干旱区生态环境知识资源中心

Spectral albedo and nadir reflectance of desert surfaces were measured with spectrometer for spectral region from 0.35 to 2.5 mu m in western and central China in spring of 2001 and autumn of 2003. Desert surfaces were mainly gobi and/or sand dune around Qira in southern Taklimakan Desert, Aksu in northern Taklimakan Desert, Ejina in Badain Jaran Desert, and in Tengger Desert. The measured spectral albedos are low (0.05-0.11) at ultraviolet wavelengths but it rapidly increases to 0.2-0.3 at the wavelength about lambda = 0.6 mu m at any site. The wavelength at which the albedo reaches to the maximum is around lambda = 1.8-2.2 mu m, where the albedos range from 0.37 to 0.49 among measured sites. Nadir reflectance also basically shows a similar spectral distribution with that of the albedo, while the values are lower than albedos at any wavelength. Standard deviations of albedo and reflectance calculated from measurements for different surfaces at each site indicate that gobi surfaces around Aksu and Ejina have large variability compared with other surfaces. These datasets would be useful for the studies of climate simulation, remote sensing, radiative forcing, and so on.