Ocean Science www.ocean-sci.net 1812-0784 1812-0792 5 1 2009 10.5194/os-5-1-2009 http://www.ocean-sci.net/5/1/2009/ http://www.ocean-sci.net/5/1/2009/os-5-1-2009.html http://www.ocean-sci.net/5/1/2009/os-5-1-2009.pdf 1 12 2009-01-12 The structure of the Persian Gulf outflow subjected to density variations A. A. Bidokhti bidokhti@ut.ac.ir M. Ezam Institute of Geophysics, University of Tehran, P.O. Box 14155-6466, Tehran, Iran Faculty of Marine Science and Technology, Science and Research Campus, IAU, P.O. Box 14155-775, Tehran, Iran Oceanographic data and a dynamic model are used to consider the structure of Persian Gulf outflow. This outflow influences the physical properties of Oman seawater which appear in the CTD profiles of the Oman Sea. The observations show that thickness of the outflow, which is banked against the Oman coasts due to the earth rotation, is about 200 m with tongues extending east and north that may be due to the internal waves. A simple dynamical model of the outflow based on potential vorticity conservation is used to find the horizontal extension of the outflow from the coast. Typical mass transport estimate by the outflow is about 0.4 Sv, which is larger than those reported by others. This may be due to the fact the model is inviscid but the outflow is influenced by the bottom friction. Variability of the outflow structure may reflect the changing ecosystem of the Persian Gulf. Any change of the outflow source, the Persian Gulf Water (PGW), say salinity increase due to excessive evaporation (climate factor) or desalination (anthropogenic factors) of the PGW may change the outflow structure and the product waters in the Oman Sea. Hence, one can test different scenarios of changing the outflow source, the Persian Gulf Water (PGW), say by salinity increase due to excessive evaporation or desalination to estimate changes in the outflow structure and the product waters in the Oman Sea. The results of the model show that these can increase the outflow width and mass transport substantially. Bidokhti, A. A.: Shear induced splitting of a plume outflow in a stratified enclosed basin, Indian J. Mar. Sci., 34(2), 192–211, 2005. Bower, A. S., Hunt, H. D., and Price, J. F.: Character and dynamics of the Red Sea and Persian Gulf outflows, J. Geophys. Res., 105(C3), 6387–6414, 2000. Chao S. Y., Kao, T. W., and Al-Hajri, K. R.: A numerical investigation of circulation in the Persian Gulf, J. Geophys. Res., 97(C7), 11 219–11 236, 1992. Gill, A. E.: Atmosphere-Ocean Dynamics, Academic Press, 662 pp., 1982. Griffiths, R. W. and Bidokhti, A. A.: Interleaving intrusions produced by internal waves; a laboratory experiment, J. Fluid Mech, 602, 21-9-239, 2008. Privett, D. W.: Monthly charts of evaporation from the North Indian Ocean, including the Red Sea and the Persian Gulf, Quart. J. Roy. Meteorol. Soc., 85, 424–428, 1959. Pous, S. P., Carton, X., and Lazure, P.: Hydrology and circulation in the Strait of Hormuz and the Gulf of Oman result from the GOGP99 Experiment, J. Geophys. Res., 109, C12038, doi:10.1029/2003JC002146, 2004. Qasim, S. Z.: Oceanography of the northern Arabian Sea, Deep-Sea Res., 29, 1041–1068, 1982. Reynolds, R. M.: Overview of physical oceanographic measurements taken during the Mt Mitchell Cruise to the ROPME Sea Area, Mar. Pollution Bull., 27, 35–59, 1993. Swift, S. A. and Bower, A. S.: Formation and circulation of dense water in the Persian Gulf, J. Geophys. Res., 108(C1), 3004, doi:10.1029/2002JC001360, 2003. Wong, A. B. D., Griffiths, R. W., and Hughes, G. O.: Shear layer driven by turbulent plumes, J. Fluid Mech., 434, 209–241, 2001.