Study of BiasCorrection in T213 Global Ensemble Forecast
In view of existence of model systematic error, a study of biascorrection has been done to estimate and reduce systematic error. Onemoment biascorrection has been introduced in this paper. The merit of this method is that quantity of samples needed is smaller, thus estimation and biascorrection could be carried out quickly and economically. Onemoment biascorrection towards T213 global ensemble forecast of 500 hPa height, 850 hPa temperature and 2m temperature has been done. Verification towards raw forecast and biascorrected forecast shows that ensemble member homogeneity and cold bias have been improved, and ensemble mean RMSE and ACC also have been improved, especially bigger systematic error of 2m temperature forecast has been improved obviously.