Bellwork 2/14 Give two specific examples of how studying ocean floor sediments can help us understand ocean mechanics (currents, composition, chemistry, ect.)

Then we’ll begin Unit 2—THE ATMOSPHERE!  Coming up… Tuesday 2/6: Finish ocean water properties (density) Intro to Sediments Thursday 2/8: Lab Quiz!! Discuss ocean sediments Begin Sediment Lab Monday 2/12: Finish Sediment Lab Wednesday 2/14: Begin Ocean Acidification Notes & activity Friday 2/16: Wrap up Ocean acidification & Loose ends Review Ocean Test Tuesday 2/20! Then we’ll begin Unit 2—THE ATMOSPHERE! 

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

“The other carbon dioxide problem” Today: “The other carbon dioxide problem”

Today: How can ocean composition help up understand changes in atmospheric composition? We’re using Ocean Acidification as an example to study this This learning objective will transition us into our next topic…THE ATMOSPHERE!! 

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

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 PHPH demo

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

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?

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

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.

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

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)