福建对流体霰粒子层厚度特征与地闪初生关系研究OA

Based on the dual-polarization radar particle classification products and cloud-to-ground lightning location data from Fuzhou,Xiamen and Longyan from April 2022 to June 2024,in this study we select 54 convective storm samples with or without cloud-to-ground lightning and investigate the temporal variation characteristics of graupel particle layer thickness during the developing processes of these samples.The re-sults show that the graupel particle layer thickness of convective storms with cloud-to-ground lightning reaches at least 2.26 km at the initiation moment of the first cloud-to-ground lightning,while 95％of the samples without cloud-to-ground lightning,have graupel particle layer thickness less than 2.2 km through-out their lifecycles.Considering both the lead time and accuracy of cloud-to-ground lightning initiation forecasts,we propose to use a graupel particle layer thickness greater than 2 km as a forecast indicator for cloud-to-ground lightning initiation in Fujian Province.The forecast potential is evaluated,and the calcu-lated TS score of the sample is 0.864 and the average forecast lead time is 28.13 min.Taking four convec-tive storms on 14 June 2022 in southern Fujian Province as examples,the above-mentioned forecast indica-tors are applied and analyzed in these cases.The results show that the proposed forecast indicator can ac-curately forecast whether cloud-to-ground lightning will occur in the four convective storms,and the fore-cast lead time for cloud-to-ground lightning initiation is 6 min.