracy was obtained with the ‘Saleh’ methods based on either bi-angular or bipolarization observations (R2 ≈ 0.93, RMSE ≈ 0.035 m3/m3). The LPRM and DCA algorithms were found to be slightly less successful in retrieving the ‘reference’ SM time series (R2 ≈ 0.75, RMSE ≈ 0.055 m3/m3). However, the two above approaches have the great advantage of not requiring any model calibrations previous to the SM retrievals.

Published
2014
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9. Satellite and In Situ Salinity: Understanding Near-Surface Stratification and Subfootprint Variability

Author

Ludovic Brucker, Andrea Santos-Garcia, Tong Lee, Jacqueline Boutin, Alexander Soloviev, Emmanuel P. Dinnat, Brian Ward, Wenqing Tang, Nicolas Reul, William E. Asher, Nadya T. Vinogradova, Nicolas Kolodziejczyk, Julian Schanze, Kyla Drushka, Jessica Anderson, Thomas Meissner, Yi Chao, Christophe Maes, Thierry Delcroix, W.L. Jones, R. Drucker, Lisan Yu, Gilles Reverdin, Interactions et Processus au sein de la couche de Surface Océanique (IPSO), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), UCLA Joint Institute for Regional Earth System Science and Engineering (JIFRESSE), University of California [Los Angeles] (UCLA), University of California-University of California-NASA, Remote Sensing Solutions, University of Washington [Seattle], Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), School of Oceanography [Seattle], Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Ifremer, Centre de Toulon, Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Earth and Space Research Institute [Seattle] (ESR), Nova Southeastern University (NSU), Woods Hole Oceanographic Institution (WHOI), Universities Space Research Association (USRA), GSFC Cryospheric Sciences Laboratory, NASA Goddard Space Flight Center (GSFC), Electrical and Computer Engineering Department [Orlando], University of Central Florida [Orlando] (UCF), Laboratoire de physique des océans (LPO), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Remote Sensing Systems [Santa Rosa] (RSS), Atmospheric and Environmental Research, Inc. (AER), National University of Ireland [Galway] (NUI Galway), CNES, Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), University of California (UC)-University of California (UC)-NASA, Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, 0211 other engineering and technologies, Mesoscale meteorology, Stratification (water), 02 engineering and technology, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, Atmospheric sciences, 01 natural sciences, western equatorial pacific, barrier layer, tropical oceans, north-atlantic, ocean salinity, 14. Life underwater, Water cycle, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Radiometer, boundary-layer, pacific warm pool, Salinity, Ocean dynamics, band radiometer/scatterometer observations, 13. Climate action, polar-regions, air-sea interaction, Environmental science, Satellite, Microwave
Abstract

Remote sensing of salinity using satellite-mounted microwave radiometers provides new perspectives for studying ocean dynamics and the global hydrological cycle. Calibration and validation of these measurements is challenging because satellite and in situ methods measure salinity differently. Microwave radiometers measure the salinity in the top few centimeters of the ocean, whereas most in situ observations are reported below a depth of a few meters. Additionally, satellites measure salinity as a spatial average over an area of about 100 × 100 km2. In contrast, in situ sensors provide pointwise measurements at the location of the sensor. Thus, the presence of vertical gradients in, and horizontal variability of, sea surface salinity complicates comparison of satellite and in situ measurements. This paper synthesizes present knowledge of the magnitude and the processes that contribute to the formation and evolution of vertical and horizontal variability in near-surface salinity. Rainfall, freshwater plumes, and evaporation can generate vertical gradients of salinity, and in some cases these gradients can be large enough to affect validation of satellite measurements. Similarly, mesoscale to submesoscale processes can lead to horizontal variability that can also affect comparisons of satellite data to in situ data. Comparisons between satellite and in situ salinity measurements must take into account both vertical stratification and horizontal variability.

Published
2016
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10. Using First- and Second-Order Variograms for Characterizing Landscape Spatial Structures From Remote Sensing Imagery

Author

Denis Allard, Frédéric Baret, Sébastien Garrigues, Atmospheric and Environmental Research, Inc. (AER), Biostatistique et Processus Spatiaux (BioSP), Institut National de la Recherche Agronomique (INRA), Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), and Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
010504 meteorology & atmospheric sciences, Stochastic modelling, STOCHASTIC SIMULATION, télédétection, géostatistique, variogramme, 0211 other engineering and technologies, modélisation spatiale, Image processing, 02 engineering and technology, Geostatistics, POISSON LINE MOSAIC MODEL, 01 natural sciences, Normalized Difference Vegetation Index, REMOTE SENSING, VARIOGRAM, LANDSCAPE STRUCTURE, MULTI-GAUSSIAN MODEL, Ingénierie assistée par ordinateur, paysage, Electrical and Electronic Engineering, végétation, Variogram, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Vegetation, [INFO.INFO-IA]Computer Science [cs]/Computer Aided Engineering, 15. Life on land, Computer Aided Engineering, General Earth and Planetary Sciences, Spatial variability, Scale (map), Geology, simulation stochastique
Abstract

