Seasonality of Stratification Along the Offshore Area of the Northern Bay of Bengal

Md. Masud-Ul-Alam-|||-Department of Oceanography and Hydrography, Bangabandhu Sheikh Mujibur Rahman Maritime University, Bangladesh===|===Sirajuddin Md. Babar Chowdhury-|||-Department of Oceanography, University of Chittagong, Bangladesh===|===Md. Rashed-Un- Nabi-|||-Department of Fisheries, University of Chittagong, Bangladesh===|===Md. Wahidul Alam-|||-Institute of Marine Science, University of Chittagong, Bangladesh===|===Md. Ashif Imam Khan-|||-Department of Oceanography and Hydrography, Bangabandhu Sheikh Mujibur Rahman Maritime University, Bangladesh===|===Kashafad Bin Hafiz-|||-Department of Oceanography and Hydrography, Bangabandhu Sheikh Mujibur Rahman Maritime University, Bangladesh
2022-08-26
Item Value
Serial 1
Article Conference Acronym
Manuscript Number
Article Volume Volume 04
Article Issue Issue 1
Article DOI doi.org/10.70279/bmj-v4-i1-1009
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Article Slug seasonality-of-stratification-along-the-offshore-area-of-the-northern-bay-of-bengal
Article Keyword Stratification, sigma-t, Argo, Stability Parameter, Northern Bay of Bengal
Article Entry Time 16:06:20
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Article References

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Abstract

One of the vital factors for understanding and investigating ocean dynamics is the stratification of the water column. Argo profiling floats for the period of January 2011 to September 2017 and World Ocean Data (WOD) for the same region were taken to comprehensively study temperature-salinity distribution from which to calculate the sigma-t (density). The average density increased sharply from around 20 m to 180 m depth. It is obvious that the northern Bay of Bengal (BoB) is much cooler than the southern bay. Additionally, the southern BoB is denser than the northern BoB. The strong seasonal cycle of temperature and salinity was noticed which eventually controls the comparatively fresher water in the north and saltier water to the south. Furthermore, the static stability parameter of the water column was used to understand the processes affecting the stratification. The more the water is stable, the more the stratification of water is observed. Vertical stability was undulated in the upper 200 m and between 300-500 m depth. It was also found to be varied with strong south-west monsoon and north-east monsoon. Summer monsoon showed much stable than the winter monsoon because of the river runoff. Perhaps, the less dense water floating in the surface in summer could create the layer much stratified by inhibiting the subsurface nutrient to come upward and the opposite pattern was seen in winter monsoon. In spring and fall, southern BoB stability was stronger than northern. The study revealed that both of the available open-source datasets are very useful and precise to each other.