Ocean Currents

What causes surface currents?

• The moon's gravitational pull

• Friction from the wind on the water

• Underwater volcanic activity

• Earth's rotation

How fast can surface currents move?

• Up to 10 km/day

• Up to 50 km/day

• Up to 100 km/day

• Up to 200 km/day

What is the main idea of the section titled "Surface Currents"?

• Surface currents are caused by underwater earthquakes

• Surface currents are driven by wind and move water horizontally

• Surface currents are the result of ocean floor movements

• Surface currents are only found near the equator

How many major ocean gyres are there?

• Three

• Four

• Five

• Six

What type of winds are Earth's major wind belts?

• Trade winds

• Prevailing winds

• Cyclones

• Hurricanes

What causes upwelling to occur?

• The rotation of the Earth

• The gravitational pull of the moon

• Wind blowing across the ocean's surface

• The melting of polar ice caps

What is denser than warm water?

• Freshwater

• Cold water

• Salty water

• Ice

What is the main difference between upwelling and density currents?

• Upwelling is caused by wind, density currents by changes in density

• Upwelling occurs in rivers, density currents in oceans

• Upwelling is horizontal, density currents are vertical

• Upwelling is warm, density currents are cold

What is the role of the Sun in the Great Ocean Conveyor Belt?

• It cools the water

• It warms the water

• It freezes the water

• It evaporates the water

What is the primary cause of upwelling?

• Changes in temperature

• Wind

• Earthquakes

• Tides