Current Global Reef Bleaching Event Longest On Record
The massive bleaching hitting the Great Barrier Reef off the coast of Australia is likely that country's "biggest ever environmental disaster," says Dr. Justin Marshall, who has studied the reef for three decades. Only 7 percent of the reef has escaped bleaching, according to researchers at the ARC Center of Excellence. Marshall, a professor at the University of Queensland, says the destructive phenomenon is happening in an area the size of Scotland.
"Before this mass bleaching started, we already were at the point of losing 50% of the coral cover on the Great Barrier Reef. This, I think, will probably take another 50% off what was left," Marshall says. Over the course of the last six months, Marshall and his colleagues with the citizen science project Coral Watch have documented the degradation of reef structures near Lizard Island, one of the worst-hit areas. They photographed the same formations of coral multiple times, showing clearly the pace of the destruction.
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This series of images taken by Coral Watch shows a close-up of healthy coral's progression through bleaching, and later covered with thick algae.
Photo (1) shows healthy coral. It's then seen bleached (2). Photo (3) shows dead coral with a film of algae, which grows thicker in photo (4).
Bleached coral near Lizard Island showing heavy algal overgrowth.
Scientists are concerned about reefs worldwide. "We are currently experiencing the longest global coral bleaching event ever observed," C. Mark Eakin, the Coral Reef Watch coordinator at the National Oceanic and Atmospheric Administration in Maryland, tells The New York Times. "We are going to lose a lot of the world's reefs during this event."
Now, Australia's summer is ending and the water is cooling down. Marshall says some of the bleached coral is beginning to recover — but much of it is dying. He says that reefs in the area where these photos were taken could see 90 percent mortality.
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http://www.npr.org/sections/thetwo-way/2016/05/14/477963623/new-photos-show-the-rapid-pace-of-great-barrier-reef-bleaching