Application of Variational Quality Control to Regional GRAPES-3DVAR

Quality control of observational data is an important and indispensable components in the numerical prediction system.Quality control impacts on the observational data using the numerical weather prediction analysis system,impacts the effect of the initial analysis field,also directly affect the model prediction results.In recent years the variational assimilation has developed,the variational quality control began the widespread use of applied research.The basic idea is based on the quality of the error distribution principles so that the different observations of the variational assimilation in the more reasonable contribution.This article attempts to the variational quality control program applied to Chinese regional GRAPES-3DVAR assimilation system to improve the numerical prediction results.A simulation test is done.It was a rainstorm in southern China from 2 to 3 July.The numerical simulation tests are also done for three months of the summer of 2009.A case testing and continuous results show that: After quality control of the variational analysis is reasonable.Despite the geopotential and wind field changes are not significant,but the humidity field results improved water vapor transmission intensity is adjusted,close to live a more rational analysis of forecast models to improve the initial value of positive significance.Meanwhilet the pattern of precipitation area and forecasting intensity are improved.