Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry
Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Ant...
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crcambridgeupr:10.1017/jog.2021.8 2024-04-07T07:47:42+00:00 Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry Zwally, H. Jay Robbins, John W. Luthcke, Scott B. Loomis, Bryant D. Rémy, Frédérique 2021 http://dx.doi.org/10.1017/jog.2021.8 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000083 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 67, issue 263, page 533-559 ISSN 0022-1430 1727-5652 Earth-Surface Processes journal-article 2021 crcambridgeupr https://doi.org/10.1017/jog.2021.8 2024-03-08T00:33:18Z Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm −3 . Derived sensitivities ( S g , S a ) to bedrock motion enable calculation of motion ( δ B 0 ) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δ B 0 is −2.2 mm a −1 subsidence with mass matching at 150 Gt a −1 , inland WA is −3.5 mm a −1 at 66 Gt a −1 , and coastal WA is only −0.35 mm a −1 at −95 Gt a −1 . WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a −1 , the Antarctic total gain is 95 ± 25 Gt a −1 during 2003–08, compared to 144 ± 61 Gt a −1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a −1 by 2012–16. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica East Antarctica Ice Sheet Journal of Glaciology West Antarctica Cambridge University Press Antarctic The Antarctic Antarctic Peninsula East Antarctica West Antarctica Journal of Glaciology 67 263 533 559 |
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Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
topic |
Earth-Surface Processes |
spellingShingle |
Earth-Surface Processes Zwally, H. Jay Robbins, John W. Luthcke, Scott B. Loomis, Bryant D. Rémy, Frédérique Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
topic_facet |
Earth-Surface Processes |
description |
Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm −3 . Derived sensitivities ( S g , S a ) to bedrock motion enable calculation of motion ( δ B 0 ) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δ B 0 is −2.2 mm a −1 subsidence with mass matching at 150 Gt a −1 , inland WA is −3.5 mm a −1 at 66 Gt a −1 , and coastal WA is only −0.35 mm a −1 at −95 Gt a −1 . WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a −1 , the Antarctic total gain is 95 ± 25 Gt a −1 during 2003–08, compared to 144 ± 61 Gt a −1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a −1 by 2012–16. |
format |
Article in Journal/Newspaper |
author |
Zwally, H. Jay Robbins, John W. Luthcke, Scott B. Loomis, Bryant D. Rémy, Frédérique |
author_facet |
Zwally, H. Jay Robbins, John W. Luthcke, Scott B. Loomis, Bryant D. Rémy, Frédérique |
author_sort |
Zwally, H. Jay |
title |
Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
title_short |
Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
title_full |
Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
title_fullStr |
Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
title_full_unstemmed |
Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |
title_sort |
mass balance of the antarctic ice sheet 1992–2016: reconciling results from grace gravimetry with icesat, ers1/2 and envisat altimetry |
publisher |
Cambridge University Press (CUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1017/jog.2021.8 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000083 |
geographic |
Antarctic The Antarctic Antarctic Peninsula East Antarctica West Antarctica |
geographic_facet |
Antarctic The Antarctic Antarctic Peninsula East Antarctica West Antarctica |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica East Antarctica Ice Sheet Journal of Glaciology West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica East Antarctica Ice Sheet Journal of Glaciology West Antarctica |
op_source |
Journal of Glaciology volume 67, issue 263, page 533-559 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2021.8 |
container_title |
Journal of Glaciology |
container_volume |
67 |
container_issue |
263 |
container_start_page |
533 |
op_container_end_page |
559 |
_version_ |
1795674825498296320 |