摘要
基于汾河流域19个气象站点1959—2007年汛期(6—9月)的降水数据,采用小波分析、M—K突变分析及其它数理统计方法,对汾河流域汛期降水量时间序列进行了多时间尺度特征分析。结果表明,近49a来,流域汛期降水呈现减少趋势,递减率是9.79mm/10a,其中6月份的降水呈现上升趋势,速率为2.79mm/10a,7—9月均表现出下降趋势,最明显的是7月份(速率为-6.54mm/10a),7和9月份降水明显减少是流域汛期降水量下降的主要原因;汛期降水在1978年以后发生突变,流域降水处于一个相对少雨的时期;汛期降水量存在8～15a和3～7a的特征周期,中心时间尺度为2,5,10和12a,其中约5a的周期振荡最为强烈,是汛期降水变化的主要周期;根据5a周期及其它特征周期的小波系数变化趋势,估计汾河流域在研究时间段以后近期内汛期降水量可能偏多。
Based on the flood season（from June to September） precipitation data from 19 climatic stations within the Fenhe River Basin from 1959 to 2007,and using wavelet transform method,Mann—Kendall and other statistical methods,a time series analysis was made on the precipitation.The results showed that the precipitation in flood season in the Fenhe River basin showed a declining from 1959 to 2007,with an average velocity of-9.79 mm/10 a.However,the precipitation in June increased with a rate of 2.79 mm/10 a,while it decreased with a rate of-6.54,-2.69,-3.36 mm /10 a respectively in July,August and September.This indicated that the precipitation decreased in July and September was the main source of precipitation reduction in flood season.An abrupt change in the flood season precipitation appeared after 1978 when the basin underwent a period of little rain.From 1959 to 2007,there existed 8 to 15 years and 3 to 7 years cycles of precipitation series in flood season and the significant time-scale change were 2,5,10 and 12 year.But the 5 year scale was the main cycle because its oscillation was most strongly.According to the trend of the wavelet transform result,it can be estimated that there will more precipitation in flood season in the near future in the Fenhe River basin.
出处
《水土保持通报》
CSCD
北大核心
2011年第6期121-125,共5页
Bulletin of Soil and Water Conservation
基金
长江水利委员会水土保持局项目"南水北调中线水源区水土保持预防保护工程对土壤侵蚀
植被恢复和饮水质量影响的研究"(105152)
关键词
汛期
降水序列
小波分析
汾河流域
flood season
precipitation series
wavelet analysis
Fenhe River basin
