01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-04-0213 |
| Title of Abstract | Indian Ocean Acidification Under Future Climate Scenarios: Bias-Corrected CMIP6 Model Projections |
| Authors | Athira K*, A. P. Joshi, Prasanna Kanti Ghoshal, B. Sridevi, Linta Rose, Kunal Chakraborty |
| Organisation | Kerala University of Fisheries and Ocean Studies, Kochi |
| Address | kundanath veluthedath, Peringannur, Palakkad, Kerala Peringannur, Kerala, India Pincode: 679535 E-mail: kathira083@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | This study examines projected changes in the Indian Ocean (IO) acidification using bias-corrected surface pH simulations from Coupled Model Intercomparison Project Phase 6 (CMIP6) outputs. Surface pH datasets from three CMIP6 models were bias-corrected using two observation-based reconstructed datasets, CMEMS-LSCE-FFNN and OceanSODA. The resulting bias-corrected multi-model ensemble dataset, which we name BEM_pH (1985-2100), showed a significant reduction in bias by about 84% ± 8% during the historical period (1985-2014). The June to September season (JJAS) of the historical period shows the lowest pH values (<8.05) over the western Arabian Sea (AS) and the highest pH values (>8.1) over the southern IO. The bias-corrected future projections indicate a continuous decline in the IO surface pH (increase in [H+]) across all scenarios, with estimated relative change of 2.13% ± 0.11% (60.61% ± 4.06%) for SSP5-8.5, 1.43% ± 0.07% (31.24% ± 1.91%) for SSP2-4.5, and 0.93% ± 0.045% (18.95% ± 1.05%) for SSP1-2.6. During the historical and future periods under the SSP5-8.5 and SSP2-4.5, the southern IO and the eastern Bay of Bengal (BoB) regions exhibit the highest decline (rise) in pH ([H+]). The analysed seasonal amplification between the far-future (2071-2100) and the historical periods is most pronounced in the BoB (143.24%) and the southern IO region (121.05%) under high-emission scenarios. We further observe a prolonged seasonal extreme ocean acidification over the AS and central IO in the far-future period, which may pose a serious risk to marine ecosystems, biodiversity, and regional fisheries. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Indian Ocean, pH, CMIP6, Uncertainty, Ocean acidification |
| For Awards | yes |
| Date Of Birth | 07-02-1998 |
| ECSN Registration Number | IIOE2-ECSN-0149 |