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Published on: July 3, 2016
Greenland Ice Sheet: High-Elevation Balance and Peripheral Thinning.
1Laboratory for Hydrospheric Processes, NASA Goddard Space Flight Center and EG&G Services, Wallops Flight Facility, Building N-159, Wallops Island, VA 23337, USA. Laboratory for Hydrospheric Processes, NASA Goddard Space Flight Center, Building 33, Room A225, Greenbelt, MD 20771, USA.
Science (New York, N.Y.)
|July 21, 2000
Summary
The Greenland Ice Sheet shows regional variations but is balanced above 2000m. Lower elevations, especially near the coast, are thinning rapidly, contributing to sea level rise.
Area of Science:
- Glaciology
- Climate Science
- Earth Observation
Background:
- The Greenland Ice Sheet's mass balance is crucial for understanding global sea level changes.
- Previous studies have provided data on ice sheet dynamics, but comprehensive recent analyses are needed.
Purpose of the Study:
- To analyze the recent mass balance of the Greenland Ice Sheet using combined altimetry data.
- To quantify the net ice loss and its contribution to sea level rise.
Main Methods:
- Coupling aircraft laser-altimeter survey data from northern Greenland (1994, 1999) with existing southern Greenland data.
- Analyzing elevation changes above and below 2000 meters.
- Interpolating data to estimate net annual ice loss.
Main Results:
- The ice sheet is in balance on average above 2000 meters, with localized thickening and thinning.
- Significant thinning, exceeding 1 meter per year, occurs at lower elevations near the coast.
- An estimated net loss of approximately 51 cubic kilometers of ice per year was determined.
Conclusions:
- The Greenland Ice Sheet is losing mass, primarily at lower elevations.
- This ice loss contributes significantly to global sea level rise, accounting for about 7% of the observed increase.
- Continued monitoring is essential to track ice sheet response to climate change.
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