Warm Up

Name 2 processes that drive ocean currents.

Ocean Currents

Movement of Ocean Water

Oceans are always in constant movement caused by: Variations in Density

Wind

Specific Heat of Water Water has a high specific heat (4.184 J/g*C)

It takes a lot of energy to heat up water and cool it down

Density Currents

Density Currents-Ocean Currents that move due to differences in density Global Conveyor Belt

Ocean Currents Upwelling Currents – Occur when wind moves seawater at the surface and

new water from below replaces it

Critical Thinking #1 How might upwelling currents be beneficial to life in the ocean? Explain.

Coriolis Effect Coriolis Effect-The rotation of the Earth results in wind

blowing in a circular motion Wind blows to the right in the Northern Hemisphere

Wind blows to the left in the Southern Hemisphere

Gyres Gyres are large circular current systems that flow from

north to south and are caused by the Coriolis Effect 5 major gyres:

2 in the Pacific Ocean

2 in the Atlantic Ocean

1 in the Indian Ocean

Surface Currents Surface Currents are currents that affect the upper most

portions of the surface Surface Currents that flow towards the equator generally bring cold water

Surface Currents that flow away from the equator generally bring warm water

Ocean Currents

Deep Currents – Move slowly beneath surface, primarily caused by differing water densities

Critical Thinking #2 What processes might cause changes in density that form deep ocean

currents?

Climate Impact Coastal Areas: Have a high amount of water vapor in

the air. Summer will be cooler

Winters will be warmer

Climate Impact In cities located further from the coast there is less water

vapor in the air

Summers will be very hot

Winters will be very cold

Tides Tides – Daily changes in the level of the ocean surface

2 high tides and 2 low tides each day caused by gravitational pull of primarily the moon, but also the sun

High Tides and Low Tides High (Flood) Tides – Occur on side of Earth facing and opposite the moon, due to

both gravity facing and centrifugal force opposite

•Low (Ebb) Tides – Occur on sides halfway between the moon

Spring Tides and Neap Tides

Neap Tides = Small tidal range, when moon and sun are perpendicular

•Spring Tides = Highest and lowest tides, when moon and sun align

Critical Thinking #3 Why are spring tides stronger than neap tides? Explain.