通辽市暴雨过程时空分布特征分析

Time and space Distribution characteristics Analysis on the Rainstorm process in Tongliao Area

使用通辽市11个国家级气象站自建站到2015年的逐日降水量资料,共统计出暴雨过程301次,其中区域性暴雨天气过程79次。对其时空分布进行统计分析,其结果表明:(1)通辽市暴雨出现在4—10月之间,主要集中在夏季的6—8月,以7月最多、8月次之;(2)近65a没有明显的增减变化趋势,但阶段特征明显。20世纪60—70年代暴雨过程的年际波动比较平稳,80—90年代波动较大,其中,1994年暴雨过程最多,为13次。进入21世纪以来暴雨过程比20世纪略有减少。(3)从年代际变化看,20世纪90年代暴雨过程总次数最多,为63次,60年代次之;2010—2015年最少,仅发生4次。(4)年暴雨发生频率的空间分布特征是,在扎鲁特旗站维持一个多暴雨中心,在青龙山—库伦—科左后旗至科左中旗站一线分布着一个多暴雨带;在霍林郭勒站有一个少暴雨中心,在奈曼—开鲁—科左中旗西部的舍伯吐站一线存在一个少暴雨带,这种分布与通辽市地形密切相关。

Using 11 national station daily precipitation data of the Tongliao city from the data beginning to 2015,301 times rainstorm process were counted,among them,including 79 times regional rainstorm process.Its time and space distribution was counted and analyzed,the results show that:(1)In Tongliao area,rainstrom occurred between April and October,concentrated mainly in the summer from June to August,the most in July,followed by August;(2)There was no obvious increase or decrease trend in recent 65 a,but the stage characteristics was obvious.The interannual fluctuations of rainstrom process numbers was relatively stable from the 1960 s to the 1970 s,it’s large from the 1980 s to the 1990 s.Among them,rainstrom process were the most in 1994,occured 13 times.The rainstorm process has decreased slightly since the century than the last century.(3)From the interdecadal changes,the total numbers of the rainstrom were the most in the 1990 s,it occurred 63 times,followed by the 1960 s;it were the least from 2010 to 2015,only 4 times.(4)The spatial distribution characteristics of the annual rainstorm frequency was that maintained a rainstorm center at Zalut station,there was a heavy rainstrom belt along the line from Qinglong shan-Kulun-Kezuohouqi to Kezuozhongqi Station.That was a little rainstorm center at Huolinguole Station,a little rain belt was distributed along the line from Naiman-Kailu to SheboTu station in the west of Kozuozhongqi,this distribution was closely related to the terrain of Tongliao City.