The steady flow of ocean water in a prevailing direction

Ocean Currents Driven by several factors Tides Wind Thermohaline circulation

Tidal Currents Occur with the rise and fall of the tides Near the shore Bays Estuaries

Coastal Currents Depend on Winds Waves Land formations

Coastal Currents Winds that blow along the shoreline—longshore winds—affect waves and, therefore, currents Longshore currents are generated when a wave train reaches the coastline and release bursts of energy May form rip currents (not rip tides) - a localized current that flows away from the shoreline toward the ocean

Surface Currents Occur on the open ocean Driven by a complex global wind system

Surface Currents – Coriolis Effect Due to Earth’s rotation The Earth rotates faster at the Equator than it does at the poles Earth is wider at the Equator; point on the Equator has farther to travel in a day /es1904page01.cfm

Surface Currents – Coriolis Effect Circulating air or wind is deflected by the Coriolis Effect

Surface Currents Global winds drag on the water’s surface Caused movement in the direction that the wind is blowing Results in the deflection of surface ocean currents to the right in the Northern Hemisphere (in a clockwise spiral) and to the left in the Southern Hemisphere (in a counter-clockwise spiral) Called gyres Occur north and south of the equator Not at the equator Coriolis effect is not present