Response of precipitation over Greenland and the adjacent ocean to North Pacific warm spells during Dansgaard-Oeschger stadials
Palaeoceanographic reconstructions from the North Atlantic indicate massive ice breakouts from East Greenland near the onset of cold Dansgaard-Oeschger (D-O) stadials. In contrast to these coolings in the North Atlantic area, a new sea-surface temperature record reveals concomitant warm spells in th...
Published in: | Terra Nova |
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Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2002
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Subjects: | |
Online Access: | http://hdl.handle.net/11858/00-001M-0000-0012-02E7-2 http://hdl.handle.net/21.11116/0000-000B-7BC4-E |
Summary: | Palaeoceanographic reconstructions from the North Atlantic indicate massive ice breakouts from East Greenland near the onset of cold Dansgaard-Oeschger (D-O) stadials. In contrast to these coolings in the North Atlantic area, a new sea-surface temperature record reveals concomitant warm spells in the northern North Pacific. A sensitivity experiment with an atmospheric general circulation model is used to test the potential impact of sea-surface warmings by 3.5 degreesC in the North Pacific, on top of otherwise cold stadial climate conditions, on the precipitation regime over the Northern Hemisphere ice sheets. The model predicts a maximum response over East Greenland and the Greenland Sea, where a 40% increase in net annual snow accumulation occurs. This remote effect of North Pacific warm spells on the East Greenland snow-accumulation rate may play an important role in generating D-O cycles by rebuilding the ice lost during ice breakouts. In addition, the increased precipitation over the Greenland Sea may help to sustain the D-O stadial climate state. |
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