动力模式产品在河南省夏季降水预测中的降尺度应用

Downscaling Application of Dynamical Model in Summer Precipitation Prediction in Henan Province

利用NCEP/NCAR再分析资料和河南省106个站点夏季降水资料,建立了河南省夏季降水降尺度预测模型。该模型利用模式产品的500 h Pa高度场信息,通过统计降尺度方法,对河南省106个站点的夏季降水进行降尺度预测,实现了气候模式产品在河南省夏季降水预测中的降尺度解释应用,弥补了气候模式空间分辨率较低的缺陷。对该模型的历史回报检验表明,该降尺度模型对河南省夏季降水预测效果较好且较为稳定,尤其对北部、西部和豫南南部地区的效果最好。利用BCC-CGCM1和ECMWF-SYSTEM4模式资料,进行了独立样本的检验,结果表明,两种模式在5月起报的预测效果要优于3月起报的预测效果,BCC-CGCM1模式3月的预测效果要好于ECMWF-SYSTEM4的,两种模式在5月的预测效果相当。目前,此方法实现了可视化开发,并集成了检验方法,已应用于河南省气候预测业务中。

Using NCEP/NCAR reanalysis data and observation data of 106 meteorological stations in Henan, the downscaling prediction model of Henan summer precipitation was established. The model predicted the summer precipitation of 106 meteorological stations in Henan by using 500 hPa height field of climate model and downscaling method. The model realized the downscaling application of climate model products in Henan, and made up for the defect of low spatial resolution of climate model. The historical return tests showed that： the downscaling model＇ s had good and stable forecasting effect for summer precipitation in Henan province, especially in north, west and south of Henan province. Using BCC- CGCM1 and ECMWF-SYSTEM4 dynamical model data, test of independent samples for this model was done and resutls showed that ： prediction results of both the two dynamical model＇ s from May were better than that from March. The prediction of BCC-CGCM1 from March was better than ECMWF-SYSTEM4, but the precipitations from May of the two models were similar. Based on this model, we developed a visual system and integrated test methods for using in climate forecast operations in Henan province.