An objective identifi cation technique for regional extreme events (OITREE) and the daily composite-drought index (CI) at 101 stations in Southwest China (including Sichuan, Yunnan, Guizhou, and Chongqing) are u...An objective identifi cation technique for regional extreme events (OITREE) and the daily composite-drought index (CI) at 101 stations in Southwest China (including Sichuan, Yunnan, Guizhou, and Chongqing) are used to detect regional meteorological drought events between 1960 and 2010. Values of the parameters of the OITREE method are determined. A total of 87 drought events are identifi ed, including 9 extreme events. The 2009-2010 drought is the most serious in Southwest China during the past 50 years. The regional meteorological drought events during 1960-2010 generally last for 10-80 days, with the longest being 231 days. Droughts are more common from November to next April, and less common in the remaining months. Droughts occur more often and with greater intensity in Yunnan and southern Sichuan than in other parts of Southwest China. Strong (extreme and severe) regional meteorological drought events can be divided into fi ve types. The southern type has occurred most frequently, and Yunnan is the area most frequently stricken by extreme and severe drought events. The regional meteorological drought events in Southwest China have increased in both frequency and intensity over the study period, and the main reason appears to be a signifi cant decrease in precipitation over this region, but a simultaneous increase in temperature also contributes.展开更多
基金Supported by the National Natural Science Foundation of China(41175075)Climate Change Special Fund of the China Meteorological Administration(CCSF201333)
文摘An objective identifi cation technique for regional extreme events (OITREE) and the daily composite-drought index (CI) at 101 stations in Southwest China (including Sichuan, Yunnan, Guizhou, and Chongqing) are used to detect regional meteorological drought events between 1960 and 2010. Values of the parameters of the OITREE method are determined. A total of 87 drought events are identifi ed, including 9 extreme events. The 2009-2010 drought is the most serious in Southwest China during the past 50 years. The regional meteorological drought events during 1960-2010 generally last for 10-80 days, with the longest being 231 days. Droughts are more common from November to next April, and less common in the remaining months. Droughts occur more often and with greater intensity in Yunnan and southern Sichuan than in other parts of Southwest China. Strong (extreme and severe) regional meteorological drought events can be divided into fi ve types. The southern type has occurred most frequently, and Yunnan is the area most frequently stricken by extreme and severe drought events. The regional meteorological drought events in Southwest China have increased in both frequency and intensity over the study period, and the main reason appears to be a signifi cant decrease in precipitation over this region, but a simultaneous increase in temperature also contributes.