Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet
Spaceborne radar altimeters are a valuable tool for observing the Antarctic Ice Sheet. The radar wave interaction with the snow provides information on both the surface and the subsurface of the snowpack due to its dependence on the snow properties. However, the penetration of the radar wave within...
Published in: | The Cryosphere |
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Copernicus Publications
2018
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00005930 2023-05-15T13:34:49+02:00 Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet Adodo, Fifi Ibrahime Remy, Frédérique Picard, Ghislain 2018-05 electronic https://doi.org/10.5194/tc-12-1767-2018 https://noa.gwlb.de/receive/cop_mods_00005930 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00005887/tc-12-1767-2018.pdf https://tc.copernicus.org/articles/12/1767/2018/tc-12-1767-2018.pdf eng eng Copernicus Publications The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-12-1767-2018 https://noa.gwlb.de/receive/cop_mods_00005930 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00005887/tc-12-1767-2018.pdf https://tc.copernicus.org/articles/12/1767/2018/tc-12-1767-2018.pdf https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess CC-BY article Verlagsveröffentlichung article Text doc-type:article 2018 ftnonlinearchiv https://doi.org/10.5194/tc-12-1767-2018 2022-02-08T22:59:14Z Spaceborne radar altimeters are a valuable tool for observing the Antarctic Ice Sheet. The radar wave interaction with the snow provides information on both the surface and the subsurface of the snowpack due to its dependence on the snow properties. However, the penetration of the radar wave within the snowpack also induces a negative bias on the estimated surface elevation. Empirical corrections of this space- and time-varying bias are usually based on the backscattering coefficient variability. We investigate the spatial and seasonal variations of the backscattering coefficient at the S (3.2 GHz ∼ 9.4 cm), Ku (13.6 GHz ∼ 2.3 cm) and Ka (37 GHz ∼ 0.8 cm) bands. We identified that the backscattering coefficient at Ku band reaches a maximum in winter in part of the continent (Region 1) and in the summer in the remaining (Region 2), while the evolution at other frequencies is relatively uniform over the whole continent. To explain this contrasting behavior between frequencies and between regions, we studied the sensitivity of the backscattering coefficient at three frequencies to several parameters (surface snow density, snow temperature and snow grain size) using an electromagnetic model. The results show that the seasonal cycle of the backscattering coefficient at Ka frequency is dominated by the volume echo and is mainly driven by snow temperature evolution everywhere. In contrast, at S band, the cycle is dominated by the surface echo. At Ku band, the seasonal cycle is dominated by the volume echo in Region 1 and by the surface echo in Region 2. This investigation provides new information on the seasonal dynamics of the Antarctic Ice Sheet surface and provides new clues to build more accurate corrections of the radar altimeter surface elevation signal in the future. Article in Journal/Newspaper Antarc* Antarctic Ice Sheet The Cryosphere Niedersächsisches Online-Archiv NOA Antarctic The Antarctic The Cryosphere 12 5 1767 1778 |
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Niedersächsisches Online-Archiv NOA |
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ftnonlinearchiv |
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English |
topic |
article Verlagsveröffentlichung |
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article Verlagsveröffentlichung Adodo, Fifi Ibrahime Remy, Frédérique Picard, Ghislain Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
topic_facet |
article Verlagsveröffentlichung |
description |
Spaceborne radar altimeters are a valuable tool for observing the Antarctic Ice Sheet. The radar wave interaction with the snow provides information on both the surface and the subsurface of the snowpack due to its dependence on the snow properties. However, the penetration of the radar wave within the snowpack also induces a negative bias on the estimated surface elevation. Empirical corrections of this space- and time-varying bias are usually based on the backscattering coefficient variability. We investigate the spatial and seasonal variations of the backscattering coefficient at the S (3.2 GHz ∼ 9.4 cm), Ku (13.6 GHz ∼ 2.3 cm) and Ka (37 GHz ∼ 0.8 cm) bands. We identified that the backscattering coefficient at Ku band reaches a maximum in winter in part of the continent (Region 1) and in the summer in the remaining (Region 2), while the evolution at other frequencies is relatively uniform over the whole continent. To explain this contrasting behavior between frequencies and between regions, we studied the sensitivity of the backscattering coefficient at three frequencies to several parameters (surface snow density, snow temperature and snow grain size) using an electromagnetic model. The results show that the seasonal cycle of the backscattering coefficient at Ka frequency is dominated by the volume echo and is mainly driven by snow temperature evolution everywhere. In contrast, at S band, the cycle is dominated by the surface echo. At Ku band, the seasonal cycle is dominated by the volume echo in Region 1 and by the surface echo in Region 2. This investigation provides new information on the seasonal dynamics of the Antarctic Ice Sheet surface and provides new clues to build more accurate corrections of the radar altimeter surface elevation signal in the future. |
format |
Article in Journal/Newspaper |
author |
Adodo, Fifi Ibrahime Remy, Frédérique Picard, Ghislain |
author_facet |
Adodo, Fifi Ibrahime Remy, Frédérique Picard, Ghislain |
author_sort |
Adodo, Fifi Ibrahime |
title |
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
title_short |
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
title_full |
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
title_fullStr |
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
title_full_unstemmed |
Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet |
title_sort |
seasonal variations of the backscattering coefficient measured by radar altimeters over the antarctic ice sheet |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-1767-2018 https://noa.gwlb.de/receive/cop_mods_00005930 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00005887/tc-12-1767-2018.pdf https://tc.copernicus.org/articles/12/1767/2018/tc-12-1767-2018.pdf |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Ice Sheet The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet The Cryosphere |
op_relation |
The Cryosphere -- ˜Theœ Cryosphere -- http://www.bibliothek.uni-regensburg.de/ezeit/?2393169 -- http://www.the-cryosphere.net/ -- 1994-0424 https://doi.org/10.5194/tc-12-1767-2018 https://noa.gwlb.de/receive/cop_mods_00005930 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00005887/tc-12-1767-2018.pdf https://tc.copernicus.org/articles/12/1767/2018/tc-12-1767-2018.pdf |
op_rights |
https://creativecommons.org/licenses/by/4.0/ uneingeschränkt info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-12-1767-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
5 |
container_start_page |
1767 |
op_container_end_page |
1778 |
_version_ |
1766058185158819840 |