具有函数型特征的干旱频率分析方法及应用研究

Study on a Method of Drought Frequency Analysis with Functional Characteristics and Its Application

本文依据降水量距平百分比的游程理论,采用1986-2016年安徽省六大水文站点降雨量数据进行干旱识别,应用函数型数据分析方法拟合修匀干旱历时(D)与干旱烈度(S)的频率分布曲线,并根据重现期研究干旱事件的特征与时间、流域、气候之间的关系.结果表明,干旱平均历时整体趋势由北向南逐步减小,干旱烈度受气候影响明显,温带气候所受干旱更严重;函数型数据分析方法所得到的干旱历时与烈度频率分布曲线与普通方法的拟合函数曲线相比较更加接近样本点,具有较理想的拟合效果;随着重现期的增加,干旱烈度与干旱历时呈减轻趋势,干旱发生的频次越严重,再次发生干旱的可能性越低.

Based on the run theory and precipitation data of the six major hydrological site in Anhui Province from 1986 to 2016,the drought was identified.Meanwhile,the functional data analysis method was applied to fitting smoothing frequency distribution curve of drought duration(D)and drought intensity(S).According to the recurrence period,the relationship between the characteristics of the drought event and time,basin,and climate was studied.The results showed that the overall trend of average drought duration decreased gradually from north to south,and the drought intensity was significantly affected by climate,while the drought intensity was more serious in temperate climate;the distribution curve of drought duration and intensity frequency obtained by the functional data analysis method was closer to the sample point than the fitting function curve of the ordinary method and also had a better fitting effect;with the increase of the recurrence period,drought intensity and drought duration showed a decreasing trend,and the more severe the frequency of drought,the lower the probability of drought occurring again.