近48年云南6种灾害性天气事件频数的时空变化

利用1961～2008年云南省123站6种灾害性天气事件频数资料,对全省灾害性天气频数的空间分布、演变特征和周期进行分析.结果表明:滇中以西地区暴雨频数增加较明显;大风、雷暴频数全省显著减少;冰雹频数全省小幅减少;雾频数中部地区增加,西南部明显减少;霜频数大部分地区减少.云南暴雨频数有微幅增加的演变趋势;雷暴、大风和冰雹频数呈减少趋势;雾和霜频数在1990年代前少变,1990年代初至今趋于减少.暴雨、大风、冰雹和雷暴频数具有15a左右的周期.

The temporal and spatial distribution of 6 disaster weather events in recent 48 years of Yunnan

The temporal,spatial and cyclic distribution analysis of extreme weather frequency changes in Yunnan province have been analyzed by using the 123 points data in 1961—2008.The results of temporal distribution show that the rainstorm days increased significantly at the Midwest Yunnan;the gale and thunder days reduced obviously all over the province;the hail days reduced faintly all over the province; the fog days increased at central section and reduced at peripheral regions; and the frost days reduced at most province.The results of spatial change features show that the rainstorm events continued to increase slightly;the storm,gale and hail events reduced over time,and tended to extend steadily to the 21st century;the fog and frost events were steady in the 1990s and reduced rapidly afterwards.The results of cycle analysis show that the rainstorm,gale,hail and storm events frequency had a low-frequency cycle over 15 years at the same time.