OCEAN CURRENTS 1 01 What causes currents 1

OCEAN CURRENTS

1. 01 What causes currents?

1. 01 What causes currents? • Prevaling Winds: – winds that blow from a single general direction over a particular point on the Earth's surface. – Examples: • Westerlies • Trade Winds

Wind belts

1. 01 What causes currents? • Changes in Water Temperature: – Cold water sinks, warm water rises. This creates a movement of water based on radiation from the sun.

1. 01 What causes currents? • Coriolis Effect – Deflection of winds and ocean currents caused by Earth’s rotation

1. 01 What causes currents? • Changes in Salinity – Saline water (salty water) becomes more dense and sinks. Causes deep water currents.

1. 01 What causes currents? • Uneven Heating – Differences in solar radiation from the sun causes ocean water to heat at different intensities, causes the rising and sinking of water. – WARM water expands and rises – COLD water contracts and sinks

1. 01 What causes currents? • Basin Shape – The continents form a barrier which causes ocean water to be deflected and divided.

1. 02 Label major surface currents • HOMEWORK – Use your book p. 429 to do this!

Currents regulate Earth’s climate

1. 03 Ocean Terms: • Gyre: large system • Boundary Current: of rotating ocean currents, involved with large wind movements. ocean currents with dynamics determined by the presence of a coastline. – Western + Eastern

Ocean Gyres

Deep Currents • Thermohaline circulation- caused by • • density and temp. difference Salty water sinks; cold water sinks Global conveyor belt

Gulf Stream