Exactly what is ocean acidification?

Our oceans absorb about a quarter of the carbon dioxide that humans produce by burning fossil fuels each year, and that's changing their basic chemistry. This is particularly bad for creatures with calcium carbonate in their shells or skeletons, like mollusks, crabs, and corals. Acidic water makes it harder for them to grow those shells, so many of them are going to have a hard time surviving as our seas change.

Even if you live in the ocean and don't have a shell, bad things could be in store for you. Laboratory studies have shown that increased acidity makes it more difficult for clownfish (a.k.a. Nemo) to sense predators and for sharks to hunt their prey. (NRDC's onEarth magazine wrote about this.) Scientists estimate that carbon pollution is causing oceans to acidify faster than they have in 300 million years.

OK, so Nemo and some shellfish are having a bad day. But is ocean acidification bad for people?

Absolutely. Communities whose livelihoods depend on fishing are already being affected, and more will be. Significant portions of our economy rely on the ocean's bounty in one way or another.





A Scalloper in Martha's Vineyard Massacusetts Office of Travel and Tourism/Flickr

Which areas of the United States are most vulnerable to acidification?

Some of my colleagues and I recently completed a collaborative study assessing which coastal areas are most at risk. In the Gulf of Mexico, nutrient pollution from runoff is combining with carbon pollution in the atmosphere and causing waters to acidify much more quickly than scientists expected, putting the $10 billion fishing industry there at risk. And in Alaska, where half of the seafood caught in this country comes from, rapidly acidifying cold water is endangering 70,000 jobs.

So do we have to learn to live without oysters? Or are there things we can do about the problem?

Actually, we can tackle ocean acidification on multiple fronts. We need to reduce carbon pollution by burning fewer fossil fuels and using more renewable energy. At NRDC, we think carbon-pollution standards that reduce power plant emissions and stronger fuel-economy standards for vehicles can help with that.

We also need to prepare for these changes in our oceans, particularly in vulnerable industries. Some West Coast oyster hatcheries have addressed their ocean-acidification crisis by monitoring the surrounding waters. When harmful acidic water upwells on the coast, they shut off their intake valves, since baby oysters are especially vulnerable to acidity. They've also changed their lab procedures to buffer water against the acidity rise so that vulnerable larvae aren’t exposed.

​On an individual level, you can contact policy makers and let them know you want them to devote money to researching and monitoring ocean acidification. Since we know the problem is caused by carbon emissions, you can also work to reduce your personal carbon footprint. Nitrogen pollution from agricultural runoff can exacerbate the problem, so using organic gardening practices and purchasing sustainably grown food whenever possible are good ways to start.