Spatial-Temporal Variations of Solar Radiation in Sichuan Province in Recent 44 Years

Based on duration of sunshine month by month at 144 stations and observation data of global radiation month by month at 6 stations of Sichuan Province from 1971 to 2014, global radiation at 144 stations in Sichuan Province were calculated month by month by using climatic simulate method. Based on average distribution of global radiation and the first mode of EOF analysis in Sichuan Province in recent 44 years, 3 climate subareas could be divided in Sichuan Province, and spatial-temporal variations of global radiation in Sichuan Province were studied. The results are as follows: (1) the global radiation in Sichuan Province increased from southeast to northwest with increasement of altitude, and 3 climate subareas which were West-Sichuan Plateau, Panzhihua-Xichang area, Sichuan Basin could be divided in Sichuan Province Based on the first mode of EOF analysis of global radiation. (2) global radiation in West-Sichuan Plateau descended first and then unchanged with time, global radiation in Panzhihua-Xichang area descended first and then rose with time, global radiation in Sichuan Basin had little change and declined slowly. (3) the global radiation in most areas of Sichuan Province were positive departure in 1970 s, the global radiation which were in areas except West-Sichuan Plateau and Ya'an area were negative departure in 1980 s, the global radiation were negative departure in 1990 s, the global radiation which were in area except Panzhihua-Xichang area were negative departure from 2001 to 2014.