Ocean Currents and Climate

SPI 0607.8.3Describe how temperature

differences in the ocean account for currents.

Ocean water contains streamlike movements of

water called ocean currents. Currents are influenced by a number of factors, including weather, the Earth's rotation,

and the position of the continents.

There are twotypes of ocean

currents:

Surface Currents:Horizontal, streamlike

movements of water that occur at or near the

surface of the ocean are called surface currents

Surface Currents:The Gulf Stream is one of

the longest surface currents.

Surface Currents:Surface currents are controlled by three

factors which keep surface currents flowing in

distinct patterns around the Earth.

Surface Currents:1. Global Winds - winds

that blow across the Earth's surface to create surface currents in the

ocean.

Surface Currents:Different winds cause

currents to flow in differentdirections. Near the equator, the winds blow ocean water

east to west, but closer to the poles, ocean water is blown

west to east.

Surface Currents:2. Coriolis Effect - The Earth's rotation causes

wind and surface currents to move in curved paths rather than in straight

lines..

Surface Currents:The Coriolis Effect causes

surface currents in the Northern Hemisphere to turn clockwise, and surface currents in the Southern Hemisphere

to turn counterclockwise.

Surface Currents:3. Continental deflections -When surface currents meet

continents, the currents deflect, or change direction.

Surface Currents and Climate

Surface currents greatly affect the climate in many parts of

the world. Some surface currents warm or cool coastal

areas year-round.

Surface Currents and Climate

Surface currents are affected by the

temperature of the water in which they form.

Surface Currents and Climate

Surface currents are classified as warm-water

or cold-water.

Surface Currents and Climate

1. Warm-water currents begin near the equator

and carry warm water to other parts of the ocean.

Surface Currents and Climate

2. Cold-water currents begin closer to the poles and carry cool water to

other parts of the ocean.

Deep Currents:Streamlike movements of

ocean water located far below the surface are called

deep currents. Deep currents are not directly

controlled by wind.

Deep Currents:Deep currents form in

parts of the ocean where water density increases.

Deep Currents:The density of ocean water is affected by

temperature and salinity

Deep Currents:Decreasing the temperature

of ocean water and increasing the water's

salinity increase the water's density.