Research On Local Precipitation Observations Based On Microrain Radar And 2DVD

As an important aspect of raindrop spectral distribution,the study of vertical distribution of precipitation is helpful to improve people's understanding of the variation characteristics of precipitation in vertical height.The precipitation detection instrument used in this study includes a micro rain radar(MRR)and a surface raindrop spectrometer 2DVD.The vertical distribution and evolution characteristics of mixed and layered precipitation processes observed jointly by the two in Chengdu area are studied.Firstly,the quality of observation data is controlled,and the rainfall attenuation is compensated and corrected by the method of database by database.Then,the MRR near ground detection results are compared with 2DVD to discuss the reliability of the MRR low-level data.Then the average vertical distribution characteristics of the characteristics and raindrop spectrum of different precipitation processes and different precipitation stages are studied,and their evolution characteristics from time and space are also analyzed.The main results are as follows:(1)It is effective to adopt the method of database by database correction to correct the attenuation phenomenon existing in the detection of precipitation,which conforms to the empirical formula and helps to improve the reliability of the data of the micro rain radar.(2)The hourly accumulated rainfall of three lower altitudes detected by MRR is greater than 2DVD detection results.In mixed precipitation,the observation results of MRR at the drizzle end are higher than 2DVD,and the observation results at the drizzle end are slightly lower than 2DVD,while the observation results for medium raindrops are highly consistent.As a whole,MRR has a good detection effect on Raindrop Spectrum Distribution in mixed and layered precipitation,which is consistent with the structure of raindrop spectrum distribution detected by 2DVD on the ground.(3)The vertical variation of precipitation characteristic quantity and raindrop spectrum in different rainfall intensity stages is obvious.In the stable weak precipitation stage,the raindrop spectrum changes little in the vertical direction,and the raindrop spectrum width is narrow;in the strong precipitation stage,the raindrop spectrum width is obviously widened,and the concentration of medium and large drops increases with the decrease of height;in the precipitation dissipation stage,the concentration of small drops decreases with the decrease of height,and the concentration of medium and large drops changes little in the vertical height.(4)Because of the small rainfall intensity and the small change of rainfall intensity in layered precipitation,the average raindrop spectrum detected by MRR changes little in the vertical height.As a whole,the detection effect of MRR on raindrop spectrum distribution is better than that of 2DVD,and the detection deviation of MRR to layered precipitation is smaller than that of mixed precipitation.