| Droughts is a complex natural phenomenon which affected by a series of climate factors.In order to represent the drought index more truly,this paper develop a multi-factors evaluation model for single station and the total region,which based on the researches of quantitative evaluation methods for summer droughts in Sichuan Basin and analysis of main climate factors influencing the assessment drought index instead of the method of counting the length of the drought period.Also the lists of assessment summer droughts index for the single station and the total region are set up.As a result,this new one synthesizing the climate factors,which contain temperature,sunlight,humidity,etc.have great differences with the old index.At the same time,we find that the evaluation result of new model is more coincident with the observations,and can be applied to climate operation well. |