
Photo by Enric Sala
Coral reefs are vanishing faster than rain forests. Why? Every day for the last decade, our ocean has absorbed roughly 22 million tons of carbon dioxide (CO2). This greenhouse gas, which humans generate by activities such as using electricity, developing land and driving cars, dissolves in the water. But it doesn’t vanish. It turns into carbonic acid, which alters the ancient chemistry of our oceans. It also causes the skeletons of corals to corrode.
Coral, the often misunderstood animals, not plants, fuse their skeletons into reefs that make up a kaleidoscopic 1 percent of the ocean floor. These reefs are the largest structure on the planet created by animals, and support a fourth of all marine life by serving as spawning and feeding grounds. Coral reefs also boost tourism — about $364 million each year in Hawaii alone — and act as natural coastal barriers during storms.
Scientists predict that up to one-third of corals may vanish in the next 30 years.
Though ocean acidification isn’t new, scientists claim that it’s happening at a rate 10 times faster than it did 50 million years ago. And the effects of CO2 are just beginning to be felt.
“Whenever CO2 levels change rapidly in the geologic history of our planet, there have been major extinction events. We are currently in the middle of a major extinction event,” said George Waldbusser of Oregon State University, who is identifying hot spots.
The Coral Triangle, which includes the waters of Indonesia, Malaysia and the Philippines, may be especially susceptible to acidification.
“Once the chemistry of the ocean changes, turning back the hands of time will be next to impossible,” said senior scientist Lisa Suatoni of the Natural Resources Defense Council. She and other scientists believe the combined stresses from ocean acidification and climate change could cause the extinction of corals by the end of the century.
As the ocean continues to absorb CO2, the long-term health of the planet remains uncertain. If the ocean’s capacity to act as a greenhouse gas storehouse diminishes over time, leaving more carbon dioxide in the atmosphere, it’s not just coral and other marine life that people will be worrying about.
S. Ingber, Share America, 30 September 2014. Article.