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...
Published in: | Climate of the Past |
---|---|
Main Authors: | , |
Format: | Text |
Language: | English |
Published: |
2019
|
Subjects: | |
Online Access: | https://doi.org/10.5194/cp-14-887-2018 https://cp.copernicus.org/articles/14/887/2018/ |
id |
ftcopernicus:oai:publications.copernicus.org:cp67164 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:cp67164 2023-05-15T13:11:29+02:00 Arctic warming induced by the Laurentide Ice Sheet topography Liakka, Johan Lofverstrom, Marcus 2019-04-16 application/pdf https://doi.org/10.5194/cp-14-887-2018 https://cp.copernicus.org/articles/14/887/2018/ eng eng doi:10.5194/cp-14-887-2018 https://cp.copernicus.org/articles/14/887/2018/ eISSN: 1814-9332 Text 2019 ftcopernicus https://doi.org/10.5194/cp-14-887-2018 2020-07-20T16:23:13Z 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; ∼ 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 ∘ C per km of elevation increase, or about 6.5 ∘ 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. Text albedo Arctic Ice Sheet Copernicus Publications: E-Journals Arctic Climate of the Past 14 6 887 900 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
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; ∼ 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 ∘ C per km of elevation increase, or about 6.5 ∘ 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. |
format |
Text |
author |
Liakka, Johan Lofverstrom, Marcus |
spellingShingle |
Liakka, Johan Lofverstrom, Marcus Arctic warming induced by the Laurentide Ice Sheet topography |
author_facet |
Liakka, Johan Lofverstrom, Marcus |
author_sort |
Liakka, Johan |
title |
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 |
2019 |
url |
https://doi.org/10.5194/cp-14-887-2018 https://cp.copernicus.org/articles/14/887/2018/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
albedo Arctic Ice Sheet |
genre_facet |
albedo Arctic Ice Sheet |
op_source |
eISSN: 1814-9332 |
op_relation |
doi:10.5194/cp-14-887-2018 https://cp.copernicus.org/articles/14/887/2018/ |
op_doi |
https://doi.org/10.5194/cp-14-887-2018 |
container_title |
Climate of the Past |
container_volume |
14 |
container_issue |
6 |
container_start_page |
887 |
op_container_end_page |
900 |
_version_ |
1766247639395860480 |