1. Properties of Ocean Water
Ch Part 2

2. Temperature of Ocean Water
Like salinity ocean temperature varies depending on depth and location

3. Surface Water
The ocean absorbs infrared wavelengths of the that heat the surface of the ocean
The surface water mixes with the water below it, keeping the temperature relatively the same to a depth of 100m to 300m
The total amount of solar energy that reaches the surface is much greater at the equator= warmer tropical water

4. The polar regions are colder and covered with “pack ice”
Pack Ice- floating layer of sea ice usually no more than 5 m thick.
Insulates water below it and keeps it from freezing

5. Thermoclines Zone of rapid temperature drop
Basically, the sun cannot directly heat the ocean water below the surface layer --causing a sharp decrease in water temperature

6. Thermoclines exist because warm water near the surface is less dense
The warm water sits on top and does not mix with the cooler water below

7. Deep Water Temperatures
Deep zones below 400m is usually near 2C
The colder the water = more dense water holding more dissolved gases

8. Density of Ocean Water
Density- the ratio of the mass of a substance to the volume of the substance (g/cm3)
Density of pure water = 1 g/cm3

9. Factors Affecting Density
Salinity
The large amount of dissolved solids make ocean water denser than pure water
Density range= g/cm3 to g/cm3

10. Temperature Ocean water becomes denser as it becomes colder
Temperature affects density more than salinity
Therefore colder regions are the most dense

11. Color of Ocean Water
Color of ocean water is determined by the way it absorbs or reflects sunlight
Most colors are absorbed= only blue is reflected

12. Why is Color Important?
Phytoplankton –small marine plants that provide food for many ocean species
Only absorb red and blue—reflect green
Scientist study color to find phytoplankton