An Algorithm Of Classifying Convective And Strariform Pricipitation And Primary Application In Estimating Precipitation

An algorithm for partitioning of radar reflectivity into convective and stratiform rain classifications with China New Weather Radar—CINRAD has been developed. The major contents and conclusions are presented as follows:Firstly, we make a reference to program "SHY95"which was made by Steine to establish a primary technique of classifying convective and stratiform by three facets such as intensity, peaked ness and surrounding area.Secondly, we apply this technique to three datasets that are Typhoon— —Kanou on September 11th ,2005 in Wenzhou, zhejiang Province, a squall line storm weather on Mar 22th ,2005 in zhejiang Province, and a storm weather with large straitiform area on June 23^rd , 2005 in Guangzhou Province. After analyzing the vertical profile of some area, we can draw an conclusion that this technique is logical. It can identify the gyroidal convective during Typhoon , severe line squall, and the vesicle convective which is enchased in straitiform.Thirdly, we make a sensitivity test by changing parameters of the program. It shows that different parameter makes the result differently a lot. So how to chose the peaked ness and surrounding area is an essential while we classify convective and stratiform.Forthly, by analyzing the application of estimating the precipitation on June 19th,2002 in Hefei, we get conclusions as follows: Results of rainfall intensity which was estimated by using only convective Z-I relationship or straitiform Z-I relationship differs ablout 37% from the one estimated by using both convective and straitiform Z-Irelationship after classifying the cloud.Fifthly, after analyzing the application of estimating precipitation lasted from June 19^th to June 20^th , 2002 in Hefei, we got some information about convective and straitiform such as each other's change in cloud area , rainfall intensity, rainfall during 24hours and so on. Then we also can draw an conclusion that Convective plays a very important role in the Mesoscale convective system( MCS).During this dataset, precipitation is mainly caused by convective.Lastly, we come to an conclusion that both convective and stratiform are very important factors in storm. It will make a positive direction for us to promote the precision of estimating the precipitation if we can classify that two ones exactly.