Post on 28-Dec-2015
Oceans
• 74% of the Earth’s surface• 3.5% Salinity• Major oceans are: Pacific, Atlantic, Indian,
Southern, Arctic• Average depth of 3790 m (12,430 ft.)• Color blue because the water absorbs red
photons.
• Most waves are caused by surface winds.
How does a wave move?
ENERGY
Wave/Wind Simulation
The main difference between
Waikiki and the North
Shore
The exception to wind-caused waves would be a tsunami.
Destructive Force of Tsunami Waves
How Waves Affect the Shoreline
• Longshore drift
Waves create currents
Back to Salinity• The Ocean can vary from 34-37
parts/thousand. These variations occur because of rivers, freezing ice and evaporation.– Dead Sea can be
up to 300-400 parts/thousand(*GSL is 50-270)
Salinity and Gases
• Lowers freezing temperature (acts as antifreeze)
• Increases density, thus it has greater buoyancy
• Most oxygen found at surface (less than air)• CO2 is 60 times greater than in air! Helps with
photosynthesis and to build coral.
Currents
• Move because of winds and the spin of the EarthCoriolis effect.
• Winds are able to move the top 400 m of the ocean. Some currents move slow, some move deep.
• Ocean currents carry heat from place to place.• Sun warms water more at equator
Coriolis Effect• Because of the rotation of the Earth, currents t
urn to the right in the northern hemisphere and to the left in the southern hemisphere.
Intertidal Zone
Neritic Zone
Surface Zone
Deep Zone
Layers of the Ocean
• The sun can only penetrate so far, and most life depends on photosynthesis.
• Most biotic factors will be found near the surface (sunlit zone). Even higher concentrations of life are found near the shore where upwelling occurs.
Upwelling
El Niño
• Occurs every 2-7 years in the Pacific Ocean• Lasts for 1-2 years.• Normally temps are 60ish off the coast and up
to 80s in the central and west Pacific.
• Fish along the American coast die off.• Creates strange weather patterns throughout
the hemisphere and around the world.
Opposite event is La Niña
• Results from buildup of subsurface cold water. • Increases the upwelling on the coast of S.
America.• This cycle happens after El Niño and especially
after a really strong one.