7TROPICAL Global Trends in Duration and Volume of Rapid Intensification Events

Rapid intensification (RI) of tropical cyclones (TCs) remains one of the major challenges in hurricane modeling and forecasting. Several studies have been conducted by the scientific community to find the potential connections between the RI events and a warming climate, suggesting an overall increase in their frequency (Klotzbach et al. 2022, Bhatia et al. 2022, Manikanta et al. 2023, Li et al. 2023). In this study, the concept of rapid intensification volume (RIV) is introduced to quantify the combined effects of duration and intensification magnitude. For the duration component of the RIV analysis, we adopted the definitions of RI event and RI case suggested by Tao et al. (2017) and Kieper and Jiang (2012), as well as their approach to characterize the life cycle of the entire RI event, including the phases before, during and ending.

The trends of RI events are presented in light of their RIV for single and multiple occurrences across all global basins and all TC categories (including TDs) through the analysis of 40 years of best-track data(1982-2022). Preliminary results show that RIV is slightly increasing globally, with more statistical significance when multiple RI occurrences are considered. Regarding basin activity, RIV is more pronounced in the North Atlantic and South Indian Ocean. Further analysis of the RIV components suggests that the increasing trend is more attributed to intensification gradients than variation in the RI duration.