Recurring dynamically induced thinning during 1985-2010 on Upernavik Isstrøm, West Greenland
Research output: Contribution to journal › Journal article › Research › peer-review
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.
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.
Original language | English |
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Journal | Journal of Geophysical Research: Earth Surface |
Volume | 118 |
Issue number | 1 |
Pages (from-to) | 111–121 |
Number of pages | 11 |
ISSN | 2169-8953 |
DOIs | |
Publication status | Published - Mar 2013 |
ID: 41993177