Analysis Of The Variation Characteristics Of Surface Solar Radiation And Its Influencing Factors In Typical Regions Of China In Recent Decades

Surface solar radiation is an important component of the global energy balance.It is the main energy source for the atmospheric cycle and water cycle and has an important impact on global climate change.The trend of total radiation change and the influencing factors are often very different in various regions.In this paper,we use the surface total solar radiation data from68 stations across China from 1961 to 2016,based on strict quality control and homogenization,to further study the long-term variation trend of total radiation in Chinese regions,and select three typical regions,namely,the Tibetan Plateau,North China,and Yangtze River Delta,and combine cloudiness and aerosol optical thickness observation data,by comparing the total radiation under the clear sky and all-day conditions.The main conclusions are as follows.(1)From 1961 to 2016,the total radiation in the Chinese region declined significantly with a trend of-3.36 W m^-2 decade^-1.Among them,there is a significant decreasing trend of total radiation on both annual and seasonal scales in 1961-1989,and this decreasing trend is weakened in 1990-2007 and changed to a significant increasing trend(6.52 W m^-2 decade^-1)in2008-2016,and there is a significant increase of total radiation in all seasons except autumn in this period on seasonal scales.(2)The total radiation in the Tibetan Plateau,North China,and Yangtze River Delta regions all showed a decreasing trend from 1961 to 2016,with the strongest decreasing trend in the Tibetan Plateau(-10.7 W m^-2 decade^-1).In the decreasing phase of the national total radiation from 1961 to 1989,the total radiation of all three regions showed a significant decreasing trend,but in the increasing phase of the total radiation from 2008 to 2016,only the total radiation of all stations in North China showed an increasing trend,the total radiation of Yushu,Changdu and Golmud stations in the eastern region of the Tibetan Plateau increased,the total radiation of Lhasa,Geer and Nagqu stations in the western region decreased,and the total radiation of the Yangtze River Delta The total radiation of Hefei and Nanjing stations in the Yangtze River Delta region increased while that of Shanghai and Hangzhou stations decreased.(3)From 2008 to 2016,the decrease in total radiation at Lhasa,Geer,and Nagqu stations in the western region of the Tibetan Plateau is mainly caused by the increase in total cloudiness and low cloudiness,while the decrease in aerosol and low cloudiness in the eastern region is an important reason for the increase of total radiation at Yushu,Changdu,and Golmud stations.The changes in total radiation in North China are more significantly influenced by aerosols.The changes in total radiation in Hefei and Nanjing stations are more influenced by aerosols,while Shanghai and Hangzhou stations are more influenced by clouds during this period in the Yangtze River Delta region.