Abstract: In order to reveal the essential feature of radiation in extreme arid region of Northwest China, the characteristics of global radiation, direct radiation and diffuse radiation were analyzed by using solar irradiance observation data and meteorological data from January, 2007 to December, 2011. The results show that the annual total of global radiation, diffuse radiation and direct radiation were 6619.0, 3507.8, 2203.5 MJ·m^-2, respectively. The daily peak of global radiation is 2.4 times of diffuse radiation and 1.5 times of direct radiation in the clear day. In the sand storm day, the value of diffuse radiation increases to be consistent with the global radiation, and direct radiation attenuation is obvious. Diffuse radiation increases with the total cloud amount rise when the solar zenith angle is higher than 20°, and it increases significantly in autumn and winter.

Key words: Taklimakan Desert, global radiation, diffuse radiation, direct radiation