Ocean temperatures in the Great Barrier Reef reached the highest they’ve been in 400 years over the past decade, research published Wednesday in the journal Nature found. Researchers from Melbourne University in Australia were able to compare recent ocean temperatures to historical ones by using coral skeleton samples from the Coral Sea to reconstruct sea surface temperature data from 1618 to 1995. They found mostly stable temperatures before 1900, and steady warming from 1960 to 2024. Temperatures were significantly higher over the past decade, when mass bleaching took place. The scientists warned that the reef likely won’t survive if planetary warming isn’t stopped.