Amery冰架附近区域年际表面高程变化分析

Annual Elevation Change Analysis of Amery Ice Shelf and Its Surroundings

使用基于坡度改正的ICESat(冰云和地面高度卫星)激光测高数据重复轨分析法对2003至2009年2月与10月Amery冰架及其附近区域进行了表面高程变化分析.该区域的ICESat轨道重复轨之间的平均距离为100m,平均坡度为0.3%,使用数字高程模型(DEM)进行重复轨间的坡度改正可以消除坡度对重复轨之间高程点投影时的影响.最终得到了2003～2009年2月和10月的总体平均高程变化,以及不同高程区间内的平均高程变化.结果表明海拔较低即更靠近海洋的区域高程变化剧烈,波动范围在±40cm左右甚至超出,而海拔较高即内陆区域的高程变化较缓和,波动范围在±10cm以内.

Elevation change analysis was conducted on the ice,cloud,and land elevation satellite(ICESat) altimetry data collected around the Amery ice shelf(AIS) from 2003 to 2009 with a repeat-track method.The average cross-track separation between the repeat-tracks at AIS was 100 m,and the general slope was 0.3%.An existing digital elevation model(DEM) was used to correct for effects caused by the surface slope across the repeat-track pairs.The average elevation changes were achieved in the entire study area and also within several layers of elevations in the study area.The results show that coastal areas with lower elevations tend to have significant elevation changes,ranging from-40 cm to +40 cm,while interior areas with higher elevations tend to change at a low level in the range of ±10 cm.