1975—2014年本溪地区暴雨日数变化趋势分析

Analysis on Change Trend of Rainstorm Days in Benxi Area From 1975 to 2014

利用1975—2014年本溪地区4个国家地面气象站逐日降水资料,采用线性趋势系数法、Mann-Kendall突变分析法和Morlet小波分析法对本溪地区暴雨时空分布及变化规律进行分析。结果表明:1975—2014年间,本溪地区暴雨多发于7—8月,呈现南多北少的特点,中心位于西南部的草河口和东部的桓仁;年均暴雨日数5.2 d,年均影响范围8.4站次;40年间本溪地区年均暴雨日数年代际增长显著;暴雨日数年际变化较大,呈缓慢增长趋势;经突变分析发现,1984年前后暴雨日数发生突变,目前处在显著上升期内,但由小波分析发现未来5~10年本溪地区暴雨日数可能逐渐减少。

Based on the daily precipitation data from 4 meteorological stations in Benxi area from 1975 to 2014,finear trend analysis,Mann- Kendall analysis and Morlet wavelet analysis methods were used to study the temporal and spatial distribution and change trend of rainstorm clays in Benxi area. The results showed that from 1975 to 2014,the rainstorm was more likely to appeare between July and August ,more in south and less in north. The rainstorm center was located at Caohekou and Huanren. The annual rainstorm days were 5.2 days,and annual influence ranges were 8.4 stations. During 40 years, the deeadal rainstorm clays showed a significant increasing trend, the annual rainstorm days changed greatly, and increased slowly. With sudden change analysis ,it was found that rainstorm days changed suddenly in 1984 ,rainstorm clays are in rising period at present. Morlet wavelet analysis showed that rainstorm days might appear a declining period in Benxi area in the next 5-10 years.