Coral reefs are bleaching way more frequently because of global warming - the rate of bleaching has increased more than fourfold in the past four decades — from once every 25 to 30 years back in the 1980s, to once every six years by 2016.

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Coral reefs are bleaching way more frequently because of global warming - the rate of bleaching has increased more than fourfold in the past four decades — from once every 25 to 30 years back in the 1980s, to once every six years by 2016.