Statistical downscaling of the precipitation multimodel ensemble forecast

Based on the TIGGE data sets and theTRMM/3B42RT rainfall product during the period fromJune 1 to August 27 , 2007 ,several statistical downscaling schemes are applied to the ensemble mean rainfall forecasts made by the European Centre for Medium-RangeWeather Forecasts(ECMWF),the Japan MeteorologicalAgency(JMA),the National Centers for Environmental Prediction(NCEP) and the UK Met Office(UKMO)and to their multimodel ensemble products.The results show that the statistical downscaling may improve the forecast effect of each single model. After the downscaling, the root-mean-square errors (RMSE) of the forecasts are significantly reduced, and the Anomaly Correlation Coefficients(ACC) between the forecasts and theTRMM data become larger.The downscaling of the multimodel ensemble forecasts is superior to that of the single model interms of forecast capability of the precipitation maximum.