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Observed Variability of Surface Layer in the Central Bay of Bengal:Results of Measurements Using Glider


Affiliations
1 National Institute of Ocean Technology, Ministry of Earth Sciences, Pallikaranai, Chennai 600 100, India
2 College of Engineering, Guindy Campus, Anna University, Chennai 600 025, India
 

Underwater gliders measure high-resolution spatiotemporal oceanographic data. In April 2014, the National Institute of Ocean Technology, Chennai operated an underwater glider ‘Barathi’, for 127 days for observation of Bay of Bengal (BoB). In this article we present the effectiveness of the glider Barathi for high resolution temporal sampling of the surface layer in the central BoB for studying variation of temperature, salinity and density structures and acoustic characteristics on 26–27 May 2014. The results showed ‘afternoon effect’ on acoustic characteristics and formation of secondary sound channel. Our data set is strongly correlated (coefficient of determination r2 > 0.96) with data from a nearby Array for real-time geostrophic Oceanography (Argo) float.

Keywords

Bay of Bengal, Density, Eddy, Glider, Salinity, SLD, MLD, Ocean Observation, Temperature.
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  • Observed Variability of Surface Layer in the Central Bay of Bengal:Results of Measurements Using Glider

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Authors

Shijo Zacharia
National Institute of Ocean Technology, Ministry of Earth Sciences, Pallikaranai, Chennai 600 100, India
R. Seshasayanan
College of Engineering, Guindy Campus, Anna University, Chennai 600 025, India
Tata Sudhakar
National Institute of Ocean Technology, Ministry of Earth Sciences, Pallikaranai, Chennai 600 100, India
M. A. Atmanand
National Institute of Ocean Technology, Ministry of Earth Sciences, Pallikaranai, Chennai 600 100, India
R. R. Rao
National Institute of Ocean Technology, Ministry of Earth Sciences, Pallikaranai, Chennai 600 100, India

Abstract


Underwater gliders measure high-resolution spatiotemporal oceanographic data. In April 2014, the National Institute of Ocean Technology, Chennai operated an underwater glider ‘Barathi’, for 127 days for observation of Bay of Bengal (BoB). In this article we present the effectiveness of the glider Barathi for high resolution temporal sampling of the surface layer in the central BoB for studying variation of temperature, salinity and density structures and acoustic characteristics on 26–27 May 2014. The results showed ‘afternoon effect’ on acoustic characteristics and formation of secondary sound channel. Our data set is strongly correlated (coefficient of determination r2 > 0.96) with data from a nearby Array for real-time geostrophic Oceanography (Argo) float.

Keywords


Bay of Bengal, Density, Eddy, Glider, Salinity, SLD, MLD, Ocean Observation, Temperature.

References





DOI: https://doi.org/10.18520/cs%2Fv113%2Fi11%2F2151-2159