The U.S. National Oceanic and Atmospheric Administration (NOAA) next week is conducting a new survey of the Pacific Ocean to help determine just how bad the problem of ocean acidification could be for the shellfish industry, and what can be done about it.
Ocean acidification refers to the idea that increased carbon dioxide (CO2) levels in the Earth’s atmosphere have been absorbed by ocean water, becoming carbonic acid. The stronger the acid concentration, the more difficult it is for sea life such as clams and scallops to create their protective shells.
According to Nina Bednarsek, a pteropod researcher and biological oceanographer at NOAA's Pacific Environmental Marine Laboratory, there is already evidence of pitting and weakening of snail shells, a sign of growing acid content.
“The shells are already dissolving,” she said during a press briefing announcing the new survey.
The NOAA ship Fairweather will be conducting a research cruise, starting in Seattle and traveling from off the Canadian coast down to an area just off the coast of Mexico. During the voyage, a team of scientists will study water quality and organisms such as phytoplankton at multiple locations, testing the ocean’s acidity level, known as pH. Normal water is at level 7. Scientists will be looking to see if the pH has dropped below that level, indicating a more acidic content.
This study is the second benchmark, where scientists will compare their findings to a similar study conducted in 2007, according to Brad Warren, director of the Global Ocean Health Partnership, a Seattle-based program created by the Sustainable Fisheries Partnership and the National Fisheries Conservation Center.
“Going back now to look at it again is crucial,” he said.
Richard Feely, the survey’s co-chief scientist, said the problem is a global one, but scientists believe the acidic concentration is strongest in the Pacific.
“The west coast of North America is a hotpot for CO2,” he said.
If confirmed, the scientists conducting the survey acknowledged that the problem won’t be corrected overnight. Even if human beings worldwide simultaneously switched off machines to stop producing excess CO2 forever, it might take centuries for the world’s oceans to regain their environmental balance.
But the survey will arm researchers with more data to advise shellfish growers with. Warren said experiments have already shown that changing the chemistry of a controlled environment, such as an aquaculture tank, will have a positive effect, and even in open water, small areas can be affected by using electrochemical treatments. Scientists can also use the data to help growers identify open-ocean areas where the acid content may be lower.
“We need to expand the water we know how to protect,” Warren said.