Permafrost Subsidence Monitoring of Qinghai-Tibet Plateau using Sentinel-1 Data

Qinghai-Tibet Plateau (QTP) experienced seasonal freeze-thaw cycles. In this study a modified Stefan piecewise elevation changes model based on air temperature data was integrated to new small baselines subset (NSBAS) chain. A total of 33 scenes of Sentinel-1 data (S-1) with one year time range were collected to build the Multitemporal interferometric synthetic aperture radar (MT-InSAR) analyzing network. The results revealed that estimated seasonal surface subsidence ranged from -60 to 0 mm and the linear subsidence value was about 10 mm/yr. Higher correlation between topography slope and subsidence was acquired compared with sinusoidal seasonal model-based results. Surface displacements variation of different land covers were acquired. The result shows that the seasonal subsidence over alpine meadow was higher than alpine desert areas.