中国年代际暴雨时空变化格局

Spatio-temporal Patterns of China Decadal Storm Rainfall

采用1951～2010年中国659个气象站点的日值降水数据，以中国气象局颁布的降水强度等级划分标准为依据，分别计算1951～1960、1961～1970、1971～1980、1981～1990、1991～2000、2001～2010年的年代际暴雨雨量、雨日和雨强，并统计了其相应的站点数目变化。结果表明，在时间上，中国年代际暴雨雨量和雨日显著增加，暴雨雨强也呈现增加趋势；在空间上，中国年代际暴雨雨量和雨日呈现出从东南沿海地区向华中和西南及环渤海地区逐渐扩张的梯度增加趋势，年代际暴雨雨强远不如暴雨雨量和暴雨雨日梯变明显。中国暴雨1951～2010年年代际时空变化格局很可能是在全球变暖大背景下中国地势与城市化共同作用的结果。

Extreme precipitation events in recent years have become an important factor affecting the global and regional environmental risk, which has become the focus of attention of academia. It is the hot topic wheth- er China＇s extreme precipitation changed significantly or not on the overall. Previous studies have not ad- dressed the China＇ s decadal storm rainfall, so there is no global understanding to this problem. To address this problem, we conducted the in-depth study. In this research, daily precipitation datasets of 659 meteorological stations come from China Meteorological Administration in 1951-2010. According to the precipitation intensi- ty grading standards promulgated by the China Meteorological Administration, we calculated the decadal storm rainfall amounts, storm rainfall days and storm rainfall intensity in 1951-1960, 1961-1970, 1971-1980, 1981-1990, 1991-2000, 2001-2010. The results showed that： in the time dimension, China＇ s decadal storm rainfall amount and storm rainfall days increased significantly. At the same time, the storm rainfall intensity al- so showed a lightly increasing trend. In the space dimension, China＇ s decadal storm rainfall amounts and storm rainfall days showed an gradient increase trend, which showed gradual expansion from southeast coastal areas to the Central and Southwest China. The regions are about located in the east of the line from Mohe County in Heilongjiang Province to Tengchong County in Ytmnan Province. However, China＇ s decadal storm rainfall intensity is far less apparent than storm rainfall amount and storm rainfall days. The meteorological sta- tions number of China＇ s decadal storm rainfall amounts also changed significantly. The number of meteorolog- ical station with decadal storm rainfall amount less than 5 000 mm was 647 in 1951-1960, and reduced to 333 in 2001-2010. At the same time, the number of meteorological station with decadal storm rainfall amount more than 8 000 mm was 2 in 1951-1960, and increased to 286 in 2001-2010. The number of meteorological station with decadal storm rainfall days less than 30 d was 547 in 1951-1960, and reduced to 233 in 2001-2010. At the same time, the number of meteorological station with decadal storm rainfall days more than 120 d was 0 in 1951-1960, and increased to 265 in 2001-2010. The number of meteorological station with decadal storm rain- fall intensity less than 75 mm/d was 476in 1951-1960, and reduced to 466 in 2001-2010. At the same time, number the meteorological station with decadal storm rainfall intensity 75-100 mm/d was 174 in 1951-1960, and increased to 191 in 2001-2010. Spatio-temporal patterns of China＇s decadal storm rainfall in 1951-2010 may be the result of global warming in the large-scale background topography and urbanization joint affect throughout China. To what extent natural factors and human factors played a great role to the storm rainfall, it is yet to be further in-depth study.