Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet
A new methodology for retrieval of glacier and ice sheet elevations and elevation changes from CryoSat-2 data is presented. Surface elevations and elevation changes determined using this approach show significant improvements over ESA's publicly available CryoSat-2 elevation product (L2 Baselin...
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ftdoajarticles:oai:doaj.org/article:c7d5bde431cf4b4a8008c94c03c55bb0 2023-05-15T16:21:24+02:00 Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet J. Nilsson A. Gardner L. Sandberg Sørensen R. Forsberg 2016-12-01T00:00:00Z https://doi.org/10.5194/tc-10-2953-2016 https://doaj.org/article/c7d5bde431cf4b4a8008c94c03c55bb0 EN eng Copernicus Publications http://www.the-cryosphere.net/10/2953/2016/tc-10-2953-2016.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-10-2953-2016 https://doaj.org/article/c7d5bde431cf4b4a8008c94c03c55bb0 The Cryosphere, Vol 10, Iss 6, Pp 2953-2969 (2016) Environmental sciences GE1-350 Geology QE1-996.5 article 2016 ftdoajarticles https://doi.org/10.5194/tc-10-2953-2016 2022-12-31T01:13:00Z A new methodology for retrieval of glacier and ice sheet elevations and elevation changes from CryoSat-2 data is presented. Surface elevations and elevation changes determined using this approach show significant improvements over ESA's publicly available CryoSat-2 elevation product (L2 Baseline-B). The results are compared to near-coincident airborne laser altimetry from NASA's Operation IceBridge and seasonal height amplitudes from the Ice, Cloud, and Elevation Satellite (ICESat). Applying this methodology to CryoSat-2 data collected in interferometric synthetic aperture mode (SIN) over the high-relief regions of the Greenland Ice Sheet we find an improvement in the root-mean-square error (RMSE) of 27 and 40 % compared to ESA's L2 product in the derived elevation and elevation changes, respectively. In the interior part of the ice sheet, where CryoSat-2 operates in low-resolution mode (LRM), we find an improvement in the RMSE of 68 and 55 % in the derived elevation and elevation changes, respectively. There is also an 86 % improvement in the magnitude of the seasonal amplitudes when compared to amplitudes derived from ICESat data. These results indicate that the new methodology provides improved tracking of the snow/ice surface with lower sensitivity to changes in near-surface dielectric properties. To demonstrate the utility of the new processing methodology we produce elevations, elevation changes, and total volume changes from CryoSat-2 data for the Greenland Ice Sheet during the period January 2011 to January 2015. We find that the Greenland Ice Sheet decreased in volume at a rate of 289 ± 20 km 3 <mspace linebreak="nobreak" width="0.125em"/>a −1 , with high interannual variability and spatial heterogeneity in rates of loss. This rate is 65 km 3 <mspace linebreak="nobreak" width="0.125em"/>a −1 more negative than rates determined from ESA's L2 product, highlighting the importance of CryoSat-2 processing methodologies. Article in Journal/Newspaper glacier Greenland Ice Sheet The Cryosphere Directory of Open Access Journals: DOAJ Articles Greenland The Cryosphere 10 6 2953 2969 |
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 J. Nilsson A. Gardner L. Sandberg Sørensen R. Forsberg Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
A new methodology for retrieval of glacier and ice sheet elevations and elevation changes from CryoSat-2 data is presented. Surface elevations and elevation changes determined using this approach show significant improvements over ESA's publicly available CryoSat-2 elevation product (L2 Baseline-B). The results are compared to near-coincident airborne laser altimetry from NASA's Operation IceBridge and seasonal height amplitudes from the Ice, Cloud, and Elevation Satellite (ICESat). Applying this methodology to CryoSat-2 data collected in interferometric synthetic aperture mode (SIN) over the high-relief regions of the Greenland Ice Sheet we find an improvement in the root-mean-square error (RMSE) of 27 and 40 % compared to ESA's L2 product in the derived elevation and elevation changes, respectively. In the interior part of the ice sheet, where CryoSat-2 operates in low-resolution mode (LRM), we find an improvement in the RMSE of 68 and 55 % in the derived elevation and elevation changes, respectively. There is also an 86 % improvement in the magnitude of the seasonal amplitudes when compared to amplitudes derived from ICESat data. These results indicate that the new methodology provides improved tracking of the snow/ice surface with lower sensitivity to changes in near-surface dielectric properties. To demonstrate the utility of the new processing methodology we produce elevations, elevation changes, and total volume changes from CryoSat-2 data for the Greenland Ice Sheet during the period January 2011 to January 2015. We find that the Greenland Ice Sheet decreased in volume at a rate of 289 ± 20 km 3 <mspace linebreak="nobreak" width="0.125em"/>a −1 , with high interannual variability and spatial heterogeneity in rates of loss. This rate is 65 km 3 <mspace linebreak="nobreak" width="0.125em"/>a −1 more negative than rates determined from ESA's L2 product, highlighting the importance of CryoSat-2 processing methodologies. |
format |
Article in Journal/Newspaper |
author |
J. Nilsson A. Gardner L. Sandberg Sørensen R. Forsberg |
author_facet |
J. Nilsson A. Gardner L. Sandberg Sørensen R. Forsberg |
author_sort |
J. Nilsson |
title |
Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
title_short |
Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
title_full |
Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
title_fullStr |
Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
title_full_unstemmed |
Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet |
title_sort |
improved retrieval of land ice topography from cryosat-2 data and its impact for volume-change estimation of the greenland ice sheet |
publisher |
Copernicus Publications |
publishDate |
2016 |
url |
https://doi.org/10.5194/tc-10-2953-2016 https://doaj.org/article/c7d5bde431cf4b4a8008c94c03c55bb0 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
glacier Greenland Ice Sheet The Cryosphere |
genre_facet |
glacier Greenland Ice Sheet The Cryosphere |
op_source |
The Cryosphere, Vol 10, Iss 6, Pp 2953-2969 (2016) |
op_relation |
http://www.the-cryosphere.net/10/2953/2016/tc-10-2953-2016.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-10-2953-2016 https://doaj.org/article/c7d5bde431cf4b4a8008c94c03c55bb0 |
op_doi |
https://doi.org/10.5194/tc-10-2953-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
6 |
container_start_page |
2953 |
op_container_end_page |
2969 |
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1766009400497012736 |