Researchers studying Australia’s Great Barrier Reef have discovered that more than two-thirds of the coral has been devastated by bleaching.
This isn’t a huge surprise. For years, scientists have been beating the climate change drum, watching as massive sections of reefs all over the world die. Recently it was revealed that Japan’s largest coral reef is around 70% dead, and the Great Barrier Reef has been the subject of much concern as the oceans warm too quickly. After three years straight of record bleaching events, the news broke that some 65% of the coral of the northern reef is dead, and the coming months were expected to be even worse. Turns out they were.
Coral bleaching isn’t all that strange. It happens regularly, and given time and a return to regular ocean temperatures, the corals recover. That, however, requires a return to regular ocean temperatures. When sea temperature increase, the algae inside the coral (that’s what gives it all those beautiful colors) gets spat out, returning when temperatures drop. If they don’t return quickly enough, the coral dies. Widespread bleaching was recorded at the Great Barrier Reef in 2016 and this year. Before 2016, only two bleaching events occurred in two decades–and yes, global warming has been linked directly to it.
“This is the fourth time the Great Barrier Reef has bleached severely – in 1998, 2002, 2016, and now in 2017,” Dr. James Kerry, from James Cook University, said to CNN. “Bleached corals are not necessarily dead corals, but in the severe central region, we anticipate high levels of coral loss. 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.”
When researchers flew over the reef for an aerial survey, they were shocked. Around 900 miles of the UNESCO World Heritage Site have been ravaged by bleaching. Up until now, most of the damage was limited to the northern part of the reef. Now, however, the middle of the reef is in the same boat. The bottom third, where the water is cooler, is still hanging on.
“The central section of the reef is now displaying the same extent of bleaching as in the north,” Kerry continued. “Going over those reefs this year, you can tell how low the coral cover was. It was shocking to see the fallout from last year’s event.”
The Australian government is making an effort–the reef is responsible for around $3.7 billion annual tourism dollars–but it doesn’t seem to be having much effect. “The Australian government has launched an unprecedented effort to invest more than A$2 billion ($1.5 billion)… in a Reef 2050 plan, which we’re 18 months into,” said Josh Frydenberg, Australia’s Minister for the Environment and Energy.
