Permafrost environment monitoring on the Qinghai-Tibet Plateau using time series ASAR images  

作　　者：Zhen Li Panpan Tang Jianmin Zhou Bangsen Tian Quan Chen Sitao Fu 

机构地区：[1]Key Laboratory of Digital Earth,Institute of Remote Sensing and Digital Earth,Chinese Academy of Sciences,Beijing,China [2]Institute of Remote Sensing and Digital Earth,University of the Chinese Academy of Sciences,Beijing,China

出　　处：《International Journal of Digital Earth》2015年第10期840-860,共21页国际数字地球学报（英文）

基　　金：This study was supported by the CEODE Director Fund Project[grant number Y2ZZ05101B];Chinese Ministry of Science and Technology[grant numbers 2010CB951403 and 2011AA120403];and the National Natural Science Foundation of China[grant numbers 41001042 and 41201447].

摘　　要：The permafrost in Qinghai-Tibet Plateau(QTP)has long been the focus of many researchers.In this study,we first use the method that integrates synthetic aperture radar(SAR)intensity and phase information to monitor permafrost environment in the Beiluhe Region,using time series advanced SAR images.The backscattering coefficients(σ^(0))and deformation were extracted for the main features,and the influences of meteorological conditions to them were also quantified.The results show that both the change inσ^(0)and surface deformation are closely related to the active layer,and the deformation is also affected by the permafrost table.First,over meadow and sparse vegetation regions,σ^(0)rose about 6.9 and 4 dB from the freezing to thawing period,respectively,which can be mainly attributed to the thaw of the active layer and increased precipitation.Second,seasonal deformation,derived from the freeze-thaw cycle of the active layer,was characteristic of frost heave and thaw settlement and exhibited a negative correlation with air temperature.Its magnitude was larger than 1 cm in a seasonal cycle.Last,significant secular settlement was observed,with rates ranging from-16 to 2 mm/a,and it was primarily due to the thaw of the permafrost table caused by climate warming.

关 键 词：Qinghai-Tibet Plateau ASAR permafrost environment backscattering coefficients deformation climate warming 

分 类 号：P64[天文地球—地质矿产勘探]