The Greenland Ice Sheet's contribution to sea-level rise more than doubled over the last two decades due to increased melting and to the widespread acceleration of outlet glaciers around Greenland. One of the mechanisms scientists believe may have triggered this acceleration are changes in ocean circulation in the North Atlantic which are delivering larger amounts of subtropical waters to the high latitudes. As these waters reach the glaciers, they can result in increased submarine melting thus modifying the force balance at the edge of the glaciers – potentially driving glacier acceleration. Our knowledge of the properties of the ocean waters reaching Greenland's glaciers and our understanding of the oceanic, atmospheric and glaciogical mechanisms that control their variability, however, is presently very limited. Furthermore, the physics of ice sheet/ocean interactions are typically absent or crudely represented in ice sheet, glacier and climate models. Thus more and longer term measurements from the ice/ocean boundary as well as process oriented modeling studies are needed to address these issues and improve our ability to interpret past and predict future ice sheet variability. As part of this effort, my team and I have been collecting synoptic and moored data at the edge of several major outlet glaciers in East Greenland (Helheim, Kangerdlugssuaq and 79 N Glaciers) using local vessels, icebreakers and helicopters. The goal of these measurements is to identify the oceanic processes which control the submarine melt rate and improve our understanding of the relevant dynamics.
Ice Sheet Ocean Interactions around Greenland
Gordon Hamilton – University of Maine
David Sutherland – University of Washington
Ruth Curry – WHOI
Leigh Stearns – University of Kansas
U.S. CLIVAR WORKING GROUP ON ICE SHEET-OCEAN INTERACTIONS IN GREENLAND
The goal of this working group is to foster and promote interaction between the diverse oceanographic, glaciological, atmospheric and climate communities, including modelers and field and data scientists within each community, interested in glacier/ocean interactions around Greenland, to advance understanding of the process and ultimately improve its representation in climate models.
COMMUNITY FEEDBACK REQUESTED by January 15th
The Working Group has drafted a white paper summarizing the state of knowledge and the main questions pertaining to understanding ice sheet/ocean interactions in Greenland and made recommendations on how to move forward. The document is now available for community feedback and can be found at http://griso-wg.org/documents
- Melting of Greenland's glaciers by Atlantic Waters, F. Straneo et al., Annals of Glaciology, under revision.
Last updated: December 15, 2011