An Analysis on Climatic Variation Characteristics of Thunderstorm in Chongqing
With the observational thunderstorm data of 34 stations in Chongqing during 1951-2009, the climatic variation characteristics, periodicity features, temporal-spatial distribution of the thunderstorms are studied by means of mathematical statistics, wavelets analysis and EOF analysis. The results show that the average annual number of thunderstorm days is 37.48d in Chongqing City and it can occur in any month, mostly in July and August. Thunderstorms mainly happen in summer. Over the past 59a interannual thunderstorm variability was significant and showed a decrease trend with fluctuation, and the decrease was about 3.403d per decade on average. The results from wavelet analysis show that the variation of annual number of thunderstorm days in Chongqing has a short period of 5a, a middle period of 8-9a and a long period of 18a. As for the spatial distribution, the maximum number of thunderstorm days lies in the southeast of Chongqing, the second in middle and northeast, and the minimum in the west. Distribution of thunderstorm shows the characteristics of gradually decreasing from the eastern mountains to the central and western hills. The analysis of EOF shows that the abnormal spatial distribution of thunderstorm in Chongqing can be classified into several types: overall type, local type, longitude type, and latitude type.
国家科技期刊平台
NSTL
万方数据
维普
