Comparative Analysis Of Xiangyu Radar Network Puzzle And CINRAD Network Observation In Shanxi Province

The new generation weather radar in China(CINRAD)uses the VCP21 volume scanning mode when it is in business work,making the radar to be the blind to the area below the minimum elevation angle,the area between different elevation angles and the static cone area above the highest scan elevation angle.Moreover,influenced by the curvature of the earth,there is a great blind area in the range from 0km to 3km above the surface,while the space below the height of 3km is a area where the atmospheric activity is very active.Many mesoscale weather originates in this space area,and severe weather disasters,such as tornado and wind shear,are all started below 1km.All solid state X band weather radar has the advantages of small size,low cost,convenient erection,long time work and so on,which makes the all solid state X band weather radar widely used.The use of all solid state X band weather radar to form a radar network can be used as a supplement to the new generation of weather radar,and it is mainly used to observe the weather echo within 3km of the ground.This paper is mainly aimed at organizing network mosaic of all solid state X band weather radar in Shanxi province and comparing it with the new generation CINRAD radar,analyzing the reflectivity factor observed in the common detection area,and then analyzing the rationality of the whole solid X band weather radar network to detect the weather target,and exploring the complementary effect of the X band radar to the new generation weather radar.The main work of this paper is as follows:Determine the analysis network radar.According to the information of the five C band new generation weather radars and 10 auspicious rain all solid state X band weather radar stations in Shanxi Province,such as the latitude and longitude,altitude,the maximum detection distance,the distance resolution and so on,the radar detection range is made.Then the X band radar(Qixian,Taigu and Shouyang)which can be rationally analyzed and set up combined with the corresponding C Band New Generation Weather Radar(TaiYuan Railway Station radar)can be selected.Determine the comparative analysis area.According to the longitude and latitude of the selected all solid X band radar and the C band new generation weather radar station,and the height data of the SRTM terrain in Shanxi Province,the ISO beam height map at different heights is made,and the small common detection area of the radar beam is blocked by the ground objects.Then the terrain of C band new generation weather radar and different X band radar lines and the intersecting of radar beam are determined,moreover,the common detection area between different radars is determined without beam blocking,which determines the region when a number of contrast analyses are carried out.Comparative analysis of reflectivity factors on radial,vertical and contour surfaces.According to the scanning data of all solid state X band weather radar and C band new generation weather radar,the reflectivity factor of two radars is read out.And the contour line,vertical section and the equal high plane position display(CAPPI)map of the reflectivity factor in the common detection area along the distance are generated.The CAPPI map of the same height of different X band radar is used to make a network mosaic,and the qualitative and quantitative comparison analysis is made with the reflectivity factor of the C band new generation weather radar at the same time.The following conclusions are drawn:(1)under the complex geographical conditions of Shanxi Province,the reflectivity factors of the three X band radars in Qixian,Taigu and Shouyang station are more consistent.(2)there is a certain difference in the detection results between the new generation X band weather radars of the single all solid state and the new generation C band new generation weather radar at Yuan station.This is because the X band radar is all solid state radar,and different pulse modes are adopted inside and outside 20 km.Therefore,there is a significant difference between the value of the X band radar and the Taiyuan radar within 20 km,and the difference between the regions of the X band radar outside 20 km is small,and the difference can be corrected by the system calibration.(3)through the network comparison,we can see that after joining the X band weather radar network,a wider range of precipitation echoes can be observed;(4)the reflectivity factors of the new generation weather radar in the C band are generally small.The reason of the difference should be that there are some differences between the two different types of radar calibration.It is suggested that the different types of radar should be calibrated before the business application.