利用时序PS-InSAR监测青藏高原冻土区地表形变

多年冻土及其活动层的变化对研究全球气候变化和生物多样性具有重要意义。传统的冻土测量方法通常只针对特定地点，空间覆盖范围有限，尤其是青藏高原冻土。本文采用C波段Sentinel-1A IW模式数据并结合一种顾及永久散射体的小基线SAR干涉（SBAS）技术，对青藏高原沱沱河地区地面形变和冻融过程进行了研究。探测到的地面位移速率（主要范围为-20~20 mm/a）和位移时间序列反映了多年冻土及活动层的演化。试验结果与水准测量数据具有较好的一致性，且该方法优于一般多时相InSAR方法。此外，分析了SAR成像几何与地表位移之间的关系，解释了在多年冻土区特别是对于山坡的运动趋势。试验结果展示了InSAR的监测能力，并提高了对多年冻土区地表形变的认识。

Permafrost deformation in Qinghai-Tibet Plateau time-series PS-InSAR

The permafrost and the active layer variations are closely related to global climate change and biodiversity. However,the traditional measurements of the permafrost are usually restricted within regionally specific sites and the spatial coverage is limited. In this paper,the C-band Sentinel-1A IW model data with small baseline SAR interferometry( SBAS) technique considering permanent scatterers is used to study the surface deformation and frost-thawing in the Tuotuohe permafrost region of Qinghai-Tibet Plateau. The estimated surface displacement rate( mainly ranging from -20 to 20 mm/a) and displacement time series reflected the evolution of permafrost and active layer. In addition,the results are consistent with the leveling data,and furthermore this method is better than the general multi-temporal InSAR method. In addition,the relationship between SAR imaging geometry and surface displacement is analyzed and the motion trend is better explained,especially for slopes. The results show the monitoring ability of InSAR,which improves our understanding of the surface deformation in permafrost area.