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

Author: Md. Masud-Ul-Alam, Sirajuddin Md. Babar Chowdhury, Md. Rashed-Un- Nabi, Md. Wahidul Alam, Md. Ashif Imam Khan, Kashafad Bin Hafiz
DOI: doi.org/10.70279/bmj-v4-i1-1009
Click here to view citation data

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.

Item Value
Serial 1
Article PDF Download
Total Citation Click here to view citation data
How to Cite
Article Page Views 1468
Article Downloads 6
Article Volume Volume 04
Article Issue Issue 1
Article DOI doi.org/10.70279/bmj-v4-i1-1009
Article Conference Acronym
Manuscript Number
Status Show
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
Article References

Arun Kumar, S. V.V., K. N. Babu, and A. K. Shukla. 2015. “Comparative Analysis of Chlorophyll-a Distribution from SeaWiFS, MODIS-Aqua, MODIS-Terra and MERIS in the
Arabian Sea.” Marine Geodesy 38 (1): 40–57. https://doi.org/10.1080/01490419.2014.9149 90. 
Babu, M. T., Y. V.B. Sarma, V. S.N. Murty, and P. Vethamony. 2003. “On the Circulation in the Bay of Bengal during Northern Spring Inter-Monsoon (March-April 1987).” Deep-Sea Research Part II: Topical Studies in Oceanography 50 (5): 855–65. https://doi.org/10.1016/S0967-0645(02)00609-4.
Balachandran, K K, C M Laluraj, R Jyothibabu, N V Madhu, K R Muraleedharan, John Gerson Vijay, P A Maheswaran, T T Mohammed Ashraff, K K C Nair, and C T Achuthankutty. 2008. “Hydrography and Biogeochemistry of the North Western Bay of Bengal and the North Eastern Arabian Sea during Winter Monsoon.” Journal of Marine Systems 73 (1–2): 76–86.
Chowdhury, K M Azam, Abu Sharif Md Mahbub-E-Kibria, Shaila Akhter, Nuruddin Md Khaled Chowdhury, and Md Marufujjaman. 2017. “Variation of Water Column Density in the Bay of Bengal Aquatic Ecosystem.” 

Gauns, Mangesh, M. Madhupratap, N. Ramaiah, R. Jyothibabu, Veronica Fernandes, Jane T. Paul, and S. Prasanna Kumar. 2005. “Comparative Accounts of Biological Productivity Characteristics and Estimates of Carbon Fluxes in the Arabian Sea and the Bay of Bengal.”
In Deep-Sea Research Part II: Topical Studies in Oceanography, 52:2003–17. https://doi.org/10.1016/j.dsr2.2005.05.009.
Hussain, Mohammad, Yoshimitsu Tajima, Mohammed Hossain, and Partho Das. 2017. “Impact of Cyclone Track Features and Tidal Phase Shift upon Surge Characteristics in the Bay of Bengal along the Bangladesh Coast.” Journal of Marine Science and Engineering 5 (4): 52. https://doi.org/10.3390/jmse5040052.
Jyothibabu, R, C R Asha Devi, N V Madhu, P Sabu, K V Jayalakshmy, Josia Jacob, H Habeebrehman, M P Prabhakaran, T Balasubramanian, and K K C Nair. 2008. “The Response of Microzooplankton (20--200 $μ$m) to Coastal Upwelling and Summer Stratification in the Southeastern Arabian Sea.” Continental Shelf Research 28 (4–5): 653–71.
Jyothibabu, R, N V Madhu, K V Jayalakshmi, K K Balachandran, C A Shiyas, G D Martin, and K K C Nair. 2006. “Impact of Freshwater Influx on Microzooplankton Mediated Food Web in a Tropical Estuary (Cochin Backwaters--India).” Estuarine, Coastal and Shelf Science 69 (3–4): 505–18.
Longhurst, Alan R. 2007. Ecological Geography of the Sea. Ecological Geography of the Sea. Elsevier Inc. https://doi.org/10.1016/B978-0-12-455521-1.X5000-1.
Murty, V. S.N., Y. V.B. Sarma, D. P. Rao, and C. S. Murty. 1992. “Water Characteristics, Mixing and Circulation in the Bay of Bengal during Southwest Monsoon.” Journal of Marine Research 50 (2): 207–28. https://doi.org/10.1357/002224092784797700.
Prasanna Kumar, S, P M Muraleedharan, T G Prasad, M Gauns, N Ramaiah, S N De Souza, S Sardesai, and M Madhupratap. 2002. “Why Is the Bay of Bengal Less Productive during Summer Monsoon Compared to the Arabian Sea?” Geophysical Research Letters 29 (24):81–88.

Rajamani, V, U C Mohanty, R Ramesh, G S Bhat, P N Vinayachandran, D Sengupta, S Prasanna Kumar, and R K Kolli. 2006. “Linking Indian Rivers vs Bay of Bengal Monsoon
Activity.” In. Ramage, Colin S. 1971. “Monsoon Meteorology.”
Shetye, S. R., S. S.C. Shenoi, A. D. Gouveia, G. S. Michael, D. Sundar, and G. Nampoothiri. 1991. “Wind-Driven Coastal Upwelling along the Western Boundary of the Bay of Bengal during the Southwest Monsoon.” Continental Shelf Research 11 (11): 1397–1408. https://doi. org/10.1016/0278-4343(91)90042-5.
Subramanian, V. 1993. “Sediment Load of Indian Rivers.” Current Science, 928–30. Vinayachandran, P. N., V. S. N. Murty, and V. Ramesh Babu. 2002. “Observations of Barrier Layer Formation in the Bay of Bengal during Summer Monsoon.” Journal of Geophysical Research: Oceans 107 (C12): SRF 19-1-SRF 19-9. https://doi.org/10.1029/2001JC000831.
Share With: