1. Introduction to the Oceans
EES Unit 4.1

2. Fast Facts 71% of Earth’s surface is covered by water
97% of all water on Earth is contained in oceans

3. Functions of the Oceans
Moderates climate
Ranges from -70°C (-94°F) to 55°C (131°F), only 125°C (257°F) difference
Mercury has a 610°C (1,130°F) range
Average is 14.6°C (58.3°F)
Average on Mars is -60°C (-80°F)
Reason: water is able to hold a lot of heat

4. Major part of the water cycle (the biggest part)
Most evaporation into clouds happens in the ocean
Huge biodiversity
Half of all species
Most biomass on Earth
Biomass: total mass of living organisms in a given area
Over 50% of oxygen production (through plankton)

6. Oceanic Divisions Vertical divisions
Photic zone: ocean zone in the top 200 meters of water that receives enough sunlight for photosynthesis to occur
Aphotic zone: ocean zone deeper than 200 meters where too little sunlight penetrates for photosynthesis to occur

7. Horizontal divisions
Intertidal (littoral) zone
Ocean zone that is closest to shore, between the high and low tide marks
Waves, tides, and currents operate here
Neritic zone
Ocean zone that lies over the continental shelf between the intertidal zone and the oceanic zone
Light able to penetrate here
Oceanic zone
Ocean zone that consists of the open ocean farther from shore than the neritic zone
Most sunlight does not penetrate

8. Ocean Water Salinity Where from?
Concentration of dissolved salts in salt water
Salts make up 3.5% of ocean water
Most common is regular salt (NaCl), worth 86% of all salts
Where from?
Most come from weathered rocks carried by rivers

9. Salinity and Density
Ocean is not uniform in temperature, salinity, currents, etc.
Varies greatly with latitude
Warm and saline near the tropics
Colder and less saline near polar regions

10. As temperature increases, salinity increases
Greatest density is where water is colder and more saline

11. Temperature and thermocline
Temperature lowers the deeper you go
A thermocline is the depth where the temperature drops very fast
Makes a barrier for ocean life

12. Light at Depth
Seawater does different things to different colors based on wavelength
Cool colors (blue, green = short wavelength) are scattered
Warm colors (red, yellow = long wavelength) are absorbed
Very little light makes it down past 200m (about 600 feet)

13. The World’s Oceans Arctic Ocean Atlantic Ocean Indian Ocean
Pacific Ocean
Southern Ocean