湖南雷暴天气中地闪活动的预报研究

Forecasting of CG Lightning Activity in Thunderstorms in Hunan

利用湖南地区ADTD闪电定位仪资料,结合NCEP/NCAR再分析资料,对湖南夏季雷暴发生过程中地闪的区域特征、及地闪与大气不稳定参数的相关关系进行分析,提出地闪活动预报的诊断指标并建立不同区域地闪数的预报方程。结果表明:采用经验正交方法研究地闪活动的空间分布特征发现湖南地闪活动可分为3个区域:湘西山地区、湘东北平原区及湘南山地区,各区与地闪相关性好的不稳定参数分别为,湘西山地区:对流不稳定能量、抬升指数、修正K指数及粗理查逊数;湘东北平原区:抬升指数、修正K指数及大气可降水量;湘南山地区:通气管指数。并且不稳定参数与地闪数具有一定的回归关系,各区潜势预报方程对实际应用具有参考价值。

Bases on the data of ADTD lightning location system and NCEP/NCAR reanalysis, the characteristics of CG lightning activity in thunderstorms over Hunan in summer and the relationship between atmospheric instability parameter and CG lightning activity are analyzed in this paper. The results show as follows： by using the EOF analy- sis method, the CG lightning activity on field can be clustered to 3 regions： western mountainous region of Human, southern mountainous region of Hunan, northeastern plain region of Hunan. In western mountainous region of Hu- man, the correlations between the CAPE, LI, MK, BRN and CG lightning activity are better than others. In north- eastern plain region of Htman, the correlations between the LI, MK, PW and CG lightning activity are better than others. In southern mountainous region of Hunan, the correlation between the CI and CG lightning activity is better than others. In addition, the linear regression relation between lightning and these parameters are analyzed. The po- tential predictability functions in each region can provide the reference for lightning in practical application.