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Abstract:
In this study, based on the cloud-top height (CTH) data and lightning detector (LMI) data acquired by the AGRI detector on board the FY-4A geostationary satellite, the LMI data were processed using the cluster analysis method, and the cloud-top height data of thunderstorms were quality controlled based on CALIPSO data. Convective systems in different regions over land and adjacent seas in China were identified, datasets of thunderstorms and penetrating convection were obtained, and the characteristics of cloud-top height and lightning activity of thunderstorms (TS) and overshooting convection (OC) and their relationships were analyzed. The results show that the ratio of the number of OCs to the number of TSs is 12.3% on average in different regions on land, while the ratio is 24.85% in oceanic regions, indicating that thunderstorms in the ocean are more likely to evolve into penetrating convection; most thunderstorms with CAPE1/2 and CTH are mainly concentrated in the regions with 15 ms-1 < CAPE1/2 < 50 ms-1 and 11 km < CTH < 17.5 km. region, and most of the updraft velocities and CTHs in OC were mainly concentrated in the region of 20 ms-1 < CAPE1/2 < 50 ms-1 and 15 km < CTH < 19 km. For both thunderstorms and overshooting convection, lower updrafts produce lower lightning rates (characterization by flash extent density, FED) and larger lightning horizontal scales (characterization by minimum flash area, MFA); conversely, larger updrafts produce higher lightning rates and smaller lightning horizontal scales.