International audience; The spatial structures displayed by remote sensing imagery are essential information characterizing the nature and the scale of spatial variation of Earth surface processes. This paper provides a new approach to characterize the spatial structures within remote sensing imagery using stochastic models an geostatistic metrics. Up to now, the second-order variogram has been widely used to describe the spatial variations within an image. In this paper, we demonstrate its limitation to discriminate distinct image spatial structures. We introduce a different geostatistic metric, the first-order variogram, which used in combination with the second-order variogram, will prove its efficiency to describe the image spatial structures. We then develop a method based on the simultaneous use of both first- and second-order variogram metrics to model the image spatial structures as the weighted linear combination of two stochastic models: a Poisson line mosaic model and a multi-Gaussian model. The image spatial structures are characterized by the variance weight and the variogram range related to each model. This method is applied to several SPOT-HRV Normalized Difference Vegetation Index (NDVI) images from the VALERI database in order to characterize the nature of the processes structuring different types of landscape. The mosaic model is an indicator of strong NDVI discontinuities within the image mainly generated by anthropogenic processes such as the mosaic pattern of crop sites. The multi-Gaussian model shows, evidence of diffuse and continuous variation of NDVI generally engendered by ecological and environmental processes such as the fuzzy pattern observed over forest and natural vegetation sites.

Published
2007
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11. Green leaf area and fraction of photosynthetically active radiation absorbed by vegetation

Author

Ranga B. Myneni, Marie Weiss, Sanmay Ganguly, G. Zhang, Hirofumi Hashimoto, Kumaresh Singh, Cristina Milesi, Jian Bi, Ramakrishna R. Nemani, Frédéric Baret, Aleixandre Verger, Arindam Samanta, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Osaka University [Osaka], Universität Heidelberg [Heidelberg], Department of Earth and Environment, Boston University, Boston, MA 02215, United States, affiliation inconnue, Bay Area Environmental Research Institute (BAER), NASA Advanced Supercomputing Division (NAS), NASA, Department of Earth and Environment [Boston], Boston University [Boston] (BU), Department of Science and Environmental Policy [Monterey Bay], California State University [Monterey Bay] (CSUMB), Atmospheric and Environmental Research, Inc. (AER), Risk Management Solutions, and Jonathan Hanes

Subjects
Accuracy and precision, 010504 meteorology & atmospheric sciences, Pixel, Advanced very-high-resolution radiometer, [SDE.MCG]Environmental Sciences/Global Changes, 04 agricultural and veterinary sciences, Vegetation, 15. Life on land, 01 natural sciences, Green leaf, Geography, 13. Climate action, Photosynthetically active radiation, [SDU]Sciences of the Universe [physics], 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Moderate-resolution imaging spectroradiometer, Leaf area index, 0105 earth and related environmental sciences, Remote sensing
Abstract

International audience; Leaf Area Index (LAI), the area of leaves per unit ground area, and the Fraction of Photosynthetically Active Radiation (FPAR; 400–700 nm) absorbed by vegetation are important biophysical variables for quantifying the cycling of water, carbon and nutrients through ecosystems. The LAI/FPAR products from the Advanced Very High Resolution Radiometer (AVHRR), the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor and the Système Pour l’Observation de la Terre (SPOT) sensor have a large Earth science community user base and the ease of access, provision of pixel quality and validation information have greatly aided the use of these products. Recent research efforts focusing on inter-sensor product consistencies have developed a foundation upon which mature algorithms and a validation framework can act synergistically to further refine the accuracy and precision of these existing long-term products. This chapter provides a brief overview of the recent progresses in LAI/FPAR estimation algorithms and resulting biophysical products from the AVHRR, MODIS, SPOT and Landsat data

Published
2013
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12. Tropospheric methanol observations from space: retrieval evaluation and constraints on the seasonality of biogenic emissions

Author

Allen H. Goldstein, Lu Hu, Lieven Clarisse, Hanwant B. Singh, Carsten Warneke, Mark W. Shephard, Y. Xiao, Eric C. Apel, Barkley C. Sive, J. A. de Gouw, Cathy Clerbaux, Dylan B. Millet, Kelley C. Wells, Karen Cady-Pereira, Pierre-François Coheur, Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Atmospheric and Environmental Research, Inc. (AER), Environment and Climate Change Canada, Atmospheric and Climate Applications, Inc. (ACApps), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Atmospheric Chemistry Division [Boulder], National Center for Atmospheric Research [Boulder] (NCAR), NOAA Earth System Research Laboratory (ESRL), National Oceanic and Atmospheric Administration (NOAA), Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado [Boulder]-National Oceanic and Atmospheric Administration (NOAA), NASA Ames Research Center (ARC), Department of Environmental Science, Policy, and Management [Berkeley] (ESPM), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Appalachian State University, University of North Carolina System (UNC), University of California [Berkeley], and University of California-University of California

Subjects
Atmospheric Science, Chemical transport model, 010504 meteorology & atmospheric sciences, Télédétection, [SDE.MCG]Environmental Sciences/Global Changes, 010501 environmental sciences, Infrared atmospheric sounding interferometer, Atmospheric sciences, 010502 geochemistry & geophysics, 01 natural sciences, Article, Troposphere, lcsh:Chemistry, Phénomènes atmosphériques, medicine, Leaf area index, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Seasonality, 15. Life on land, medicine.disease, lcsh:QC1-999, Trace gas, Sciences de la terre et du cosmos, Tropospheric Emission Spectrometer, lcsh:QD1-999, 13. Climate action, Environmental science, Satellite, lcsh:Physics
Abstract

