01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-06-0288 |
| Title of Abstract | Signatures of Diffusive Convection Associated with Thermal Inversion in the Barrier Layer of the North Indian Ocean |
| Authors | Girishkumar M S, Ashin K*, Pavan Kumar Jonnakuti |
| Organisation | Indian National Centre for Ocean Information Services |
| Address | Indian National Centre for Ocean Information Services Hyderabd, Telengana, India Pincode: 500090 E-mail: a.kuriakose-p@incois.gov.in |
| Country | India |
| Presentation | Oral |
| Abstract | Diffusive convection (DC), a form of double-diffusive mixing, plays an important role in regulating vertical fluxes of heat, salt, and dissolved properties in the ocean. The barrier layer (BL), situated between the base of the mixed layer and the top of the isothermal layer, is generally characterized by weak shear-driven mixing. To investigate signatures of DC associated with thermal inversions within the BL, we developed a global climatology using Argo and eXpendable Conductivity⿿Temperature⿿Depth (XCTD) observations. The analysis identifies the northern Bay of Bengal (BoB) and the southeastern Arabian Sea (SEAS) as prominent hotspots during winter, where strong salinity stratification supports thermal inversions and establishes conditions favorable for DC. Microstructure measurements from two research cruises, collected in this region using the Vertical Microstructure Profiler (VMP-250), further confirm the presence of DC-favorable stratification, with low shear-driven mixing reflected in eddy diffusivity values on the order of 10⁻⁵ m² s⁻¹. We also quantified the relative importance of DC on the mixed-layer heat budget during the peak phase of DC activity in the BL. These results demonstrate that DC contributes significantly to sea surface temperature (SST) variability in the BoB and SEAS during winter. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Diapycnal mixing, Ocean turbulence, Mixed layer |
| For Awards | yes |
| Date Of Birth | 19-09-1995 |
| ECSN Registration Number | IIOE2-ECSN-0165 |