Collapsing ice shelves and increased calving of large icebergs in Greenland and Antarctica are symptoms of rapidly changing ice sheets and rising seas. The rapidity of these changes has come as a surprise, revealing our limited understanding of how ice sheets respond to a warming climate. One major obstacle to understand these changes, and project future ones, is the lack of measurements from the Achilles’ heel of glaciers: the marine edge. A second, related one is the need to account for the complexity of interactions between the glaciers and the ocean in models used for projections. In this lecture, I show how both can be overcome through a collaborative, team science effort which spans across the natural sciences and engineering and includes local, indigenous knowledge. This team science has allowed us to probe the edge of massive calving glaciers in iceberg-choked fjords in Greenland using instruments deployed from helicopters, icebreakers, fishing vessels, snow mobiles and autonomous vehicles. We have documented the intrusions of warm, Gulf Stream water into the fjords and found that the ensuing melting of the glaciers is enhanced by muddy plumes of surface melt, released thousands of feet below the sea surface. These limited measurements, complemented by theoretical, laboratory and numerical modeling, have then been used to improve the climate models used for sea level rise predictions in a large, international collaborative effort. The lecture will focus on this journey – from the edge of glaciers to global predictive models.

Registration will be available Sept 1.