摘要
基于西昌多普勒天气雷达观测资料,分析2006—2013年凉山州境内24块冰雹云特征。结果表明：冰雹云的雷达特征均满足回波强度超过50dBz,回波顶高超过-30℃层高度,45dBz回波顶高超过-10℃层高度,垂直累积液态含水量超过8kg·m^-2。上述4项雷达参数特征在判别冰雹云的时效性上存在差异,回波强度超过50dBz,回波顶高超过-30℃层高度,45dBz回波顶高超过-10℃层高度等3项判别指标对冰雹云提前判别预警时间为4-40min,垂直累积液态含水量超过8kg·m^-2则对冰雹云提前判别预警的时效性效果不佳。与25例短时强降水个例对比发现,45dBz回波顶高超过-10℃层高度作为冰雹雷达预警判别指标有较好的指示作用。
Based on the data from Xichang Doppler weather radar, the characteristics of 24 hail clouds from 2006 to 2013 in Liangshan are analyzed. The results show that all hail clouds have some common features： maximum reflectivity is above 50 dBz; echo top is higher than the height of --30 ℃ level; the height of 45 dBz echo top is higher than the height of --10℃ level; and the vertically integral liquid water is above 8 kg.m 2. The hail clouds can be distinguished according to such features as maximum reflectivity being above 50 dBz; echo top being higher than the height of --30℃ level; the height of 45 dBz echo top being higher than the height of --10 ℃ level, with a lead time of 4 min to 40 min for early warming. The vertically integral liquid water being over 8 kg· m^-2 is not good to early identification of hail clouds. Comparison with short-time heavy rainfall, the height of 45 dBz echo top being higher than the height of --10℃ level is useful for early identification of hail clouds.
出处
《气象科技》
北大核心
2016年第2期252-258,304,共8页
Meteorological Science and Technology
基金
中国气象局新技术面上推广项目(CMATG2010M21)及(CMAGJ2015M51)资助
