新疆冰雹历时的气候特征

Climatic Characteristics of Hail Duration in Xinjiang

利用1961-2011年新疆54个地面气象观测站全天记录的天气现象数据,通过软件识别和分离出冰雹出现的起止时间,计算每个冰雹事件的历时,并对历时气候特征进行分析。结果标明,新疆冰雹年历时的高值区位于天山西段和天山南脉,年历时前5位的观测站依次是昭苏(179min)、巴音布鲁克(103min)、乌恰(59min)、阿合奇(31min)和温泉(22min);6月冰雹历时最长,5月次之,有63%的冰雹历时在6min以内,98.5%的冰雹历时不超过30min;1961-2011年新疆冰雹历时的年际变化呈显著的线性减少趋势,每10年减少2min。5-8月地面蒸发量和归一化对流有效位能的逐年减少是导致新疆冰雹年历时逐年减少的主要原因。

Based on the records of weather phenomenon recorded all day by 54 ground meteorological observation stations in Xin⁃jiang from 1961 to 2011.The start and end time of hail identified and separated from the weather phenomenon records by using soft⁃ware,and then the duration of each hail event calculated according to the start and end time.The analysis of the climatic characteris⁃tics of hail duration shows that the high value area of the annual duration of hail in Xinjiang is located in the west section of Tianshan Mountain and the south range of Tianshan Mountain.The top five stations of annual duration are Zhaosu(179 min),Bayinbuluk(103 min),Wuqia(59 min),Aheqi(31 min)and Wenquan(22 min).The hail duration in June is the longest,followed by May.63%of the hail duration is within 6 min and 98.5%of the hail duration is no more than 30 min.The inter-annual variation of hail duration in Xinjiang from 1961 to 2011 shows a significant linear decreasing trend,decreasing by 2 minutes every 10 years.The annual decrease of ground evaporation and normalized convective available potential energy from May to August leads to the change of the annual dura⁃tion of hail in Xinjiang.