Carbon dioxide emissions are not just warming up our atmosphere, they're also changing the chemistry of our oceans. This phenomenon is known as ocean acidification, or sometimes as global warming's "evil twin" or the "osteoporosis of the sea." Scientists have warned that it poses a serious threat to ocean life. Yet major American

news outlets covered the Kardashians over 40 times more often than ocean acidification over the past year and a half.

Rising carbon dioxide emissions have caused the oceans to become around 30 percent more acidic since the Industrial Revolution, and if we do not lower the amount of CO 2 in the atmosphere, the ocean surface could be up to 150 percent more acidic by 2100. At that level, the shells of some plankton would dissolve, large parts of the ocean would become inhospitable to coral reef growth, and the rapidity of the change could threaten much of the marine food web. According to the National Research Council, the chemical changes are taking place “at an unprecedented rate and magnitude” and are “practically irreversible on a time scale of centuries.”

Despite a boom of recent scientific research documenting this threat, there has been a blackout on the topic at most media outlets. Since the end of 2010, ABC, NBC, and Fox News have completely ignored ocean acidification, and the Los Angeles Times, USA TODAY, Wall Street Journal, MSNBC, CNN, and CBS have barely mentioned it at all.

While most coverage described the basic scientific phenomenon or listed ocean acidification as a serious environmental challenge, the Wall Street Journal dismissed the problem. All three mentions of ocean acidification from the Journal were from columns that downplayed the threat -- there was not a single straight news article interviewing scientists. One of those columns was a full article devoted to distorting and cherry-picking the science on ocean acidification. The Journal also published a letter to the editor (not counted in this study) from the Competitive Enterprise Institute's Chris Horner who summarily dismissed ocean acidification as “the latest nominee to supplant troubled CO2-warming theory.” But the threat is nothing to shake off.

Since the Industrial Revolution, global surface temperatures have increased by about 1.4 degrees Fahrenheit. But we would have warmed up more if the ocean did not absorb about 30 percent of the CO 2 we release into the atmosphere. At first scientists focused on the benefits of this absorption in reducing the amount of warming expected to result from CO 2 emissions. But more recently they have been studying how dissolved CO 2 is increasing the acidity of the ocean. These changes are happening rapidly, harming the ability of species to adapt to them. As the National Research Council explained in a comprehensive 2010 report, the ocean ecosystems on which humans rely “evolved over millennia to an aqueous environment of remarkably constant composition,” but are now facing major chemical changes due to human activities:

The chemistry of the ocean is changing at an unprecedented rate and magnitude due to anthropogenic carbon dioxide emissions; the rate of change exceeds any known to have occurred for at least the past hundreds of thousands of years. Unless anthropogenic CO 2 emissions are substantially curbed, or atmospheric CO 2 is controlled by some other means, the average pH of the ocean will continue to fall. Ocean acidification has demonstrated impacts on many marine organisms. While the ultimate consequences are still unknown, there is a risk of ecosystem changes that threaten coral reefs, fisheries, protected species, and other natural resources of value to society. [...] Organisms forming oceanic ecosystems haveevolved over millennia to an aqueous environment of remarkably constant composition. There is reason to be concerned about how they will acclimate or adapt to the changes resulting from ocean acidification--changes that are occurring very rapidly on geochemical and evolutionary timescales.

The following chart from the report shows that ocean pH remained fairly constant over hundreds of thousands of years and is projected to fall considerably during this century:

An increase in carbon dioxide directly lowers the pH levels of sea water, making it more acidic. Sea water is alkaline (basic), not acidic, but scientists use the term acidification to refer to the water becoming more acidic. Higher carbon dioxide levels reduce the amount of calcium carbonate minerals, with which many organisms form their shells and skeletons in a process called calcification. Ocean acidification will make it more difficult for many calcifying organisms like shellfish and coral to build their shells and skeletons and will cause the water to be more corrosive to some organisms' already built shells.

The sea butterfly, a snail-like type of zooplankton, could be the earliest victim of ocean acidification. As they awkwardly flap through the ocean, sea butterflies smaller than a lentil are eaten en masse by salmon and many other sea creatures. This makes them very important for the oceanic food web. But by 2050, they may not be able to form their shells in the Southern Ocean any longer. And by the end of the century, the projected acidity levels would dissolve their shells.

Coral reefs will also dramatically decline and several species of corals will face extinction if we do not reduce our carbon emissions. Coral reefs are the home to so much biodiversity that even though they make up less than 1% of the ocean, one in every four sea species depend on coral reefs.

Ocean acidification poses yet another threat to coral reefs that are already endangered due an increase in widespread coral bleaching from global warming, overfishing and agricultural runoff.

Damaging ocean life could have costly impacts for humans: one study found that coral reefs alone provide a $29.8 billion global net benefit per year from fisheries, coastal protection, tourism/recreation, and biodiversity. Coastal communities, including those in Florida and Hawaii, would be hard hit by the loss of protection from storms and tourism from scuba divers and snorkelers.

And the impacts of ocean acidification on the oceanic food web would hurt many of the fisheries that provide 1.5 billion people a significant amount of food. Just earlier this year, scientists “definitively linked an increase in ocean acidification to the collapse of oyster seed production at a commercial oyster hatchery in Oregon, where larval growth had declined to a level considered by the owners to be 'non-economically viable,'” according to an Oregon State University press release about the study. Almost 50 percent of U.S. fishery revenue comes from shellfish and crustaceans, species that may be affected by ocean acidification because they depend on calcium carbonate to make their shells:

In sum, ocean acidification is a major threat to our oceans and the millions of people who depend on them for their food and livelihoods. Yet 77 percent of Americans say they have read or heard nothing about ocean acidification, according to a 2010 survey conducted for the Yale Project on Climate Change Communication. Of the 23 percent who say that they have heard of ocean acidification, only 32 percent understand that ocean acidification is caused by carbon dioxide. In other words, less than 8 percent of Americans understand the very basics of one of the largest threats to our oceans -- and a major culprit for that ignorance is the national media.

METHODOLOGY

This Media Matters study is based on a search of Nexis and Factiva from January 1, 2011 through the morning of June 26, 2012. The search terms used for Nexis were: "(ocean! w/10 acid!) or (ocean! w/10 carbon) or (ocean! w/10 chem!)" and the equivalent search was used for the Wall Street Journal at Factiva. For the daytime programming at MSNBC and Fox News, we searched an internal database for terms such as “ocean” and “acidic.” The study included articles in all sections of the newspapers, but did not include any newswire reports that were run in the paper. A newspaper article whose focus was on ocean acidification was labeled a “full article,” and any mention less than a full article was labeled a “mention” ; a TV segment that explained ocean acidification at some length was labeled a “full segment,” and any segment that mentioned that oceans were becoming more acidic was labeled a “mention.”

The results for the Kardashians were based on a Nexis and Factiva search for “Kardashian!” and included all results. These results do not include daytime programming for Fox News and MSNBC because they are not in the Nexis database.

Jocelyn Fong created the graphics for this report.