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Coral Bleaching in the Great Barrier Reef Sure Looks a Lot Like Climate Change

Coral die offs have become all too common. As Dr. Tyrone Ridgway explained, "There's been bleaching in Hawaii this year, Caledonia, and now Australia."
All Photos by XL Catlin Seaview Survey

Here are two things that are not a coincidence: February was the hottest month in global history. And on March 21, Greg Hunt, the Australian environment minister, announced the threat of coral bleaching in the Great Barrier Reef Marine Park would be increased to the highest level—"severe."

Why is this no coincidence? Well, over the past two weeks, maximum temperatures were driven two degrees higher across almost all of tropical Australia. In Northern Queensland, clear skies and calm conditions meant coral cooked in clear, still waters, killing off large patches of reef around Lizard Island.


Bleaching of the reef around Lizard Island. All photos by XL Catlin Seaview Survey

Coral bleaching happens when coral—stressed by excess heat, light, or pollution—expels all of the beneficial algae living inside it, turning reefs sickly pale. Bleaching can kill coral, damaging these delicately balanced ecosystems to the point they can't be repaired, and it also makes for a pretty depressing snorkeling experience.

In response to the coral bleaching crisis, the government has announced a new survey of 40 sites in the 1,400 mile-long reef's far northern section to take place this September. The new data will be compared with that collected in 2012 and 2014.

Dr. Tyrone Ridgway is the manager of the Healthy Oceans Program at the University of Queensland. He has worked with the Great Barrier Reef Marine Park Authority and been involved in the project management of the Climate Change Action Plan, as well as overseeing the Reef Health Impact Survey and BleachWatch programs. Speaking to VICE, he emphasizes that its current situation is far from unique. In fact, it's symptomatic of a worldwide problem.

"Things are not going great," he said. "There's been bleaching in Hawaii this year, Caledonia, and now in Australia."

Coral bleaching in Queensland's north is the worst it has been in fifteen years. Ridgway says that sea temperatures in the far northern section of the Great Barrier Reef have been steadily climbing in the past four to six weeks, with the water averaging one to two degrees warmer than usual.


As it stands, scientists are unsure if the worst is over. "According to our predictions, sea temperatures will be quite a lot warmer than they should be in the weeks ahead. If weather conditions remain calm, that will exacerbate the problem. But if there's storm activity, that will help the temperatures drop off slightly," he says.

The prognosis does seem fairly bleak. "But it's definitely not too late to do something, or for governments to take action rather than just talk about taking action."

Greg Hunt's proposed surveys, he says, are useful to an extent. They'll help us compare old and new data, but they won't bring the coral back. "What we're seeing is an increase in sea temperatures due to climate change, and all over the world more of these extreme weather events are happening. They'll keep on happening.

"What we're really talking about here is needing carbon reduction and climate change initiatives. If the temperature goes back to normal, there's a good chance the coral will recover. But we need to reduce carbon emissions. Frankly, if the coral is going to have any chance, temperatures have to be kept between 1.5 [34.7 F] and 2 degrees celsius [35.6 F]. Ideally 1.5 degrees."

Of course, coral bleaching isn't the only issue facing by the Great Barrier Reef. Our relationship with one of the country's most well-known tourist spots is abusive at best. But while dredging the hell out of it isn't exactly an ideal way to treat a pristine natural marine park, Ridgway reckons we shouldn't become too distracted by what are ultimately small scale problems. "To be honest, the reef is massive and dredging is actually only an isolated thing that will happen in a small location over a short period of time."

Actually, there are lots of small things we're doing to damage the Great Barrier Reef. Coating it in toxic sunscreen, for example. But as far as the long term future of all that coral is concerned, as a marine scientist Ridgway attests that we've definitely got bigger fish to fry.

"We should really be worried about is these mass temperature rises over vast spatial scales," he reiterated. "That's the focus."

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