Antarctic timing of surface water changes off Chile and Patagonian ice sheet response.
نویسندگان
چکیده
Marine sediments from the Chilean continental margin are used to infer millennial-scale changes in southeast Pacific surface ocean water properties and Patagonian ice sheet extent since the last glacial period. Our data show a clear "Antarctic" timing of sea surface temperature changes, which appear systematically linked to meridional displacements in sea ice, westerly winds, and the circumpolar current system. Proxy data for ice sheet changes show a similar pattern as oceanographic variations offshore, but reveal a variable glacier-response time of up to approximately 1000 years, which may explain some of the current discrepancies among terrestrial records in southern South America.
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عنوان ژورنال:
- Science
دوره 304 5679 شماره
صفحات -
تاریخ انتشار 2004