Coral bleaching explained

WHAT IS CORAL BLEACHING?

- Bleaching occurs when live corals become stressed from overheating

- Scientists say climate change is driving bleaching events by pushing up sea temperatures

- When conditions are too warm, stressed corals expel tiny photosynthetic algae, called zooxanthellae

- The loss of these colourful algae causes the corals to turn white

- Bleached corals can recover if waters cool down

- If corals remain stressed for many weeks, they die

- Reef experts say it takes about 10 years for affected reefs to recover from major bleaching events

- Experts fear for the overall health of the reef if major bleaching events regularly begin to occur within a decade of each other

- Scientists involved in aerial surveys say the 2016 bleaching event that's affecting the Great Barrier Reef is far worse than the previous two in 2002 and 1998

Source: ARC Centre of Excellence for Coral Reef Studies/Great Barrier Reef Marine Park Authority