Impact of the North American ice-sheet orography on the Last Glacial Maximum eddies and snowfall
International audience The present work evaluates the influence of the North American ice-sheet orography on the Last Glacial Maximum (LGM, 21,000 years ago) atmospheric circulation and snowfall in the northern mid-latitudes, focusing on the North Atlantic sector. Three Atmospheric General Circulati...
Published in: | Geophysical Research Letters |
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Main Authors: | , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2000
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Subjects: | |
Online Access: | https://hal.science/hal-02930149 https://hal.science/hal-02930149/document https://hal.science/hal-02930149/file/1999GL011274.pdf https://doi.org/10.1029/1999GL011274 |
Summary: | International audience The present work evaluates the influence of the North American ice-sheet orography on the Last Glacial Maximum (LGM, 21,000 years ago) atmospheric circulation and snowfall in the northern mid-latitudes, focusing on the North Atlantic sector. Three Atmospheric General Circulation Model experiments are analysed: a control and an LGM climate simulation, and an LGM run with "fiat" ice-sheets over northern North America. This ice-sheet orography affects lee-cyclogenesis over North America and forces differences in stationary waves and therefore in the baroclinicity of the mean flow. As a result, the Atlantic storm-track is reinforced in the "fiat ice-sheet" experiment compared to the LGM one. This, in turn, has a profound impact on snowfall over northern Europe, implying a coupling between the two ice-sheets. |
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