Harmful bleaching of the world’s coral has grown to include 84% of the ocean’s reefs in the most intense event of its kind in recorded history, the International Coral Reef Initiative announced Wednesday.

The world's rainbow reefs have gone ghostly white in seas around the globe due to record heat in the oceans, the International Coral Reef Initiative reports. But scientists say the reefs aren't all dead yet and could still bounce back if people take the right steps.