This research project tests the hypothesis that past abrupt changes like the Younger Dryas cold event, the Older Dryas cold period, Intra-Allerød cold period, and the 8.2 ka cooling event, as well as future abrupt changes related to human alteration of the atmosphere, may be immediately preceded by "variance amplification" that drives the system to tipping points that usher in the new steady-state climate conditions. The researchers aim to test for such variance amplification during deglaciation using tree-rings from the Great Lakes region as high-resolution climate proxies. The Great Lakes region is targeted by the researchers for investigating variance amplification because it is close enough to the North Atlantic to be strongly teleconnected to climate events spawned there and events in the Great Lake region itself may have triggered some of these hemisphere-wide climate excursions. The primary broader impacts involve supporting undergraduate students in the project and creating a summer short course in dendroclimatology and related sciences.
P2C2: Flickering Climate: Assessment of the Non-Stationary Environment in the Great Lakes Area, 14 ka to 8 ka BP- A Time of Rising Human Population and Mega-Fauna Extinction