Arctic warming induced by the Laurentide Ice Sheet topography
It is well known that ice sheet-climate feedbacks are essential for realistically simulating the spatiotemporal evolution of continental ice sheets over glacial-interglacial cycles. However, many of these feedbacks are dependent on the ice sheet thickness, which is poorly constrained by proxy data r...
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Language: | English |
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Online Access: | https://doi.org/10.5194/cp-14-887-2018 |
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ftncar:oai:drupal-site.org:articles_21729 2023-09-05T13:11:30+02:00 Arctic warming induced by the Laurentide Ice Sheet topography Liakka, Johan (author) Loefverstrom, Marcus (author) 2018-06-22 https://doi.org/10.5194/cp-14-887-2018 en eng Climate of the Past--Clim. Past--1814-9332 articles:21729 ark:/85065/d7vt1vwj doi:10.5194/cp-14-887-2018 Copyright 2018 Author(s). This work is licensed under a Creative Commons Attribution 4.0 International license. article Text 2018 ftncar https://doi.org/10.5194/cp-14-887-2018 2023-08-14T18:47:42Z It is well known that ice sheet-climate feedbacks are essential for realistically simulating the spatiotemporal evolution of continental ice sheets over glacial-interglacial cycles. However, many of these feedbacks are dependent on the ice sheet thickness, which is poorly constrained by proxy data records. For example, height estimates of the Laurentide Ice Sheet (LIS) topography at the Last Glacial Maximum (LGM; similar to 21 000 years ago) vary by more than 1 km among different ice sheet reconstructions. In order to better constrain the LIS elevation it is therefore important to understand how the mean climate is influenced by elevation discrepancies of this magnitude. Here we use an atmospheric circulation model coupled to a slab-ocean model to analyze the LGM surface temperature response to a broad range of LIS elevations (from 0 to over 4 km). We find that raising the LIS topography induces a widespread surface warming in the Arctic region, amounting to approximately 1.5 degrees C per km of elevation increase, or about 6.5 degrees C for the highest LIS. The warming is attributed to an increased poleward energy flux by atmospheric stationary waves, amplified by surface albedo and water vapor feedbacks, which account for about two-thirds of the total temperature response. These results suggest a strong feedback between continental-scale ice sheets and the Arctic temperatures that may help constrain LIS elevation estimates for the LGM and explain differences in ice distribution between the LGM and earlier glacial periods. Article in Journal/Newspaper albedo Arctic Ice Sheet OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) Arctic Climate of the Past 14 6 887 900 |
institution |
Open Polar |
collection |
OpenSky (NCAR/UCAR - National Center for Atmospheric Research/University Corporation for Atmospheric Research) |
op_collection_id |
ftncar |
language |
English |
description |
It is well known that ice sheet-climate feedbacks are essential for realistically simulating the spatiotemporal evolution of continental ice sheets over glacial-interglacial cycles. However, many of these feedbacks are dependent on the ice sheet thickness, which is poorly constrained by proxy data records. For example, height estimates of the Laurentide Ice Sheet (LIS) topography at the Last Glacial Maximum (LGM; similar to 21 000 years ago) vary by more than 1 km among different ice sheet reconstructions. In order to better constrain the LIS elevation it is therefore important to understand how the mean climate is influenced by elevation discrepancies of this magnitude. Here we use an atmospheric circulation model coupled to a slab-ocean model to analyze the LGM surface temperature response to a broad range of LIS elevations (from 0 to over 4 km). We find that raising the LIS topography induces a widespread surface warming in the Arctic region, amounting to approximately 1.5 degrees C per km of elevation increase, or about 6.5 degrees C for the highest LIS. The warming is attributed to an increased poleward energy flux by atmospheric stationary waves, amplified by surface albedo and water vapor feedbacks, which account for about two-thirds of the total temperature response. These results suggest a strong feedback between continental-scale ice sheets and the Arctic temperatures that may help constrain LIS elevation estimates for the LGM and explain differences in ice distribution between the LGM and earlier glacial periods. |
author2 |
Liakka, Johan (author) Loefverstrom, Marcus (author) |
format |
Article in Journal/Newspaper |
title |
Arctic warming induced by the Laurentide Ice Sheet topography |
spellingShingle |
Arctic warming induced by the Laurentide Ice Sheet topography |
title_short |
Arctic warming induced by the Laurentide Ice Sheet topography |
title_full |
Arctic warming induced by the Laurentide Ice Sheet topography |
title_fullStr |
Arctic warming induced by the Laurentide Ice Sheet topography |
title_full_unstemmed |
Arctic warming induced by the Laurentide Ice Sheet topography |
title_sort |
arctic warming induced by the laurentide ice sheet topography |
publishDate |
2018 |
url |
https://doi.org/10.5194/cp-14-887-2018 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
albedo Arctic Ice Sheet |
genre_facet |
albedo Arctic Ice Sheet |
op_relation |
Climate of the Past--Clim. Past--1814-9332 articles:21729 ark:/85065/d7vt1vwj doi:10.5194/cp-14-887-2018 |
op_rights |
Copyright 2018 Author(s). This work is licensed under a Creative Commons Attribution 4.0 International license. |
op_doi |
https://doi.org/10.5194/cp-14-887-2018 |
container_title |
Climate of the Past |
container_volume |
14 |
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6 |
container_start_page |
887 |
op_container_end_page |
900 |
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1776204944964059136 |