In the most extreme mass bleaching event ever to have hit the Great Barrier Reef, scientists from James Cook University have confirmed that over a third of corals in the northern and central regions of the World Heritage Site are dead or dying. This worrying announcement follows the news that the Australian government has had all mentions of the Great Barrier Reef removed from a UN report looking into the impacts of climate change on tourism.

“We found, on average, that 35 percent of the corals are now dead or dying on 84 reefs that we surveyed along the northern and central sections of the Great Barrier Reef, between Townsville and Papua New Guinea,” explains Professor Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, in a statement. “Some reefs are in much better shape, especially from Cairns southwards, where the average mortality is estimated at only 5 percent.”

^{Before and after photo of mature staghorn coral at Lizard Island, Great Barrier Reef. The coral was bleached in February 2016, and then dead and overgrown by algae in April 2016. ARC Centre of Excellence for Coral Reef Studies}

While earlier studies found that over 90 percent of some parts of the reef were bleached, and suggested that up to 50 percent of some northern regions were dead, this new report shows that over a third of the coral is dead or dying over the majority of the reef. When corals become bleached, it does not necessarily mean that they will die; if the water temperature returns to prior conditions, then the tiny animals can recapture the algae and recover. But clearly this has not happened quickly enough for a large portion of the reef system in northern Australia.

The news comes just a few days after The Guardian Australia exposed that the Australian government lobbied the United Nations to remove all mention of the country in the final version of a major UN report on climate change. The report, titled “World Heritage and Tourism in a Changing Climate,” was originally meant to include an entire chapter on the Great Barrier Reef, as the impacts of the warming waters – driven by climate change and the latest El Nino – have taken their toll, but Australia objected under claims that mentioning the reef would harm tourism to the region. The impact of climate change on another Australia nation park, Kakadu, and on the forests of Tasmania were also scrubbed from the report.

^{Before and after photo of mature staghorn corals taken in 1996 at low tide, two years before the 1998 bleaching event, and again 20 years later in 2016. ARC Centre of Excellence for Coral Reef Studies}

This comes following the government's successful lobbying of Unesco to omit the Great Barrier Reef from their list of “World Heritage Sites in Danger.” The environment department have claimed that by including the reef in the UN report under the title “Destinations at Risk,” it had “the potential to cause considerable confusion.” It comes in a long string of moves by the Australian government that have been heavily criticized by environmental groups, including the approval of a coal port on the Great Barrier Reef, the sacking of 100 government climate scientists, and proposals to open up Tasmanian forests to logging.

It is thought that the southern regions of the reef survived the heavy bleaching due to a cyclone that swept the area, cooling the water. This is the third bleaching event to have hit in 18 years, and is so severe it could take a decade to recover. But with the planet continuing to warm, it is predicted that events like these will happen on a regular occurrence, and that the reef simply will not have that time.