Temporal-Spatial Distribution and Variation Characteristics of the Thunderstorms in Xinjiang During 1961-2010
Using the thunderstorm observation data from 89 meteorological stations of Xinjiang during 1961-2010 and the methods of mathematical statistics and linear trend analysis,in this paper,the temporal-spatial distribution and variation characteristics of thunderstorms in Xinjiang are analyzed.The results show that the distribution of thunderstorms in Xinjiang has significant regional features,and the annual thunderstorm days appear more in mountain regions,the northern Xinjiang and the western Xinjiang,rather than plains,the southern Xinjiang and the eastern Xinjiang.The distributions of annual thunderstorms in the west portion of the Tianshan Mountains and their two sides are zonal distribution,forming two areas with 46-84 and 25-35 days annually.Zhaosu in the Ili River valley has the most thunderstorms,up to 83.7 d per year.Temporally,the thunderstorm in Xinjiang is seasonal,primarily appearing in summer,accounting for 77％ of the total.In cold winter,thunders are seldom heard.The monthly thunderstorm days show a distribution of singlepeak.Most thunderstorm days are in July,with six days per month averaged over Xinjiang.The earliest thunderstorm often appears from February to April while the latest one appears from September to December.Recently,the average thunderstorm days decrease significantly,with the decreasing rate of 1.28,1.53,1.90 and 0.82 d ·(10a)-1,respectively,in Xinjiang as a whole,in North Xinjiang,in the Tianshan Mountains and in South Xinjiang.Spatial distribution over most parts of the region presents a decreasing trend,especially,in North Xinjiang.However,in the Tianshan Mountains and their two sides and some places in the west part of South Xinjiang,there is a weak increasing trend.Decadal variation trend of thunderstorms is,in general,going down year by year.Thunderstorm days are all decreasing in spring,summer and autumn,with most outstanding decreasing trend in summer.The monthly thunderstorm days in Xinjiang and their subareas all show a decreasing trend.
NETL
NSTL
万方数据
维普
