Reevaluating the global and temporal distributions of lightning superbolts: insights from ENTLN data (2018-2021)

Lightning superbolts (SBs), defined as Cloud-to-Ground strikes (CGs) with extraordinarily high peak currents (Ips), represent a rare and extreme category of lightning events (< 1% of the total lightning). This study reevaluates the global and temporal distributions of SBs using data from the Earth Networks Total Lightning Network (ENTLN) collected between 2018 and 2021. By focusing on strokes with Ip ≥ 30 kA, which constitute approximately 3.25% of all recorded events, the study analyzes their spatial distribution, diel patterns, and land-ocean ratios and reevaluates the Ip cutoff for SBs. The results indicate that CGs with Ip > 30 kA are more densely concentrated over land than oceans, with continental hotspots identified in regions such as the Andes, Lake Maracaibo, the tall grass prairies of the United States and Southeast Asia. Conversely, oceanic CGs with Ip > 30 kA are relatively evenly distributed across latitudes but exhibit localized hotspots in areas such as the Mediterranean Sea, Gulf of Mexico, Maritime Indonesia and of the western coasts of Africa and Central America. The study also finds that CGs with Ip > 50 kA exhibit a sea-to-land ratio greater than one, peaking at ~ 15 for Ip > 120 kA before declining at higher Ip thresholds. Finally, temporal analyses reveal distinct diel patterns for CGs with Ips > 30,50,100 and 200 kA over land and sea, with oceanic distributions of the total lightning closely mirroring the Carnegie Curve's fair-weather atmospheric electric field diel variation.