基于物理量参数的伊犁河谷短时强降水预报技术研究

Short-time Heavy Rainfall Forecast Technology Based on Physical Parameters in Ili River Valley

利用2010-2018年6-8月伊宁站每日08、20时探空数据,讨论分析伊犁河谷夏季短时强降水的关键环境参数的阈值,并对2019年夏季短时强降水进行检验评估,结果表明:(1)K≥32℃、k_(m)≥37℃、k_(c)≥37℃、IQ≥2653 g/kg、SW_(2)≤2.3可以作为6月产生短时强降水的判别指标;K≥32℃、k_(m)≥37℃、k_(c)≥37℃、IQ≥2768 g/kg、SW_(2)≤3.1可以作为7月产生短时强降水的判别指标;K≥32℃、k_(m)≥37℃、k_(c)≥36.5℃、IQ≥2673 g/kg、SW_(2)≤3.1可以作为8月产生短时强降水的判别指标。(2)通过检验,所得出的判别指标预报短时强降水,准确率提高了10.4%,而空、漏报率明显减少,说明此指标可以为伊犁河谷的短时强降水潜势预报提供参考。

By using six to eight months in 2010-2018 daily 08:00,Yining stand 20 sounding data,analysed the key physical parameters of the Ili River Valley in summer short-term heavy rainfall threshold,and test the short-time strong rainfall in the summer of 2019 assessment,the results showed that:(1)K≥32℃,k_(m)≥37℃,k_(c)≥37℃,IQ≥2653 g/kg,SW_(2)≤2.3 can be used as the index of short-time strong rainfall in June;K≥32℃,k_(m)≥37℃,k_(c)≥37℃,IQ≥2768 g/kg,SW_(2)≤3.1 can be used as the discriminant index of short-term heavy precipitation in July;K≥32℃,k_(m)≥37℃,k_(c)≥36.5℃,IQ≥2673 g/kg and SW_(2)≤3.1 can be used as the discriminant index for the occurrence of shorttime heavy precipitation in August.(2)Through the test,the accuracy of the obtained discriminant index in forecasting short-time heavy precipitation improved by 10.4%.The false alarm rate decreased obviously,indicating that this index can provide reference for the potential forecast of short-time heavy precipitation in Ili River Valley.