Our oceans are acidifying at a rate not seen in 66 million years. They’re now 26 percent more acidic since 1880, which is profoundly changing ecosystems and impacting the fisheries that rely on them, all around the world.
A new study shows exactly who is to blame. Just twenty companies caused over one fifth of the ocean acidification that occurred since 1965. This is the time period after these companies understood the dire impacts of their industry; they include Exxon, Chevron, BP, Shell and Saudi Aramco.
In fact, climate scientist Rachel Licker from the Union of Concerned Scientists (UCS) and colleagues have shown that the largest 88 gas, oil and coal producers and cement manufacturers are responsible for more than half of the ocean acidification since 1880.
“We’ve known for several decades that burning fossil fuels is by far the largest driver of ocean acidification, but we weren’t able to track how much any one fossil fuel company contributed to the problem, and in what way,” said Licker.
“Scientists can now quantify how much more acidic the ocean has become as a result of each fossil fuel company’s products.”
Ocean acidification occurs when excess CO2 dissolves into seawater, producing a series of chemical reactions that lead to more hydrogen ions, increasing the water’s acidity. This altered ocean chemistry has already led to a 10 percent decrease in carbonate concentrations since industrialisation.
Less carbonate means it’s harder for calcium carbonate to form; this is a vital molecule for most marine animals because it is part of their shells and exoskeletons. And if the concentration of carbonate drops too low, calcium carbonate dissolves.