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Abstract Convergence Zone (RSCZ) and the monsoonal Inter Tropical Convergence Zone (ITCZ). The RSCZ, whose influence is most noticeable in the west of the country, is active from March to May and to some extent in the autumn, while the ITCZ reaches Yemen in July- September, moving north and then south again so that its influence lasts longer in the south. Both convergence zones produce precipitation in the form of convective storms of high intensity with short duration and limited areal extent, although the ITCZ storms have a larger extent than those produced by the RSCZ. The relative importance of the RSCZ and ITCZ in different parts of the country is reflected in the seasonal rainfall distribution (Shahin, 2007). Seasonal sea level variability in the Arabian Sea is mainly consistent with steric sea level changes except in places where the atmospheric sea level pressure plays a significant role. The tides in the Arabian Sea are predominantly co-oscillating due to its gently sloping bottom along with broad shelves along the west coast of India and narrow shelves elsewhere, and the wide connection to the rest of the Indian Ocean. Therefore, along the Arabian Sea coasts the tides are semi diurnal with diurnal inequality. They change from predominantly semi diurnal in the northeast quadrant to predominantly diurnal in the southwest quadrant (AL-Subhi, 2007). Over the whole period for which records was available, extending over perhaps 100 years, some (20-25) storms have been traced to the west of 60° E. It must be remembered, however, that in early years records are probably incomplete. Storms are most likely to be encountered in May-June and October- November. In those months most of the storms in the Arabian sea travel towards the west or west-north-west and quite a large proportion penetrate beyond the 60th meridian even as far as the Arabian coast. Not infrequently they appear to dissipate near the Khorya Morya islands. Most of the storms are fully developed when they enter the region, and usually continue to travel towards the west or north-west, though some recurve to north and north-east. A few storms have been known to form within the region and to move north and north-east. Records from south-east Arabia are scanty but it appears from the charts that storms penetrate farther west in May than in the post-monsoon period so that it is in that month that the Arabian coast is most likely to be visited. The tropical cyclone in the area of the Arabian Sea and the Gulf of Aden considered the main cause of natural disasters on coastal communities and facilities scattered along the coast and caused by strong winds and high waves, high tides and floods resulting from rain associated with such depressions. According to many previous studies to the extent of disasters and damage on the region, which led to the creation of environmental changes for the region. In general the region of the Arabian Sea and the southern coast of Oman Cyclonic exposure particularly at ARB2, 2002 that struck the Salalah region of Oman. The storm brought the heaviest rainfall totals to Dhofar in 30 years, causing flooding and creating rivers in wadis and several people drowned after their vehicles were swept away by the flooding. The storm caused locally heavy damage, totaling $25 million (ESCAP, 2003), in June 2007 to Hurricane Gonu, which caused significant damage in coastal construction and the losses in lives, in 2008 the southern coast of eastern Yemen also exposure to a tropical cyclone, killing many of the individuals and the destruction of many coastal villages, which led to the displacement of more than 22000 people from their homes. Prediction of the frequency of Tropical Cyclone (TC) over the oceanic region are veryimportant as they would be helpful for both short term and long term planners towards |