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ABSTRACT: Palaeoclimate studies have revealed the general high-frequency instability of Late Pleistocene climate - for example, the so-called Dansgaard-Oeschger and Heinrich events - on timescales of a few millennia, centuries or even decades. Here we present evidence for a general relationship between low-latitude monsoonal climate variability and the rapid temperature fluctuations of high northern latitudes that are recorded in the Greenland ice records. Sediment cores from the northeastern Arabian Sea show laminated, organic-carbon-rich bands, reflecting strong monsoon-induced biological productivity, that correlate with the mild interstadial climate events in the northern North Atlantic region. In contrast, periods of lowered southwest monsoonal intensity, indicated by bioturbated, organic-carbon-poor bands, are associated with intervals of high-latitude atmospheric cooling and the injection of melt water into the North Atlantic basin. Our records suggest that Dansgaard-Oeschger and Heinrich events are strongly expressed in low-latitude (monsoonal) climate variability, suggesting the importance of common forcing agents such as atmospheric moisture and other greenhouse gases. |
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| DATA: Download the Data from the WDC Paleo Archive. |
| DISCUSSION: Both the total organic carbon (TOC, Figure 2) and the stable oxygen isotope and sonic velocity (Figure 3) from the Arabian Sea cores show the broad geographic impact of the abrupt climate changes during the last glacial period. These record reveals climatic impacts in China synchronous with the North Atlantic Ocean Heinrich events as seen in ice cores from Greenland . The Greenland Ice Sheet Project Two (GISP2) core data is also available on the WDC Paleo website.
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Contact Us National Oceanic and Atmospheric Administration 10 May 2004
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