一组雷达预警指标在2013年短时强降水中的应用分析

利用一组雷达阈值指标,对2013年四川盆地发生的5次区域性暴雨过程中的短时强降雨进行检验和订正,结果表明,(1)无论针对具体的站点,还是区域面上的短时强降水,预警指标对预警短时强降水是可行的,且预警时效在0~2h内效果较佳。(2)SWAN产品中分析显示,要产生20mm/h以上的短时强降水,满足预警指标的回波需要监测到3个6min以上,通常强回波持续越长,对应的雨量也越大。(3)针对降水面上的预警准确率除2013年7月04日15时的成功预警率在57.1%左右,其余过程中预警指标对未来1h短时强降雨的预警成功率基本在80%以上,误报率基本在20%以下,在误报的站点中,SWAN拼图中回波与单站雷达探测的回波,尤其是在低仰角度上存在较大误差。

Application Analysis of a Set of Radar Warning Indicators in Short-time Severe Rainfall Process in 2013

Using a set of radar warning indicators, it is inspected and corrected the warning indicators by using examples of short -time severe rainfall process occurred in 2013 in Sichuan Basin, the results show that, 1 ） whether the specific observed station, or Spatial distribution of short - time severe rainfall , warning index is feasible for early warning short - time severe rainfall and early warning of time effects is better in 0 -2h. 2） analysis of SWAN products showed, to produce more than 20mm/h of short - time severe rainfall, meet the warning index echo need to monitor more than three times 6min, usually the strong echo lasts longer, the rainfall is greater. 3）In addition to the successful early warning rate is about 57.1% at 15：00 on July 4th, 2013, other examples of early warning indicators of future lh short - time severe rainfall prediction success rate above 80%, false rate is below 20%. In the false station, echo of the SWAN system puzzle and radar echo of monostatic radar detection had some errors, especially in low elevation angle of radar.