A Study on Quantitative Radar Rainfall Measurements by the Method of Set-pair Analysis

This paper introduces the basic principles of Set-pair Analysis, and presents a method of applying Set-pair Analysis in determining the two parameters of Z ~ I relationship of radar rainfall measurement. This method is then applied in the Bailianhe catchment. After a comparative study between the Set-pair Analysis and the traditional method of CTF, a conclusion is made that, compared with the traditional method of CTF, the parameters selected by Set-pair Analysis can produce better rainfall results. It can not only improve the precision of the total accumulated rainfall, but also decrease the bad effect that the irrational radar reflectivity and actual measured rainfall data pairs brought to parametric optimization. At the same time, it improves the fitting precision of the rational data, which consequently improves the rationality of the two parameters.