Dissolving the Seafloor Because of Climate Change

Ocean acidification is setting off a feedback loop that’s dissolving the seafloor.

Carbon dioxide emissions are acidifying the ocean so quickly the seafloor is dissolving. A new study details how this sets off a feedback loop that acidifies the ocean even more rapidly, and it is already killing off foundational marine life species such as coral and threatening the balance of all ocean ecosystems on which we depend.

Foundational species in the marine food chain, such as coral, thrive within a particular range of pH levels. When the pH levels change for a long period of time, these species and all ocean life that depends on them can’t survive. 96 percent of ocean life was extinct the last time oceans were as acidic as they are now.

One positive sign is that calcium carbonate is still dissolving carbon dioxide in the water, so there is still a process fighting against ocean acidification. But the rate we’re emitting carbon dioxide is far greater than the rate at which carbon dioxide gets taken up by calcium carbonate on the ocean floor.

According to the study, the seafloor of the north Atlantic, along Europe, has dissolved at the most severe locations seen 40 to 100 percent. Until now there’s been no concerted assessment of carbon dioxide-driven dissolution of the seafloor.

In order to understand the full extent of how we’ve affected the chemistry of the ocean, scientists will need to conduct studies of the seafloor with mathematical modeling and real world sampling. We are already seeing the impact of our actions. Based on the most optimistic forecasts for ocean acidification, which assume fundamentally restructure society in order to mitigate climate change, 90 percent of coral reef communities will bleach in the next 80 years.

 

 

Photo: You are what you eat: Diatoms" by sirkles is licensed under CC BY-SA 3.0