Methanol retrievals from nadir-viewing space-based sensors offer powerful new information for quantifying methanol emissions on a global scale. Here we apply an ensemble of aircraft observations over North America to evaluate new methanol measurements from the Tropospheric Emission Spectrometer (TES) on the Aura satellite, and combine the TES data with observations from the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp-A satellite to investigate the seasonality of methanol emissions from northern midlatitude ecosystems. Using the GEOS-Chem chemical transport model as an intercomparison platform, we find that the TES retrieval performs well when the degrees of freedom for signal (DOFS) are above 0.5, in which case the model:TES regressions are generally consistent with the model:aircraft comparisons. Including retrievals with DOFS below 0.5 degrades the comparisons, as these are excessively influenced by the a priori. The comparisons suggest DOFS >0.5 as a minimum threshold for interpreting retrievals of trace gases with a weak tropospheric signal. We analyze one full year of satellite observations and find that GEOS-Chem, driven with MEGANv2.1 biogenic emissions, underestimates observed methanol concentrations throughout the midlatitudes in springtime, with the timing of the seasonal peak in model emissions 1-2 months too late. We attribute this discrepancy to an underestimate of emissions from new leaves in MEGAN, and apply the satellite data to better quantify the seasonal change in methanol emissions for midlatitude ecosystems. The derived parameters (relative emission factors of 11.0, 0.26, 0.12 and 3.0 for new, growing, mature, and old leaves, respectively, plus a leaf area index activity factor of 0.5 for expanding canopies with leaf area index, SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2012
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13. Satellite monitoring of ammonia: A case study of the San Joaquin Valley

Author

Cathy Clerbaux, Mark W. Shephard, Karen Cady-Pereira, Franck Dentener, Lieven Clarisse, Martin Van Damme, Federico Karagulian, Daniel Hurtmans, Pierre-François Coheur, Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Atmospheric and Environmental Research, Inc. (AER), JRC Institute for Environment and Sustainability (IES), European Commission - Joint Research Centre [Ispra] (JRC), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, Soil Science, 010501 environmental sciences, Aquatic Science, Infrared atmospheric sounding interferometer, Oceanography, Atmospheric sciences, 01 natural sciences, Atmosphere, Troposphere, Altitude, Geochemistry and Petrology, Ammonia, Earth and Planetary Sciences (miscellaneous), Inversion temperature, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Ecology, Paleontology, Forestry, Remote sensing, Depth sounding, Geophysics, Tropospheric Emission Spectrometer, 13. Climate action, Space and Planetary Science, Environmental science, San Joaquin, Infrared
Abstract

International audience; Atmospheric ammonia (NH3) has recently been observed with infrared sounders from space. Here we present 1 year of detailed bidaily satellite retrievals with the Infrared Atmospheric Sounding Interferometer and some retrievals of the Tropospheric Emission Spectrometer over the San Joaquin Valley, California, a highly polluted agricultural production region. Several sensitivity issues are discussed related to the sounding of ammonia, in terms of degrees of freedom, averaging kernels, and altitude of maximum sensitivity and in relation to thermal contrast and concentration. We also discuss their seasonal dependence and sources of errors. We demonstrate boundary layer sensitivity of infrared sounders when there is a large thermal contrast between the surface and the bottom of the atmosphere. For the San Joaquin Valley, large thermal contrast is the case for daytime measurements in spring, summer, and autumn and for nighttime measurements in autumn and winter when a large negative thermal contrast is amplified by temperature inversion.

Published
2010
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14. Validation of version-4.61 methane and nitrous oxide observed by MIPAS

Author

Payan, Camy-Peyret, Oelhaf, Wetzel, Maucher, Keim, Pirre, Huret, Engel, Volk, M. C., Kuellmann, Kuttippurath, Cortesi, Bianchini, Mencaraglia, Raspollini, Redaelli, Vigouroux, De Mazière, Mikuteit, Blumenstock, Velazco, Notholt, Mahieu, Duchatelet, Smale, Wood, Jones, Piccolo, Payne, Bracher, Glatthor, Stiller, Grunow, Jeseck, Butz, Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique (LPMAA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut für Meteorologie und Klimaforschung (IMK), Karlsruher Institut für Technologie (KIT), Laboratoire de physique et chimie de l'environnement (LPCE), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Atmosphäre und Umwelt [Frankfurt/Main] (IAU), Goethe-Universität Frankfurt am Main, Institute of Environmental Physics and Remote Sensing [Bremen] (IUP/IFE), University of Bremen, Istituto di Fisica Applicata 'Nello Carrara' (IFAC), Consiglio Nazionale delle Ricerche [Roma] (CNR), Dipartimento di Fisica [L'Aquila], Università degli Studi dell'Aquila [L'Aquila] (UNIVAQ.IT), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, National Institute of Water and Atmospheric Research [Lauder] (NIWA), University of Wollongong, Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford [Oxford], Atmospheric and Environmental Research, Inc. (AER), Freie Universität Berlin, Institut für Umweltphysik [Heidelberg], Universität Heidelberg [Heidelberg], Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), University of Wollongong [Australia], University of Oxford, Universität Heidelberg [Heidelberg] = Heidelberg University, and Università degli Studi dell'Aquila (UNIVAQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Atmospheric Science, Nitrous oxide, 010504 meteorology & atmospheric sciences, Meteorology, Chemistry, 01 natural sciences, lcsh:QC1-999, 010305 fluids & plasmas, SCIAMACHY, Troposphere, lcsh:Chemistry, Earth sciences, remote sensing, Atmospheric composition and structure, lcsh:QD1-999, 13. Climate action, 0103 physical sciences, ddc:550, Positive bias, Methane, Stratosphere, lcsh:Physics, 0105 earth and related environmental sciences, Remote sensing
Abstract

