中国南方地区夏季地闪和降水协同变化的特征及气象要素分析OA北大核心CSTPCD

The co-variability in the summer precipitation and cloud-to-ground lightning over South China,where climatological lighting and precipitation frequently occur(105～122 °E,20～35 °N),has been examined using the ADTD lightning location network and precipitation data merged ground-gauge,satellite,and radar.The coupling self-organizing map(SOM)has been applied to the daily flash density and precipitation anomalies from 2016 to 2021.It turns out that there are five clusters associate with the co-variability in the flash density and precipitation over South China.Specifically,the first(fifth)cluster is characterized by a dipole pattern with enhanced rainfall/increased lightning activity(suppressed rainfall/decreased lightning activity)over the Yangtze-Huai River valley and suppressed rainfall/decreased lightning activity(enhanced rainfall/increased lightning activity)over the southern part of South China.The tightest lightning-precipitation coincidence is observed in the first and fifth clusters.Results obtained from SOM exhibit large non-linearity and asymmetry of the relationship between the regional lightning and precipitation anomalies over South China.Further examinations suggest that unstable atmospheric stratifications,significant vertical differences in the atmospheric humidity,and beneficial large-scale atmospheric circulations play important roles in modulating the co-variability in the summer lightning and precipitation over South China.