商水县近50年冷空气活动概况分析

Analysis on the Cold Air Activity in Shangshui County during the Past 50 Years

对1959～2009年商水县中等强度及以上冷空气活动进行统计分析,结果表明,除夏季的7月份外,其他月份均有不同程度冷空气活动,以秋、春、冬季为高,活动频率分别为40%、32%和24%,而春、夏、秋、冬季伴有≥0.1 mm降水的概率分别为69%、75%、44%、39%;年度冷空气活动次数与活动频率之间有很好的反相关关系。

According to the statistics about the moderate and high intensity cold air activities in Shangshui County from 1959 to 2009,different degrees of cold air occurred in all months except in July,especially in autumn,spring and winter when the frequency of cold air was 40%,32% and 24%,respectively.The probability of cold air accompanied with ≥0.1 mm precipitation was 69%,75%,44% and 39% respectively in spring,summer,autumn and winter.The annual occurrence times of cold air were negatively correlated with its annual frequency.