oceans surface currents. what are surface currents? surface currents are horizontal, streamline...

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Oceans Surface Currents

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Surface current formation As wind blows across the ocean, it drags water along with it creating strong currents. Because the wind’s reach is limited, these surface currents only run about 200 meters (656 feet) deep. Short lived winds create temporary surface currents. Constant winds create more permanent currents that flow strongly on a fixed course.

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Page 1: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

OceansSurface Currents

Page 2: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

What are surface currents?

• Surface currents are horizontal, streamline movements of water that occur at or near the surface of the ocean.

• Surface currents can reach depths of several hundred meters and lengths of several thousand kilometers, and can travel across oceans.

Page 3: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Surface current formation

• As wind blows across the ocean, it drags water along with it creating strong currents. Because the wind’s reach is limited, these surface currents only run about 200 meters (656 feet) deep.

• Short lived winds create temporary surface currents. Constant winds create more permanent currents that flow strongly on a fixed course.

Page 4: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

What controls surface currents?

• 1. Global Winds• 2. Coriolis Effect• 3. Continental Deflection

Page 5: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

• The sun heats the Earth’s atmosphere unevenly, creating very warm, high-pressure areas around the equator, and cool, low pressure areas toward the poles. As the warm air moves to low pressure areas, wind is created. Uninterrupted, wind patterns would run in straight lines from pole to pole.

Wind Creation

Page 6: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

What factors contribute to surface current formation?

1. Global Winds- winds that blow across the Earth’s surface create surface currents. They act as a heat transfer system. Global winds are due to the unequal heating of earths surface.

Page 7: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

2. The Coriolis Effect – the apparent curving of moving objects from a straight path due to the Earth’s rotation.

Because of the Earth’s rotation wind is forced right or left, depending on the hemisphere it is in.

Page 8: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

3. Continental Deflection – when surface currents meet a continent it deflects the movement of the current. Currents change directions by hitting the Currents change directions by hitting the continents or landmassescontinents or landmasses

The Gulf Stream deflects off the coast of North America and flows across the ocean to the British Isles. As a result, the British Isles have a milder climate than Canada.

Page 9: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Why are some surface currents cold and others are warm?

Warm water surface currents originate in the tropics and flow north and south from the equator. As the water moves farther north it cools and sinks. The colder water on the surface then moves north or south from the poles and warms as it gets closer to the tropics.

Page 10: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…
Page 11: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

California current along the coast of California is a cold water current,

causing cooler water temperatures.

Page 12: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

The Gulf Stream is a warm water current that flows along the gulf and Florida, causing warmer

water temperatures.

Page 13: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Gulf Stream current.

Page 14: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Currents and ClimatesCurrents and Climates

• Surface currents gently cool or warm the Surface currents gently cool or warm the coastal areas year round coastal areas year round

• Some surface currents change their circulation Some surface currents change their circulation pattern causing changes in the atmosphere pattern causing changes in the atmosphere that affect the climate in many parts of the that affect the climate in many parts of the world. world.

Page 15: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Warm Water Currents and Warm Water Currents and ClimatesClimates

Warm water currents create warmer climates in coastal areas.

Page 16: Oceans Surface Currents. What are surface currents? Surface currents are horizontal, streamline movements…

Cold Water Currents and ClimatesCold Water Currents and ClimatesCold water current bring cooler

climates into areas.