The Research About The Summer Precipitation Prediction In China Based On EEMD Method

Traditional statistical method has difficulty in dealing with climate system which is nonlinear and non-stationary. The Empirical Mode Decomposition (EMD) and Ensemble Empirical Mode Decomposition (EEMD) provide an effective way to stabilize the climatic time series.Now the EMD-EEMD method has been used in nonlinear system analysis,seismic signal analysis,biological medicine and economic fields.By using the monthly precipitation data of24weather stations in the upper and middle reaches of the Yellow River area in summer during1951-2013,the statistical prediction model based on the EEMD,combined forecast and ensemble forecast is built.To extend the application of that method, the monthly precipitation data of160weather stations in the summer during1951-2013is used for the application of the model in prediction of short-time sequences.What’s more,the forecast period is set from6months to1year. To validate the rationality of the model and improve the prediction effect, we select several influential factors of precipitation, and study the relationship between the IMF and factors aiming at improving the accuracy of prediction.The main conclusions are as follows:(1)the model examined by Ps standard has a stronger ability on summer precipitation prediction in the region than climate patterns and traditional statistical method and has higher accuracy and better prospect;(2)as long as the fitting continuation and forecasting method to IMF,the model’s effect is satisfactory;(3)There is a correlation between the IMFs and influential factors of precipitation.