Which statement describes a Rotary Tidal Current?

• A. Occurs when direction of flow NOT restricted by barriers
• B. Occurs when direction of flow RESTRICTED by barriers
• C. Flows continuously
• D. Only occurs in rivers

Answer: (A)

Rotary tidal current means the tidal flow forms a circular pattern around a center rather than moving in a straight line. This happens when the water can move freely, without barriers such as islands or jetties constraining the flow. In open or unobstructed coastal areas, the combination of the tide’s movement and the Coriolis effect tends to make the surface water rotate as the tide rises and falls. Barriers alter this by guiding the water along channels or around obstacles, which reduces or changes the rotary motion. The current reverses with the tide, so the rotation direction changes during flood and ebb. It can occur in open coastal waters or harbors, not just in rivers, and it’s not simply a continuously flowing, unchanging current.