关键词: 内蒙古, 降水, 极端事件, Inner Mongolia, precipitation, extreme events

Abstract: Threshold values of extreme precipitation events were determined individually according to the 90th and 95th percentile values of annual daily precipitation series at the 116 meteorological stations of Inner Mongolia during the period 1961-2008. The frequencies, distributive and change characters of extreme precipitation events were examined in recent 48 years. Changes in the frequency and rainfall of extreme precipitation events after the temperature abrupt change in about 1987 were also analyzed. The results show that 1) the threshold values of extreme precipitation events were generally small, within 2.1 and 23.8 mm, the extreme precipitation events occurred 2.4 to 20.9 days in a year, and there were distinctive spatial differences in the distributive character and change of the threshold values, frequencies, and rainfall of extreme precipitation events. 2) Extreme precipitation events in Inner Mongolia whether for summer or for the whole year both showed no obvious trend in recent 48 years. 3) The rainfall of extreme precipitation events decreased in the middle and southeast of Inner Mongolia, but increased in the northeast and west, after the temperature abrupt increase in 1987.