Phil Walter/Getty Images News/Getty Images

Is The Great Barrier Reef Dying?

Last October, Outside Magazine posted an unusual obituary, mourning the death of the Great Barrier Reef. While tongue-in-cheek, some readers took it a little too seriously, with many believing the over 1,400-mile long coral reef system off of Australia's northeastern coast was dead and gone. Scientists, environmentalists, and researchers cried foul, but the much-troubled reef seemed to finally get the attention it has needed. On Monday, researchers revealed that two-thirds of the reef have undergone extensive "bleaching," a process that could kill the coral for good. Is the Great Barrier Reef dying? While bleached reefs don't mean the Great Barrier Reef has died, bleaching does sound a death knell echoing the massive effects of climate change in the region.

Coral reef bleaching, particularly in the Great Barrier Reef, is nothing new. However, what makes the latest observations so concerning is just how widespread the bleaching has become in the waters of Australia's Queensland coast — and how quickly. The Australian Research Council’s Centre of Excellence for Coral Reef Studies conducted aerial surveys, revealing two that mass bleaching events affecting the Great Barrier Reef have occurred so closely together between 2016 and 2017 that more than 900 miles of the reef are currently bleached. The reef may not be dead, but it's only a matter of time given the extent to which climate change has caused the reef to bleach.

What Is Coral Reef Bleaching?

While coral may look like the ocean's quirky home decor, coral reefs are actually incredibly diverse underwater ecosystems. Coral have a symbiotic relationship with algae: The coral provides protection for the algae while the algae supply the coral with nutrients. It's that algae that give coral its many vibrant colors and hues. Bleaching occurs when coral expel the algae from its formations. In the Great Barrier Reef, there are two major causes of coral reef bleaching: agricultural runoff and rising ocean temperatures.

The Surest Sign Of Climate Change

While the 2016 Great Barrier Reef bleaching event was caused by El Niño, a naturally occurring weather phenomenon, the 2017 bleaching event points to rising sea temperatures separate from El Niño, as the bleaching has occurred after El Niño passed. Speaking to The Guardian, researcher Terry Hughes says the damage to the reef is extensive:

The significance of bleaching this year is that it’s back to back, so there’s been zero time for recovery. It’s too early yet to tell what the full death toll will be from this year’s bleaching, but clearly it will extend 500km south of last year’s bleaching.

What's The Big Deal?

If bleaching continues, the beautiful array of colors for which the reef is known would vanish, and eventually, so would the beach: Loss of the Great Barrier Reef would result in massive beach erosion along the Queensland coast. The biggest and most immediate impact if the Great Barrier Reef died would be to Australia's tourism industry. There were more than 2.62 million visitors to the Great Barrier Reef in 2016 alone, according to the Great Barrier Reef Marine Park Authority. The Australian government notes that Great Barrier Reef tourism accounts for as much as $4 billion in revenue annually.

But it's not just about the bottom line for Australia: It's about the health of the planet, too. Coral reef bleaching is happening across the world's oceans as a direct result of both rising temperatures and acidity. Coral reef bleaching can actually be seen from space, a stark sign that climate change is wreaking havoc on nature's many ecosystems — including our oceans. While the Great Barrier Reef has bounced back from bleaching events before, this one-two punch between last year and this year could prove to be too much for the 500,000-year-old living ecosystem to handle.