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A REVIEW OF THE PHYSICAL OCEANOGRAPHICCHARACTERISTICS IN THE ARABIAN GULFT.S. MURTY AND M.I. EL-SABHDepartment of Fisheries and OceansInstitute of Ocean SciencesP.O. Box 6000Sidney, B.C., Canada V8L 4B2DCpartement dOc6anographieUniversitC du QuCbec 2 Rimouski300 avenue des UrsulinesRimouski, QuCbec, Canada G5L 3A 1ABSTRACTThe meteorological and physical oceanographic systems that affect the Arabian Gulf (the“Inner Gulf’ of the Kuwait Action Plan Region) are considered. ’The so-called “Shamal” phenomenoncan cause significant positive and negative storm surges in the Gulf. Water balance is maintained byflow through the Strait of Hormuz, with surface inflow and deep outflow, resulting in a flushing timeof a few years. Tidal height patterns and residual currents also are discussed.INTRODUCTIONThe Arabian Gulf (also termed the Persian Gulf and the “Inner Gulf’ of the Kuwait ActionPlan Region) is a semi-enclosed sea measuring 1000 km in length; it varies in width from a maximumof 340 km to 60 km in the Strait of Hormuz (Fig. 1). It has an area of 226,000 km2 with an averagedepth of about 35 m. The Gulf is asymmetrical in profile with a more gentle gradient on thesouthwestern side. The northeastern coastline is marked by mountains and cliffs whereas thesouthwestern shore is often sandy.The continental area surrounding the Gulf is very arid, with considerable evaporation. Theresult is a classical Mediterranean-type circulation of surface inflow and deep outflow, with salinitybeing the most important determinant of density. As will be seen later, water circulation is governedby three factors: excess of evaporation, tidal currents and wind-driven currents.The physical oceanography of the Gulf has been reviewed by GRASSHOFF (1976),HUGHES and HUNTER (1979) and HUNTER (1982). A recent bibliography of the marine scienceof the region has been given by FARMER and DOCKSEY (1983). The purpose of this paper is toprovide a “state of the art” review of the known physical characteristics of the Gulf, following therecent symposiurdworkshop held in Saudi Arabia in October 1983 (EL-SABH, 1984).METEOROLOGICAL SYSTEMSThe Arabian Gulf is affected mainly by extra-tropical weather systems, whereas the Gulf ofOman is at the northern edge of tropical weather systems (MURTY and EL-SABH, 1984). Thus theStrait of Hormuz region forms the boundary between the generally west-to-east travelling extra-tropicalweather systems and east-to-west travelling tropical weather systems. One of the interesting weatherphenomenon in the region is the so-called “Shamal” (Arabic word for North) which is a sub-synoptic237