青海省短时强对流天气雷达自动预警技术应用初步研究

Preliminary study on application of radar auto-warning technology to short-time strong convective weather forecasting in Qinghai

针对WSR-88D冰雹算法虚警率较高,且可修改的可调参数有限的缺点,根据青海省短时强对流天气的雷达预警指标,自动识别强对流云和发布强对流天气预警(简称自动预警技术)。使用雷达体扫基数据,将自动预警技术初步应用于2010年青海省东部12个强对流风暴日过程,并与基于WSR-88D风暴产品的人工预警结果进行对比分析。结果表明:自动预警平均比实况提前时间大于25 min,其数据处理效率和预警正确率远高于人工预警;自动预警技术的降水预警正确率为91%、虚警率为9%,而人工预警的降水预警正确率75%,人工与自动预警的降雹正确率均为100%。在短临天气预警预报业务中,将自动预警技术作为WSR-88D算法的辅助识别技术,可进一步提高强对流天气预警预报的正确率和提高短临天气业务的自动化程度。

Aimed at the two drawbacks of hail algorithm （88D）： the high false acceptance rate （FAR） and the limited revisable parameters, an automatic warning （AW） technology which can distinguish the strong convection cloud and release the warning signal automatically is in- troduced in this paper. Using the base data of volume scanning of radar, the AW technology is applied to 12 strong convection weather pro- cesses in the east of Tibetan Plateau in 2010 and then the data gotten by the AW technology is compared with the data gotten by manual warn- ing based on products of 88D. The results show that the data handling efficiency and warning accuracy of AW are considerably higher than that of manual warning. The AW release time is 25 minutes earlier than the occurrence time of the actual weather on an average. The precipi- tation accuracy of AW is 91%, FAR is 9% while the precipitation accuracy of manual warning is 75%. In term of hail events, the accuracies of both AW and manual warning are 100%. In conclusion, the accuracy of short-time strong convective weather forecasting and warning would be further improved and the degree of automation of short-time weather forecasting would be developed through putting the AW technology into algorithm （88D） as an assisted technology.