The ENVISAT validation programme for the atmospheric instruments MIPAS, SCIAMACHY and GOMOS is based on a number of balloon-borne, aircraft, satellite and ground-based correlative measurements. In particular the activities of validation scientists were coordinated by ESA within the ENVISAT Stratospheric Aircraft and Balloon Campaign or ESABC. As part of a series of similar papers on other species [this issue] and in parallel to the contribution of the individual validation teams, the present paper provides a synthesis of comparisons performed between MIPAS CH4 and N2O profiles produced by the current ESA operational software (Instrument Processing Facility version 4.61 or IPF v4.61, full resolution MIPAS data covering the period 9 July 2002 to 26 March 2004) and correlative measurements obtained from balloon and aircraft experiments as well as from satellite sensors or from ground-based instruments. In the middle stratosphere, no significant bias is observed between MIPAS and correlative measurements, and MIPAS is providing a very consistent and global picture of the distribution of CH4 and N2O in this region. In average, the MIPAS CH4 values show a small positive bias in the lower stratosphere of about 5%. A similar situation is observed for N2O with a positive bias of 4%. In the lower stratosphere/upper troposphere (UT/LS) the individual used MIPAS data version 4.61 still exhibits some unphysical oscillations in individual CH4 and N2O profiles caused by the processing algorithm (with almost no regularization). Taking these problems into account, the MIPAS CH4 and N2O profiles are behaving as expected from the internal error estimation of IPF v4.61 and the estimated errors of the correlative measurements.

Published
2009
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15. Regional modeling of carbonaceous aerosols over Europe—focus on secondary organic aerosols

Author

Sophie Moukhtar, Catherine Liousse, Bertrand Bessagnet, Christian Seigneur, Michael Schulz, B. Guillaume, Betty K. Pun, Laurent Menut, Alma Hodzic, Gabriele Curci, Institut National de l'Environnement Industriel et des Risques (INERIS), Institut Pierre-Simon-Laplace (IPSL), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Centre of Excellence CETEMPS, Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ), National Center for Atmospheric Research [Boulder] (NCAR), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Centre for Atmospheric Chemistry [Toronto], York University [Toronto], Atmospheric and Environmental Research, Inc. (AER), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National d'Études Spatiales [Toulouse] (CNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Università degli Studi dell'Aquila (UNIVAQ), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, Isoprene, Air pollution, Secondary organic aerosols, 010501 environmental sciences, medicine.disease_cause, Atmospheric sciences, 01 natural sciences, Mediterranean Basin, behavioral disciplines and activities, chemistry.chemical_compound, medicine, Environmental Chemistry, Organic carbon, 0105 earth and related environmental sciences, Total organic carbon, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Modeling, Particulates, Aerosol, chemistry, 13. Climate action, Atmospheric chemistry, Monoterpenes, Elemental carbon
Abstract

International audience; In this study, an improved and complete secondary organic aerosols (SOA) chemistry scheme was implemented in the CHIMERE model. The implementation of isoprene chemistry for SOA significantly improves agreement between long series of simulated and observed particulate matter concentrations. While simulated organic carbon concentrations are clearly improved at elevated sites by adding the SOA scheme, time correlation are impaired at low level sites in Portugal, Italy and Slovakia. At several sites a clear underestimation by the CHIMERE model is noticed in wintertime possibly due to missing wood burning emissions as shown in previous modeling studies. In Europe, the CHIMERE model gives yearly average SOA concentrations ranging from 0.5μg/m3 in the Northern Europe to 4μg/m3 over forested regions in Spain, France, Germany and Italy. In addition, our work suggests that during the highest fire emission periods, fires can be the dominant source of primary organic carbon over the Mediterranean Basin, but the SOA contribution from fire emissions is low. Isoprene chemistry has a strong impact on SOA formation when using current available kinetic schemes.

Published
2009
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16. Multivariate quantification of landscape spatial heterogeneity using variogram models

Author

Jeffrey T. Morisette, Denis Allard, Sébastien Garrigues, Frédéric Baret, Atmospheric and Environmental Research, Inc. (AER), Biostatistique et Processus Spatiaux (BioSP), Institut National de la Recherche Agronomique (INRA), Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), and Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)

Subjects
[SPI.OTHER]Engineering Sciences [physics]/Other, Spatial correlation, VARIOGRAM, MULTIVARIATE VARIOGRAM MODEL, STATIONARITY, DIGITAL IMAGE, LANDSCAPE STRUCTURE, RED AND NEAR INFRARED, SPATIAL HETEROGENEITY, LINEAR MODEL, LENGTH SCALE, SPATIAL STRUCTURE, MODERATE SPATIAL RESOLUTION, NDVI, 010504 meteorology & atmospheric sciences, télédétection, variogramme, 0211 other engineering and technologies, Soil Science, modélisation spatiale, 02 engineering and technology, Astrophysics::Cosmology and Extragalactic Astrophysics, hétérogénéité spatiale, 01 natural sciences, Normalized Difference Vegetation Index, lumière rouge et infra rouge, modèle linéaire, paysage, Computers in Earth Sciences, végétation, Variogram, Astrophysics::Galaxy Astrophysics, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Geology, Vegetation, Spectral bands, 15. Life on land, Spatial heterogeneity, échelle, Autre (Sciences de l'ingénieur), image numérique, Environmental science, Spatial variability, Scale (map)
Abstract

