Extended Abstract

Research and Operation on Quantitative PrecipitationForecast (QPF) in DPR of KoreaKIM thaejinCentral meteorological research institute , DPR of Koreashma@co.chesin.com.The dy namic me thod, the em piric an d statistic method , the short-time ex trapolationmethod by using of synoptic observations were used for QPF in the past few years.In the dynamic method the amount of precipitation is determined as the accumulation byhorizontal trans port o f v apor an d the con densation by vertical m otion o f air. In case ofheavy rain , the la rge scale factors, me dium and me so-scale factors by to pography a ndconvection instability were added to them .In the empiric and statistic me thod, the distribution of the precipitation amount, analyzedwith seasons and pressure systems, was used for the corresponding region forecast andthe discriminant r egression equation was m ade out for the class ified forecast ofprecipitation amount.The principle component analysis and the cluster method were developed and used forthe medium rage 5 days forecast.In the recent days with the rapid development of numerical weather forecast, the study fortransfer-methods by using NWP output is being carried out.The BP multi-layer structu re o f Neural Network is d esigned and is implementedoperationally now. In this method, the amount of precipitation is divided by several gradesand forecasted su ccessively by o ccurrence p robability of each g rade, b ut the resultsobtained are not yet reached to the satisfied level.On the other hand, on the basis of analysis on atmo sphere background and cloud datafrom satellite, which cause heavy rain in some region, the conception model for rainstormoccurrence is developed and used for very short range forecast.The research for higher resolution of time-space scales at QPF is being studied now but ithas som e dif ficulty at the co nsideration o f medium a nd meso scal e di sturbance anddetailed topographic factors.It would b e expected that the reasonable choice of the fa ctors that fu lly present regionalprecipitation amount is necessary for QPF, which requires more study such as sophisticatedanalysis on observation and NWP output, some numerical simulation for singular processand the introduction of advanced model.-319-