雷达高度计探测东南极地区冰面变化

利用美国SeaSat和GeoSat星载高度计,采用再跟踪算法完成雷达高度计数据处理,对大气影响、固体地球潮汛、坡度和水汽进行误差纠正,提取了南极东南部研究区两个年代的从海岸到72°S的数条截面多条冰面剖面.结果表明:Lambert冰川/Amery冰架在1978-1986年间,Lambert冰川以西冰面平均高度上升0.92m,Lambert冰川以东冰面平均高度上升0.47m.

Ice Surface Variation in East Antarctica Surveyed by Satellite Altimetry

It is very importance to monitoring the change of ice sheet surface elevation for studying the mass balance in Antarctica. Satellite altimetry survey provides an advanced measure to automatically detecting the surface change. The direct approach for estimating net mass balance can be based on precise survey of ice-sheet surface elevation using radar or laser altimeters from satellites and/or aircraft. The SeaSat and GeoSat satellite radar altimeters provide the maximum coverage in the Antarctic Ice Sheet up to 72.1°S. SeaSat and GeoSat satellite radar altimeter measurement data were selected to analyze the surface change in East Antarctica. Data were processed using the method of Martin for extracting, then Goddard Earth Model T₂ orbits were used to data reduction, and the serial corrections methods were employed for atmospheric effects, solid Earth tides, slope and water-vapor correction. Several elevation profiles between 1978 and 1986 in the study area were extracted after data processing. Comparing several profiles from coast to 72°S along different longitudes, it is found that on the west side of the Lambert Glacier, the ice-surface elevation has risen 0.92 m on the average, while on its west side the elevation has risen 0.47 m. Repeatedly measuring facilitates the monitoring of change in surface elevation, which improves the study on mass balance and stability of Antarctic Ice Sheet.