青海海南地区近50年极端天气气候事件的变化特征

利用1961—2010年青海省海南地区5个观测站大风、沙尘暴、大雨、雷暴、冰雹等极端天气气候事件的年发生日数资料,采用线性倾向估计、多项式法、Mann-Kendll法、Morlet小波等统计学方法诊断分析其变化特征。结果表明：近50年来,海南地区大风、沙尘暴、冰雹和雷暴呈显著减少趋势,大雨呈微弱增多趋势,其中雷暴、大风、沙尘暴和冰雹分别于2000、2002、2004和2005年前后发生突变;大雨频数总体变化不显著。20世纪90年代初,大风、冰雹和雷暴由多趋少,大雨由少趋多,沙尘暴从20世纪90年代后期由多趋少。

Change Characteristics of Extreme Weather and Climatic Events in Hainan of Qinghai Province in Recent 50 Years

This paper analyzed the change characteristics of extreme weather and climate events, such as gale, sandstorm, heavy rain, thunderstorm and hail over the Hainan using the data of annual occurring days of extreme weather and climate events from 5 meteorological stations in the Hainan during the period of 1961 to 2010 and the statistical methods, such as linear trend, polynomial, Mann-Kendall test and Morlet wavelet analysis. The results showed that the annual days of occurring some extreme weather events, such as gale, sandstorm, thunderstorm and hail over the Hainan in recent 50 years had been obviously decreased, but the heavy rain over the Hainan in recent 50 years had been weakly increased. Of which the abrupt change of occurrence of thunderstorm, gale, sandstorm and hail occurred around 2000, 2002, 2004 and 2005 respectively.Generally,the change of the frequencies of heavy rain is not so obvious.In the early 1990s,the annual days of occurring gale,hail and thunderstorm were decreased,but the heavy rain was increased,in the late 1990s,the annual days of occurring thunderstorm was decreased.