利用线性回归、M-K等方法,对永城站1960年12月～2010年11月的月、李、年降水量资料进行综合分析.结论表明,近50年永城市年、季降水量线性变化趋势均不显著,春、夏、秋季及年降水量在减少,冬季降水量略有增加.月降水量4和9月分别以-6.856和-12.549 mm/10a呈显著减少趋势,其他月份无论是增多或减少均不显著.年降水量没有明显的突变点,月、季降水量的突变时间冬季在1985年、春季在1993年、夏季在1966和1999年、秋季在1989年；4、8、9、12月分别在1975、1964、1986、2000年.春夏秋季降水量均在减少,致使年降水量减少,秋季降水量减少的速率较大,是近几年连续出现秋季异常气象干旱现象的原因.%By using linear regression, Mann-Kendall and other methods, month, seasonal, annual precipitation in Yongcheng during Dec. 1960-Nov. 2010 were analyzed. The results indicated that the trend of annual and seasonal precipitation in Yongcheng City in recent 50 years is not significant, in spring, summer and autumn, the precipitation shows an decreasing trend, and increasing in winter. Precipitation in Apr. and Sep. are significantly decreasing at -6.856 and -12.549 mm/'10a, in other month, the trend is not significant. The mutation of annual precipitation is not obvious and obvious in monthly and seasonal precipitation. In the spring, summer, autumn and winter, the mutation occurred respectively in 1993, 1966 and 1999, 1989, 1985, respectively. The mutation of Apr. , Aug. , Sep. and Dec. occurred respectively in 1975, 1964,1986 and 2000. Trie amount of precipitation of spring, summer and fall were reduced and this led the reduction of the annual precipitation. The reason of the phenomenon that in recent years it continuously appeared abnormal meteorological drought in autumn was that the reduction rate of the amount of precipitation of autumn was larger.
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