Ocean acidification is much worse than imagined, as the limestone structure that forms the foundation of Florida’s coral reefs are actually dissolving dissolving away sooner than ever expected.
According to a new study published in Global Biogeochemical Cycles, research showed the upper Florida Keys were the most impacted by the annual loss of reef during the fall and winter months. Earlier projections on ocean acidification led scientists to predict that ocean pH would not fall low enough to cause reefs to start dissolving until around 2050-2060.
“We don’t have as much time as we previously thought,” said Chris Langdon, professor of marine biology and ecology at the University of Miami Rosensteil School of Marine & Atmospheric Science and a senior author of the study. “The reefs are beginning to dissolve away.”
Langdon and his team collected water samples over two years along the Florida Reef Tract — a 124-mile-long stretch just north of Biscayne National Park to the Looe Key National Marine Sanctuary. The data serves to provide a baseline for future studies and also providing a current picture of the overall health of these reefs.
What the team uncovered was alarming, to say the least. The numbers show the loss of limestone actually exceeds the rate of growth for corals on an annual basis. If this continues, expect the reefs to begin fade away right before our eyes. Besides the loss of corals, the reduced habitat for fish and other wildlife will make a significant and negative impact on the local ecosystem. Florida Keys’ reefs alone have an estimated asset value of $7.6 billion for commercial fishing, tourism and recreation.
Why is the decline prevalent in the fall and winter? The environmental conditions for coral growth are more favorable in the spring and summer, but during the fall and winter, low light and temperature conditions along with the annual decomposition of seagrass result in a slowing, or loss of growth.
“This is one more reason why we need to get serious about reducing carbon dioxide emission sooner rather than later,” Langdon said. “The worst bleaching years on record in the Florida Keys were 2014-2015, so there’s a chance the reefs could be worse now.”
The data for the study were collected in 2009-2010. The researchers suggest that a more recent analysis should be conducted to see how the reefs are faring today.