基于大气环流和海温场的降水组合预报模型

A precipitation combined forecasting model based on atmospheric circulation and sea surface temperature

针对降水具有混沌性和随机性,准确进行长期降水预报难度高的问题,提出时变海温多极指数和因子预报意见指数,基于大气环流和海温场构建长期降水组合预报模型,以三峡水库流域为例进行了验证。结果表明:组合预报模型在三峡水库流域1961—2020年汛期的月降水预报中有较好的适用性,特别在6月和9月降水预报上表现优异;与多因子回归、随机森林数理统计模型和CFSv2、ECMWF system 4动力数值模型相比,该模型更为稳健、预报精度提高显著。

In view of the chaos and randomness of precipitation and the high difficulty of accurate long-term precipitation prediction,the multiple time-varying sea-temperature index and factor prediction opinion index were proposed.Based on the atmospheric circulation and sea surface temperature(SST)field,a long-term combined precipitation forecasting model was constructed,which is verified by taking the Three Gorges Reservoir Basin as an example.The results show that the combined forecasting model has good applicability in the monthly precipitation forecast of the flood season from 1961 to 2020 in the Three Gorges Reservoir Basin,especially in June and September.Compared with multi-factor regression,random forest mathematical statistical model and CFSv2,ECMWF system 4 dynamic numerical models,this model is more robust and has significantly improved prediction accuracy.