01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-04-0385 |
| Title of Abstract | Changing Ocean⿿Atmosphere Interactions Governing Bay of Bengal Cyclones: A Multi-Parameter Assessment |
| Authors | Raghu Nadimpalli*, Krishna K Osuri, V. K. Soni, M. Mohapatra |
| Organisation | India Meteorological Department, New Delhi |
| Address | Urban Meteorology and Climate Cell New Delhi, New Delhi, India Pincode: 110003 E-mail: raghu.met2012@gmail.com |
| Country | India |
| Presentation | Poster |
| Abstract | The Bay of Bengal (BoB) is one of the most cyclone-prone regions, where storm development is strongly controlled by variations in atmospheric and oceanic conditions across different seasons and years. This study examines how the precursors to tropical cyclogenesis over the BoB have evolved during 1980⿿2023, using ERA5 reanalysis data along with best-track tropical cyclone records. A set of critical parameters⿿sea surface temperature (SST), vertical wind shear (200⿿850hPa), mid-level humidity (850⿿500hPa), mean sea level pressure (MSLP), and low-level vorticity (850hPa)⿿are analyzed to capture their spatial, seasonal, and temporal variability. Our analysis reveals pronounced warming of SSTs in the central and eastern BoB after 2000, accompanied by a decline in MSLP and a strengthening of cyclonic vorticity during the monsoon and post-monsoon seasons. Increasing wind shear during the monsoon appears to act as a limiting factor for cyclone growth, while mid-level humidity shows modest yet consistent reductions, particularly in the post-monsoon phase. A machine-learning-based attribution (Random Forest regression combined with partial correlations) highlights SST and low-level vorticity as the most influential predictors of seasonal cyclone frequency, followed by MSLP, with wind shear exerting seasonally dependent positive or negative impacts. Network correlations further underscore the interplay between thermodynamic and dynamical drivers of cyclogenesis. Overall, this multi-decadal assessment provides clear evidence that climate-driven shifts are altering the cyclone-conducive environment in the BoB. The findings not only have direct implications for cyclone prediction and disaster preparedness but also serve as a diagnostic framework adaptable to other cyclone basins globally. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Tropical Cyclones, Bay of Bengal, Climatology |
| For Awards | no |