关键词: 中国, 降水量, 降水面积, 变化特征

Abstract: The nonuniformity of precipitation elements (precipitation, precipitation intensity,precipitation frequency,precipitation area) in time and space leads to the frequent occurrence of many natural disasters (storms,floods,continuous rain,landslides,mudslides,et al.),causing great losses to people’s production and life,which have raised great concern. Based on 0.5°×0.5° monthly and daily precipitation grid datasets in China from 1961 to 2015,the characteristics of precipitation and precipitation area in three regions of China were analyzed using linear trend method,Kriging interpolation method and forest slope method.The annual and seasonal average precipitation both presented a decreasing pattern from the southeast coast to the northwest inland,the annual and seasonal average precipitation in over half of China’s region showed an increasing trend.In terms of daily and seasonal variations,light rain and moderate rain mainly were concentrated in the eastern monsoon region and the northwest arid region and the QinghaiTibet alpine region of China,but the area occupied by rainstorm and heavy rainstorm was small.The annual variation of daily precipitation area at different levels in the three regions followed a quadratic function curve,and the inter annual variation of the average precipitation area in the three regions showed a slight decrease.The heavy rain,rainstorm and downpour displayed a slightly increasing trend in the QinghaiTibet alpine region and the arid areas of northwest China.From the seasonal change characteristic perspective,the light rain dominated in all seasons in the three regions.The areas with rainstorm or downpour accounted for a smaller proportion.Precipitation areas of light rain in the three regions in spring and autumn showed a decreasing trend,and rainstorm in spring and summer showed an increasing trend,and moderate rain and heavy rain in winter showed an increasing trend.The precipitation areas at different levels of precipitation all conformed to a negative index distribution in the eastern monsoon region in spring and autumn,in the arid areas of northwest China in all seasons and in the QinghaiTibet alpine region in spring,autumn and winter.The variation characteristics of precipitation area in China provides a good basis for formulating climate change strategies.It is also of great significance for the comprehensive management of water resources and flood control and disaster mitigation in the basin.

Key words: China, precipitation, precipitation area, changing characteristics