Ocean Acidification: Another Symptom of Global Warming


I attended the 8th Annual Roger Revelle Commemorative Lecture at the Smithsonian on March 5th entitled “What Corals Are Dying To Tell Us About CO2 and Ocean Acidification.” Ken Caldeira, the presenter, spoke to about 500 people in a packed auditorium about the current trends worldwide in coral reef health. He expressed concern that although popular media talks about the effect CO2 has on the air, there isn’t much spoken about the effect CO2 has on the oceans. And the oceans are not an indefinite sink for CO2.

Carbon Dioxide deposits in the oceans and the molecules bind with the water molecules to create Carbonic Acid. If there is too much Carbonic Acid, it can change the pH of water and is corrosive to the shells and skeletons of marine organisms coated or composed of calcium carbonate, such as corals. The acid literally eats away at the organism.


Why is this important? As pollution increases in our global ecosystems, biodiversity is reduced and food chains can be disrupted. In the case of corals, they are the food source, breeding ground, and home for a whole system of organisms, the diversity of which is sometimes compared with rainforests. If the current deposition trend continues, oceans will loose not only corals, but the ecosystem that corals sustain as well.


Visible loss of coral has been recorded worldwide. Though CO2 exacerbates the destruction of corals, it is not the only factor. Eutrophication, temperature changes, and human development have also taken their toll. It will take tens of thousands of years for the oceans to recover chemically to normal levels. The current situation of CO2 deposition in the oceans can be compared with the meteorite theorized to have hit in the Yucatan 65 million years ago that caused a great amount of chemical change in the ocean (along with temperature change) and resulted in a biological impact from which the corals did not recover for 10 million years.


The solution offered by Dr. Caldeira was two-fold. More research must be done on the oceans, we currently know so little about the effects of long lasting events. And we must change our current energy production and consumption. The average American is responsible for producing 120 pounds of CO2 per day, 40 pounds of which deposit in the oceans. This is five times the global average. Natural release of CO2 is 50-70 times less than this. This is yet another reason we as a global community need to take energy production alternatives seriously and move away from our dependency on fossil fuels.


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Dr. Jennifer Veilleux is a geographer, writer, and artist. For more than a decade, she has worked on scientific research and security issues facing water resources shared across political boundaries. Research and curiosity has taken her to more than 50 countries on 5 continents, often to remote locations and marginalized communities. Veilleux takes portraits of people she encounters in her field work and recently released a collection, Portraits from Rivers of Change, that can be viewed here: www.jenniferveilleux.com. These portraits highlight two separate communities, one on the Mekong River the other on the Blue Nile River, facing relocation due to dam development. Dr. Veilleux works for Florida International University as a post doctoral associate for the Institute of Water and Environment and manages SELVA, the Serengeti-Lake Victoria Sustainable Water Initiative, a research project on water security of the Mara River in the Upper Nile basin of Tanzania. She maintains a blog, The Way of Water, dedicated to news and commentary about development on the Nile and Mekong, general water resources issues, and special topics related to women in science. She lives in Miami with her cat Mr. FC Sweet Tea.