利用Sentinel-1A/1B雷达卫星数据监测南极接地线回退状况

南极接地线位置的准确确定对南极物质平衡计算、冰川动力学等具有重要意义。本文阐述了双差干涉测量（DDInSAR）提取接地线的基本原理，并利用欧空局Sentinel-1A/1B雷达卫星数据，基于双差干涉测量技术分别提取了东南极毛德皇后地沿岸冰架与西南极阿蒙森湾西侧Dotson冰架的接地线，将提取结果与已有接地线产品MEa-SUREs进行对比分析。结果表明，利用Sentinel-1A/1B雷达卫星数据，基于DDInSAR方法可对南极接地线进行提取及更新，并可对接地线的回退状况进行持续监测。通过监测，发现在Dotson冰架区域，接地线发生了较大的回退，1996—2018年的22年间，该区域的接地线大约回退2~5 km，其中最大回退距离达7.4 km。

Using Sentinel-1A/1B radar data to monitor the retreat of Antarctic grounding line

The accurate determination of the position of Antarctic grounding line is of great importance to the calculation of Antarctic material balance and the glacial dynamics. The basic principle of the DDInSAR extraction ground line is described, and the ground line of ice shelves along the Queen Maud Land of the east Antarctica and Dotson on the west of the Amundsen Bay of the west Antarctic are extracted using the Sentinel-1A/1B radar data. The extraction results are compared with the existing ground line product MEa-SUREs. The results show that using the Sentinel-1A/1B radar data based on DDInSAR method can extract and update the Antarctic ground line, and continuously monitor the grounding line retreat. Through monitoring, it can be found that in the area of Dotson Ice Shelf, the grounding line has undergone a large retreat, approximately 2~5 km back over the 22 years from 1996 to 2018, with a maximum retreat of 7.4 km.