By a new study, off the coast of Australia, the Great Barrier Reef has seen two huge bleaching events over the span of two years, and that has led to a widespread die-off of the corals.
Through keen observations of the largest coral reef system of the world, the scientists are taking stock of the extent of the damage from the higher water temperatures due to global warming. They mapped the patterns of exposure to heat on more than 1,400 miles of reef and analyzed which corals are dying, learning the future of these reefs.
Mark Eakin of the NOAA’s Coral Reef said that it has been an event that is changing the character of these reefs, and now that these marine heat waves are coming more frequently and more severely, they expect this kind of damage to keep occurring on coral reefs around the world. He further said that the bleaching had altered the entire community of the corals living on many of these reefs, killing many of the more temperature-sensitive corals and leaving just a community that is kind of homogenized or flattened. Eakin added that either of the catastrophic back-to-back bleachings would have been the worst that they have ever seen.
By research published, the die-off has brought about the collapse of the ecosystem for 29 percent of the 3,863 reefs in the giant coral reef system. The detailed mapping builds on earlier research, which primarily relied on aerial surveys, and was conducted by a team of U.S. and Australian scientists.
As said by Eakin, the scientists are stressed as they found that the corals were dying at a lower level of heat stress than they expected to see. It is possible that could be as the reefs in the extreme north of the Great Barrier Reef have not been exposed to significant heat stress in the past.