International audience; The monitoring of earth surface processes at a global scale requires high temporal frequency remote sensing observations provided up to now by moderate spatial resolution sensors (from 250 m to 7 kin). Non-linear estimation processes of land surface variables derived from remote sensing data can be biased by the surface spatial heterogeneity within the moderate spatial resolution pixel. Quantifying this surface spatial heterogeneity is thus required to correct non-linear estimation processes of land surface variables. The first step in this process is to properly characterize the scale of spatial variation of the processes structuring the landscape. Since the description of land surface processes generally involves various spectral bands, a multivariate approach to characterize the surface spatial heterogeneity from multi-spectral remote sensing observations has to be established. This work aims at quantifying the landscape spatial heterogeneity captured by red and near infrared high spatial resolution images using direct and cross-variograms modeled together with the geostatistical linear model of coregionalization. This model quantifies the overall spatial variability and correlation of red and near infrared reflectances over the scene. In addition, it provides an explicit understanding of the landscape spatial structures captured by red and near infrared reflectances and is thus appropriate to describe landscapes composed of areas with contrasted red and near infrared spectral properties. The application of the linear model of coregionalization to 18 contrasted landscapes provides a spatial signature of red and near infrared spectral properties characterizing each type of landscape. Low vegetation cover sites are characterized by positive spatial correlation between red and near infrared. The mosaic pattern of vegetation fields and bare soil fields over crop sites generates high and negative spatial correlation between red and near infrared and increases the spatial variability of red and near infrared. On forest sites, the important amount of vegetation limits the spatial variability of red and the shadow effects mainly captured by near infrared induce a low and positive spatial correlation between red and near infrared. Finally, the linear model of coregionalization applied to red and near infrared is shown to be more powerful than the univariate variogram modeling applied to NDVI because the second order stationarity hypothesis on which variogram modeling relies is more frequently verified for red and near infrared than for NDVI.

Published
2008
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17. Validation and data characteristics of methane and nitrous oxide profiles observed by MIPAS and processed with Version 4.61 algorithm

Author

Payan, Camy-Peyret, Oelhaf, Wetzel, Maucher, Keim, Pirre, Huret, Engel, Volk, M. C., Kuellmann, Kuttippurath, Cortesi, Bianchini, Mencaraglia, Raspollini, Redaelli, Vigouroux, De Mazière, Mikuteit, Blumenstock, Velazco, Notholt, Mahieu, Duchatelet, Smale, Wood, Jones, Piccolo, Payne, Bracher, Glatthor, Stiller, Grunow, Jeseck, Pfeilsticker, Butz, A, Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique (LPMAA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut für Meteorologie und Klimaforschung (IMK), Karlsruher Institut für Technologie (KIT), Laboratoire de physique et chimie de l'environnement (LPCE), Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Atmosphäre und Umwelt [Frankfurt/Main] (IAU), Goethe-Universität Frankfurt am Main, Remote Sensing Department [Bremen] (IFE), Institute of Environmental Physics [Bremen] (IUP), University of Bremen-University of Bremen, Istituto di Fisica Applicata 'Nello Carrara' (IFAC), Consiglio Nazionale delle Ricerche [Roma] (CNR), University of L'Aquila [Italy] (UNIVAQ), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, National Institute of Water and Atmospheric Research [Lauder] (NIWA), University of Wollongong, Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford [Oxford], Atmospheric and Environmental Research, Inc. (AER), Institut für Meteorologie [Berlin], Freie Universität Berlin, Institut für Umweltphysik [Heidelberg], Universität Heidelberg [Heidelberg], Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), University of Wollongong [Australia], Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), University of Oxford, Universität Heidelberg [Heidelberg] = Heidelberg University, Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique ( LPMAA ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Institut für Meteorologie und Klimaforschung ( IMK ), Karlsruher Institut für Technologie ( KIT ), Laboratoire de physique et chimie de l'environnement ( LPCE ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université d'Orléans ( UO ) -Centre National de la Recherche Scientifique ( CNRS ), Institut für Atmosphäre und Umwelt [Frankfurt/Main] ( IAU ), Institute of Remote Sensing [Bremen] ( IFE ), Institute of Environmental Physics [Bremen] ( IUP ), Istituto di Fisica Applicata 'Nello Carrara' ( IFAC ), Consiglio Nazionale delle Ricerche [Roma] ( CNR ), University of L'Aquila [Italy] ( UNIVAQ ), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique ( BIRA-IASB ), National Institute of Water and Atmospheric Research [Lauder] ( NIWA ), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] ( AOPP ), Atmospheric and Environmental Research, Atmospheric and Environment Research ( AER ), and Freie Universität Berlin [Berlin]

Subjects
[ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Nitrous oxide, 010504 meteorology & atmospheric sciences, Meteorology, Systematic deviation, Remote sensing, 01 natural sciences, Methane, SCIAMACHY, 010309 optics, chemistry.chemical_compound, Atmospheric composition and structure, chemistry, 13. Climate action, 0103 physical sciences, Satellite, Positive bias, Algorithm, Stratosphere, 0105 earth and related environmental sciences
Abstract

International audience; The ENVISAT validation programme for the atmospheric instruments MIPAS, SCIAMACHY and GOMOS is based on a number of balloon-bone, aircraft and ground-based correlative measurements. In particular the activities of validation scientists were coordinated by ESA within the ENVISAT Stratospheric Aircraft and Balloon Campaign of ESABC. As part of a series of similar papers on other species [this issue] and in parallel to the contribution of the individual validation teams, the present paper provides a synthesis of comparisons performed between MIPAS CH4 and N2O profiles produced by the current ESA operational software (Instrument Processing Facility version 4.61 or IPF v4.61) and correlative measurements obtained from balloon and aircraft experiments as well as from satellite sensors or from ground-based instruments. The MIPAS-E CH4 values show a positive bias in the lower stratosphere of about 10%. In case of N2O no systematic deviation with respect to the validation experiments could be identified. The individual used MIPAS data version 4.61 still exhibits some unphysical oscillations in individual CH4 and N2O profiles caused by the processing algorithm (with almost no regularization). Taking these problems into account, the MIPAS CH4 and N2O profiles are behaving as expected from the internal error estimation of IPF v4.61.

