60% Chance Entire Great Barrier Reef Will Face "Extreme Heat Stress & Bleaching" This Austral Summer
Mass bleaching and coral death could be likely along the entire Great Barrier Reef this summer, according to a long-range forecast that coral experts say is “a wake-up call” for the Australian government. The US National Oceanographic and Atmospheric Administration (Noaa) has forecast a 60% chance that the entire Great Barrier Reef will reach alert level one, which signals extreme heat stress and bleaching are likely.
The forecast period covers November 2018 to February 2019 and the risk extends to the southern Great Barrier Reef, which escaped the mass mortality seen in the middle and northern parts of the reef in 2016 and 2017. “This is really the first warning bells going off that we are heading for an extraordinarily warm summer and there’s a very good chance that we’ll lose parts of the reef that we didn’t lose in the past couple of years,” said marine biologist Ove Hoegh-Guldberg, the director of the Global Change Institute at the University of Queensland. “These are not good predictions and this is a wake-up call.”
Hoegh-Guldberg said it was particularly worrying that the long-range forecasts were already showing high chances of bleaching and mortality before March, which is the main month of the year for bleaching events. He said if the models proved accurate it would mean the entire Great Barrier Reef would be damaged by climate change and coral populations would trend towards very low levels, affecting the reef’s tourism and fishing industries and the employment they support.
“To really have the full picture we’re going to have to wait for those projections that cover the main part of bleaching season,” he said. “Given sea temperatures usually increase as we get towards March, this is probably conservative.”
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https://www.theguardian.com/environment/2018/oct/26/great-barrier-reef-forecast-warns-entire-system-at-risk-of-bleaching-and-coral-death-this-summer