Abstract
The objective of the paper is to use the data collected along two meridional sections (45° E and 57°30′ E) during the austral summer (January–March) 2004 to understand the influence of seabed topography across the Madagascar and Southwest Indian Ridges on hydrographic parameters. The study was supplemented by World Ocean Circulation Experiment (WOCE) Conductivity-Temperature-Depth data collected during February–March 1996 along 30° E, as well as Levitus climatology. A southward shift of 2° latitude (between 45° E and 57°30′ E) was recorded for the two predominant frontal structures, i.e., the Agulhas Return Front and Southern Subtropical Front, which is attributed to the influence of seabed topography on hydrographic parameters. No significant spatial variation of these fronts was noted between the 30° E and 45° E meridional sections. Between latitudes 31° S and 42° S, the temperature and salinity structures show deepening over the ridges. The Antarctic Circumpolar Current core was detected between 40°15′ S and 43° S.
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Acknowledgements
We are grateful to the Ministry of Earth Sciences, Govt. of India for the financial support and the Director, NCAOR for his encouragement to pursue these studies and publish. We acknowledge Drs. V. S. N. Murty, V. Ramesh Babu and Y. K. Somayajalu of NIO, Goa for their suggestions on the draft manuscript and support extended in CTD data processing. All participants of SO cruise are acknowledged for their onboard cooperation and help rendered in the execution of this project.
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Anilkumar, N., Pednekar, S.M. & Sudhakar, M. Influence of ridges on hydrographic parameters in the Southwest Indian Ocean. Mar Geophys Res 28, 191–199 (2007). https://doi.org/10.1007/s11001-007-9026-5
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DOI: https://doi.org/10.1007/s11001-007-9026-5