Published
2007
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18. Validation of NO2 and HNO3 measurements from the Improved Limb Atmospheric Spectrometer (ILAS) with the version 5.20 retrieval algorithm

Author

David G. Johnson, Kenneth W. Jucks, Hermann Oelhaf, Takakiyo Nakazawa, Farahnaz Khosrawi, Yasuhiro Sasano, Gerald Wetzel, Shuji Aoki, Hitoshi Irie, Hiroshi Kanzawa, Bhaswar Sen, G. C. Toon, Hideaki Nakajima, Rolf Müller, Andreas Engel, Wesley A. Traub, Tatsuya Yokota, Takafumi Sugita, Solar-Terrestrial Environment Laboratory [Nagoya] (STEL), Nagoya University, Research Center for Advanced Science and Technology [Tokyo] (RCAST), The University of Tokyo (UTokyo), Department of Earth and Planetary Sciences [TITECH Tokyo], Tokyo Institute of Technology [Tokyo] (TITECH), Atmospheric and Environmental Research, Inc. (AER), Laboratoire de Physique moléculaire et applications (LPMA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute for Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology (KIT), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Naval Research Laboratory (NRL), NASA Langley Research Center [Hampton] (LaRC), Laboratoire de physique et chimie de l'environnement (LPCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), National Institute for Environmental Studies (NIES), and Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, Instrumentation, Soil Science, Aquatic Science, Oceanography, 01 natural sciences, 010305 fluids & plasmas, Altitude, Geochemistry and Petrology, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Stratosphere, Retrieval algorithm, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, Remote sensing, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Ecology, Spectrometer, Northern Hemisphere, Paleontology, Forestry, On board, Geophysics, 13. Climate action, Space and Planetary Science, Environmental science, Satellite
Abstract

[1] Measurements of CFC-12 were made by the Improved Limb Atmospheric Spectrometer (ILAS) between 57°N and 72°N in the Northern Hemisphere and between 64°S and 89°S in the Southern Hemisphere. ILAS was launched on 17 August 1996 on board the Advanced Earth Observing Satellite (ADEOS). The ILAS validation balloon campaigns were carried out from Kiruna, Sweden (68°N, 21°E), in February and March 1997 and from Fairbanks, Alaska (65°N, 148°W), in April and May 1997. During these validation balloon campaigns, CFC-12 was measured with the in situ instruments ASTRID, BONBON, and SAKURA and the remote sensing spectrometers MIPAS-B, FIRS-2, and MkIV. ILAS version 6.0 CFC-12 profiles obtained at the nearest location to the validation balloon measurement are compared with these validation balloon measurements. The quality of ILAS CFC-12 data processed with the version 6.0 algorithm improved significantly compared to previous versions. Low relative differences between ILAS CFC-12 and the correlative measurements of about 10% were found between 13 and 20 km. The comparison of vertical profiles shows that ILAS CFC-12 data are useful below about 20–22 km inside the vortex and below about 25 km outside the vortex. However, at greater altitudes the relative percentage difference increases very strongly with increasing altitude. Further, correlations of CFC-12 with N2O show a good agreement with the correlative measurements for N2O values of N2O > 150 ppbv. In summary, ILAS CFC-12 data are now suitable for scientific studies in the lower stratosphere.

Published
2002
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19. Evaluation and intercomparison of global atmospheric transport models using 222Rn and other short‐lived tracers

