基于多种方法的小型蒸发与E-601型蒸发器蒸发量折算分析及应用

Analysis and application of the Converted Evaporation of Small Evaporator and E-601 Evaporator Based on Multiple Methods

【目的】探明贵阳蒸发量特征,为该市山塘水库蓄水等方面提供参考。【方法】利用贵阳市1983—2001年小型与E-601型蒸发器同期观测资料,运用折算系数法、线性回归法和多元回归法对小型蒸发量进行折算并与E-601型蒸发量对比检验,选择最优方法折算小型蒸发资料延长大型蒸发序列,进而对蒸发量特征进行研究。【结果】小型与E-601型蒸发量之间存在显著相关。气温越高、日照越长、湿度越低、云量越少,蒸发量就越大,反之越低。小型较E-601型蒸发量年平均偏大61.3%,各月偏大43.5%~78.1%。E-601型蒸发器测量的蒸发值更能代表当地气候特征。折算系数、线性回归、多元回归模型均能对小型蒸发量进行较好地折算,为延长大型蒸发序列提供科学依据,其中线性回归法和折算系数法简单快捷,而多元回归模型则更适用于日值折算,计算较复杂。【结论】近62 a来贵阳市蒸发量呈增多趋势,其中上半年趋于减少,下半年趋于增多;结合降水量计算水分盈亏量发现贵阳市夏半年水分盈余集中期出现在5—7月,冬半年水分亏损期长,留冬用水充足。

This paper aims to explore the characteristics of evaporation in Guiyang,and to provide some references for the storage of mountain pond reservoir,etc.,based on the observed evaporation from small-scale evaporator and E-601 evaporator in Guiyang during 1983—2001.Using the conversion coefficient method,linear regression method,and multiple regression method,the evaporation of small evaporator is converted and compared to the evaporation of E-601 evaporator.The optimal method is selected to convert the evaporation data of small evaporator and extend the large-scale evaporation sequence.It has been found that there is a significant correlation between the evaporation rates of small evaporator and E-601 evaporator.Higher temperature,longer sunshine duration,lower humidity and fewer clouds correspond to larger evaporation rates,and vice versa.The annual average evaporation of small evaporator is 61.3%higher than that of E-601 evaporator,with a monthly increase of 43.5%~78.1%.The evaporation value measured by the E-601 evaporator can better represent the local climate characteristics.The conversion coefficient,linear regression,and multiple regression models all provide effective conversion methods for small-scale evaporation,offering a scientific basis for extending the large-scale evaporation sequence.Among them,the linear regression and conversion coefficient methods are simpler and quicker,while the multiple regression is more suitable for daily value conversion but involves more complex calculations.Over the past 62 years,Guiyang City has shown an increasing trend in annual evaporation,decreasing in the first half of the year and increasing in the second half.Calculating the water surplus and deficit combined with precipitation suggests that the concentrated period of water surplus in the summer half year in Guiyang City occurs from May to July while the water deficit period in the winter half year is long,with sufficient water for winter.