1. Essential Question: What physical characteristics make up an ocean environment and how do they vary? http://www.youtube.com/watch?v=tzBJy6BXf5Y

2. Activites: Salt water vs. Fresh water Freezing time: Density: Observations: TimeFrozen? Y/NDescribe

3. Notes: Ch. 4.3Ocean Water Chemistry Salinity The total amount of dissolved salt in a sample of water The ocean is 35 parts salt per thousand on average Lower near the ocean’s surface b/c of precipitation Lower near the mouths of rivers b/c they dump fresh water into the ocean Evaporation increases salinity – water evaporates and leaves salt behind (hot and dry climates have more salinity – polar climates have more salinity b/c the water freezes and leaves the salt behind)

4. Notes: Ch. 4.3Ocean Water Chemistry Effects of Salinity Lowers the freezing point by about 2 degrees Celsius -- interferes with the formation if ice crystals Higher density than fresh water -- mass of 1L of salt water is greater than 1L of fresh water -- has greater buoyancy -- Density= Mass/Volume

5. Concentration Activity: What difference did you notice between the 2 samples? What caused the difference? How does this explain concentration?

6. Notes: Ch. 4.3Ocean Water Chemistry Temperature SURFACE TEMPERATURES vary with location and the seasons Ocean absorbs “nrg” from the sun -- just like land, the closer to the equator, the warmer it is Warm water is less dense than cold water, so it floats on the surface -- as you go deeper into the ocean, the water becomes colder and more dense -- colder temperatures = water molecules are closer together = 1L of cold H2O is more dense than 1L of warm H2O

7. Notes: Ch. 4.3Ocean Water Chemistry Gases in Ocean Water Ocean organisms use oxygen (O2) and carbon dioxide (CO2) Much more CO2 in the oceans than in the air -- algae use it for photosynthesis (food making) -- provides carbon needed by coral to make their hard skeletons O2 is more plentiful in air -- most O2 in the ocean is near the surface -- comes from the air and algae in the ocean (product of photosynthesis) -- affected by water temperature = cold water has more than warm water

8. Notes: Ch. 4.3Ocean Water Chemistry Gases in Ocean Water Ocean organisms use oxygen (O2) and carbon dioxide (CO2) Much more CO2 in the oceans than in the air -- algae use it for photosynthesis (food making) -- provides carbon needed by coral to make their hard skeletons O2 is more plentiful in air -- most O2 in the ocean is near the surface -- comes from the air and algae in the ocean (product of photosynthesis) -- affected by water temperature = cold water has more than warm water

9. The Water Column: Temperature decreases Pressure increases

10. Notes: Ch. 4.3Ocean Water Chemistry Changes with depth As you descend through the ocean, the water temperature decreases -- surface zone = warmest, avg. temp 17.5 degrees Celsius = 100-500 meters -- transition zone = avg. temp 4 degrees Celsius = bottom of surface zone to 1km -- deep zone = avg. temp 3.5 degrees Celsius = 1km to the ocean floor

11. Pressure Activity – techbook: Materials: Bottled water – 1 L Duct tape Large push pin Meter stick Permanent marker Paper towels A table Roll of butcher paper Writing paper or science notebook for recording ideas

12. Pressure Activity – techbook: Hole #Distance from topWater distance 1 (top) 2 3 4 5 (bottom) 1.Draw a sketch of the bottle from the side. 2.From which hole did the water spray the farthest? Why? 3.From which hole did the water spray the shortest? 4.Did you see a pattern? 5.How does this experiment relate to the water pressure at various depths of the ocean?