Author

Run-Lie Shia, Gé Verver, Johann Feichter, K. S. Law, S. R. Beagley, Peter H. Zimmermann, Margaret Brown, Yves Balkanski, Philip J. Rasch, D. A. Rotman, Oliver Wild, I. Köhler, William L. Grose, Christophe Genthon, Hu Yang, Jane Dignon, Michel Ramonet, Michael J. Prather, Masaru Chiba, Prasad S. Kasibhatla, J. de Grandpré, Daniel Bergmann, Daniel J. Jacob, Peter van Velthoven, Mark A. Kritz, Martyn P. Chipperfield, Deianeira Z. Stockwell, Joyce E. Penner, Claire E. Reeves, W. T. Blackshear, Department of Earth and Planetary Sciences [Cambridge, USA] (EPS), Harvard University [Cambridge], University of California [Irvine] (UCI), University of California, National Center for Atmospheric Research [Boulder] (NCAR), Atmospheric and Environmental Research, Inc. (AER), Laboratoire de Modélisation du Climat et de l'Environnement (LMCE), York University [Toronto], Lawrence Livermore National Laboratory (LLNL), NASA Langley Research Center [Hampton] (LaRC), Department of Applied Mathematics [Seattle], University of Washington [Seattle], Meteorological Research Institute [Tsukuba] (MRI), Japan Meteorological Agency (JMA), Department of Chemistry [Cambridge, UK], University of Cambridge [UK] (CAM), Max-Planck-Institut für Meteorologie (MPI-M), Max-Planck-Gesellschaft, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), School of Earth and Atmospheric Sciences [Atlanta], Georgia Institute of Technology [Atlanta], DLR Institut für Physik der Atmosphäre (IPA), Deutsches Zentrum für Luft- und Raumfahrt [Oberpfaffenhofen-Wessling] (DLR), Atmospheric Sciences Research Center (ASRC), University at Albany [SUNY], State University of New York (SUNY)-State University of New York (SUNY), Centre des Faibles Radioactivités, Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), School of Environmental and Life Sciences, University of East Anglia [Norwich] (UEA), Royal Netherlands Meteorological Institute (KNMI), Harvard University, University of California [Irvine] (UC Irvine), University of California (UC), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Convection, Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, Soil Science, Magnitude (mathematics), Zonal and meridional, 010501 environmental sciences, Aquatic Science, Oceanography, Atmospheric sciences, 01 natural sciences, Latitude, Troposphere, Geochemistry and Petrology, Atmospheric convection, Synoptic scale meteorology, Earth and Planetary Sciences (miscellaneous), 14. Life underwater, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Ecology, Paleontology, Forestry, Numerical diffusion, Geophysics, 13. Climate action, Space and Planetary Science, Environmental science
Abstract

International audience; Simulations of 222Rn and other short‐lived tracers are used to evaluate and intercompare the representations of convective and synoptic processes in 20 global atmospheric transport models. Results show that most established three‐dimensional models simulate vertical mixing in the troposphere to within the constraints offered by the observed mean 222Rn concentrations and that subgrid parameterization of convection is essential for this purpose. However, none of the models captures the observed variability of 222Rn concentrations in the upper troposphere, and none reproduces the high 222Rn concentrations measured at 200 hPa over Hawaii. The established three‐dimensional models reproduce the frequency and magnitude of high‐222Rn episodes observed at Crozet Island in the Indian Ocean, demonstrating that they can resolve the synoptic‐scale transport of continental plumes with no significant numerical diffusion. Large differences between models are found in the rates of meridional transport in the upper troposphere (interhemispheric exchange, exchange between tropics and high latitudes). The four two‐dimensional models which participated in the intercomparison tend to underestimate the rate of vertical transport from the lower to the upper troposphere but show concentrations of 222Rn in the lower troposphere that are comparable to the zonal mean values in the three‐dimensional models.

Published
1997
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20. Interannual signals in length of day and atmospheric angular momentum

Author

R. Abarco del Rio, D. Gambis, D. A. Salstein, Spaceflight Dynamics Department, International Earth Rotation Service, Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Atmospheric and Environmental Research, Inc. (AER), and EGU, Publication

Subjects
Angular momentum, Atmospheric Science, 010504 meteorology & atmospheric sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Atmospheric sciences, 010502 geochemistry & geophysics, 01 natural sciences, Latitude, Atmosphere, Troposphere, Earth and Planetary Sciences (miscellaneous), lcsh:Science, Stratosphere, 0105 earth and related environmental sciences, Physics, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Oscillation, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, lcsh:QC801-809, Geology, Astronomy and Astrophysics, lcsh:QC1-999, lcsh:Geophysics. Cosmic physics, Amplitude, 13. Climate action, Space and Planetary Science, [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, Polar, lcsh:Q, lcsh:Physics
Abstract

Atmospheric angular momentum (AAM) and length of day (LOD) series are investigated for their characteristics on interannual time scales during the half-century period 1949 to 1998. During this epoch, the interannual variability in LOD can be separated naturally into three bands: a quasi-biennial, a triennial-quadrennial and one at six-seven years. The atmosphere appears to excite the first two bands, while it does not contribute to the last. Considering the quasi-biennial (QB) band alone, the atmosphere appears to excite most of its signal in LOD, but it arises from separate fluctuations with stratospheric and tropospheric origin. Thus, although close in frequency, stratospheric and tropospheric processes differ in their amplitude and phase variability. The time shift can be noted especially during the strong El Niño events of 1982-83 and 1997-98 when both processes have positive phase and thus combine to help produce particularly strong peak in AAM and LOD. In addition, we have reconfirmed the downward propagation in the stratosphere and upward propagation in the troposphere of AAM observed in earlier studies for other variables. In the triennial-quadrennial (TQ) band, time-variable spectral analyses reveal that LOD and AAM contain strong variability, with periods shorter than four years before 1975 and longer thereafter. This signal originates mainly within the troposphere and propagates upwards from the lower to the higher layers of the troposphere. According to a zonal analysis, an equatorial poleward mode, strongly linked to the SOI, explains more than 60% of the total variability at these ranges. In addition, this study also indicates that an equatorward mode, originating within polar latitudes, explains, on average, more than 15% of the triennial-quadrennial oscillation (TQO) variability in AAM, and up to 30% at certain epochs. Finally, a six year period in LOD noted in earlier studies, as well as in lengthier series covering much of the century, is found to be absent in atmospheric excitations, and it is thus likely to arise from mantle/core interactions.Key words: Meteorology and atmospheric dynamics (general circulation) - Solar physics, astrophysics and astronomy (celestial mechanics)

Published
2000
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21. Sensitivity analysis of a model of CO2exchange in tundra ecosystems by the adjoint method

