Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes
peer reviewed The Antarctic ice sheet mass balance is a major component of the sea level budget and results from the difference of two fluxes of a similar magnitude: ice flow discharging in the ocean and net snow accumulation on the ice sheet surface, i.e. the surface mass balance (SMB). Separately...
Published in: | The Cryosphere |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Copernicus Group
2019
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Online Access: | https://orbi.uliege.be/handle/2268/232308 https://orbi.uliege.be/bitstream/2268/232308/1/tc-13-281-2019.pdf https://doi.org/10.5194/tc-13-281-2019 |
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ftorbi:oai:orbi.ulg.ac.be:2268/232308 2024-04-21T07:49:49+00:00 Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes Agosta, Cécile Amory, Charles Kittel, Christoph Orsi, Anais Favier, Vincent Gallée, Hubert van den Broeke, Michiel R. Lenearts, Jan T. M. van Wessem, Jan Melchior van de Berg, Willem Jan Fettweis, Xavier 2019-01-29 https://orbi.uliege.be/handle/2268/232308 https://orbi.uliege.be/bitstream/2268/232308/1/tc-13-281-2019.pdf https://doi.org/10.5194/tc-13-281-2019 en eng Copernicus Group urn:issn:1994-0416 urn:issn:1994-0424 https://orbi.uliege.be/handle/2268/232308 info:hdl:2268/232308 https://orbi.uliege.be/bitstream/2268/232308/1/tc-13-281-2019.pdf doi:10.5194/tc-13-281-2019 scopus-id:2-s2.0-85060861641 open access http://purl.org/coar/access_right/c_abf2 info:eu-repo/semantics/openAccess The Cryosphere (2019-01-29) Antarctic Surface Mass Balance MAR Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique journal article http://purl.org/coar/resource_type/c_6501 info:eu-repo/semantics/article peer reviewed 2019 ftorbi https://doi.org/10.5194/tc-13-281-2019 2024-03-27T14:58:15Z peer reviewed The Antarctic ice sheet mass balance is a major component of the sea level budget and results from the difference of two fluxes of a similar magnitude: ice flow discharging in the ocean and net snow accumulation on the ice sheet surface, i.e. the surface mass balance (SMB). Separately modelling ice dynamics and SMB is the only way to project future trends. In addition, mass balance studies frequently use regional climate models (RCMs) outputs as an alternative to observed fields because SMB observations are particularly scarce on the ice sheet. Here we evaluate new simulations of the polar RCM MAR forced by three reanalyses, ERA-Interim, JRA-55, and MERRA-2, for the period 1979–2015, and we compare MAR results to the last outputs of the RCM RACMO2 forced by ERA-Interim. We show that MAR and RACMO2 perform similarly well in simulating coast-to-plateau SMB gradients, and we find no significant differences in their simulated SMB when integrated over the ice sheet or its major basins. More importantly, we outline and quantify missing or underestimated processes in both RCMs. Along stake transects, we show that both models accumulate too much snow on crests, and not enough snow in valleys, as a result of drifting snow transport fluxes not included in MAR and probably underestimated in RACMO2 by a factor of 3. Our results tend to confirm that drifting snow transport and sublimation fluxes are much larger than previous model-based estimates and need to be better resolved and constrained in climate models. Sublimation of precipitating particles in low-level atmospheric layers is responsible for the significantly lower snowfall rates in MAR than in RACMO2 in katabatic channels at the ice sheet margins. Atmospheric sublimation in MAR represents 363 Gt yr−1 over the grounded ice sheet for the year 2015, which is 16 % of the simulated snowfall loaded at the ground. This estimate is consistent with a recent study based on precipitation radar observations and is more than twice as much as simulated in RACMO2 ... Article in Journal/Newspaper Antarc* Antarctic Ice Sheet The Cryosphere University of Liège: ORBi (Open Repository and Bibliography) The Cryosphere 13 1 281 296 |
institution |
Open Polar |
collection |
University of Liège: ORBi (Open Repository and Bibliography) |
op_collection_id |
ftorbi |
language |
English |
topic |
Antarctic Surface Mass Balance MAR Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique |
spellingShingle |
