H31A-1401
Observational study of surface spectral radiation and corresponding albedo over Gobi, desert, and bare loess surfaces in northwestern China

Wednesday, 16 December 2015
Poster Hall (Moscone South)
Zhiyuan Zheng1,2, Wenjie Dong3, Zhenchao Li4, Wei Zhao3, Shanshan Hu1, Xiaodong Yan1, Jiaqi Zhao5 and Zhigang Wei3, (1)Beijing Normal University, Beijing, China, (2)Beijing Normal University, Zhuhai, Future Earth Research Institute, Zhuhai, China, (3)BNU Beijing Normal University, Beijing, China, (4)Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,, Lanzhou, China, (5)Songyuan Meteorological Bureau, songyuan, China
Abstract:
In this paper, the field experiments on ground surface spectral broadband solar radiation (SR) and corresponding albedo were introduced at three man-made sites at Gobi, desert, and bare loess zones during three different intensive observational periods (IOP) from 2010 to 2013 in Gansu Province, respectively. The continuous and high temporal resolution records of ground surface solar radiation are presented, including global (GR), ultraviolet (UV), visible (VIS), and near-infrared radiation (NIR). The corresponding albedos are analyzed over three typical non-vegetated underlying surfaces in arid and semiarid and semihumid regions of northwestern China. The preliminary investigations were carried out. The results show that the variation trends of UV, VIS, and NIR are coincident with the GR, and the irradiances are gradually decreasing throughout the IOP at each site; the energy ratios of VIS/GR are all approximately 40.2%, and the ratios of NIR/GR are all approximately 54.4% at the Gobi, desert, and bare loess zones; and the averaged albedos of the soil for VIS are 0.231, 0.211, and 0.142 and for the NIR are 0.266, 0.252, and 0.255 over the Gobi, desert, and bare loess land surfaces, respectively. The energy ratios of VIS/GR and NIR/GR are not 50% as prescribed for all of the soil color classes in most of land surface models (LSMs). The observational soil albedo values for NIR are not twice to that of the VIS as predicted in some LSMs for the underlying surface at the three sites. GR albedo is determined by the energy ratios of SR/GR and SR albedos.