Intercomparison of two trapezoid-based soil moisture downscaling methods using three scaling factors  

作　　者：Jing Tian Xiangzheng Deng Hongbo Su 

机构地区：[1]Key Laboratory of Water Cycle and Related Land Surface Processes,Institute of Geographical Sciences and Natural Resources Research(IGSNRR),Chinese Academy of Sciences(CAS),Beijing,People’s Republic of China [2]Center for Chinese Agricultural Policy,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing,People’s Republic of China [3]Department of Civil,Environmental and Geomatics Engineering,Florida Atlantic University,Boca Raton,FL,USA

出　　处：《International Journal of Digital Earth》2019年第4期485-499,共15页国际数字地球学报（英文）

基　　金：the National Natural Science Foundation of China(41671354);the National Key Research and Development Plan(2016YFA0602501).

摘　　要：This paper compared two soil moisture downscaling methods using three scaling factors.Level 3 soil moisture product of advanced microwave scanning radiometer for EOS(AMSR-E)is downscaled from 25 to 1 km.The downscaled results are compared with the soil moisture observations from polarimetric scanning radiometer(PSR)microwave radiometer and field sampling.The results show that(1)the scaling factor of normalized soil thermal inertia(NSTIs)and vegetation temperature condition index(VTCI)are better than soil evaporative efficiency in reflecting soil moisture;(2)for method 1,NSTIS is the best in the downscaling of soil moisture.For method 2,VTCI is the best;(3)no significant differences of the correlation coefficients(R2)and the biases were found between the two methods for the same scaling factors.However,method 2 shows a better potential than method 1 in the time-series applications of the downscaling of soil moisture;(4)compared with the relationship between the area-averaged soil moisture of AMSR-E and that of PSR,R2 of the 6 sets of the downscaled soil moisture almost do not decrease,which suggests the validity of the downscaling of soil moisture with the two downscaling methods using the three scaling factors.

关 键 词：Soil moisture DOWNSCALING trapezoid-based method scaling factor 

分 类 号：S15[农业科学—土壤学]