新疆阿克苏地区50a来强冰雹天气的气候特征

Climate Characteristics of Severe Hail Events during 50 Years in Aksu,Xinjiang,China

分析了1961—2010年50 a来新疆阿克苏地区强冰雹天气的时间序列变化和空间分布特征,从天气预报的角度对强冰雹天气的影响系统和环流形势进行了分型研究。结果表明,阿克苏地区强冰雹天气呈增多的趋势,局地性强冰雹明显多于系统性强冰雹。强冰雹每年4—10月出现,5—7月为高发时段。将强冰雹天气的影响系统和环流形势分为4类,其中巴尔喀什湖和中亚地区的低值系统是最重要的影响系统。并得出强冰雹的地域分布特征,初步建立了强冰雹天气的探空特征物理量参数的预警指标。

Temporal variation and spatial distribution characteristics of severe hail events in Aksu,Xinjiang,China during 1961—2010 were investigated,and climate systems and circulation situations resulting in severe hail events were also analyzed from aspect of weather forecast.The results show that severe hail events in Aksu appear an increasing trend,and local severe hail events are obviously more than systemic severe hail events.Severe hail events mainly occur from April to October,and the high-frequency period is from May to July.Main climatic systems and circulation situations resulting in severe hail events can be classified into 4 types,and low pressure systems of the Balkhash Lake and Middle Asia are the most important systems.In this paper,the geographical distribution characteristics of severe hail events were concluded,and a pre-warning index system of sounding physical parameters for severe hail events were also given.