title: Southern Hemisphere and deep-sea warming led deglacial atmospheric CO2 rise and tropical warming.
abstract: Establishing what caused Earth's largest climatic changes in the past requires a precise knowledge of both the forcing and the regional responses. We determined the chronology of high- and low-latitude climate change at the last glacial termination by radiocarbon dating benthic and planktonic foraminiferal stable isotope and magnesium/calcium records from a marine core collected in the western tropical Pacific. Deep-sea temperatures warmed by approximately 2 degrees C between 19 and 17 thousand years before the present (ky B.P.), leading the rise in atmospheric CO2 and tropical-surface-ocean warming by approximately 1000 years. The cause of this deglacial deep-water warming does not lie within the tropics, nor can its early onset between 19 and 17 ky B.P. be attributed to CO2 forcing. Increasing austral-spring insolation combined with sea-ice albedo feedbacks appear to be the key factors responsible for this warming.
authors: Department of Earth Sciences, University of Southern California, Los Angeles, CA 90089, USA. stott@usc.edu
authors: Lowell
authors: L
authors: Stott
authors: Axel
authors: A
authors: Timmermann
authors: Robert
authors: R
authors: Thunell