But an Australian government study released last week found that over all, last year brought “the highest sea surface temperatures across the Great Barrier Reef on record.”
Only 9 percent of the reef has avoided bleaching since 1998, Professor Hughes said, and now, the less remote, more heavily visited stretch from Cairns south is in trouble again. Water temperatures there remain so high that another round of mass bleaching is underway, the Great Barrier Reef Marine Park Authority confirmed last week.
Professor Hughes said he hoped the die-off this time would not be as serious as last year’s, but “back-to-back bleaching is unheard-of in Australia.” The central and southern part of the reef had already been badly damaged by human activities like dredging and pollution.
The Australian government has tried to combat these local threats with its Reef 2050 plan, restricting port development, dredging and agricultural runoff, among other risks. But Professor Hughes’s research found that, given the high temperatures, these national efforts to improve water quality were not enough.
“The reefs in muddy water were just as fried as those in pristine water,” Professor Hughes said. “That’s not good news in terms of what you can do locally to prevent bleaching — the answer to that is not very much at all. You have to address climate change directly.”
With the election of Donald J. Trump as the American president, a recent global deal to tackle the problem, known as the Paris Agreement, seems to be in peril. Australia’s conservative government also continues to support fossil fuel development, including what many scientists and conservationists see as the reef’s most immediate threat — a proposed coal mine, expected to be among the world’s largest, to be built inland from the reef by the Adani Group, a conglomerate based in India.
“The fact is, Australia is the largest coal exporter in the world, and the last thing we should be doing to our greatest national asset is making the situation worse,” said Imogen Zethoven, campaign director for the Australian Marine Conservation Society.
Australia relies on the Great Barrier Reef for about 70,000 jobs and billions of dollars annually in tourism revenue, and it is not yet clear how that economy will be affected by the reef’s deterioration. Even in hard-hit areas, large patches of the Great Barrier Reef survived, and guides will most likely take tourists there, avoiding the dead zones.
The global reef crisis does not necessarily mean extinction for coral species. The corals may save themselves, as many other creatures are attempting to do, by moving toward the poles as the Earth warms, establishing new reefs in cooler water.
But the changes humans are causing are so rapid, by geological standards, that it is not entirely clear that coral species will be able to keep up. And even if the corals do survive, that does not mean individual reefs will continue to thrive where they do now.Continue reading the main story
Tim Flannery says preserving the Great Barrier Reef from coral bleaching linked to climate change should be a central issue in the federal election campaign.
Flannery, a scientist and member of the Climate Council, said the lack of attention paid to climate change so far in the eight-week campaign was “staggering”.
“This needs to be the reef election,” he told Guardian Australia. “This is the last moment I think that we can realistically expect that we can enact some policies … to close down coal-fired power stations and save the reef.
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“Other issues are still going to be there in another four years. This one won’t.”
A study in April found that almost 93% of the Great Barrier Reef had been affected by global bleaching, part of a global coral bleaching event that scientists say was caused partly by El Niño and partly by background global warming.
The aerial survey, conducted by James Cook University, found the bleaching was most severe in reefs north of Port Douglas, where about 81% of reefs were assessed as having severe bleaching. Prof Terry Hughes, head of the National Coal Bleaching Taskforce, told Guardian Australia last month that the mortality rate in coral reefs in that area was already at more than 50%.
Hughes said it was five times worse than the last two bleaching events, in 1998 and 2002, when 40% of the reef escaped bleaching.
Coral bleaching has also been recorded in Western Australia’s Kimberley region, where between 60-90% of some reefs are reported to be bleached.
Flannery spoke to Guardian Australia on Tuesday, soon after returning from the Kimberley. He said the bleaching he witnessed was “terrible”, adding “and these are the corals that are supposed to be the most resilient due to the high tidal difference”.
“I just find the lack of focus on this is astounding,” he said. “The whole ecosystem is now falling apart but you look at our election debate and you would think everything was fine – the only problems we had were employment, or industrial relations, or jobs and growth. I am astounded.”
Labor is campaigning on two major climate change policies, including a promise to increase Australia’s renewable energy target to 50% of electricity generated by 2030 and introduce a $355.9m dual emissions trading scheme.
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The Greens do have a policy on saving the reef, which includes banning offshore dumping, halting the proposed expansion of the Abbot Point coal port, banning new coal and coal seam gas projects, and transitioning to 100% renewables.
The current renewable energy target, which the Coalition supports, is to have 23% renewables by 2020. That target comes under the umbrella of the Coalition’s Direct Action policy, which includes the $2.5bn Emissions Reduction Fund (ERF).
The environment minister, Greg Hunt, last week released modelling that said the ERF and so-called safeguards mechanism could achieve half the emissions reductions required to meet the government’s target of cutting emissions by 26% to 28% by 2030.
However the authors of the report told Guardian Australia that doing so would require either a significant increase in funding or a strengthening of the safeguard mechanism to mimic an emissions trading scheme, which Malcolm Turnbull, who lost the Liberal leadership in 2009 because of his commitment to implementing an emissions trading scheme, has said he would not introduce.
Additional reporting by Guardian Australia political editor Lenore Taylor