摘要
选取2016-2017年青海省西宁市及海东地区的30次降雹过程雷达和闪电定位仪数据,对冰雹天气的雷达回波演变和闪电特征进行分析,重点分析正、负地闪的数量、频次、极性和强度的变化规律,并选取个例对冰雹云发生前后闪电、雷达参数变化进行分析。在冰雹云形成、消亡的过程中,负地闪占绝对优势,正地闪出现频率很少,且分布不集中,这与北方地区冰雹出现时高正地闪频次特征不同。正地闪出现的位置和时间与降雹位置和时间没有明显对应关系。从时间和位置上分析,对流发展初期,负地闪在空间上稀疏出现,随着对流的发展,负地闪分布趋向集中,负地闪集中区域主要集中在组合反射率强度较大的区域且频次存在明显增加。闪电频数的变化和空间分布特征,在强对流天气监测和临近预警中有一定的参考作用。
The radar and lightning locator data of 30 times hailfall process in Xining city and Haidong area of Qinghai Province from 2016 to 2017 were selected to analyze the radar echo evolution and lightning characteristics of hail weather,the variation rules of the number,frequency,polarity and intensity of positive and negative cloud-to-ground lightning are emphatically analyzed,and the changes of lightning and radar parameters before and after the occurrence of hail clouds are analyzed with individual cases.In the process of formation and extinction of hail clouds,negative cloud-to-ground lightning occupies an absolute dominant position.The occurrence frequency of positive cloud-to-ground lightning is very small and its distribution is not concentrated,which is different from the characteristics of high positive cloud-to-ground lightning when hail appears in northern regions.The location and time of positive cloud-to-ground lightning have no obvious correspondence with that of hail.From the perspective of time and location,in the early stage of convection,negative cloud-to-ground lightning appears sparsely in space,with the development of convection,the distribution of negative cloud–to-ground lightning tends to be concentrated,and the negative cloud-to-ground lightning concentration area is mainly concentrated in the area with high combined reflectivity and the frequency increases significantly.The variation of lightning frequency and its spatial distribution can be used as a reference in severe convection weather monitoring and near warning.
作者
颜海前
张玉欣
康晓燕
王启花
张博越
YAN Hai-qian;ZHANG Yu-xin;KANG Xiao-yan;WANG Qi-hua;ZHANG Bo-yue(Qinghai Weather Modification Office,Xining Qinghai 810000,China)
出处
《青海农林科技》
2021年第2期36-42,共7页
Science and Technology of Qinghai Agriculture and Forestry
基金
青海省气象局重点项目(QXZ2020-07)。
关键词
雷达
闪电定位仪
青海省
冰雹
地闪
Radar
Lightning locator
Qinghai
Hail
Cloud-to-ground lightning
