日本数值产品对丹东暴雨预报的天气学检验与误差分析

摘要

使用2001年7月—2010年8月日本数值模式传真图资料,以辽宁丹东为代表站点,采用统计学与天气学检验相结合的方法,对日本数值模式暴雨预报性能和误差进行检验和分析。同时,对日本数值模式高空环流形势、中低层影响系统及物理量场预报进行检验。结果表明：1）日本数值模式对暴雨预报的TS评分为21.8%,具有一定预报能力;预报正确率较低,仅23.8%,空报率也较低,为24.0%,命中率则高达76.0%。2）日本数值模式暴雨预报误差表现在预报量值偏小和落区偏差,其中对气旋（倒槽）型暴雨预报最好,对冷涡型暴雨预报最差。3）对不同季节暴雨预报有所不同,春季、夏季漏报多,秋季易出现空报。4）日本数值模式对欧亚中高纬地区环流形势预报较准确,对西风槽预报略偏西、强度偏弱、槽底位置偏北1个纬度;对低涡的位置、强度预报与分析场吻合,但范围偏小;对850 hPa低空急流的位置、最大风速值以及700 hPa垂直运动上升区中心值、位置的预报,与实况偏差不大。%Based on Dandong weather station in Liaoning province,the numerical prediction facsimile data of the JMA model from July 2001 to August 2010 and the statistical and synoptic methods were used to verify and analyze the heavy rain forecast capability and error of JMA model,and verify the JMA model＇s forecast capability for upper-air circulation,synoptic influence systems in the middle and lower level and physical quantity field.The main results are as follows.The capability of JMA model on heavy rain forecast is limited and the threat score of forecast is 21.8% with the low forecast accuracy rate（23.8%）,forecast vacancy rate（24.0%） and high hit rate（76.0%）.The forecast error of the JMA model on heavy rain shows the precipitation value is less and there is a deviation for distribution of rain and,the forecast capability on the heavy rain caused by the cyclone or inverted trough is the best but that caused by cold vortex is the worst.The forecast capability of JMA model on heavy rain varies in different seasons,and the miss rate of heavy rain is higher in spring and summer and the heavy rain false alarm easily appears in autumn.The JMA model shows a better forecast capability on Eurasian circulation situation in middle-high latitude,with further west position and weak intensity and 1 degree in latitude northwards for trough bottom of westerly trough.Meanwhile,the prediction of location and intensity of low vortex is consistent with the respect of the analysis fields,but the range is relatively smaller,while the prediction of the location,the maximum wind velocity of low-level jet at 850 hPa and the location and central value of vertical updraft motion area at 700 hPa is similar to the actual value.