Hottest oceans in 400 years endanger Great Barrier Reef, scientists say
Australia's Great Barrier Reef faces severe threats from record-high water temperatures, with rising warmth linked to climate change over 400 years.
Two clownfish swim inside of a sea anemone in the Great Barrier Reef off the coast of Cairns, Australia October 26, 2019.(photo credit: REUTERS/LUCAS JACKSON)