OCEAN ACIDIFICATION

OCEAN ACIDIFICATION When we spew carbon dioxide into our air, it eventually ends up in our oceans, too — absorbed to the tune of about 22 million tons per day. This results in global warming’s evil twin: ocean acidification. As oceans absorb carbon dioxide, or CO2, seawater chemistry changes and the water becomes more acidic. According to scientists, the oceans have become about 30 percent more acidic due to human CO2 emissions — and this spells trouble for ocean life. First of all, ocean acidification depletes seawater of the compounds that organisms need to build shells and skeletons, impairing the ability of corals, crabs, seastars, sea urchins, plankton and other marine creatures to build the protective armor they need to survive. To make matters worse, fish and other ocean organisms may be adversely affected from the rise in acidity in their ocean habitat. Fish are common ocean prey, and plankton are at the base of the ocean food chain, so when these animals suffer, so do the countless animals that eat them. Ocean acidification could disrupt the entire marine ecosystem. Since ocean acidification is one of the gravest threats to marine biodiversity, the Center is tackling it head on, and has launched an initiative to protect our oceans from CO2 pollution. The Clean Water Act is the nation’s strongest law protecting water quality, and we’re using the tools provided by this law to stop pollution causing ocean acidification as well as to improve water-quality standards and monitoring for pH. In 2007, we petitioned eight coastal states to declare ocean waters impaired under the Clean Water Act due to ocean acidification, which would require those states to limit CO2 pollution entering waters under their jurisdiction, helping to reduce the devastating effects of ocean acidification. The same year, we also petitioned the U.S. Environmental Protection Agency to impose stricter pH standards for ocean water quality and publish guidance to help states protect U.S. waters from acidification. Finally, in spring 2009, the agency for the first time invoked the Clean Water Act to address the acidification crisis, calling for data to use for evaluating water-quality criteria under the Act. But when it failed to take action against ocean acidification in Washington state waters — which are in violation of the state’s already lax water-quality standard for pH — we were forced to sue the agency in spring 2009. Thanks to our landmark lawsuit, the next year the EPA recommended that coastal states begin addressing ocean acidification under the Clean Water Act. We also advocate for the protection of species affected by ocean acidification, most notably elkhorn coral and staghorn coral, which make up much of the rapidly declining coral reefs of Florida and the Caribbean. These corals were listed as endangered under the Endangered Species Act in 2006 as a result of a Center petition, and in September 2007, we sued the National Marine Fisheries Service to speed designation of critical habitat. While elkhorn and staghorn corals are the first species to be listed because of vulnerability to global warming, they unfortunately won’t be the last. The Center will continue to defend our ocean’s life and fight to curb the pollution that threatens it.

Photo © Paul Townend