OS Ocean Science OS Ocean Sci. 1812-0792 Copernicus Publications Göttingen, Germany 10.5194/os-6-737-2010 Acoustic Doppler Current Profiler observations in the southern Caspian Sea: shelf currents and flow field off Feridoonkenar Bay, Iran Ghaffari P. 1 2 Chegini V. 3 Department of Geosciences, University of Oslo, P.O. Box 1022, Blindern, 0315, Oslo, Norway Department of Physical Oceanography, Iranian National Center for Oceanography, Western Fatemi, 1411813389, Tehran, Iran Department of Marine Engineering, Iranian National Center for Oceanography, Western Fatemi, 1411813389, Tehran, Iran 22 07 2010 6 3 737 748 Copyright: © 2010 P. Ghaffari 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://os.copernicus.org/articles/6/737/2010/os-6-737-2010.html The full text article is available as a PDF file from https://os.copernicus.org/articles/6/737/2010/os-6-737-2010.pdf

The results of offshore bottom-mounted ADCP measurements and wind records carried out from August to September 2003 in the coastal waters off Feridoon-kenar Bay (FB) in the south Caspian Sea (CS) are examined in order to characterize the shelf motion, the steady current field and to determine the main driving forces of currents on the study area. Owing to closed basin and absence of the astronomical tide, the atmospheric forcing plays an important role in the flow field of the CS. The lasting regular sea breeze system is present almost throughout the year. This system performs the forcing in diurnal and semi-diurnal bands similar to tides in other regions. In general, current field in the continental shelf could be separated into two distinguishable schemes, which in cross-shelf direction is dominated by high frequencies (1 cpd and higher frequencies), and in along-shelf orientation mostly proportional to lower frequencies in synoptic weather bands. Long-period wave currents, whose velocities are much greater than those of direct wind-induced currents, dominates the current field in the continental shelf off FB. The propagation of the latter could be described in terms of shore-controlled waves that are remotely generated and travel across the shelf in the southern CS. It has also been shown that long term displacements in this area follow the classic cyclonic, circulation pattern in the southern CS.

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