降水量突变对汾河流域汛期影响研究

Research on the Impact of Abrupt Change of Precipitation on Flood Season in Fenhe River Basin

传统汛期分期方法计算繁琐且较少考虑气候的变化,为更加科学合理地进行汛期分期,本文采用CSD法检测到1957-2014年汾河流域降水量(p)突变年为1985年,然后以1985年为分界点,应用判别模式法对汾河流域进行汛期分期,并引入均方差评价指标S对各分期结果进行评价。研究表明:由CSD检测法得到汾河流域降水量突变年为1985年,以突变年为分界点,得到1986-2014年主汛期较1957-1985年汛期分期短30天,降水量呈减少趋势的地区,降水量突变年后主汛期会较突变年前缩短。

The traditional calculation method of flood season staging is complex computation and less consideration of the climate change. In order to let flood season staging more scientific and rational,the abrupt change of precipitation(p)in Fenhe River Basin from 1957 to 2014 was detected by CSD method in this paper,which is 1985. Take 1985 as the cut-off point,the discriminant pattern method was used for flood season staging of Fenhe River Basin,and the mean square error evaluation index S was introduced to evaluate the results for all stages. The results show that 1985 is the abrupt change year of precipitation and precipitation in Fenhe river basin,the main flood season from 1986 to 2014 is 30 days shorter than that from 1957 to 1985. The area whose precipitation shows a decreasing trend,the main flood season after the abrupt change of precipitation would be shorter than that before the abrupt change.