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

这项研究项目测试了这样一种假设：过去的突然变化，如年轻的仙女木冷事件、较老的仙女木冷期、阿勒罗德内部的冷期和8.2ka的冷却事件，以及未来与人类改变大气有关的突然变化，可能会立即在“方差放大”之前，将系统驱动到临界点，迎来新的稳态气候条件。研究人员的目标是使用大湖区的年轮作为高分辨率气候指标来测试冰川消融期间的这种方差放大。研究人员将大湖区作为研究方差放大的目标，因为它距离北大西洋足够近，与在那里产生的气候事件有很强的远程联系，而大湖区的事件本身可能引发了一些半球范围的气候偏离。主要的更广泛的影响包括支持该项目的本科生，并创建一个树状气候学和相关科学的夏季短期课程。

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.