Comparatively observational study of the surface albedo between the permafrost region and the seasonally frozen soil region

Albedo is an important parameter in the study of land surface process.The data of radiation,soil moisture content,snowdcpth,and so on,at the Tanggula metcorological site(TGLMS) and the Bijie site(BJMS) in 2008 were used.The albedoes in the permafrost region and seasonally frozen soil region were analysed. The albedocs of the two sites were bigger in spring and winter but smaller in summer and autumn.The albedo extreme values were caused by snow cover with the maximum extreme value close to 0.9.The albedo at TGLMS was greater than the one at BJMS, and the yearly averaged albedo were 0.38 and 0.31 in these two sites.respectively.The monthly albedo difference(the difference between the daily maxmum value and the daily minimum value in every month) at BJMS was bigger than that at TGLMS in winter, but it was inverse in summer and autumn.In typical clear days,the diurnal variations of albedo took an "U" shape, and it indicated that the albedo was bigger in morning and evening but smaller at noon. The daily average albedo on the typical clear days of spring, summer,autumn and winter were respectively 0. 23.0. 20.0.20 and 0. 25 at TGLMS, and the ones at BJMS were 0. 26,0. 21,0. 22 and 0. 29,respectivcly. Moreover, the relationships between the albedo and solar altitude angle and soil moisture content were discusscd.The albedo exponentially decreased with the increasing solar altitude angl.The albedo negatively correlated to the soil moisture content and was greatly influenced by the precipitation.