Testing Arctic Ice Sheet Sensitivity to Abrupt Climate Change

An intensive field-based research program capitalizing on our ability to reconstruct ice sheet change using high-precision beryllium-10 dating. We are interested if prominent moraine systems marking former ice extents in West Greenland and Baffin Island record the synchronous advance of the Greenland and Laurentide ice sheets driven by the abrupt cooling events 9.3 and 8.2 thousand years ago. Pilot data reveal that portions of the ice sheet margin that are in contact with the surrounding ocean are able to respond rapidly to a short-lived climate perturbation. To test whether these documented changes were restricted to solely the most sensitive marine-terminating ice sheet sectors, or whether ice sheets are capable of a larger scale response to centennial-scale climate change, well-constrained chronologies of ice sheet change are needed from other regions. We are 1) establishing how land-terminating regions of ice sheets, which are more representative of broader ice sheet margins, respond to abrupt climate change, 2) evaluating the role that oceanic forcing plays in modulating ice sheet response to short-lived climate perturbations, and 3) reconstruct the early Holocene behavior of mountain glacier systems (a proxy for summertime temperature) to evaluate what climatic conditions influenced the ice sheets.

This project has been supported by funding from: