It’s common knowledge among the scientific community that climate change will eventually acidify the oceans and turn them sour. What’s less common knowledge is when exactly it will happen.
In the tropical Pacific Ocean, however, the answers are getting a little clearer — and they’re not pretty. According to a study released by the National Oceanic and Atmospheric Administration (NOAA) and University of Washington scientists on Wednesday, the amount of carbon dioxide in the tropical Pacific has increased much faster than expected over the past 14 years, making that part of the ocean much more acidic than previously believed.
“We assume that most of the carbon dioxide increase [in the tropical Pacific] is due to anthropogenic CO2,” Adrienne Sutton, a research scientist with NOAA’s Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington, told E&E News.
In other words, scientists say their results show that much of the increase in carbon dioxide concentrations can be attributed to human-caused climate change. This is because, while the amount of CO2 in the atmosphere increases at a rate of about 2 parts per million (ppm) per year, parts of the tropical Pacific saw an increase in CO2 concentrations of up to 3.3 ppm per year. NOAA’s study monitored CO2 levels at seven buoys in the tropical Pacific, starting in 1998.
“It was a big surprise. We were not expecting to see rates that strong,” Sutton told E&E.
Though the phrase “global warming” generally evokes images of a warmer atmosphere, the phenomenon arguably has an equally large impact on our oceans. When large concentrations of CO2 are released into the atmosphere, the ocean winds up absorbing about a quarter of it, according to NOAA. The CO2, in turn, makes the ocean more acidic.
Some scientists argue that our emissions of CO2 change the chemistry of the ocean faster than it’s changed for millions of years. This, according to a Wednesday report in BBC News, promises to have a detrimental effect on coral — a vital part of the ocean ecosystem.
“We are very concerned because the baby corals find it very hard to survive in high CO2 so reefs won’t be able to repair themselves,” Katharina Fabricius from the Australian Institute of Marine Science told the BBC. “It’s very, very serious.”
Acidification also harms fish, making some lose their sense of smell and “behave recklessly in the presence of predators,” the BBC reported.
The most recent report from the U.N.’s Intergovernmental Panel On Climate Change (IPCC) said there was high confidence that climate change will exacerbate the increase of CO2 in the atmosphere, thereby causing the oceans to absorb more and become acidic.
There is also emerging evidence that the process of ocean acidification may be coming full circle, actually contributing to climate change in itself. According to an article in the journal Nature, seawater soaking in carbon dioxide will actually cause plankton to release some of its compounds back into atmosphere.