Abstract: Based on cloud fraction and cloud optical thickness data which were retrieved from the satellite data, and cloud decrement ratio which was calculated from the ground observation solar radiation, the various statistical regression and estimate model were established in order to estimate the cloudy ground solar radiation in Fujian. The results showed that the power function was the best function format for cloudy ground solar radiation estimate model in Fujian based on the cloud fraction and cloud optical thickness data(P<0.01), and the solar radiation estimate model had definitude physical reason and rationality. The precision of cloudy ground solar radiation estimate model was validated based on radiation data of 2012 from 66 cloudy observation station. The correlation coefficient was 0.975 between the hour-long solar radiation from estimate model and the hour-long solar radiation from ground observation,the mean relative error was 19%. The mean relative error was 11% for the cloudy ground, when the hour-long solar radiation more than 1MJ·m-2·h-1.The method might estimate cloudy ground solar radiation energy by using fully satellite remote sensing data, and it was abandoned that obvious shortage in the model precision or the model stability of spatial application, when the early solar radiation estimate model was established by using of cloud data of common observation station.The solar radiation estimate model had obvious advantage in Fujian,where was sparse ground observation station and obvious local atmosphere environment characteristic.

Key words: Remote sensing, Solar radiation, Cloudy ground, Cloud optical thickness, Cloud fraction