01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-05-0373 |
| Title of Abstract | Some characteristics of rapidly intensifying tropical cyclones over the North Indian Ocean |
| Authors | Monica Sharma*, Mrutyunjay Mohapatra, Suneetha P, PLN Murty |
| Organisation | India Meteorological Department, New Delhi-110003 |
| Address | DGM office, IMD New Delhi, DELHI, India Pincode: 110003 E-mail: moniimd@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | A tropical cyclone (TC) is a devastating coastal hazard developing over the north Indian Ocean (NIO) causing loss of lives & properties and affecting the ecosystem. Hence, it is very essential to accurately monitor and predict the genesis, track, intensity, landfall processes and adverse weather associated with TCs impacting the NIO, coastal states and the shoreline eco-system. Though, there has been significant improvement in prediction of track, intensity and landfall processes leading to 40-50% improvement in forecast accuracy in recent decade, still predicting intensity, especially the rapid intensification (RI) is a challenge. Over the North Atlantic Ocean, the RI has been defined as the change in intensity by at least 30 kt in 24 hours period and it corresponds to 95th percentile. Currently, over the NIO also same formula is used. Thus, a study has been undertaken to find out the salient characteristics of RI of TCs over the NIO based on the best track data of IMD over the period of 35 years (1990-2024). Study shows that over the NIO, 30 kt RI corresponds to 90th percentile, indicating that RI is more frequent over the NIO compared to North Atlantic Ocean. All such cases satisfying the 90th percentile of intensity change are analysed further to find out associated dynamic and thermodynamic features. Most of the extremely severe TCs (maximum sustained wind speed 90 kt) show RI over the NIO. Results indicate that RI over NIO is associated with deep convection triggered by low level relative vorticity & convergence, upper-level divergence supported by anticyclonic flow and thus low vertical wind shear of horizontal wind, higher ocean heat content based on ERA5 and CIMSS products analysis. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Rapid intensification, tropical cyclones, North Indian Ocean |
| For Awards | no |