Abstract ATM-9870886 Alley, Richard B. Pennsylvania State University Title: Laurentide Thermal Instability Modeling This award supports collaborative research at the University of Chicago and Pennsylvania State University designed to develop a suite of finite-element ice-sheet models to study the role of ice sheets in millennial-scale climate change observed in the geologic record. The main focus of the research will be to understand how thermal instability (i.e., switching from frozen to melted conditions at the glacial bed) leads to ice-stream and ice-lobe activity that interacts strongly with the surrounding environment, either as an amplifier of externally forced climate change or as an instigator of climate change in the atmosphere and ocean. Model experiments will attempt to resolve the controversy as to whether the cause of Heinrich events and Bond/Lotti events is this thermal triggering mechanism or is the climate cooling seen in the Greenland ice-core records.
