CGRG Bibliography of Canadian Geomorphology
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Author : Arendt, A.; Luthcke, S; Larsen, C.; Abdalati, W.; Lingle, C.; Echelmeyer, K.; and Krabill. W.
Date : 2007.
Title : Combining GRACE and airborne laser sltimetry measurements to calculate ice mass changes in Alaska and northwestern Canada.
Publication : CMOS, CGU, AMS Congress 2007. "Air, Ocean, Earth and Ice on the Rock". May 28 - June 1, 2007. St. John's Congress Centre, Newfoundland and Labrador, Canada.
Issue :
Page(s) : H06-4C4.2.
Abstract
Although smaller in total volume than the ice sheets, glaciers of Alaska and northwestern Canada have high rates of mass turnover and are making a large contribution to rising sea level. Aircraft altimetry measurements have broadened our understanding of the mass variations of these glaciers, but errors in regional estimates remain large. Identifying a set of glaciers to represent a region is a challenge, in part because tidewater glaciers exhibit dynamic variations that are not necessarily synchronous with adjacent glaciers. Time-variable gravity measurements from the NASA/DLR Gravity Recovery and Climate Experiment (GRACE) satellites are providing information about changes in the distribution of mass within and at the surface of the Earth. After correcting for other sources of mass change such as glacial isostatic adjustments (GIA), GRACE yields direct measurements of glacier mass balance, circumventing errors in converting elevation changes to mass equivalents. Here we describe our ongoing efforts to measure mass changes of Alaska glaciers between 2003-2006 using GRACE data. We are employing a unique data processing method that uses inter-satellite range-rate measurements to obtain local mass concentration (mascon) solutions. The high spatial resolution afforded by this approach will improve our ability to isolate glacier mass changes from those occurring outside the region of interest. At the same time, the high temporal resolution will allow us to isolate specific mass change events for comparison with climate data. Our solutions will include explicit corrections for the large rates of GIA that are occurring in the Glacier Bay region in response to recent tidewater disintegration. Elevation changes between NASA's 2005 airborne topographic mapping campaign and the February 2000 Shuttle Radar Topography Mission for glaciers of the Yakutat and Glacier Bay regions will be presented. These illustrate one of several datasets that will be used for validation and comparison with GRACE solutions.
Bibliography of Canadian Geomorphology