Journal of the Oceanographical Society of Japan

, Volume 32, Issue 6, pp 284–296 | Cite as

Water characteristics and current structure at 65°E during the southwest monsoon

  • G. S. Sharma


Hydrographic data collected aboard R. V. Anton Bruun along 65°E between 18°N and 42°S from 17 May to 4 July 1964 are used to investigate water characteristics and current structure in the upper 500 m in the Indian Ocean. The water characteristics indicate the occurrence of three main water masses,viz., warm, saltier, low-oxyty and nutrient-rich Arabian Sea Surface Water, relatively fresh and high-oxyty Equatorial Indian Ocean Water, and more saline, high-oxyty and nutrient-poor Tropical Water of the South Indian Ocean. The recently discovered South Equatorial Countercurrent and Subtropical Countercurrent (renamed Tropical Countercurrent, at the suggestion of Dr. R. B.Montgomery) are observed in the current structure at 13°S and 22°–26°S respectively, and these could also be identified on the vertical sections of temperature, thermosteric anomaly and salinity. Contrary to the existing concept, the North Equatorial Current continues to be present even after the onset of the southwest monsoon. The Equatorial Undercurrent could not be traced in the Indian Ocean during this period.


Indian Ocean Vertical Section Southwest Monsoon Equatorial Indian Ocean Current Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Oceanographical Society of Japan 1976

Authors and Affiliations

  • G. S. Sharma
    • 1
  1. 1.Central Marine Fisheries Research InstituteCochin, KeralaIndia

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