For an unprecedented second year in a row, Great Barrier Reef coral have been decimated by a wave of warm water. Last year’s mass bleaching was fueled in part by a powerful El Niño. Research showed that climate change made warm waters in the Coral Sea up to 175 times more likely. While no similar attribution has been done for this year’s mass bleaching, 2017’s heat is occurring in the absence of El Niño. And there’s one main culprit scientists are pointing to.
— source climatecentral.org