• Login
    View Item 
    •   DSpace Home
    • Institute's contributions
    • Scholarly literature
    • View Item
    •   DSpace Home
    • Institute's contributions
    • Scholarly literature
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Eddy-mediated biological productivity in the Bay of Bengal during fall and spring intermonsoons

    Thumbnail
    View/Open
    Deep_Sea_Res_Pt_I_54_1619.pdf (2.208Mb)
    Date
    2007
    Author
    PrasannaKumar, S.
    Nuncio, M.
    Ramaiah, N.
    Sardesai, S.
    Narvekar, J.
    Fernandes, V.
    Paul, J.T.
    Metadata
    Show full item record
    Abstract
    The signature of cold-core eddies and their role in altering the biological productivity of the Bay of Bengal was examined using two recent sets of hydrographic data collected along the central and western Bay of Bengal during fall (14 September – 12 October, 2002) and spring (12 April – 7 May, 2003) intermonsoons under the Bay of Bengal Process Studies (BOBPS) programme. Based on the thermohaline structure and the satellite-derived sea-level anomaly maps 9 cyclonic eddies were identified. Out of this, 4 cyclonic eddies – 2 each along the central Bay and along the western boundary – occurred during fall intermonsoon 2002, while 5 occurred – 3 along the central Bay and 2 along the western boundary – during spring intermonsoon. The eddy depressed the temperature, which varied from 3oC to 7oC at 120 m depth. Maximum depression of temperature was associated with spring-time eddies in the northern Bay, where subsurface stability was low. The reduced water column stability in spring leads to greater eddy-pumping, thereby cooling the water to a greater extent. However, the cyclonic eddies were unable to break the stratification of the top 20m layer, thereby curtailing their effects below this depth during both seasons. Eddy-pumping not only cooled the water column but also enhanced the nutrient concentrations. This in turn increased the biological productivity of the Bay to 1½-2 times. In addition, the subsurface chlorophyll maximum (SCM), which is generally located between 40 and 70 m in fall and 60 and 90 m in spring intermonsoons, shallowed under the influence of the eddies and also enhanced the chlorophyll concentration in the SCM to more than double. Thus, eddy-pumping of nutrients controls the biological productivity of the Bay of Bengal during both the seasons. In the fall intermonsoon, however, the riverine input of nutrients and sediments in the northern Bay also plays a role in altering the biological productivity. This has an overall implication to the basin-wide new production and export flux and, at least partly, resolves the reason for the comparable annual fluxes of organic carbon between the high-productivity Arabian Sea and low-productivity Bay of Bengal.
    URI
    http://drs.nio.org/drs/handle/2264/652
    Collections
    • Scholarly literature [9074]

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV
     

     

    Browse

    All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister

    DSpace software copyright © 2002-2016  DuraSpace
    Contact Us | Send Feedback
    Theme by 
    Atmire NV