Temporal Variation Characteristics And Response Analysis Of Annual Precipitation And Runoff In Luanhe River Basin Based On Quantile Regression

By now,there have been many scholars studying on the change characters of precipitation and runoff series,using plenty of methods like statistical approaches,trend analysis and simulation methods and so on.Seen from the results,we can know that precipitation and runoff series indeed have changed in some way,especially runoff series.In the basin controlled by Panjiakou reservoir,the change characters of precipitation and runoff series are also analyzed by many researchers,in this article we also want to analyze this but using a different method named quantile regression method.Although achievements have been made to study the change characters of precipitation and runoff series,the quantile regression method is rarely used in this area,it's widely used in mathematics,economics,and medicine fields,which providing a new thought for the study of hydrology.Compared with other methods,the condition in the process of using quantile regression method can be more loose,and the results are less susceptible to the interference of outliers,which are resistant and abundant.According to the solving process of this method,there is no need to use any copula to identify the relation between the mean and variance of the dependent variable,making the method more flexible.In this article,we use the quantile regression method to analyze the change between precipitation and runoff series,the main research contents are as follows:(1)Based on these advantages of quantile regression method,this article first uses this method to analyze the regression results of precipitation and runoff series in the basin controlled by Panjiakou reservoir in high or low quantiles,which represent the change characters of different series in the distribution of tails,from which we can know the influences of climate change and human activities qualitatively.(2)Then we work on analyzing the distribution change of these series,the analysis is based on the regression results in percentiles,then empirical distribution function and the probability density function curve of given years are gained from this,the change characters of series can be known from those curves in different years.(3)At last,we make comprehensive analysis about multiple factors that result in the change of runoff,so the multiple quantile regression analysis is proposed for the analysis of runoff change,which can get information from quantitative angle.(4)This article put forward the quantile regression method to analyzing the change characters of precipitation and runoff series in different angles,which making the analysis more comprehensive compared to the traditional methods.From the results,the runoff series have significant reduction in this area,we should pay high attention on the series of problems caused by the change,results in this article also provide certain reality for introducing policies and edicts by relevant departments.