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A 70-kyr sea surface temperature record off southern Chile
(Ocean Drilling Program Site 1233)
Paleoceanography
Vol. 20, PA4009, doi:10.1029/2004PA001146, October 2005
Jérôme Kaiser1, Frank Lamy2, and Dierk Hebbeln1
1
Deutsche Forschung Gemeinschaft
Research Center Ocean Margins
University of Bremen
Leobener Strasse
28359 Bremen, Germany
2
GeoForschungsZentrum-Potsdam
Telegrafenberg
14473 Potsdam, Germany.
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ABSTRACT:
We present the first high-resolution alkenone-derived sea surface
temperature (SST) reconstruction in the southeast Pacific (Ocean
Drilling Program Site 1233) covering the major part of the last
glacial period and the Holocene. The record shows a clear
millennial-scale pattern that is very similar to climate
fluctuations observed in Antarctic ice cores, suggesting that
the Southern Hemisphere high-latitude climate changes extended into
the midlatitudes, involving simultaneous changes in air temperatures
over Antarctica, sea ice extent, extension of the Antarctic
Circumpolar Current, and westerly atmospheric circulation.
A comparison to other midlatitude surface ocean records suggests
that this "Antarctic" millennial-scale pattern was probably a
hemisphere-wide phenomenon. In addition, we performed SST gradient
reconstructions over the complete latitudinal range of the Pacific
Eastern Boundary Current System for different time intervals during
the last 70 kyr. The main results suggest an equatorward displaced
subtropical gyre circulation during marine isotope stages 2 and 4.
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