01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-04-0227 |
| Title of Abstract | Future Plausible Changes in Surface pCO⿿ over the Bay of Bengal from Regionally Downscaled High-Resolution Models |
| Authors | B. Sridevi*, A. P. Joshi, Prasanna Kanti Ghoshal, Kunal Chakraborty |
| Organisation | Indian National Center for Ocean Information Services (INCOIS) |
| Address | Pragathinagar Hyderabad, Telangana, India Pincode: 500090 E-mail: s.bobbili-p@incois.gov.in |
| Country | India |
| Presentation | Oral |
| Abstract | The Bay of Bengal (BoB), the world⿿s largest bay in the northeastern Indian Ocean, shows marked north⿿south contrasts driven mainly by river discharge, influencing salinity, pCO2, and biological productivity. This study examines the drivers controlling seasonal pCO2 distribution in the BoB using high-resolution, regionally downscaled simulations from the Regional Ocean Modelling System (ROMS). We also examine the relative influence of pCO2 drivers in controlling its long-term variability by analyzing the northern and southern BoB separately for historical (HF; 1995⿿2014) and far-future (FF; 2080⿿2100) periods. Model results show that temperature is the dominant driver of seasonal pCO2 variability in both HF and FF. In the northern BoB, temperature contributes to a decrease in pCO2 variability during December-February (DJF) and an increase during the remaining seasons. Whereas in southern BoB, the temperature drives a decrease in pCO2 variability during DJF and June-September (JJAS) seasons, while contributing to an increase in the other seasons. Freshwater flux emerges as the dominant driver of pCO2 reduction during October⿿November (ON), particularly in the northern BoB, with contributions of ~ ⿿9 µatm in HF and ~ ⿿25 µatm in FF. The contribution of DIC is negligible in HF but becomes a significant driver (>15 µatm) in FF during DJF. Conversely, during March⿿May (MAM) in the northern BoB, the DIC contribution shifts from driving an increase (+4 µatm) in HF to a decrease (⿿8 µatm) in FF. In the southern BoB, the contribution of TA doubles in HF to FF. For long-term trends, DIC is the primary contributor to pCO2 changes, followed by temperature, in both periods. However, in FF, DIC contribution decreases by ~15% while TA contribution increases from ~ -10% to 1% in both the regions from HF to FF. This enhancement of TA alters the carbonate buffering capacity of the basin. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Bay of Bengal, pCO2, river discharge |
| For Awards | no |