Large-scale instabilities of the Laurentide ice sheet simulated in a fully coupled climate-system model
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چکیده
[1] Heinrich events, related to large-scale surges of the Laurentide ice sheet, represent one of the most dramatic types of abrupt climate change occurring during the last glacial. Here, using a coupled atmosphere-ocean-biosphereice sheet model, we simulate quasi-periodic large-scale surges from the Laurentide ice sheet. The average time between simulated events is about 7,000 yrs, while the surging phase of each event lasts only several hundred years, with a total ice volume discharge corresponding to 5–10 m of sea level rise. In our model the simulated ice surges represent internal oscillations of the ice sheet. At the same time, our results suggest the possibility of a synchronization between instabilities of different ice sheets, as indicated in paleoclimate records.
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تاریخ انتشار 2002