The Study of Current and Tidal Asymmetry in theSoutheastern Shallow Waters of Kish Island-Iran

Tidal asymmetry in the south-east of the Kish Island (Persian Gulf) is investigated in this study using water-level and velocity profile (3 layers) data recorded by an ADCP for a period of 35 days at a station with the depth of 12m. In the whole water column, the dominant current is forced by tide which periodically alters velocities in east (in high tide) and west (during low tide) directions. The weak residual current diverts current field as partially southward especially in two deep layers. Due to atmospheric forces, residual current partially disperse observed current from east-west direction in the upper layer. Tide is mixed mainly semidiurnal at the study area and principal triad tides K1-O1-M2 produce 13.66-day periodic asymmetries including an ebb-dominance and a flood-dominance during spring and neap tides respectively. Although, the contribution of the ebb-dominance asymmetry induced by this triad is dominant in all 35 days. During the whole period, shallow water components induce a flood-dominance asymmetry condition.