An anonymous reader quotes a report from the BBC: Increasingly frequent marine heatwaves can lead to the almost instant death of corals, scientists working on the Great Barrier Reef have found. These episodes of unusually high water temperatures are — like heatwaves on land — associated with climate change. Scientists studying coral after a heat event discovered that extreme temperature rises decayed reefs much more rapidly than previously thought. The study revealed that corals became up to 15% weaker after an extreme heat event, causing some fragments to actually break off from the reef. The study has been published in the journal Current Biology.