Research: 20 Carbon Majors Responsible for More Than 20 Percent of Ocean Acidification

By Karen Savage

The 20 largest fossil fuel companies are responsible for more than one-fifth of the increase in ocean acidification between 1880 and 2015, according to newly released research.

Several companies facing climate liability suits in the U.S.—including Chevron, Exxon, BP, Shell, ConocoPhillips and Total—are among the companies most responsible, according to the data. The peer-reviewed research was released in the scientific journal Environmental Research Letters on Wednesday.

“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,” Rachel Licker, lead study author and senior climate scientist for the Union of Concerned Scientists (UCS) said.

“Scientists can now quantify how much more acidic the ocean has become as a result of each fossil fuel company’s products.”

The oceans have absorbed a vast amount of the excess CO2 in the atmosphere, overwhelmingly produced by the burning of fossil fuels. That CO2 mixes with seawater to create carbonic acid, which raises the pH level of the water, making it more acidic.

The fossil fuel industry has been aware that its products contributed to rising atmospheric CO2 levels since at least the mid-1960s, according to the companies’ own documents that have been uncovered in the last several years. Many companies were warned of these risks by their own internal scientists. Once these risks became more widely known, fossil fuel companies launched a multimillion-dollar disinformation campaign to convince the public that climate science was too uncertain to warrant action.

Despite overwhelming scientific consensus that climate change is caused by the burning of their products, many companies are planning to increase production through 2030. Shell expects to increase oil and gas production by 38 percent, Exxon is expected to increase production by 35 percent, BP is planning a 20 percent increase and Total is planning on a 12 percent increase.

“By putting a number on fossil fuel company contributions to disruptive ocean acidification, our study can inform decisions about their responsibilities for damages that could have—and should have—been avoided,” said Peter Frumhoff, report co-author and director of science and policy at UCS.

The study’s authors focused on the 88 largest gas, oil and coal producers and cement manufacturers and calculated the amount of ocean acidification that occurred as a result of emissions released during fossil fuel extraction, production and use. Using a dataset developed by the Climate Accountability Institute, the researchers adapted their methodology from a 2017 study, which linked increases in global temperatures and sea level rise to specific fossil fuel companies.

Because ocean acidification—and its impacts—are not uniform across the globe, the researchers used a 3-D model to map the differences.  The maps revealed five regions where ocean acidification and related changes in ocean chemistry are affecting nearby communities whose livelihoods depend on marine life.

“We take previous work that ties carbon emissions to the largest industrial carbon producers and attributes climate impacts to those emissions a stop further, by beginning to demonstrate the potential associated losses and damages from ocean acidification,” the authors wrote.

The newly released study is part of a new avenue of research connecting specific climate impacts to the actions of individual companies.

“Such work would continue to advance considerations of responsibility for the changes, impacts, and risks and could be extended into a variety of climate domains—from changes in temperature to sea level rise,” the authors wrote.

The world’s oceans have been hard-hit by climate change. Because their waters absorb carbon dioxide, as emissions have risen, so has acidification. Since 1880, the ocean’s surface water acidity has increased more than 25 percent.

“Ocean acidification makes it more difficult for many marine organisms to construct their shells and skeletons,” Scott Doney, study co-author and the Kington professor of environmental change at the University of Virginia said. “The organisms at risk from acidification form the foundation of the marine ecosystem food chain—including some types of plankton, algae, shellfish, and coral that may struggle to grow and survive in a future warmer, more acidic ocean.”

Among the regions disproportionately affected are the Bering Sea and Gulf of Alaska, where more than 53,000 local residents rely on fishing for their livelihood and the California Current, which runs along the west coast.

West coast fisheries are already feeling the effects of climate change. For four consecutive years, the crab fishery has been forced to close by algae blooms, which are caused by warming waters.

The Pacific Coast Federation of Fishermen’s Associations (PCFFA), the region’s largest commercial fishing association, last year filed a lawsuit against 30 fossil fuel companies, including Chevron, Exxon and Shell.  The PCFFA alleges the companies were warned decades ago that that rising greenhouse gas emissions could result in the possibility of “wiping out the world’s present commercial fisheries.” 

The association’s members, which include crab harvesters, onshore crab processors and wholesalers, are still suffering severe financial hardships due to the closures, the PCFFA said in the complaint. It is seeking to hold the companies accountable for the losses. 

The new research will likely bolster the PCFFA’s lawsuit as well as climate liability suits filed by dozens of municipalities across the nation seeking to hold the fossil fuel companies accountable for their role in climate change.

“As impacts worsen and become more costly, frontline communities and affected industries are now calling on fossil fuel companies to take responsibility for their outsized contribution to the problem,” Frumhoff said.

“Companies could have acted responsibly to inform the public about risks and taken actions to reduce emissions. They chose instead to disinform and delay.”