Author

C. Waelbroeck, J.-F. Louis, Laboratoire de Modélisation du Climat et de l'Environnement (LMCE), and Atmospheric and Environmental Research, Inc. (AER)

Subjects
0106 biological sciences, Atmospheric Science, 010504 meteorology & atmospheric sciences, Soil Science, Flux, Perturbation (astronomy), Aquatic Science, Oceanography, Atmospheric sciences, 010603 evolutionary biology, 01 natural sciences, Carbon cycle, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Sensitivity (control systems), [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Nitrogen cycle, Physics::Atmospheric and Oceanic Physics, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, Positive feedback, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Ecology, Paleontology, Primary production, Forestry, 15. Life on land, Tundra, Geophysics, 13. Climate action, Space and Planetary Science, Climatology, Environmental science
Abstract

International audience; A model of net primary production (NPP), decomposition, and nitrogen cycling in tundra ecosystems has been developed. The adjoint technique is used to study the sensitivity of the computed annual net CO2 flux to perturbations in initial conditions, climatic inputs, and model's main parameters describing current seasonal CO2 exchange in wet sedge tundra at Barrow, Alaska. The results show that net CO2 flux is most sensitive to parameters characterizing litter chemical composition and more sensitive to decomposition parameters than to NPP parameters. This underlines the fact that in nutrient-limited ecosystems, decomposition drives net CO2 exchange by controlling mineralization of main nutrients. The results also indicate that the shortterm (1 year) response of wet sedge tundra to CO2-induced warming is a significant increase in CO2 emission, creating a positive feedback to atmospheric CO2 accumulation. However, a cloudiness increase during the same year can severely alter this response and lead to either a slight decrease or a strong increase in emitted CO2, depending on its exact timing. These results demonstrate that the adjoint method is well suited to study systems encountering regime changes, as a single run of the adjoint model provides sensitivities of the net CO2 flux to perturbations in all parameters and variables at any time of the year. Moreover, it is shown that large errors due to the presence of thresholds can be avoided by first delimiting the range of applicability of the adjoint results.

Published
1995
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22. The Polar Amplification Model Intercomparison Project (PAMIP) contribution to CMIP6: investigating the causes and consequences of polar amplification

Author

Doug Smith, Xiangdong Zhang, Michael Sigmond, John C. Fyfe, Jin-Ho Yoon, Yannick Peings, Jinro Ukita, Vladimir M. Kattsov, Judah Cohen, Clara Deser, Javier García-Serrano, Rym Msadek, Thomas Jung, Daniela Matei, James A. Screen, Department of Chemistry [Bath], University of Bath [Bath], National Center for Atmospheric Research [Boulder] (NCAR), Atmospheric and Environmental Research, Inc. (AER), Institut Català de Ciènces del Clima (IC3), Max Planck Institute for Meteorology (MPI-M), Max-Planck-Gesellschaft, NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), Department of Earth System Science [Irvine] (ESS), University of California [Irvine] (UCI), University of California-University of California, Niigata University, Atmospheric Sciences and Global Change Division, and Pacific Northwest National Laboratory (PNNL)

Subjects
Coupled model intercomparison project, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, lcsh:QE1-996.5, Global warming, Polar Amplification, Climate change, Antarctic sea ice, 010502 geochemistry & geophysics, 01 natural sciences, Arctic ice pack, PAMIP, lcsh:Geology, 13. Climate action, Climatology, [SDE]Environmental Sciences, Sea ice, Polar amplification, Environmental science, Climate model, CMIP6, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

Polar amplification – the phenomenon where ex- ternal radiative forcing produces a larger change in surface temperature at high latitudes than the global average – is a key aspect of anthropogenic climate change, but its causes and consequences are not fully understood. The Polar Am- plification Model Intercomparison Project (PAMIP) contri- bution to the sixth Coupled Model Intercomparison Project (CMIP6; Eyring et al., 2016) seeks to improve our under- standing of this phenomenon through a coordinated set of numerical model experiments documented here. In partic- ular, PAMIP will address the following primary questions: (1) what are the relative roles of local sea ice and remote sea surface temperature changes in driving polar amplification? (2) How does the global climate system respond to changes in Arctic and Antarctic sea ice? These issues will be addressed with multi-model simulations that are forced with different combinations of sea ice and/or sea surface tempera- tures representing present-day, pre-industrial and future con- ditions. The use of three time periods allows the signals of interest to be diagnosed in multiple ways. Lower-priority tier experiments are proposed to investigate additional aspects and provide further understanding of the physical processes. These experiments will address the following specific ques- tions: what role does ocean–atmosphere coupling play in the response to sea ice? How and why does the atmospheric re- sponse to Arctic sea ice depend on the pattern of sea ice forcing? How and why does the atmospheric response to Arctic sea ice depend on the model background state? What have been the roles of local sea ice and remote sea surface temper- ature in polar amplification, and the response to sea ice, over the recent period since 1979? How does the response to sea ice evolve on decadal and longer timescales? A key goal of PAMIP is to determine the real-world sit- uation using imperfect climate models. Although the exper- iments proposed here form a coordinated set, we anticipate a large spread across models. However, this spread will be exploited by seeking “emergent constraints” in which model uncertainty may be reduced by using an observable quantity that physically explains the intermodel spread. In summary, PAMIP will improve our understanding of the physical pro- cesses that drive polar amplification and its global climate impacts, thereby reducing the uncertainties in future projec- tions and predictions of climate change and variability.

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