What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates
We compare the performance of five different regional climate models (RCMs) (COSMO-CLM 2 , HIRHAM5, MAR3.10, MetUM, and RACMO2.3p2), forced by ERA-Interim reanalysis, in simulating the near-surface climate and surface mass balance (SMB) of Antarctica. All models simulate Antarctic climate well when...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , , , , , , , , , , , , , |
Format: | Text |
Language: | English |
Published: |
2021
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-15-3751-2021 https://tc.copernicus.org/articles/15/3751/2021/ |
id |
ftcopernicus:oai:publications.copernicus.org:tc82789 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:tc82789 2023-05-15T14:02:17+02:00 What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates Mottram, Ruth Hansen, Nicolaj Kittel, Christoph Wessem, J. Melchior Agosta, Cécile Amory, Charles Boberg, Fredrik Berg, Willem Jan Fettweis, Xavier Gossart, Alexandra Lipzig, Nicole P. M. Meijgaard, Erik Orr, Andrew Phillips, Tony Webster, Stuart Simonsen, Sebastian B. Souverijns, Niels 2021-08-17 application/pdf https://doi.org/10.5194/tc-15-3751-2021 https://tc.copernicus.org/articles/15/3751/2021/ eng eng doi:10.5194/tc-15-3751-2021 https://tc.copernicus.org/articles/15/3751/2021/ eISSN: 1994-0424 Text 2021 ftcopernicus https://doi.org/10.5194/tc-15-3751-2021 2021-08-23T16:22:29Z We compare the performance of five different regional climate models (RCMs) (COSMO-CLM 2 , HIRHAM5, MAR3.10, MetUM, and RACMO2.3p2), forced by ERA-Interim reanalysis, in simulating the near-surface climate and surface mass balance (SMB) of Antarctica. All models simulate Antarctic climate well when compared with daily observed temperature and pressure, with nudged models matching daily observations slightly better than free-running models. The ensemble mean annual SMB over the Antarctic ice sheet (AIS) including ice shelves is 2329±94 Gt yr −1 over the common 1987–2015 period covered by all models. There is large interannual variability, consistent between models due to variability in the driving ERA-Interim reanalysis. Mean annual SMB is sensitive to the chosen period; over our 30-year climatological mean period (1980 to 2010), the ensemble mean is 2483 Gt yr −1 . However, individual model estimates vary from 1961±70 to 2519±118 Gt yr −1 . The largest spatial differences between model SMB estimates are in West Antarctica, the Antarctic Peninsula, and around the Transantarctic Mountains. We find no significant trend in Antarctic SMB over either period. Antarctic ice sheet (AIS) mass loss is currently equivalent to around 0.5 mm yr −1 of global mean sea level rise ( Shepherd et al. , 2020 ) , but our results indicate some uncertainty in the SMB contribution based on RCMs. We compare modelled SMB with a large dataset of observations, which, though biased by undersampling, indicates that many of the biases in SMB are common between models. A drifting-snow scheme improves modelled SMB on ice sheet surface slopes with an elevation between 1000 and 2000 m, where strong katabatic winds form. Different ice masks have a substantial impact on the integrated total SMB and along with model resolution are factored into our analysis. Targeting undersampled regions with high precipitation for observational campaigns will be key to improving future estimates of SMB in Antarctica. Text Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelves West Antarctica Copernicus Publications: E-Journals Antarctic Antarctic Peninsula The Antarctic Transantarctic Mountains West Antarctica The Cryosphere 15 8 3751 3784 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
