Souring Seas: What Ocean Acidification Might Mean for New England
The Gulf of Maine could be the “canary in the coal mine” for acidifying oceans, according to one presenter at an event designed to get people in New England thinking about how souring seas might affect them.
In ocean acidification, sometimes called the evil twin of climate change, pH drops as the seas absorb about a quarter of the carbon dioxide we’re pumping into the atmosphere. Scientists say our oceans have become about 25 percent more acidic over the last 150 years or so, and will become far more acidic by the end of the century. A recent study estimated that this could cause a trillion dollars in economic loss annually by 2100, as acidic oceans deplete calcifying organisms such as corals and clams and some plankton at the base of the ocean food web.
Some calcifying organisms known as scallops make New Bedford the highest-dollar seafood port in America, so it was a natural place for the Woods Hole Research Center to hold an event on the topic. The potential economic impact of acidification is not lost on folks there. Three past and current New Bedford mayors attended, as did a handful of state legislators, fisheries management officials, and representatives of the lobster and shellfish industries.
Some leading scientists offered an overview of what we do and don’t know about the problem, with examples specific to New England’s waters. One key point was that acidity can vary greatly with seasonal changes and location. Dr. Scott Doney, who directs the ocean and climate change programs at the Woods Hole Oceanographic Institution, emphasized the effect nutrient runoff has on coastal waters.
Dr. Cynthia Pilskaln of UMass Dartmouth raised the point about the “canary in a coal mine.” Her work monitoring changes in the Gulf of Maine shows that the area has little ability to buffer against the effects of acidification. She warned that some major species of plankton may be unable to form shells if ocean pH continues to drop as predicted through 2100. The Gulf of Maine has already seen a decline in primary productivity of its plankton communities but Pilskaln says it’s not yet clear what that might mean for the animals higher in the food web.
Work by Dr. Justin Ries of Northeastern Univ. shows how complicated it can be to predict how different marine organisms respond. While some shell forming creatures suffer as acidity increases, a few species benefit in the short term exposure to acidity before eventually numbers fall off as acidity increases.
Those in the affected industries face a lot of uncertainty. And the delay between emissions of CO2 and effects on the sea makes it hard for those concerned with day-to-day challenges of fishing and aquaculture to understand the relevance to their lives.
The Woods Hole Research Center’s event is a good start at connecting information with the people who need it. Material from the conference presenters is available here.