(COMMON DREAMS) Jessica Corbett, October 26, 2018 — Delivering yet another “wake-up call” after recent studies have shown that heat stress from anthropogenic global warming has killed half of the Great Barrier Reef’s corals since 2016, a new analysis from U.S. scientists warns that the entirety of world’s largest coral system is at risk of bleaching and death as Australia enters it summer months.
“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.”
—Ove Hoegh-Guldberg, Global Change Institute
The forecast from U.S. National Oceanographic and Atmospheric Administration (NOAA) for November 2018 to February 2019 indicates that the whole reef has a 60 percent chance of reaching “alert level one,” under which bleaching is “likely.”
When coral is exposed to warm water or pollution, it expels the algae living in its tissues—its main source of food—and turns completely white. Although bleached coral is still alive, the reactionmakes it more susceptible to disease and death.
“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,” marine biologist Ove Hoegh-Guldberg, the director of the Global Change Institute at the University of Queensland in Australia, told the Guardian. “These are not good predictions and this is a wake-up call.”
Hoegh-Guldberg expressed concern that the analysis shows bleaching could occur before March, which historically has been the main month for such events. “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.”