RECONSTRUCTING TEMPERATURES DURING THE YOUNGER DRYAS USING A FRESHWATER OSTRACODE TRAINING SET FROM LAKE SEDIMENTS IN THE CANADIAN NORTH

Freshwater ostracode and environmental data from 60 lakes in northern Canada were used to develop a modern training set for paleoenvironmental application. Mean July air temperatures for the southwest Yukon were reconstructed from Upper Fly Lake (61.04°N, 138.09°W, 1326 m.a.s.l.) sediments during the Younger Dryas (12 900 to 11 300 cal yr BP). The modern analogue technique and transfer function approaches indicate that conditions were warm up to 12 000 cal yr BP, followed by cool temperatures from 12 000 to 11 400 cal yr BP. Estimates derived from other proxy data (pollen and chironomids) support these findings, and an alternative method will be applied to the ostracode data to reconstruct climate. These records will then be compared with other paleoclimate evidence from the Yukon and Alaska.