By Sebastian Modak. Photos: Getty.
As summer in the Southern Hemisphere came to a close last year, alarming data out of research institutions in Australia showed that a large stretch of the 1,491-mile Great Barrier Reef was in danger of dying due to coral bleaching, a phenomenon caused by pollutants and rising sea temperatures. It was a worrying trend, but not unprecedented. After all, the reef had experienced (and recovered from) coral bleaching events in the past—most recently, in 1998 and 2002. Today, however, the ARC Centre of Excellence for Coral Reef Studies released the results of its aerial surveys of the reef, conducted over the entire length, and it's not pretty.
The study reveals that the reef has experienced massive coral bleaching for the second time in just twelve months. Coral bleaching occurs when the tiny algae that give corals their energy and brilliant color are expelled from the living creatures, leaving nothing behind but a bone-white skeleton. Given the right conditions—and at least 10 years—coral reefs can recover from coral bleaching events, if temperatures are stabilized or environmental stressors like pollutants are removed. But when the events occur two years in a row, corals, and the organisms that depend on them, can die. Even more worrisome than these events happening back to back is that while 2016's event most affected the remote northern stretch of the reef—a region that is less visited by tourists—the aerial surveys show that it has now spread to the middle section of the reef, showing that the effects of warming waters are not limited to single sections of the reef.
"The combined impact of this back-to-back bleaching stretches for 1,500 km (900 miles), leaving only the southern third unscathed,” Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies, said in a statement released today.
While in 2016, scientists were quick to debunk the obituaries that spread on social media mourning the death of the reef, claiming instead that we could save reefs around the world by slowing climate change, the future for bleached sections of the Great Barrier Reef now seems decidedly grim. “It takes at least a decade for a full recovery of even the fastest growing corals, so mass bleaching events 12 months apart offers zero prospect of recovery for reefs that were damaged in 2016,” said James Kerry, who along with Hughes, undertook the aerial surveys in 2016 and 2017.
The severity of 2016's coral bleaching event was compounded by El Niño, a meteorological event that leads to warmer waters, but the fact that this year's event occurred without that extra complication, puts the relatively unscathed southern stretch of the reef now in great danger. If you ask the researchers, the culprit is clear. “Clearly the reef is struggling with multiple impacts,” said Hughes. “Without a doubt the most pressing of these is global warming. As temperatures continue to rise the corals will experience more and more of these events: 1-degree Celsius of warming so far has already caused four events in the past 19 years.”
The Great Barrier Reef attracts more than 2 million visitors a year who head out on expeditions to see the giant ecosystem through the lens of scuba and snorkeling goggles, and generates around $4 billion a year in tourism revenue. Tourists to the reef are being reminded that while visiting is still encouraged, there are precautions one can take to limit the detrimental effect they can have on the reef: For example, don't, under any circumstances, step on live coral and opt for a wetsuit or reef-safe sunscreen. While the opportunity to see the reef as it was even 10 years ago is ending, if not already gone, as Hughes points out, the threat is an existential one, beyond just its ramifications for travelers. "Ultimately, we need to cut carbon emissions, and the window to do so is rapidly closing,” he says.
This story originally appeared on Conde Nast Traveler.
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