Antarctic Surface Mass Balance MAR Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique Agosta, Cécile Amory, Charles Kittel, Christoph Orsi, Anais Favier, Vincent Gallée, Hubert van den Broeke, Michiel R. Lenearts, Jan T. M. van Wessem, Jan Melchior van de Berg, Willem Jan Fettweis, Xavier Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
topic_facet |
Antarctic Surface Mass Balance MAR Physical chemical mathematical & earth Sciences Earth sciences & physical geography Physique chimie mathématiques & sciences de la terre Sciences de la terre & géographie physique |
description |
peer reviewed The Antarctic ice sheet mass balance is a major component of the sea level budget and results from the difference of two fluxes of a similar magnitude: ice flow discharging in the ocean and net snow accumulation on the ice sheet surface, i.e. the surface mass balance (SMB). Separately modelling ice dynamics and SMB is the only way to project future trends. In addition, mass balance studies frequently use regional climate models (RCMs) outputs as an alternative to observed fields because SMB observations are particularly scarce on the ice sheet. Here we evaluate new simulations of the polar RCM MAR forced by three reanalyses, ERA-Interim, JRA-55, and MERRA-2, for the period 1979–2015, and we compare MAR results to the last outputs of the RCM RACMO2 forced by ERA-Interim. We show that MAR and RACMO2 perform similarly well in simulating coast-to-plateau SMB gradients, and we find no significant differences in their simulated SMB when integrated over the ice sheet or its major basins. More importantly, we outline and quantify missing or underestimated processes in both RCMs. Along stake transects, we show that both models accumulate too much snow on crests, and not enough snow in valleys, as a result of drifting snow transport fluxes not included in MAR and probably underestimated in RACMO2 by a factor of 3. Our results tend to confirm that drifting snow transport and sublimation fluxes are much larger than previous model-based estimates and need to be better resolved and constrained in climate models. Sublimation of precipitating particles in low-level atmospheric layers is responsible for the significantly lower snowfall rates in MAR than in RACMO2 in katabatic channels at the ice sheet margins. Atmospheric sublimation in MAR represents 363 Gt yr−1 over the grounded ice sheet for the year 2015, which is 16 % of the simulated snowfall loaded at the ground. This estimate is consistent with a recent study based on precipitation radar observations and is more than twice as much as simulated in RACMO2 ... |
format |
Article in Journal/Newspaper |
author |
Agosta, Cécile Amory, Charles Kittel, Christoph Orsi, Anais Favier, Vincent Gallée, Hubert van den Broeke, Michiel R. Lenearts, Jan T. M. van Wessem, Jan Melchior van de Berg, Willem Jan Fettweis, Xavier |
author_facet |
Agosta, Cécile Amory, Charles Kittel, Christoph Orsi, Anais Favier, Vincent Gallée, Hubert van den Broeke, Michiel R. Lenearts, Jan T. M. van Wessem, Jan Melchior van de Berg, Willem Jan Fettweis, Xavier |
author_sort |
Agosta, Cécile |
title |
Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
title_short |
Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
title_full |
Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
title_fullStr |
Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
title_full_unstemmed |
Estimation of the Antarctic surface mass balance using the regional climate model MAR (1979–2015) and identification of dominant processes |
title_sort |
estimation of the antarctic surface mass balance using the regional climate model mar (1979–2015) and identification of dominant processes |
publisher |
Copernicus Group |
publishDate |
2019 |
url |
https://orbi.uliege.be/handle/2268/232308 https://orbi.uliege.be/bitstream/2268/232308/1/tc-13-281-2019.pdf https://doi.org/10.5194/tc-13-281-2019 |
genre |
Antarc* Antarctic Ice Sheet The Cryosphere |
genre_facet |
Antarc* Antarctic Ice Sheet The Cryosphere |
op_source |
The Cryosphere (2019-01-29) |
op_relation |
urn:issn:1994-0416 urn:issn:1994-0424 https://orbi.uliege.be/handle/2268/232308 info:hdl:2268/232308 https://orbi.uliege.be/bitstream/2268/232308/1/tc-13-281-2019.pdf doi:10.5194/tc-13-281-2019 scopus-id:2-s2.0-85060861641 |
op_rights |
open access http://purl.org/coar/access_right/c_abf2 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-13-281-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
1 |
container_start_page |
281 |
op_container_end_page |
296 |
_version_ |
1796933792648134656 |