On the Possible Mechanisms for Saltening of the Bay of Bengal

Anoopa Prasad C; P.V. Hareesh Kumar

doi:10.14429/dsj.69.12220

Anoopa Prasad C DRDO-Naval Physical and Oceanographic Laboratory, Kochi – 682 021, India
P.V. Hareesh Kumar DRDO-Naval Physical and Oceanographic Laboratory, Kochi – 682 021, India

DOI: https://doi.org/10.14429/dsj.69.12220

Keywords: Bay of Bengal, Salt water pumping, Eddies, Upwelling, Cyclone

Abstract

The Bay of Bengal (BoB) is a low saline basin owing to large influx of freshwater from precipitation and river runoff. To maintain the salt balance of the BoB, the incessant lowering of salinity is to be balanced by the inflow of saltier water into the basin. In the present work, various processes that contribute to the saltening of the BoB, viz. coastal upwelling, eddies and their interaction, lateral advection from Arabian Sea and tropical cyclones are discussed. In the near-shore regions, the coastal upwelling due to wind induced Ekman transport plays a dominant role in increasing the surface salinity. On the other hand, in the open ocean, the divergence induced by eddies and their mutual interaction contributes significantly to the salt water pumping. In the southern BoB, the advection from the Arabian Sea increases the salinity. The formation of cyclones in the BoB also leads to an increase in the surface salinity. However, the magnitude of saltening of the Bay due to these processes varies from north to south. The uplift of saltier water from subsurface levels increases the salinity in the surface layers thereby creating a salinity gradient and a salinity front.

Author Biographies

Anoopa Prasad C, DRDO-Naval Physical and Oceanographic Laboratory, Kochi – 682 021, India

Ms C. Anoopa Prasad completed her MSc (Oceanography) from Cochin university of Science and Technology (CuSAT) and submitted her PhD thesis under the Faculty of Marine Sciences, CUSAT. Presently working as Project Scientist at National Institute of Ocean Technology, Chennai.
In the current study, she helped in formulation of concept and research objectives, programming and supporting algorithms, preparation of figures, writing - original draft preparation, critically reviewing the manuscript.

P.V. Hareesh Kumar, DRDO-Naval Physical and Oceanographic Laboratory, Kochi – 682 021, India

Dr P.V. Hareesh Kumar obtained his MSc (Oceanography) and PhD (Oceanography) from Cochin university of Science and Technology (CUSAT). He is the Associate Director and Scientist ‘G’ at DRDO-Naval Physical and Oceanographic Laboratory, Kochi. His field of specialisation include: Air-sea interaction, Mixed layer dynamics, Thermohaline variability, Ocean modelling, ASW Oceanography.
In the current study, he helped in formulation of concept and research objectives, overseeing the research activity, planning and execution, writing - original draft preparation, critically reviewing the manuscript.

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