接地线是内陆固定冰盖和漂浮冰架的分界线,其位置的准确界定直接影响到南极冰盖物质平衡的计算.随着技术的发展,接地线的提取手段已经逐步从小范围的实地无线电回波测厚和GPS探测,发展到大范围的遥感观测.遥感观测主要包括4种技术手段,即流体静力学平衡、坡度分析、重复轨道分析以及差分干涉测量.以遥感观测为基础,国际上已发布5种全南极接地线产品,包括MOA、ASAID、ICESat、MEaSUREs以及Synthesized接地线产品.随着卫星数据源的丰富,改进接地线提取方法并高精度提取接地线,扩大接地线研究的时间尺度并对全南极进行长时序的接地线动态变化监测,结合冰架底部消融、冰底地形和海洋温度等参数,深入分析其变化原因和机制以及接地线变化与气候变化相互关系的建模等,将会成为南极接地线研究的新热点.%Grounding line is the boundary between inland grounded ice sheet and floating ice shelf. The precise extraction of its location has a significant impact on the Antarctic ice sheet mass balance. Grounding line extraction method has been developed from in situ RES and GPS of small-scale to remote sensing measure-ments of large-scale. Four main techniques of remote sensing measurements, including hydrostatic equilib-rium, slope analysis, repeated track analysis and differential SAR interferometry, lay the foundation of five released grounding line products of the whole Antarctica, named MOA, ASAID, ICESat, MEaSUREs and Synthesized grounding line product. With the development of remote sensing technology, multi-source re-mote sensing data will be used for grounding line extraction with high-precision, and its dynamic changes monitoring with longer temporal scale in whole Antarctica. Moreover, the change mechanism of the grounding line position coupled with bottom melt of ice shelf, bed topography and ocean temperature, and building models of its relationship with climate change will be future research hotpots.
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