NOAA Modeling - GBR May Face 4th Mass Bleaching Event In 6 Years, In Spite Of La Nina
A global weather phenomenon that would typically keep ocean temperatures lower across the Great Barrier Reef may not be enough to stop another mass coral bleaching this coming summer, according to the marine parks chief scientist.
Global heating now meant the risk of corals bleaching from heat stress was present even in a summer influenced by the La Niña climate phenomenon, the Great Barrier Reef Marine Park Authoritys Dr David Wachenfeld told Guardian Australia.
On Thursday the authority revealed this summers outlook for the worlds biggest coral reef system that has been hit by three mass bleaching events in the past five years. Clouds, rain and cyclones could still combine to keep temperatures along the reef low enough to avoid another bleaching event.
But modelling from the US governments National Oceanic and Atmospheric Administration (Noaa) and Australias Bureau of Meteorology were in agreement that December and January would probably see ocean temperatures over the reef about 1C warmer than average. There is not a forecast of a mass bleaching event, but its certainly possible and everything hangs on this consideration of a typical La Niña, Wachenfeld said. The whole world is one degree warmer, so we cant just relax and say its a La Niña and so there wont be heatwaves. The world is not that simple any more.
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https://www.theguardian.com/environment/2020/nov/26/cooling-la-nina-may-not-save-great-barrier-reef-from-mass-coral-bleaching-experts-warn