The radar reflectivity is calculated,and the Z～R relations fitting the snowfall in the Qilian Mountains are got.

Using the typhoon base data of Dopplar weather radar and Zhejiang automatic precipitation station data in 2004 and 2005,the Z-R relation of typhoon precipitation suiting the local area is set up,which is confirmed to be available.

Based on the typhoon basic data of Doppler weather radar in Zhoushan and Zhejiang automatic precipitation station data by using,the Z-R relation expression of typhoon precipitation suiting Zhoushan district is set up and then modified.

Study on the Surface Raindrop Spectra Features and Z-I Relationship in Spring and Summer in Harbin;

Then SPA and its advantages are presented and applied into the determination of the Z-I relationship of radar rainfall measurement.

According to the echo intensity scan data per 6 min and 9 ground stations relevant rain intensity data of 120 km scan range supplied by the new weather radar of Zunyi during the 32 times rainstorm in 2007,the study used the least square method to fit the data and set up the Z-I relationship suited for Zunyi during the rainstorm process.

It is found changes of regression parameters A and b that there is heteroskedasticity in the Z-I relation due to its nonlinearity and instability,and the methods of weighted least square and best criterion function are proposed to slove this problem.