1. Oceanography

2. Earth’s Oceans Earth is a special planet because of liquid water
71% of Earth’s surface is water
Ocean divided by continents

3. 4 Major Ocean Divisions Pacific Ocean Atlantic Ocean Indian Arctic
Volume 724 million cubic kilometers
Atlantic Ocean
322 million cubic kilometers
Indian
292 million cubic kilometers
Arctic
12 million cubic kilometers

4. Ocean Formation Two theories Out-gassing Big Splat
Volcanic vents released gases that cooled to form our oceans
Extraterrestrial comets delivered our water

5. Plate Tectonics Effect on Oceans
Plate tectonics causes lithosphere to move
As crust changes, oceans change shape
245 mya continents formed Pangaea
Oceans formed Panthalassa

6. Characteristics of Ocean Water
Chemical composition is similar to
NaCl, Sodium Chloride, table salt
Chlorine is the most abundant element
Salinity
Measured amount of salt and solids in a given amount of liquid

7. Factors affecting Salinity
Evaporation
Hot dry climate increases evaporation
Less water more salt = high salinity
River outlets/precipitation
Increase of fresh water dilutes ocean water = lower salinity
Currents
Currents mix water causing water to become diluted = lower salinity

8. Temperature Zones Water Column: vertical aspect of ocean
As depth Increases
Pressure increases, Temperature decreases
3 Zones
Surface
Transition/Thermocline
Deep zone

9. Surface Zone Warm top layer Extends down 300 meters
Sunlight warms only top 100 meters
How does zone maintain temperature?
Average temp is 24°C
Varies with latitude and time of year
Rather swim near Alaska or Florida?
Swim during summer or winter?

10. Transition/Thermocline
Range is 300 to 700 meters
Water temp decreases the greatest in this zone
Begins at 24°C
Ends at 5°C

11. Deep Zone Range 700 to ocean floor 1,200 Meters Average temp is 2°C
Deepest part of the ocean is below zero, yet water doesn’t freeze, why?

12. Water Cycle
Cycle that links all Earth’s solid, liquid and gaseous water. 3 parts are:
Condensation
Gas to a liquid
Precipitation
Solid or liquid water falls to earth
Evaporation
Liquid to a gas