01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-05-0308 |
| Title of Abstract | SEASONAL INHOMOGENEITY IN THE UPPER OCEAN THERMODYNAMICS OF THE BAY OF BENGAL TO INFLUENCE THE AIR-SEA INTERACTIONS |
| Authors | Moumita Dinda*, Bijan Kumar Das |
| Organisation | Department of Mathematics, Midnapore College (Autonomous) |
| Address | VILL+P.O- SHIBRAMPUR, DISTRICT-PURBA MEDINIPUR,PS-NANDIGRAM SHIBRAMPUR, West Bengal, India Pincode: 721650 E-mail: moumitadinda102@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | The air-sea interactions in the Bay of Bengal (BoB) are crucial as it produces a large number of tropical cyclones over the region. Moreover, the low-pressure systems over the BoB have a strong seasonal dominance. The complex upper ocean thermodynamics and mixing of the BoB have most significant influence on the air-sea interactions. This study analyzed the long-term (1982-2022) trend in the upper ocean thermodynamics and mixing using available observational and reanalysis data products which can potentially influence the air-sea exchange. Specifically, the analysis looked in to the upper ocean processes to control its feedback to the atmosphere during pre- and post-Indian Summer Monsoon (ISM) when the maximum tropical cyclones occur (23% and 66%, respectively). The results show that the surface as well as mixed layer temperature have an increasing trend during both pre- and post-ISM. But interestingly the subsurface temperature has a faster increasing rate in post-ISM (0.56°C) than pre-ISM (0.5°C) over the analysis period possibly owing to high (~15 m) barrier layer thickness. Although pre-ISM always has a deeper 26°C isotherm compared to post-ISM, the deepening (~10-15 m) of the 26°C isotherm from year 2001 onwards in both seasons might have a positive response on the increased tropical cyclone intensity during the same time. The ocean heat content and cyclone heat potential show faster increasing rate in post-ISM compared to pre-ISM. The outgoing heat fluxes over the BOB depict an easr-west variation in the post-ISM, while the variation is north-south in pre-ISM similar to the seasonal spatial pattern of cyclonic activities. Overall, the study provides a better understanding on the seasonal inhomogeneous behaviour of the upper ocean thermodynamic processes to influence the air-sea interactions and associated atmospheric extreme events. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Bay of Bengal, Upper ocean thermodynamics, Mixed layer, Air-sea interactions, Tropical cyclone. |
| For Awards | no |