Abstract:

Based on the daily precipitation data of 25 conventional weather stations from 1961 to 2013 and 220 automatic weather stations from 2007 to 2013 in Ningxia, the temporal and spatial distribution characteristics of rainstorms in Ningxia were analyzed. The results showed that the rainstorms in Ningxia had been more in the southern part and less in the northern part as a whole, and concentrated in the south of Zhongwei and east of the Helan Mountain. In the past 53 years, there were three concentration periods of rainstorm  including 1961-1979, 1995-2002 and 2006-2013, especially the rainstorms increased sharply after 2000, which mainly appeared in southern mountains of Ningxia and Yinchuan plain. The daily and monthly changes of rainstorm in Ningxia were obvious. The rainstorms concentrated from July to September, and the short-time rainstorms mainly occurred from 16:00 to 02:00, which was more consistent with the daily variation of temperature. The rainstorms in Ningxia had obvious 16 a and 20 a interdecadal, 2-3 a interannual period oscillation and 10 d low frequency oscillation characteristics analyzed by using Mexico-hat wavelet.

Key words: rainstorm, climatic characteristics, high resolution analysis, temporal and spatial distribution

摘要：

利用1961～2013年宁夏25个常规观测站资料和2007～2013年220个区域自动站暴雨观测资料，对宁夏暴雨的气候特征进行分析，发现宁夏暴雨呈“南多北少”的整体分布特征，暴雨易发区为中卫市以南和贺兰山东麓。近53 a来，宁夏暴雨有3个集中期，尤其是21世纪后暴雨剧增，其中宁夏南部山区和银川平原暴雨频数增加明显。宁夏暴雨存在明显的月、日变化特征，暴雨主要发生在7月上旬到9月上旬，短时暴雨主要集中在午后到夜间（即下午16时至次日02时），这一特征与气温（热量）及对流发展的日变化比较一致。宁夏暴雨发生频数存在明显的准16 a、20 a年代际、2～3 a年际变化特征和准10 d的低频振荡特征。

关键词: 暴雨, 气候特征, 精细化, 时空分布