摘要
选取陕西省分布比较均匀的78个站点,1961-2004年日降水资料,通过对强降水数量进行界定,得到强降水日数,采用4次多项式、最大商谱分析、Mann-Kendall方法进行分析。结果表明:陕西强降水日数变率大,易发生旱涝;20世纪90年代末期以后陕西省强降水日数有增加趋势;在信度α=0.1的水平下,80年代末期到90年代初期,强降水日数发生了由偏多向偏少的突变;强降水日数自北向南依次增加,有2个大值中心,一个在宜君附近,另一个在镇巴附近;关中年一日最大降水量有增多的趋势,每10年增加1.5 mm,强降水的强度在增大。
In this paper,statistical methods,such as the quartic polynomial,maximum entropy spectral analysis and Mann-Kendall test,are used to analyze the daily precipitation data observed by 78 selected meteorological stations distributed evenly in Shaanxi Province during the period from 1961 to 2004,and the heavy precipitation days are acquired by defining heavy precipitation.The results show that the variability of heavy precipitation days was high,and drought and flood occurred easily in Shaanxi Province.The heavy precipitation days was increased after the end-1990s.Under the reliability level of α=0.1,a sharp decrease of heavy precipitation days occurred during the period from the end-1980s to the early-1990s.Heavy precipitation days were increased from the north to the south,and there were two centers with more heavy precipitation days: one was near Yijun,and the other was near Zhenba.The daily maximum precipitation in the Guangzhong region was in an increase trend in recent 40 years,and it was increased by 1.5 mm every ten years.The intensity of heavy precipitation was also increased.
出处
《干旱区研究》
CSCD
北大核心
2011年第5期866-870,共5页
Arid Zone Research
基金
国家自然科学基金(40675021)
陕西省科学技术研究发展计划项目(2005K01-G24)
关键词
强降水
降水日数
气候变化
陕西
heavy precipitation
precipitation days
climate change
Shaanxi Province