Great Barrier Reef forecast warns entire system at risk of bleaching and coral death this summer

US oceanographic agency forecasts 60% chance of extreme heat stress and bleaching

Mass bleaching and coral death could be likely along the entire Great Barrier Reef this summer, according to a long-range forecast that coral experts say is "a wake-up call" for the Australian government.

The US National Oceanographic and Atmospheric Administration (Noaa) has forecast a 60% chance that the entire Great Barrier Reef will reach alert level one, which signals extreme heat stress and bleaching are likely.