西南区域模式在成都地区的降水检验及物理量分析

The SWC-WARMS of the Heavy Precipitation and Physical Quantities in Chengdu

本文选取2014年6～9月西南区域模式产品的每日20 h(北京时)起报的00 h～24 h降水量、相关物理量及成都地区实况降水量。首先利用领域法建立高分辨率模式与稀疏站点对应关系,其次比较领域内的降水量分级传统技巧评分以及强降水(25mm以上)与模式物理量阈值进行概率分析,得出强降水物理量阈值,最后通过个例对模式物理量阈值进行检验。得出如下研究结论:降水量分级评分结果表明模式对成都地区有无降水预报总体效果较好; TS评分随着预报降水量级增大而减小,同时模式空报率高于漏报率;而暴雨及暴雨以上量级降水混合评分为11. 6%,具有一定的参考性。强降水与模式物理量阈值概率分析表明模式对强降水有一定的预报能力,但量级、落区相对较差。两次降水个例物理量阈值均满足以暴雨、暴雨以上降水为主的条件。

The SWC-WARMS predictions of the 24h rainfall,related physical quantities initiated at 20:00 BST and the actual precipitation in Chengdu from June to September of 2014 are used to figure the traditional forecast skill scores for different precipitation levels and analyze the thresholds value of the heavy precipitation(over 25mm)physical quantities by using neighborhoods method to build the corresponding relations between high resolution mode and the sparse site.The inspection results are as follows:The model has a better effect on the appearing of rainfall;Threat Score(TS)of light rain is relatively high,followed by moderate rain,and then heavy rain;Meanwhile,mixed TS of storm rain and above is 11.6%,which has reference value to some extent.Analysis of corresponding physical quantities corresponding to heavy rain shows that SWC-WARMS has certain forecasting ability,but the forecast of magnitude and falling area are relatively poor;the thresholds of physical quantities of the first two precipitation cases all satisfy the conditions of storm rain and above.