The world's largest coral reef will suffer its seventh "mass bleaching" since 1998. This phenomenon of dieback is caused by an increase of one degree in the water temperature.
The reef is home to some 1,500 species of fish and 4,000 types of molluscs. The future of the reef has been a source of tension between the Australian government and UNESCO, which threatened to put it on a list of “in danger” world heritage sites. The Great Barrier Reef generates $4.8 billion in revenue.