1. When you hear the term “Carbon Dioxide”, what do you think of?

2. Today we’re talking about:
“The other carbon dioxide problem”

3. How can sediments & ocean composition help up understand changes in atmospheric composition?
Further reinforce significance of oceans to Weather & Climate
We’re using Ocean Acidification as an example to study this
This learning objective will transition us into our next unit…THE ATMOSPHERE!! 

4. Chemistry review… pH = a measure of how acidic or basic a solution is
Depends on the concentration of H+ ions
Low pH = acidic
High pH = basic

5. Bellwork 2/22 What is ocean acidification?
Please, take out your Ocean Acidification note sheet (white paper) and your Ocean Acidification Activity (pink paper)
What is ocean acidification?
Why is the ocean changing in pH?

6. What does pH have to do with the ocean?
Ocean acidification: reduction in the pH of the ocean over an extended period time (NOAA)
Primarily caused by the uptake of CO2 from the atmosphere
Phenolphthalein demo

7. Causes of increased CO2:
Burning fossil fuels
Transportation is a huge part of this…here’s a bit of irony “The 11-day international Copenhagen Climate Change Conference in Denmark generated 41,000 tons of CO2. U.S. delegates alone produced enough CO2 to fill 10,000 Olympic swimming pools”
Manufacturing
Deforestation
Pollution
Biological processes

8. How much CO2 can the ocean absorb?
The total amount of any gas seawater can absorb depends on temperature and salinity
The solubility of gases decreases with increasing temperature
so cold water will take up more CO2 and less will be escaping to the air
Remember this relationship!
Temperature or
Salinity
Amount of gas
seawater can absorb
Which oceans might be more affected by ocean acidification?

9. The ocean is a carbon sink…
The ocean absorbs CO2 from the atmosphere
Physical and biological processes move some of the carbon to the deep ocean where it is stored
What kind of physical processes?
Currents
Temperature & salinity differences

10. Consequences of Ocean Acidification
Lab activity
When dissolved in water, carbon dioxide forms carbonic acid that primarily dissociates into bicarbonate and hydrogen ions
Some of the excess hydrogen ions combine with carbonate, decreasing carbonate availability to marine organisms.

12. How do we study ocean acidification?
Biological studies
Sediment studies
Monitoring devices with CO2 sensors
Buoys
Gliders

13. How much has the ocean really changed in pH?
Since the beginning of the Industrial Revolution, the pH of surface ocean waters has fallen by 0.1 pH units (NOAA)
Since the pH scale is logarithmic, this change represents approximately a 30 percent increase in acidity. (NOAA)