| Solar radiation is the primary and unique energy of all activities taking place on the earth. It also plays a crucial role in occurrence and development of life on the earth. The changes of solar radiation have significant influence on agriculture, forestry, resources environment, resources ecological, and so on. The observation sites of solar radiation are rare in China, though it is necessary to simulate calculating solar radiation of other area by means of the existing routine meteorological monitoring data. The existed researches of estimating solar radiation mostly focus on using the sunshine and cloud parameters. This paper studies the methods about using temperature data to estimate specialization solar radiation, which can provide basic data for crop simulation, building crop simulation model and provide services for agricultural climate zoning and environmental management. The main results of research are as follows:(1) The Characteristic analysis of meteorological elementAverage annual global solar radiation is in 3,200-3,500 MJ·m-2·a-1 on the southwest of China range from 1971 to 2000. The radiation levels less than other domestic area. With the national trend, the change of global solar radiation overall downward in the past 30 years, Lowest in 80 years, the late 90s increase slightly. Through comparative analysis between the five sites, global solar radiation levels from high to low in turn:Guiyang, Nanchong, Chegndu, Zunyi, Chongqing. The average temperature in the area is rising year by year, and since 1990 the temperature rise faster,30 years average increased 0.43℃.Global solar radiation and temperature of the relevant analysis shows that:monthly daily global solar radiation and mean monthly temperatures, highest monthly temperature, minimum monthly temperatures have reached significant correlation. Among them, the correlation coefficient of monthly daily global solar radiation and mean monthly temperatures is the highest, many sites average to 0.88. According to the correlation analysis of the daily temperature range and global solar radiation, The higher(lower) daily temperature range, the more(less) surface absorption of global solar radiation(2) Equipment Modeling based on the temperatureBy analyzing the relationship between temperature and the solar radiation data in empirical models,4 different month-daily solar radiation models were compared. The results show that model (5-4) with a high coefficient (R2=0.910) and root mean square error (RMSE) 1.484 MJ·m-2·d-1 is much better than others. Therefore model and formula were selected as the estimation formulas applied in the study area.(3) Comparison Study of Spatial Change of TemperatureThe spatial interpolation methods of Ordinary Kriging, Co-Kriging, Regression Kriging are utilized for the comparison study on spatial interpolation of monthly maximum temperature and monthly minimum temperature in the Chongqing. The result s of the there methods display a nearly similar spatial structure. but regression kriging than other two methods more precise in the topography fluctuation larger mountain range. In January, April, July. October are such. Therefore, prediction results from high to low accuracy in order:regression kriging, co-kriging, ordinary kriging.(4) The spatial distribution of solar radiationTaking Chongqing as example, we estimated the total solar radiation of each mouth in 2000 using the solar radiation model selected. The result showed that the astronomy radiation had obvious influence on the total solar radiation's distribution in whole. The total solar radiation shows significant influence by the elevation in the mountain range of southeast and southwest of Chongqing. Fitting results provide reference information for the study area which lack of solar radiation. Meanwhile, the solar radiation model which based on the temperature in this study also put forward a new idea for the estimation of the total solar radiation.
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