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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.
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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.
How does a wave move? ENERGY Wave/Wind Simulation
How Waves Affect the Shoreline • Longshore drift
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
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 turn 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.
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.