A study of ocean parameters in Bay of Bengal (BoB) using indigenised drifting buoys
Drifting buoys (DBs) are widely deployed to observe near-surface ocean currents and sea surface temperature. The National Institute of Ocean Technology (NIOT), Chennai, India, had indigenised the DB with the Indian satellite (INSAT) in 2012. This paper describes the results of various studies conducted by NIOT using the indigenised DBs and also describes unique features attempted in indigenised DBs to measure the near-surface ocean current with 24 position acquisitions per day to capture small-scale surface eddies and the use of real-time geostationary satellite communication every hour. Additionally, the surface currents observed with indigenous DB are compared with DBs available in the market, Marlin-Yug (coefficient of determination R2 > 0.88) and forecast using the ocean surface current analyses real-time (coefficient of determination R2 > 0.90). Our results show that the DBs in the Bay of Bengal are carried with the East India Coastal Current in the March–May periods and the in-situ observations by the DB provide accurate surface current observations than satellite-based data. Furthermore, the new observations near the world’s largest tidal mangrove and delta system, the Sundarbans and Bengal Delta, will help in further enhancing our understanding of the spatiotemporal variability in the region in terms of coastal currents and its influence on marine environments.
KeywordsDrifting buoy surface current EICC INSAT GPS eddies
The authors gratefully thank all the staff members of National Institute of Ocean Technology and heartfelt thanks to director, NIOT for his vital and continuous encouragement and support extended during this developmental work. The development and deployment are fully funded by MoES (Ministry of Earth Sciences, Govt. of India). The authors are also thankful to vessel management cell, NIOT for allocated vessel time for DB deployment operations.
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