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Study of Sea Surface Salinity Due to River Fluxes Using the CMIP6 Models for the Bay of Bengal Region


Affiliations
1 Department of Ocean Engineering and Naval Architecture, Indian Institute of Technology, Kharagpur 721 302, India., India
 

The large influx of freshwater and mixing of different water masses make simulating salinity challenging for the Bay of Bengal (BoB) region. This study analyses the variability of the simulated sea surface salinity (SSS) using models present in the Coupled Modal Intercomparison Project Phase 6 (CMIP6). We collected data for 37 models from CMIP6 and validated them against the Argo (2005–14) and Aquarius (2011–14) data. Based on the skill scores, we narrowed down our search to one CMIP6 model, viz. CIESM. This model was used to study the freshwater spread (FWS) in BoB during different seasons. We found that the correlation between pH and FWS was appreciable. The CIESM model was then used to project the future trends for 10 years for the tier-1 scenario. The trend analysis of future projections revealed a positive trend in SSP1-2.6, with a decrea­sing trend in SSP2-4.5 and SSP5-8.5.

Keywords

Climate Models, Freshwater Spread, River Fluxes, Skill Score, Trend Analysis.
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  • Study of Sea Surface Salinity Due to River Fluxes Using the CMIP6 Models for the Bay of Bengal Region

Abstract Views: 196  |  PDF Views: 129

Authors

V. Kumar
Department of Ocean Engineering and Naval Architecture, Indian Institute of Technology, Kharagpur 721 302, India., India
A. P. Joshi
Department of Ocean Engineering and Naval Architecture, Indian Institute of Technology, Kharagpur 721 302, India., India
H. V. Warrior
Department of Ocean Engineering and Naval Architecture, Indian Institute of Technology, Kharagpur 721 302, India., India

Abstract


The large influx of freshwater and mixing of different water masses make simulating salinity challenging for the Bay of Bengal (BoB) region. This study analyses the variability of the simulated sea surface salinity (SSS) using models present in the Coupled Modal Intercomparison Project Phase 6 (CMIP6). We collected data for 37 models from CMIP6 and validated them against the Argo (2005–14) and Aquarius (2011–14) data. Based on the skill scores, we narrowed down our search to one CMIP6 model, viz. CIESM. This model was used to study the freshwater spread (FWS) in BoB during different seasons. We found that the correlation between pH and FWS was appreciable. The CIESM model was then used to project the future trends for 10 years for the tier-1 scenario. The trend analysis of future projections revealed a positive trend in SSP1-2.6, with a decrea­sing trend in SSP2-4.5 and SSP5-8.5.

Keywords


Climate Models, Freshwater Spread, River Fluxes, Skill Score, Trend Analysis.

References





DOI: https://doi.org/10.18520/cs%2Fv124%2Fi11%2F1290-1299