Influence of air pollution on solar radiation at Ürümqi city in China, using MODIS product

Based on the meteorological datasets, solar radiation fluxes at Ürümqi city for the period of 1960-2009 is estimated and analyzed in this research. Then, Aerosol Optical Depth (AOD), extracted from MOD08_M3 product, is made used to investigate the effect of air pollution on solar radiation. The results show that: 1) for Ürümqi city, solar radiation exhibits an obviously decreased trend during 1960-1992, and begins to rising after 1992; 2) the difference of solar radiation between Ürümqi city and Daxigou (suburb of Ürümqi) is gradually increasing from 1966 to 1998, after 1998 it begins to decreased, dueling to the influence of air pollution at Ürümqi city; 3) aerosol optical depth of Ürümqi city puts up a decreased trend from 2000 to 2009, while solar radiation variation represents an increased trend at the same period, which implicates that aerosol in atmosphere layer has the greatly damping effect on solar radiation.