The Adaptive And Optimal Z-I Relation Model With Distance-Azimuth Comprehensive Factor Of Optimized Regional Rainfall Estimation By Radar

In the various elements of the atmosphere changing, precipitation is one of the more important meteorological elements. Accurate quantitative estimate area precipitation is very important for disaster prevention, mitigation and the precipitation forecast. Although precipitation station can be measured directly with a single point of continuous rain changing over time, but the density precipitation station is sparse and the spatially varies of rainfall is complex, the measuring of precipitation cannot accurately reflect changes of precipitation in space. Radar has a wide range measuring and high resolution of spatial and temporal. And radar can get quantitative precipitation information in a large area. More and more people put the concern in the study of using radar gauge to estimate regional rainfall. And this is an important way for measuring regional precipitation.In this study, taking Anhui province as the research area, using the data of Six band of Doppler weather radar in the city of Hefei, Anqing, Huangshan, Bengbu, Fuyang and Nanjing, and precipitation in 1 hour from weather stations in Anhui province, basing on two kinds of factors, the distance from weather stations to radar centers and the located radials of weather stations in radar observation, establish the models of Distance-Azimuth adaptive radar quantitative change Z-I relation of rainfall estimation. Then interpolate the parameter of Z-I for the weather station, we can obtain the quantitative spatial distribution of regional rainfall with the radar initial field. Through the above work of fitting the surface precipitation and accuracy assessment the model, we can conclude that:(1) For keeping the time consistency and spatial consistency between rainfall stations and radar data, we choose eight ways to obtain the radar echoes initial field from parsing radar base data. Then we fit of precipitation by direct statistics, and compares and analysis of each radar initial field. Finally we found that the radar echoes initial field by the way of the first average elevation model and time weighted average has smallest error and standard deviation, and fits for the best effect.(2) In this article, by analyzing the surface rainfall spatial distribution of this models, we found that the Distance-Azimuth Comprehensive model closest to the actual distribution of rainfall.(3) From the different types and times of precipitation, we comparative analysis of the Distance-Azimuth model and relational model NEXRAD Z-I, find the Distance-Azimuth integrated model fits better estimation process and the ability rainfall optimal method than the categorical good.