Analysis of Distribution and Variation Characteristics of Rainstorm in Xinyang Based on Wavelet Transform
Based on the daily precipitation data of 9 national meteorological observing stations in Xinyang from 1965 to 2020,the distribution and variation characteristics of rainstorm in Xinyang were analyzed by linear regression,MK test and wavelet analysis methods.The results showed that:(1)The average annual torrential rainfall and frequency in Xinyang were 296.9 mm and 3.7 d,respectively,showing an insignificant fluctuating upward trend and a distribution pattern of the more in the south and the less in the north.(2)The monthly mean torrential rainfall and frequency showed unimodal characteristics.Rainstorms mainly occurred in summer and occurred more in spring than in autumn.(3)All the extreme rainfall occurred from late June to early July,and showed a more-less-more-less distribution from west to east.(4)There was a sudden change in 1968,and then the torrential rainfall increased significantly.1981 and 2009 were the years in which the heavy rainfall suddenly decreased,and the annual rainfalls were large in the five years before and after these two years.The years of abrupt change in annual rainstorm frequency were 1966 and 2008.(5)The period of annual average torrential rainfall and rainstorm frequency was relatively short,with a period of 4 years in 1980-1990 and 2 years around 2000.
万方数据
维普
