The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation
Coupled climate–ice sheet simulations have been growing in popularity in recent years. Experiments of this type are however challenging as ice sheets evolve over multi-millennial timescales, which is beyond the practical integration limit of most Earth system models. A common method to increase mode...
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ftcopernicus:oai:publications.copernicus.org:tc62621 2023-05-15T16:39:45+02:00 The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation Lofverstrom, Marcus Liakka, Johan 2019-01-11 application/pdf https://doi.org/10.5194/tc-12-1499-2018 https://tc.copernicus.org/articles/12/1499/2018/ eng eng doi:10.5194/tc-12-1499-2018 https://tc.copernicus.org/articles/12/1499/2018/ eISSN: 1994-0424 Text 2019 ftcopernicus https://doi.org/10.5194/tc-12-1499-2018 2020-07-20T16:23:19Z Coupled climate–ice sheet simulations have been growing in popularity in recent years. Experiments of this type are however challenging as ice sheets evolve over multi-millennial timescales, which is beyond the practical integration limit of most Earth system models. A common method to increase model throughput is to trade resolution for computational efficiency (compromise accuracy for speed). Here we analyze how the resolution of an atmospheric general circulation model (AGCM) influences the simulation quality in a stand-alone ice sheet model. Four identical AGCM simulations of the Last Glacial Maximum (LGM) were run at different horizontal resolutions: T85 (1.4 ∘ ), T42 (2.8 ∘ ), T31 (3.8 ∘ ), and T21 (5.6 ∘ ). These simulations were subsequently used as forcing of an ice sheet model. While the T85 climate forcing reproduces the LGM ice sheets to a high accuracy, the intermediate resolution cases (T42 and T31) fail to build the Eurasian ice sheet. The T21 case fails in both Eurasia and North America. Sensitivity experiments using different surface mass balance parameterizations improve the simulations of the Eurasian ice sheet in the T42 case, but the compromise is a substantial ice buildup in Siberia. The T31 and T21 cases do not improve in the same way in Eurasia, though the latter simulates the continent-wide Laurentide ice sheet in North America. The difficulty to reproduce the LGM ice sheets in the T21 case is in broad agreement with previous studies using low-resolution atmospheric models, and is caused by a substantial deterioration of the model climate between the T31 and T21 resolutions. It is speculated that this deficiency may demonstrate a fundamental problem with using low-resolution atmospheric models in these types of experiments. Text Ice Sheet Siberia Copernicus Publications: E-Journals The Cryosphere 12 4 1499 1510 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
Coupled climate–ice sheet simulations have been growing in popularity in recent years. Experiments of this type are however challenging as ice sheets evolve over multi-millennial timescales, which is beyond the practical integration limit of most Earth system models. A common method to increase model throughput is to trade resolution for computational efficiency (compromise accuracy for speed). Here we analyze how the resolution of an atmospheric general circulation model (AGCM) influences the simulation quality in a stand-alone ice sheet model. Four identical AGCM simulations of the Last Glacial Maximum (LGM) were run at different horizontal resolutions: T85 (1.4 ∘ ), T42 (2.8 ∘ ), T31 (3.8 ∘ ), and T21 (5.6 ∘ ). These simulations were subsequently used as forcing of an ice sheet model. While the T85 climate forcing reproduces the LGM ice sheets to a high accuracy, the intermediate resolution cases (T42 and T31) fail to build the Eurasian ice sheet. The T21 case fails in both Eurasia and North America. Sensitivity experiments using different surface mass balance parameterizations improve the simulations of the Eurasian ice sheet in the T42 case, but the compromise is a substantial ice buildup in Siberia. The T31 and T21 cases do not improve in the same way in Eurasia, though the latter simulates the continent-wide Laurentide ice sheet in North America. The difficulty to reproduce the LGM ice sheets in the T21 case is in broad agreement with previous studies using low-resolution atmospheric models, and is caused by a substantial deterioration of the model climate between the T31 and T21 resolutions. It is speculated that this deficiency may demonstrate a fundamental problem with using low-resolution atmospheric models in these types of experiments. |
format |
Text |
author |
Lofverstrom, Marcus Liakka, Johan |
spellingShingle |
Lofverstrom, Marcus Liakka, Johan The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
author_facet |
Lofverstrom, Marcus Liakka, Johan |
author_sort |
Lofverstrom, Marcus |
title |
The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
title_short |
The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
title_full |
The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
title_fullStr |
The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
title_full_unstemmed |
The influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
title_sort |
influence of atmospheric grid resolution in a climate model-forced ice sheet simulation |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-12-1499-2018 https://tc.copernicus.org/articles/12/1499/2018/ |
genre |
Ice Sheet Siberia |
genre_facet |
Ice Sheet Siberia |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-12-1499-2018 https://tc.copernicus.org/articles/12/1499/2018/ |
op_doi |
https://doi.org/10.5194/tc-12-1499-2018 |
container_title |
The Cryosphere |
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12 |
container_issue |
4 |
container_start_page |
1499 |
op_container_end_page |
1510 |
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1766030089330360320 |