HR: 14:55h
AN: C13A-06 INVITED    [Abstracts]
TI: New States of Behavior: Current Status of Outlet Glaciers in Southeast Greenland and the Potential for Similar Changes Elsewhere
AU: * Stearns, L A
EM: leigh.stearns@maine.edu
AF: Climate Change Institute, University of Maine, 5790 Bryand Global Sciences Center, Orono, ME 04469, United States
AU: Hamilton, G S
EM: gordon.hamilton@maine.edu
AF: Climate Change Institute, University of Maine, 5790 Bryand Global Sciences Center, Orono, ME 04469, United States
AB: The Greenland Ice Sheet's contribution to sea level has doubled in the last 5 years, largely as a consequence of increased ice discharge through outlet glaciers in southeast Greenland. An analysis of satellite remote sensing data shows that just two glaciers, Helheim and Kangerdlugssuaq, might account for ~10% of the observed rise in global sea level since 2001. These two glaciers progressively thinned before entering phases of terminus retreat, rapid acceleration, and faster thinning. After periods of reaching peak speeds 2-3 times faster than historical ('normal') values, both glaciers have decelerated slightly, but are still sustaining speeds far in excess of normal conditions. We speculate that these faster flow speeds represent a new long-term state of behavior which, while not as dramatic as the short-lived periods of peak speeds, have important implications for the rate of sea level rise. Other outlet glaciers in Greenland might be close to similar switches in flow regime. We use existing data to examine which glaciers are the next most likely to change, and describe some of the warning signs we might use to predict imminent changes.
DE: 0726 Ice sheets
DE: 0730 Ice streams
DE: 0758 Remote sensing
DE: 1641 Sea level change (1222, 1225, 4556)
DE: 9315 Arctic region (0718, 4207)
SC: Cryosphere [C]
MN: 2007 Fall Meeting