An Application Research On Weather Forecast And Modification By Doppler Radar

On basis of the rationale of Doppler radar sounding precipitation, intensive convection, weather modification as well, utilizing radar basic and second products, some practical research are deployed on precipitation estimate, strong convection diagnosis, rain stimulation and hail suppression by artificial, which provide direction on localization of Doppler radar application, quantification rainfall, strong convectional weather short-time prediction and weather modification. There are four sections mainly in this paper.(1) Optimizing radar rainfall products. Adjusting the Z-I relation of local combined scanning sections and different reflectivities, integrating rain gauge data, the rain products are optimized by means of optimization interpolating algorithm, Kalman filter, etc. whereby their quality have obviously improved.(2) Quantifiable rainfall automatic short-time forecast. The moving speed of different echos are calculated using cross correlation and inducing airflow methods, the any point and area 1-2 hours amount of precipitation are computed according to extrapolation and localization Z-I, dBz-I relations, by which quantificational rainfall short-time forecast can be automated.(3) Character analyzing of radial divergence of intensive convectional echo. The radial divergences of convective cell are calculated adopting different divergence formula in polar coordinate, the corresponding relation are realized between echo intensity and radial convergence, a result is found that the variety of convergence of strong convective echo are a little ahead of change of echo intensity.(4) Based on the parameters of activator concentration getting from numerical experiment of weather modification, the VIL (vertical integration liquid) and ET (echo top) is applied in formula to calculate the bomb amount in rocket-rain-increasing and hail suppression, the problem is solved of estimate operational volume and its containing water in convective clouds, an elementary scheme is suggested of quantificational calculating bomb amount of rain-increasing or hail suppression.