Abrupt change in tropical African climate linked to the bipolar seesaw over the past 55,000 years

作者：Brown E T^*; Johnson T C; Scholz C A; Cohen A S; King J W

来源：Geophysical Research Letters, 2007, 34(20): L20702.

DOI：10.1029/2007GL031240

The tropics play a major role in global climate dynamics, and are vulnerable to future climate change. We present a record of East African climate since 55 ka, preserved in Lake Malawi sediments, that indicates rapid shifts between discrete climate modes related to abrupt warming (D-O) events observed in Greenland. Although the timing of the Malawi events cannot be determined exactly, our age model implies that they occur prior to their Greenland counterparts, consistent with southward excursions of the Intertropical Convergence Zone during Greenland stadials. The magnitude of each of the events recorded in Malawi sediments corresponds to the scale of the subsequent Greenland warming. This suggests that a tropical component of climate sets a template for abrupt high northern latitude climate fluctuations associated with the bipolar seesaw.

• 出版日期2007-10-18