We compare the performance of five different regional climate models (RCMs) (COSMO-CLM 2 , HIRHAM5, MAR3.10, MetUM, and RACMO2.3p2), forced by ERA-Interim reanalysis, in simulating the near-surface climate and surface mass balance (SMB) of Antarctica. All models simulate Antarctic climate well when compared with daily observed temperature and pressure, with nudged models matching daily observations slightly better than free-running models. The ensemble mean annual SMB over the Antarctic ice sheet (AIS) including ice shelves is 2329±94 Gt yr −1 over the common 1987–2015 period covered by all models. There is large interannual variability, consistent between models due to variability in the driving ERA-Interim reanalysis. Mean annual SMB is sensitive to the chosen period; over our 30-year climatological mean period (1980 to 2010), the ensemble mean is 2483 Gt yr −1 . However, individual model estimates vary from 1961±70 to 2519±118 Gt yr −1 . The largest spatial differences between model SMB estimates are in West Antarctica, the Antarctic Peninsula, and around the Transantarctic Mountains. We find no significant trend in Antarctic SMB over either period. Antarctic ice sheet (AIS) mass loss is currently equivalent to around 0.5 mm yr −1 of global mean sea level rise ( Shepherd et al. , 2020 ) , but our results indicate some uncertainty in the SMB contribution based on RCMs. We compare modelled SMB with a large dataset of observations, which, though biased by undersampling, indicates that many of the biases in SMB are common between models. A drifting-snow scheme improves modelled SMB on ice sheet surface slopes with an elevation between 1000 and 2000 m, where strong katabatic winds form. Different ice masks have a substantial impact on the integrated total SMB and along with model resolution are factored into our analysis. Targeting undersampled regions with high precipitation for observational campaigns will be key to improving future estimates of SMB in Antarctica. |
format |
Text |
author |
Mottram, Ruth Hansen, Nicolaj Kittel, Christoph Wessem, J. Melchior Agosta, Cécile Amory, Charles Boberg, Fredrik Berg, Willem Jan Fettweis, Xavier Gossart, Alexandra Lipzig, Nicole P. M. Meijgaard, Erik Orr, Andrew Phillips, Tony Webster, Stuart Simonsen, Sebastian B. Souverijns, Niels |
spellingShingle |
Mottram, Ruth Hansen, Nicolaj Kittel, Christoph Wessem, J. Melchior Agosta, Cécile Amory, Charles Boberg, Fredrik Berg, Willem Jan Fettweis, Xavier Gossart, Alexandra Lipzig, Nicole P. M. Meijgaard, Erik Orr, Andrew Phillips, Tony Webster, Stuart Simonsen, Sebastian B. Souverijns, Niels What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
author_facet |
Mottram, Ruth Hansen, Nicolaj Kittel, Christoph Wessem, J. Melchior Agosta, Cécile Amory, Charles Boberg, Fredrik Berg, Willem Jan Fettweis, Xavier Gossart, Alexandra Lipzig, Nicole P. M. Meijgaard, Erik Orr, Andrew Phillips, Tony Webster, Stuart Simonsen, Sebastian B. Souverijns, Niels |
author_sort |
Mottram, Ruth |
title |
What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
title_short |
What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
title_full |
What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
title_fullStr |
What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
title_full_unstemmed |
What is the surface mass balance of Antarctica? An intercomparison of regional climate model estimates |
title_sort |
what is the surface mass balance of antarctica? an intercomparison of regional climate model estimates |
publishDate |
2021 |
url |
https://doi.org/10.5194/tc-15-3751-2021 https://tc.copernicus.org/articles/15/3751/2021/ |
geographic |
Antarctic Antarctic Peninsula The Antarctic Transantarctic Mountains West Antarctica |
geographic_facet |
Antarctic Antarctic Peninsula The Antarctic Transantarctic Mountains West Antarctica |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelves West Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Ice Sheet Ice Shelves West Antarctica |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-15-3751-2021 https://tc.copernicus.org/articles/15/3751/2021/ |
op_doi |
https://doi.org/10.5194/tc-15-3751-2021 |
container_title |
The Cryosphere |
container_volume |
15 |
container_issue |
8 |
container_start_page |
3751 |
op_container_end_page |
3784 |
_version_ |
1766272457642082304 |