Research on the Calculating of Surface Net Radiation in China
中国地表净辐射推算方法的研究

Surface net radiation is an important driving force to climate change or even global change,and one of the important parameters for establishing various kinds of ecological models.However,the relatively few surface net radiation stations in China can not meet the needs of scientific research and operation.There is an urgent need to establish or screen out a method suitable for calculating surface net radiation in China.Therefore,by use of 1993-2000 radiation and related meteorology data from 50 net radiation stations in China,net radiations monthly were calculated using 5 methods,independently.By comparing the error of each method,we found that synthesis method including multi-factors constructed in this paper was proved to be a perfect method with mean relative error of 50 stations is 0.348,and <0.20 from April to September,which can be applied in the calculation of net radiation every month.In addition,methods of Chang Jen_Hu formula and Penmann formula with the mean relative error of 50 stations is <0.64,<0.25 from April to September and the number of months <0.20 account for about half of the year can be applied in the calculation of surface net radiation during growth period.Mean relative errors induced using various methods have a temporal and spatial distribution characteristic that the values in northern China are bigger than those of the southern China and summer month(March to October) are bigger than winter month(November to January).