Polar Airborne Observations Fill Gap in Satellite Data



In October 2009, NASA's Ice, Cloud, and land Elevation Satellite (ICESat) stopped collecting science data. However, noting the progressive degradation of ICESat's Geoscience Laser Altimeter System (GLAS), NASA had begun the previous year to plan a series of instrumented aircraft missions to fill the impending gap in satellite observations due to the loss of GLAS. Called Operation IceBridge, the project has been collecting data since March 2009 and will continue until the scheduled launch of ICESat's replacement, ICESat-2, in about 2015.

The primary goal of IceBridge is to use airborne laser altimetry to monitor rapidly changing areas of ice sheets, glaciers, and sea ice; a secondary goal is to acquire ice-penetrating-radar data to map the bedrock topography beneath the ice sheets. Data collected by IceBridge will yield a three-dimensional view of ice sheets and sea ice as they change. IceBridge will improve modeling efforts and knowledge of the contribution of the Greenland and Antarctic ice sheets to sea level rise. The project will also contribute to scientific understanding of changes in the extent and thickness of the sea ice cover as the planet warms. IceBridge flights maintain altimetry time series over outlet glaciers started by NASA in the early 1990s, expand airborne altimeter coverage to new areas, and add grids of ice-penetrating-radar data to better resolve bedrock topography.