Modeling time series of microwave brightness temperature in Antarctica
International audience This paper aims to interpret the temporal variations of microwave brightness temperature (at 19 and 37 GHz and at vertical and horizontal polarizations) in Antarctica using a physically based snow dynamic and emission model (SDEM). SDEM predicts time series of top-of-atmospher...
Published in: | Journal of Glaciology |
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Main Authors: | , , , , |
Other Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2009
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Online Access: | https://insu.hal.science/insu-00421243 https://insu.hal.science/insu-00421243/document https://insu.hal.science/insu-00421243/file/modeling-time-series-of-microwave-brightness-temperature-in-antarctica.pdf https://doi.org/10.3189/002214309788816678 |
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ftunigrenoble:oai:HAL:insu-00421243v1 |
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openpolar |
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Open Polar |
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Université Grenoble Alpes: HAL |
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ftunigrenoble |
language |
English |
topic |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
spellingShingle |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology Picard, Ghislain Brucker, Ludovic Fily, Michel Gallée, Hubert Krinner, Gerhard Modeling time series of microwave brightness temperature in Antarctica |
topic_facet |
[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
description |
International audience This paper aims to interpret the temporal variations of microwave brightness temperature (at 19 and 37 GHz and at vertical and horizontal polarizations) in Antarctica using a physically based snow dynamic and emission model (SDEM). SDEM predicts time series of top-of-atmosphere brightness temperature from widely available surface meteorological data (ERA-40 re-analysis). To do so, it successively computes the heat flux incoming the snowpack, the snow temperature profile, the microwaves emitted by the snow and, finally, the propagation of the microwaves through the atmosphere up to the satellite. Since the model contains several parameters whose value is variable and uncertain across the continent, the parameter values are optimized for every 50 km × 50 km pixel. Simulation results show that the model is inadequate in the melt zone (where surface melting occurs on at least a few days a year) because the snowpack structure and its temporal variations are too complex. In contrast, the accuracy is reasonably good in the dry zone and varies between 2 and 4 K depending on the frequency and polarization of observations and on the location. At the Antarctic scale, the error is larger where wind is usually stronger, suggesting either that meteorological data are less accurate in windy regions or that some neglected processes (e.g. windpumping, surface scouring) are important. At Dome C, in calm conditions, a detailed analysis shows that most of the error is due to inaccuracy of the ERA-40 air temperature (∼2 K). Finally, the paper discusses the values of the optimized parameters and their spatial variations across the Antarctic. |
author2 |
Laboratoire de glaciologie et géophysique de l'environnement (LGGE) 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) the French Remote Sensing program (Programme National de Télédétection Spatiale) and the NIEVE project in the LEFE (Les Enveloppes Fluids et l'Environnement)/EVE (Evolution et Variabilité du climat à l'Echelle globale) program. |
format |
Article in Journal/Newspaper |
author |
Picard, Ghislain Brucker, Ludovic Fily, Michel Gallée, Hubert Krinner, Gerhard |
author_facet |
Picard, Ghislain Brucker, Ludovic Fily, Michel Gallée, Hubert Krinner, Gerhard |
author_sort |
Picard, Ghislain |
title |
Modeling time series of microwave brightness temperature in Antarctica |
title_short |
Modeling time series of microwave brightness temperature in Antarctica |
title_full |
Modeling time series of microwave brightness temperature in Antarctica |
title_fullStr |
Modeling time series of microwave brightness temperature in Antarctica |
title_full_unstemmed |
Modeling time series of microwave brightness temperature in Antarctica |
title_sort |
modeling time series of microwave brightness temperature in antarctica |
publisher |
HAL CCSD |
publishDate |
2009 |
url |
