Evenings at Whitney Public Lecture Series -  April 8th, 2010 - Summary of “Ocean acidification: the other shoe for climate change. What could happen, what is likely, and what should we be doing?” Andrew Stamper, D.V.M., Dipl. A.C.Z.M., Epcot, The Seas.

When considering conservation of the ocean, one of the things we don’t often think about is the pH level in our oceans and how it affects our aquatic life.  Just as the ph of a swimming pool affects our eyes and skin, the ph in the ocean affects the creatures living in it.  For those of you that have ever cared for an aquarium or a swimming pool, you may notice that even minute shifts in ph can cause marked changes in your water quality.

Can you imagine what would happen if you dropped the ph by 30% in your pool or aquarium?  Water quality would drop dramatically and when this happens in the ocean, the regulating enzymes within the marine live would go up or down, which is within the physiology of most creatures but at the costs of valuable energy.  The short-range changes would be adaption, and long-range successful adaptation is called evolution.

Unfortunately, a 30% change in the pH is just what has happened in our oceans in the last 200 years. In the presentation last night, Dr. Stamper eloquently explained how and why the pH in our world’s oceans has been drifting downward at an ever-alarming rate, and the impact this shift is having on some oceanic organisms because the changes are happening at a rate to fast for marine life to adapt/evolve. He also demonstrated how the decline in pH is directly relative to the amount of CO₂ in our atmosphere. 

At the lecture hosted by the Whitney Laboratory for Marine Bioscience, Dr. Stamper presented a series of slides that connected the dots between increasing atmospheric CO₂ levels and ocean acidification.  The scientific equation looks like this: 

CO₂ (atmosphere) → ← CO₂ + H₂O → ← H₂CO₃ → ←  H⁺ + HCO₃- → ←  2H⁺ + CO₃²⁻

Essentially what that equation tells us is that when atmospheric CO₂ increases, so will the carbonic acids, the bicarbonates, and the carbonates in the ocean.  Dr. Stamper explained how this happens, and how it is also a function of solubility and how solubility relates to temperature, pressure and salinity.

Dr. Stamper had a simple way of explaining the relationship and it’s an easy concept to see in action.  First, open a cold bottle of beer.  The first thing you will notice is the immediate release of gas.  When the cap comes off, the pressure in the bottle drops and that allows the beer to “fizz.”  The fizzing is the release of CO₂. The first lesson here is that liquid at a lower pressure will release gas.  Now, pour that beer into a glass.  What you have in front of you is a liquid that is fully saturated with CO₂ at atmospheric pressure.  It gently bubbles because it is warming and finding equilibrium after the sudden release of pressure.  If you are a beer drinker, you also know there is very little salt in beer.  But what would happen if you added salt?  Just a teaspoon of salt added to that beer would cause it to erupt into bubbles, immediately releasing the captured CO₂.  Your beer would now be flat.  Why? Because salinity impacts the solubility of CO₂ in liquid, the lower the salinity, the more CO₂ a liquid can hold.  This exact phenomenon is happening in our oceans today, and the result is more than just the loss of a cold beer.  This would change if you would put a layer of CO₂ on top of the beer because the equation is always trying to balance itself.  If more CO₂ then it would be absorbed into the beer and “push” the equation in the other direction causing more acid.

I encourage all of you reading this to learn more about what you can do to reduce the amount of CO₂ in our atmosphere.  Small changes in your lifestyle can make a difference in preserving the delicate ecosystem that provides up to 90% of our Earth’s oxygen – our oceans.

To learn more about the affects of ph changes in our oceans and how to minimize release of CO₂ in everyday life, Dr. Stamper suggests you go to the following sites:

http://www.pmel.noaa.gov/co2/OA
http://www.ocean-acidification.net
http://climate.nasa.gov
http://www.nature.org/initiatives/climatechange/calculator

For more information about The Whitney Laboratory for Marine Bioscience go to http://www.whitney.ufl.edu and for more information on the Evenings at Whitney Lecture series go to: http://www.whitney.ufl.edu/lectures.htm

About the author: David Ulloa is the president and owner of Valeo Films Inc. (VFI), an independent film and video production company.  http://www.valeofilms.com

In addition to his professional activities, David maintains a national presence in the film industry through annual sponsorships and participation in numerous film and diving-related events.  David is also very enthusiastic about sharing his experiences by speaking at conventions, group meetings and dive clubs.