Spatiotemporal variability of bomb cyclones over the Black Sea Basin
摘要
Mid-latitude cyclones are synoptic-scale systems that play a key role in the transport of energy and momentum within the atmospheric circulation and are often associated with severe weather. Among these systems, explosive cyclones (bomb cyclones) are characterized by rapid deepening over a short period and can produce strong winds, heavy precipitation, and hazardous marine conditions. Although bomb cyclones primarily occur over open oceans, they may also develop over semi-enclosed basins such as the Black Sea under favorable atmospheric conditions. Because of its geographical location, land–sea thermal contrasts, and complex topography, the Black Sea Basin provides a conducive to rapid cyclogenesis. This study examines the spatiotemporal variability of bomb cyclones over the Black Sea Basin using ERA5 reanalysis for covering the 1995–2024 period. Cyclone centers were identified and tracked using a Lagrangian approach, and 24-hour central pressure changes were calculated. Bomb cyclones were defined using the latitude-normalized deepening rate (NDRc), and systems with NDRc ≥ 1.0 were included in the analysis. The identified events were evaluated in terms of their seasonal occurrence, minimum central pressure, deepening rate, duration, translation speed, and track patterns. The analysis identified 10 bomb cyclone events over the Black Sea Basin during the study period. All events occured between November and March, and none were observed during summer. Minimum central pressures ranged from 970 to 990 hPa, and the mean pressure drop was about 29 hPa. These results indicate that although bomb cyclones are rare in the Black Sea Basin, but they can still produce substantial meteorological impacts when the atmospheric setting is favorable.