Oceanographic features of the Indian Ocean sector of Coastal Antarctica (Short Communication)
Vol.10,No.1(2020)
A review is presented on physical oceanographic features based on expendable CTD data collected in the Indian Ocean sector of the Southern Ocean. The thermohaline structure is dominated by Circumpolar Deep Water. The temperature and salinity are affected by cyclonic circulation in the Weddell Sea and Prydz Bay. High chlorophyll-a blooms (2-4 mg m-3) evolve during austral summer due to stratification which is caused by freshwater generated from the sea ice melt and the glacial outflow which traps phytoplankton in a shallow mixed layer, where they are exposed to higher irradiances of photosynthetically active radiation. Attempts have been made to relate the physical characteristics to biomass inferred from data published from previous Indian Scientific expeditions. More in-situ observations related to biophysical and chemical are recommended in the near future projects.
Indian Ocean sector; oceanography; water masses; circulation; hydrography; chlorophyll-a
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