Ocean Science Journal

, Volume 43, Issue 3, pp 147–152 | Cite as

Seasonal variability of sonic layer depth in the Central Arabian Sea

  • TVS Udaya Bhaskar
  • Debadatta Swain
  • M Ravichandran


The seasonal variability of sonic layer depth (SLD) in the central Arabian Sea (CAS) (0 to 25°N and 62-66°E) was studied using the temperature and salinity (T/S) profiles from Argo floats for the years 2002–2006. The atmospheric forcing responsible for the observed changes was explored using the meteorological data from NCEP/NCAR and Quickscat winds. SLD was obtained from sound velocity profiles computed from T/S data. Net heat flux and wind forcing regulated SLD in the CAS. Up-welling and down-welling (Ekman dynamics) associated with the Findlater Jet controlled SLD during the summer monsoon. While in winter monsoon, cooling and convective mixing regulated SLD in the study region. Weak winds, high insolation and positive net heat flux lead to the formation of thin, warm and stratified sonic layer during pre and post summer monsoon periods, respectively.

Key words

Argo float sonic layer depth net heat flux wind speed Arabian Sea 


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Copyright information

© Korea Ocean Research and Development Institute(KORDI) and the Korean Society of Oceanography(KSO) 2008

Authors and Affiliations

  • TVS Udaya Bhaskar
    • 1
  • Debadatta Swain
    • 2
  • M Ravichandran
    • 1
  1. 1.Indian National Centre for Ocean Information ServicesIDA Jeedimetla (PO), Gajularamaram, HyderabadIndia
  2. 2.Space Physics Laboratory, Vikram Sarabhai Space CentreISROTrivandrumIndia

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