Evolution of the North Atlantic's Climate Over the Last 3000 Years and Comparison with Late MIS 5e

Columbia University, New York NY

Investigators

Abstract

Science Summary: This proposal requests support for a multiproxy study to test the theory that atmospheric cooling beginning about 2000 years ago lead to increased production of North Atlantic Deep Water in the western North Atlantic primarily through an increase in Denmark Strait Overflow water. The sequence of events in the last 2000 years is very similar to events observed at the end of the last interglacial (MIS 5e) and suggests that the increase of deep water production in the western North Atlantic marks the beginning of the end of the current interglacial. This study will include detailed analysis of samples from cores in separate transects to determine sea surface temperature and rates of Holocene and MIS 5e deep water production across the North Atlantic. Proxies to be studied include faunal counts, stable isotope measurements of N. pachyderma (left and right coiling), IRD and IRD petrology. In addition trace element analyses (Cd/Ca, Zn/Ca, and Mg/Ca) will assist and check interpretations based on faunal and stable isotope data.