Nearly Synchronous Climate Change in the Northern Hemisphere during the Last Glacial Termination

Authors

Larry V. Benson, University of Colorado at BoulderFollow
James Burdett, Cornell Laboratory for Stable Isotope Analysis
Steve Lund, University of Southern CaliforniaFollow
Michaele Kashgarian, Lawrence Livermore National Laboratory
Scott Mensing, University of Nevada

Document Type

Article

Date of this Version

1997

Citation

Nature (July 1997) 388

Comments

United States government work

Abstract

The climate of the North Atlantic region underwent a series of abrupt cold/warm oscillations when the ice sheets of the Northern Hemisphere retreated during the last glacial termination (17,700–11,500 years ago). Evidence for these oscillations, which are recorded in European terrestrial sediments as the Oldest Dryas/Bølling/ Older Dryas/Allerød/Younger Dryas vegetational sequence, has been found in Greenland ice cores. The geographical extent of many of these oscillations is not well known, but the last major cold event (the Younger Dryas) seems to have been global in extent. Here we present evidence of four major oscillations in the hydrological balance of the Owens basin, California, that occurred during the last glacial termination. Dry events in western North America occurred at approximately the same time as cold events recorded in Greenland ice, with transitions between climate regimes in the two regions taking place within a few hundred years of each other. Our observations thus support recent climate simulations which indicate that cooling of the North Atlantic Ocean results in cooling of the North Pacific Ocean which, in turn, leads to a drier climate in western North America.