Recurring dynamically induced thinning during 1985-2010 on Upernavik Isstrøm, West Greenland
Many glaciers along the southeast and northwest coasts of Greenland have accelerated, increasing the ice sheet’s contribution to global sea-level rise. Here, we map elevation changes on Upernavik Isstrøm (UI), West Greenland, during 2003-2009 using high-resolution Ice, Cloud and land Elevation Satel...
Published in: | Journal of Geophysical Research: Earth Surface |
---|---|
Main Authors: | , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2013
|
Subjects: | |
Online Access: | https://curis.ku.dk/portal/da/publications/recurring-dynamically-induced-thinning-during-19852010-on-upernavik-isstroem-west-greenland(a01a5598-3138-4f98-8c48-bd59d170d0fd).html https://doi.org/10.1029/2012JF002481 |
Summary: | Many glaciers along the southeast and northwest coasts of Greenland have accelerated, increasing the ice sheet’s contribution to global sea-level rise. Here, we map elevation changes on Upernavik Isstrøm (UI), West Greenland, during 2003-2009 using high-resolution Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data supplemented with altimeter surveys from NASA’s Airborne Topographic Mapper (ATM) during 2002-2010. To assess thinning prior to 2002, we analyze aerial photographs from 1985. We document at least two distinct periods of dynamically-induced ice loss during 1985-2010 characterized by a rapid retreat of the calving front, increased ice speed and lowering of the ice surface. The first period occurred prior to 1991, while the latter occurred during 2005-2009. Analyses of air and sea surface temperature suggest a combination of relatively warm air and ocean water as a potential trigger for the dynamically-induced ice loss. We estimate a total catchment-wide ice mass loss of UI caused by the two events of 72.3 +/- 15.8 Giga-ton during 1985-2010, while the total melt induced ice mass loss during this same period is 19.8 +/ 2.8 Gt. Thus, 79 % of the total ice mass loss of the UI catchment was caused by ice dynamics, indicating the importance of including dynamically-induced ice loss in the total mass change budget of the Greenland ice sheet. |
---|