Investigating the dynamics of intensifying tropical cyclones

Tropical cyclones (TCs) are amongst the most hazardous severe weather systems in the tropics. Forecasts of TC tracks have improved in recent years (Heming et al., 2016), enabling earlier warnings and allowing better preparations to be made. However, while forecasts of TC intensity from global numerical weather predictions (NWP) models have improved, this has been slower than for track forecasts (De Maria et al., 2014). Forecasting rapid intensification (RI) events, where maximum wind speeds increase by 30 knots in a 24-hour period (Kaplan and DeMaria, 2002), remains challenging Mesoscale processes responsible for RI are not captured by operational global NWP models. Convection-permitting regional models are able to capture these processes better but struggle to predict the timing and magnitude of RI (Short and Petch, 2018). Vortex Rossby waves (e.g., Wang et al., 2002) can be a key process for TC intensification, and large-scale equatorial waves can modify the formation and intensification of TCs too (Feng et al., 2023, Dunkerton et al., 2009). This studentship will investigate storm-scale and large-scale mechanisms for intensifying vortices and improve our understanding of the underlying processes responsible for RI.  

Fig. 1: Satellite image of Super Typhoon Rai on 06 December 2021. Image Courtesy: NASA (https://earthobservatory.nasa.gov/images/149228/super-typhoon-rai).