Modest mermaids of the future may have to find a new source for bikini tops as ocean acidification damages the shells of clams, scallops and oysters, while humans lament the loss of some of our favorite seafood.
Ocean acidification results from carbon dioxide in the atmosphere dissolving in seawater. The ocean is known as a “carbon sink,” or an area where excess carbon can be removed from the atmosphere, absorbing about 30% of carbon dioxide emissions. As the amount of carbon dioxide in the atmosphere increases, so does the amount dissolved in the ocean, which increases the acidity of the ocean by making carbonic acid.
In case you don’t remember from your high school chemistry class, pH is a scale of 0-14, with 7 being neutral. The ocean’s current pH is about 8.2, but as more H+ ions are released the pH is lowered and becomes more acidic. NOAA projects the pH could be as low as 7.8 in 2094. For a great animation on this chemistry and the impacts, check out NOAA’s “Ocean Acidification – The Other Carbon Dioxide Problem.”
A pH change from 8.2 to 7.8 may not seem like a huge shift, but even a small a change to the delicate balance of seawater chemistry can have a major impact by reducing the availability of dissolved calcium and carbonate, which are needed by some marine life to build and repair their shells and exoskeletons. This decrease is most pronounced in shallow areas where many shellfish make their homes. For basic, intermediate and advanced explanations of the chemistry behind these processes, visit “The Chemistry of Ocean Acidification.”
The shells of these animals could literally dissolve, including clams, oysters, scallops, lobsters and pteropods, a type of zooplankton that form part of the basis of marine food webs. With the loss of these species and impacts on food webs, there could be devastating effects on ecosystems and commercial fisheries. Additionally, it’s hard to quantify the ecosystem services that shellfish provide: as filter feeders, they help to keep the waters clean and healthy.
The National Resources Defense Council has released a study that identifies the most at-risk coastal communities and provides fact-sheets for the high-risk states where the largest impacts are expected, including my state of Connecticut. As the wife of a man who works as a shellfisherman on the side, I find this especially worrisome. If you are a fisherman, or know and love one like I do (or if you just love seafood), you know how I feel!
Fortunately, there are glimmers of hope to help curb the problems of ocean acidification and protect shelled sea creatures. In the long term, any efforts to reduce carbon emissions will also reduce ocean acidification, so if you’re already fighting the good fight against climate change then you’re already helping. We can work to reduce all other forms of pollution in the ocean like excess nutrients from runoff and wastewater, since the combination of multiple pollutants can be extra tough on marine organisms. To help the organisms protect themselves, selective breeding techniques in aquaculture can also develop shellfish with a higher tolerance for an increasingly acidic environment.
Please join Moms Clean Air Force in our fight to keep the air and water safe for our children and all living creatures, even the shellfish! View our downloadable/printable Fact Sheet on Ocean Acidification to help spread the word.
Please note: For the mermaid aficionados (like me!) who got lured in by the first sentence, check out “Mission of Mermaids: a love letter to the ocean,” a short film from Susan Rockefeller that is part of the Environmental Film Festival in the Nation’s Capitol that MCAF is sponsoring this month. It blends environmentalism with mermaids and there’s a segment about ocean acidification. The film also features Hannah Fraser, one of my favorite professional mermaid/environmental activists. I wish I had known that was a career option when I was a kid!