Parts of the Great Barrier Reef are showing signs of heat stress, raising the risk of another major coral bleaching event, scientists from the Great Barrier Reef Marine Park Authority have announced. Eastern Australia has experienced a long period of warmer than usual ocean currents, which has increased water temperatures across two-thirds of the reef 2 to 3 degrees Celsius above average for February, Reuters reported.
Scientists warned that if water temperatures do not drop in the next two weeks, the bleaching would likely become widespread. It would be Australia’s third major coral bleaching event in five years, with the others in 2016 and 2017.
“We are down to the wire,” Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, told The Guardian.
Marine biologists are closely monitoring the reef, conducting diving surveys and helicopter patrols, as well as working with citizen science volunteers to collect data. One scientist told Reuters that he had seen some level of bleaching of 30 to 40 percent of the coral in shallow waters.
The news comes on the heels of a new report that says warming ocean temperatures, acidification, and pollution could kill about 70 to 90 percent of all existing coral reefs in the next 20 years. Nearly all the world’s coral could be gone by 2100, according to the study, which was led by researchers at the University of Hawaii Manoa.