Spatio-temporal Variation of Freeze-thaw Cycles in the Qinghai-Xizang Plateau from 1981 to 2020 Based on Microwave Remote Sensing  

作　　者：ZHAO Shangmin ZHANG Shifang YU Bohan 

机构地区：[1]College of Geological and Surveying Engineering,Taiyuan University of Technology,Taiyuan 030024,China [2]School of Traffic Engineering,Shanxi Vocational University of Engineering Science and Technology,Jinzhong 030619,China

出　　处：《Journal of Geodesy and Geoinformation Science》2025年第1期1-11,共11页测绘学报(英文版)

基　　金：National Natural Science foundation of China(No.42271432);Foundation of Shanxi Vocational University of Engineering Science and Technology(No.KJ 202426).

摘　　要：Strong sensitivity of satellite microwave remote sensing to the change of surface dielectric properties,as well as the insensitivity to air pollution and solar illumination effects,makes it very suitable for monitoring freeze-thaw conditions.The freeze-thaw cycle changes in the Qinghai-Xizang Plateau have an important impact on the ecological environment and infrastructure.Based on the Scanning Multi-channel Microwave Radiometer(SMMR)and other sensors of microwave satellite,the freeze-thaw cycle data of permafrost in the Qinghai-Xizang Plateau in the past 40 years from 1981 to 2020 was obtained.The changes of soil freeze-thaw conditions in different seasons of 2020 and in the same season of 1990,2000,2010 and 2020 were compared,and the annual variation trend of soil freeze-thaw area in the four years was analyzed.Further,the linear regression analysis was carried out on the duration of soil freezing/thawing/transition and the interannual variation trend under different area conditions from 1981 to 2020.The results show that the freeze-thaw changes in different years are similar.In winter,it is mainly frozen for about 110 days.Spring and autumn are transitional periods,lasting for 170 days.In summer,it is mainly thawed for about 80 days.From 1981 to 2020,the freezing period and the average freezing area of the Qinghai-Xizang Plateau decreased at a rate of 0.22 days and 1986 km^(2) per year,respectively,while the thawing period and the average thawing area increased at a rate of 0.07 days and 3187 km^(2) per year,respectively.The research results provide important theoretical support for the ecological environment and permafrost protection of the Qinghai-Xizang Plateau.

关 键 词：freeze-thaw cycle PERMAFROST microwave remote sensing spatio-temporal variation linear regression analysis Qinghai-Xizang Plateau 

分 类 号：P642.14[天文地球—工程地质学]