https://insu.hal.science/insu-00421243 https://insu.hal.science/insu-00421243/document https://insu.hal.science/insu-00421243/file/modeling-time-series-of-microwave-brightness-temperature-in-antarctica.pdf https://doi.org/10.3189/002214309788816678 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Antarctica Journal of Glaciology |
genre_facet |
Antarc* Antarctic Antarctica Journal of Glaciology |
op_source |
ISSN: 0022-1430 EISSN: 1727-5652 Journal of Glaciology https://insu.hal.science/insu-00421243 Journal of Glaciology, 2009, 55 (191), pp.537-551. ⟨10.3189/002214309788816678⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3189/002214309788816678 insu-00421243 https://insu.hal.science/insu-00421243 https://insu.hal.science/insu-00421243/document https://insu.hal.science/insu-00421243/file/modeling-time-series-of-microwave-brightness-temperature-in-antarctica.pdf doi:10.3189/002214309788816678 |
op_rights |
http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3189/002214309788816678 |
container_title |
Journal of Glaciology |
container_volume |
55 |
container_issue |
191 |
container_start_page |
537 |
op_container_end_page |
551 |
_version_ |
1798834988002574336 |
spelling |
ftunigrenoble:oai:HAL:insu-00421243v1 2024-05-12T07:55:14+00:00 Modeling time series of microwave brightness temperature in Antarctica Picard, Ghislain Brucker, Ludovic Fily, Michel Gallée, Hubert Krinner, Gerhard Laboratoire de glaciologie et géophysique de l'environnement (LGGE) 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) the French Remote Sensing program (Programme National de Télédétection Spatiale) and the NIEVE project in the LEFE (Les Enveloppes Fluids et l'Environnement)/EVE (Evolution et Variabilité du climat à l'Echelle globale) program. 2009-06 https://insu.hal.science/insu-00421243 https://insu.hal.science/insu-00421243/document https://insu.hal.science/insu-00421243/file/modeling-time-series-of-microwave-brightness-temperature-in-antarctica.pdf https://doi.org/10.3189/002214309788816678 en eng HAL CCSD International Glaciological Society info:eu-repo/semantics/altIdentifier/doi/10.3189/002214309788816678 insu-00421243 https://insu.hal.science/insu-00421243 https://insu.hal.science/insu-00421243/document https://insu.hal.science/insu-00421243/file/modeling-time-series-of-microwave-brightness-temperature-in-antarctica.pdf doi:10.3189/002214309788816678 http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess ISSN: 0022-1430 EISSN: 1727-5652 Journal of Glaciology https://insu.hal.science/insu-00421243 Journal of Glaciology, 2009, 55 (191), pp.537-551. ⟨10.3189/002214309788816678⟩ [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology info:eu-repo/semantics/article Journal articles 2009 ftunigrenoble https://doi.org/10.3189/002214309788816678 2024-04-18T03:12:00Z International audience This paper aims to interpret the temporal variations of microwave brightness temperature (at 19 and 37 GHz and at vertical and horizontal polarizations) in Antarctica using a physically based snow dynamic and emission model (SDEM). SDEM predicts time series of top-of-atmosphere brightness temperature from widely available surface meteorological data (ERA-40 re-analysis). To do so, it successively computes the heat flux incoming the snowpack, the snow temperature profile, the microwaves emitted by the snow and, finally, the propagation of the microwaves through the atmosphere up to the satellite. Since the model contains several parameters whose value is variable and uncertain across the continent, the parameter values are optimized for every 50 km × 50 km pixel. Simulation results show that the model is inadequate in the melt zone (where surface melting occurs on at least a few days a year) because the snowpack structure and its temporal variations are too complex. In contrast, the accuracy is reasonably good in the dry zone and varies between 2 and 4 K depending on the frequency and polarization of observations and on the location. At the Antarctic scale, the error is larger where wind is usually stronger, suggesting either that meteorological data are less accurate in windy regions or that some neglected processes (e.g. windpumping, surface scouring) are important. At Dome C, in calm conditions, a detailed analysis shows that most of the error is due to inaccuracy of the ERA-40 air temperature (∼2 K). Finally, the paper discusses the values of the optimized parameters and their spatial variations across the Antarctic. Article in Journal/Newspaper Antarc* Antarctic Antarctica Journal of Glaciology Université Grenoble Alpes: HAL Antarctic The Antarctic Journal of Glaciology 55 191 537 551 |