Equatorward shift of the subarctic boundary in the northwestern Pacific during the last deglaciation

Abstract

We have generated a high-resolution record of alkenone sea surface temperature (SST) between 10-24 ka from Core MD01-2421 off central Japan, in the northwestern Pacific. The cooling by 5°C from 21 ka to 12.8 ka implies the equatorward shift of the subarctic boundary in the northwestern Pacific by ∼2.8° in latitude. This shift was a result of the stronger summer Okhotsk High. The Okhotsk High was likely enhanced by the combined effects of El Niño-like conditions in the tropical Pacific and the heating of the land surface of northeastern Siberia. Copyright 2005 by the American Geophysical Union.