Ocean temperatures over parts of the Great Barrier Reef have reached record levels this month, sparking fears of a second summer in a row of mass coral bleaching.
Data from the US government’s National Oceanic and Atmospheric Administration (Noaa) shows sea surface temperatures over the northern parts of the reef have been the highest for any November on a record going back to 1985.
With the peak period for accumulated heat over the reef not expected until February, cooler weather conditions and cyclone activity before then could stave off a mass bleaching event.
Prof Terry Hughes, a leading expert on coral bleaching at James Cook University, said he had never seen heat stress accumulating on the reef this early, but a “well timed cyclone” in December could reduce the risk of bleaching.
Rising ocean temperatures driven by human emissions of greenhouse gases mostly from burning fossil fuels caused six mass bleaching events along the reef in 1998, 2002, 2016, 2017, 2020 and 2022.
The bleaching of last summer that affected 91% of all individual reefs came after record ocean temperatures over the reef in December.
More information:
https://www.theguardian.com/environment/2022/nov/25/record-heat-over-great-barrier-reef-raises-fears-of-second-summer-of-coral-bleaching