Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation
Here, we analyze modeling results of the North Atlantic atmospheric winter circulation from a transient climate simulation over the last 21,000 years. In agreement with previous studies, we find that the midlatitude jet stream assumes a strong, stable, and zonal disposition so long as the North Amer...
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Online Access: | http://www.osti.gov/servlets/purl/1473897 https://www.osti.gov/biblio/1473897 https://doi.org/10.1002/2017GL074274 |
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ftosti:oai:osti.gov:1473897 2023-07-30T04:04:12+02:00 Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation Löfverström, Marcus Lora, Juan M. 2022-01-03 application/pdf http://www.osti.gov/servlets/purl/1473897 https://www.osti.gov/biblio/1473897 https://doi.org/10.1002/2017GL074274 unknown http://www.osti.gov/servlets/purl/1473897 https://www.osti.gov/biblio/1473897 https://doi.org/10.1002/2017GL074274 doi:10.1002/2017GL074274 54 ENVIRONMENTAL SCIENCES 2022 ftosti https://doi.org/10.1002/2017GL074274 2023-07-11T09:29:08Z Here, we analyze modeling results of the North Atlantic atmospheric winter circulation from a transient climate simulation over the last 21,000 years. In agreement with previous studies, we find that the midlatitude jet stream assumes a strong, stable, and zonal disposition so long as the North American ice sheets remain in their continent-wide Last Glacial Maximum (LGM) configuration. However, when the Laurentide ice sheet (LIS) and Cordilleran ice sheet separate (~14,000 years ago), the jet stream abruptly changes to a tilted circulation regime, similar to modern. The proposed explanation is that the dominant stationary wave source in the North Atlantic sector changes from the LIS to the Cordilleran mountain range during the saddle collapse. As long as the LIS dominates, the circulation retains the zonal LGM state characterized by prevalent stationary wave reflection in the subtropical North Atlantic. When the Cordillera takes over, the circulation acquires its modern disposition with a weak and meridionally tilted jet stream and storm track. Other/Unknown Material Ice Sheet North Atlantic SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Geophysical Research Letters 44 15 8047 8055 |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
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54 ENVIRONMENTAL SCIENCES |
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54 ENVIRONMENTAL SCIENCES Löfverström, Marcus Lora, Juan M. Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
Here, we analyze modeling results of the North Atlantic atmospheric winter circulation from a transient climate simulation over the last 21,000 years. In agreement with previous studies, we find that the midlatitude jet stream assumes a strong, stable, and zonal disposition so long as the North American ice sheets remain in their continent-wide Last Glacial Maximum (LGM) configuration. However, when the Laurentide ice sheet (LIS) and Cordilleran ice sheet separate (~14,000 years ago), the jet stream abruptly changes to a tilted circulation regime, similar to modern. The proposed explanation is that the dominant stationary wave source in the North Atlantic sector changes from the LIS to the Cordilleran mountain range during the saddle collapse. As long as the LIS dominates, the circulation retains the zonal LGM state characterized by prevalent stationary wave reflection in the subtropical North Atlantic. When the Cordillera takes over, the circulation acquires its modern disposition with a weak and meridionally tilted jet stream and storm track. |
author |
Löfverström, Marcus Lora, Juan M. |
author_facet |
Löfverström, Marcus Lora, Juan M. |
author_sort |
Löfverström, Marcus |
title |
Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
title_short |
Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
title_full |
Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
title_fullStr |
Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
title_full_unstemmed |
Abrupt regime shifts in the North Atlantic atmospheric circulation over the last deglaciation |
title_sort |
abrupt regime shifts in the north atlantic atmospheric circulation over the last deglaciation |
publishDate |
2022 |
url |
http://www.osti.gov/servlets/purl/1473897 https://www.osti.gov/biblio/1473897 https://doi.org/10.1002/2017GL074274 |
genre |
Ice Sheet North Atlantic |
genre_facet |
Ice Sheet North Atlantic |
op_relation |
http://www.osti.gov/servlets/purl/1473897 https://www.osti.gov/biblio/1473897 https://doi.org/10.1002/2017GL074274 doi:10.1002/2017GL074274 |
op_doi |
https://doi.org/10.1002/2017GL074274 |
container_title |
Geophysical Research Letters |
container_volume |
44 |
container_issue |
15 |
container_start_page |
8047 |
op_container_end_page |
8055 |
_version_ |
1772815439605268480 |