Response of the Labrador Sea to insolation forcing during the most recent five interglaciations

The Labrador Sea is connected to the global climate system via both winter water column convection and interactions with Greenland Ice Sheet. A chronology of Labrador Sea temperatures is therefore necessary to understand larger scale North Atlantic climate. Here, we report northeast Labrador Sea near-surface ocean temperatures for the most recent five interglaciations. We estimate temperatures using planktic foraminiferal Mg/Ca from Neogloboquadrina pachyderma (sinistral), picked from Eirik Drift sediment core MD99-2227, located to the south of Greenland. Preliminary data from Marine Isotope Stages (MIS) 1 and 5e suggest that Labrador Sea near-surface ocean temperatures did not correlate proportionately with boreal summer insolation, with MIS 5e temperatures being no warmer than MIS 1. To investigate whether this relationship between temperature and insolation existed for other interglaciations, we will examine Mg/Ca-derived temperatures for MIS 7, 9, and 11, which represent a range in boreal summer insolation values. This record will improve our ability to predict the response of the Labrador Sea to future increases in radiative forcing and attendant melting of the Greenland Ice Sheet.