Summary: | We initially derived elevation changes of Geoscience Laser Altimeter System level-2 altimetry data of Lambert Glacier overlapping footprints during each mission from 2003 to 2008. Then, surface elevation changes during every two adjacent missions were interpolated using inverse distance weighted, natural neighbor, triangulated irregular network with linear method, radial basis functions and ANUDEM in ArcGIS. The best results were obtained by ANUDEM, so these data were clipped to conform to the study area boundary defined by hydrology tools. Finally, elevation changes over 10 periods were mapped. In these maps, we chose the Antarctic digital elevation model as background and used a translucent layer to mask the area outside Lambert Glacier, and then displayed elevation changes using gradient colors. Results indicate that elevation changes of the entire Lambert Glacier are not evident, particularly in the upstream area. There are a few elevation changes in some downstream areas. Elevation of the grounding zone in the southernmost Amery Ice Shelf decreased more than 2 m in 2004-2005, 2006-2007, and during 2008.
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