Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice
Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistribution over Arctic sea ice on radar waveforms and backscatter signatures obtained from a su...
Published in: | The Cryosphere |
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2023
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Online Access: | https://doi.org/10.5194/tc-17-2211-2023 https://doaj.org/article/0d534129bf89421db91797da9a4e31b1 |
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ftdoajarticles:oai:doaj.org/article:0d534129bf89421db91797da9a4e31b1 2023-06-18T03:39:10+02:00 Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice V. Nandan R. Willatt R. Mallett J. Stroeve T. Geldsetzer R. Scharien R. Tonboe J. Yackel J. Landy D. Clemens-Sewall A. Jutila D. N. Wagner D. Krampe M. Huntemann M. Mahmud D. Jensen T. Newman S. Hendricks G. Spreen A. Macfarlane M. Schneebeli J. Mead R. Ricker M. Gallagher C. Duguay I. Raphael C. Polashenski M. Tsamados I. Matero M. Hoppmann 2023-06-01T00:00:00Z https://doi.org/10.5194/tc-17-2211-2023 https://doaj.org/article/0d534129bf89421db91797da9a4e31b1 EN eng Copernicus Publications https://tc.copernicus.org/articles/17/2211/2023/tc-17-2211-2023.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-17-2211-2023 1994-0416 1994-0424 https://doaj.org/article/0d534129bf89421db91797da9a4e31b1 The Cryosphere, Vol 17, Pp 2211-2229 (2023) Environmental sciences GE1-350 Geology QE1-996.5 article 2023 ftdoajarticles https://doi.org/10.5194/tc-17-2211-2023 2023-06-04T00:33:41Z Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistribution over Arctic sea ice on radar waveforms and backscatter signatures obtained from a surface-based, fully polarimetric Ka- and Ku-band radar at incidence angles between 0 ∘ (nadir) and 50 ∘ . Two wind events in November 2019 during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition are evaluated. During both events, changes in Ka- and Ku-band radar waveforms and backscatter coefficients at nadir are observed, coincident with surface topography changes measured by a terrestrial laser scanner. At both frequencies, redistribution caused snow densification at the surface and the uppermost layers, increasing the scattering at the air–snow interface at nadir and its prevalence as the dominant radar scattering surface. The waveform data also detected the presence of previous air–snow interfaces, buried beneath newly deposited snow. The additional scattering from previous air–snow interfaces could therefore affect the range retrieved from Ka- and Ku-band satellite altimeters. With increasing incidence angles, the relative scattering contribution of the air–snow interface decreases, and the snow–sea ice interface scattering increases. Relative to pre-wind event conditions, azimuthally averaged backscatter at nadir during the wind events increases by up to 8 dB (Ka-band) and 5 dB (Ku-band). Results show substantial backscatter variability within the scan area at all incidence angles and polarizations, in response to increasing wind speed and changes in wind direction. Our results show that snow redistribution and wind compaction need to be accounted for to interpret airborne and satellite radar measurements of snow-covered sea ice. Article in Journal/Newspaper Arctic Sea ice The Cryosphere Directory of Open Access Journals: DOAJ Articles Arctic The Cryosphere 17 6 2211 2229 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 V. Nandan R. Willatt R. Mallett J. Stroeve T. Geldsetzer R. Scharien R. Tonboe J. Yackel J. Landy D. Clemens-Sewall A. Jutila D. N. Wagner D. Krampe M. Huntemann M. Mahmud D. Jensen T. Newman S. Hendricks G. Spreen A. Macfarlane M. Schneebeli J. Mead R. Ricker M. Gallagher C. Duguay I. Raphael C. Polashenski M. Tsamados I. Matero M. Hoppmann Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Wind-driven redistribution of snow on sea ice alters its topography and microstructure, yet the impact of these processes on radar signatures is poorly understood. Here, we examine the effects of snow redistribution over Arctic sea ice on radar waveforms and backscatter signatures obtained from a surface-based, fully polarimetric Ka- and Ku-band radar at incidence angles between 0 ∘ (nadir) and 50 ∘ . Two wind events in November 2019 during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition are evaluated. During both events, changes in Ka- and Ku-band radar waveforms and backscatter coefficients at nadir are observed, coincident with surface topography changes measured by a terrestrial laser scanner. At both frequencies, redistribution caused snow densification at the surface and the uppermost layers, increasing the scattering at the air–snow interface at nadir and its prevalence as the dominant radar scattering surface. The waveform data also detected the presence of previous air–snow interfaces, buried beneath newly deposited snow. The additional scattering from previous air–snow interfaces could therefore affect the range retrieved from Ka- and Ku-band satellite altimeters. With increasing incidence angles, the relative scattering contribution of the air–snow interface decreases, and the snow–sea ice interface scattering increases. Relative to pre-wind event conditions, azimuthally averaged backscatter at nadir during the wind events increases by up to 8 dB (Ka-band) and 5 dB (Ku-band). Results show substantial backscatter variability within the scan area at all incidence angles and polarizations, in response to increasing wind speed and changes in wind direction. Our results show that snow redistribution and wind compaction need to be accounted for to interpret airborne and satellite radar measurements of snow-covered sea ice. |
format |
Article in Journal/Newspaper |
author |
V. Nandan R. Willatt R. Mallett J. Stroeve T. Geldsetzer R. Scharien R. Tonboe J. Yackel J. Landy D. Clemens-Sewall A. Jutila D. N. Wagner D. Krampe M. Huntemann M. Mahmud D. Jensen T. Newman S. Hendricks G. Spreen A. Macfarlane M. Schneebeli J. Mead R. Ricker M. Gallagher C. Duguay I. Raphael C. Polashenski M. Tsamados I. Matero M. Hoppmann |
author_facet |
V. Nandan R. Willatt R. Mallett J. Stroeve T. Geldsetzer R. Scharien R. Tonboe J. Yackel J. Landy D. Clemens-Sewall A. Jutila D. N. Wagner D. Krampe M. Huntemann M. Mahmud D. Jensen T. Newman S. Hendricks G. Spreen A. Macfarlane M. Schneebeli J. Mead R. Ricker M. Gallagher C. Duguay I. Raphael C. Polashenski M. Tsamados I. Matero M. Hoppmann |
author_sort |
V. Nandan |
title |
Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
title_short |
Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
title_full |
Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
title_fullStr |
Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
title_full_unstemmed |
Wind redistribution of snow impacts the Ka- and Ku-band radar signatures of Arctic sea ice |
title_sort |
wind redistribution of snow impacts the ka- and ku-band radar signatures of arctic sea ice |
publisher |
Copernicus Publications |
publishDate |
2023 |
url |
https://doi.org/10.5194/tc-17-2211-2023 https://doaj.org/article/0d534129bf89421db91797da9a4e31b1 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Sea ice The Cryosphere |
genre_facet |
Arctic Sea ice The Cryosphere |
op_source |
The Cryosphere, Vol 17, Pp 2211-2229 (2023) |
op_relation |
https://tc.copernicus.org/articles/17/2211/2023/tc-17-2211-2023.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-17-2211-2023 1994-0416 1994-0424 https://doaj.org/article/0d534129bf89421db91797da9a4e31b1 |
op_doi |
https://doi.org/10.5194/tc-17-2211-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
6 |
container_start_page |
2211 |
op_container_end_page |
2229 |
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1769003972724523008 |