The Great Barrier Reef is in the grip of a mass coral bleaching event driven by global heating – the fifth in only eight years – the marine park’s government authority has confirmed.
The authority, together with scientists from the Australian Institute of Marine Science, have completed aerial surveys across 300 reefs over two-thirds of the reef, with more to come.
The Great Barrier Reef – the biggest coral system in the world – is about 2,300km long, covers an area bigger than the size of Italy and is made up of about 3,000 individual reefs.
Widespread mass bleaching of the Great Barrier Reef was first seen in 1998 and happened again in 2002, 2016, 2017, 2020, 2022 and now in 2024.
Ocean temperatures around the world have been the highest on record for almost a year and the US government’s Coral Reef Watch program has said the planet is on the cusp of a fourth global mass coral bleaching event, with reefs in the Atlantic, Pacific and potentially the Indian Ocean all bleaching.
According to Coral Reef Watch data, the heat stress on corals in the reef’s southern and central region has been the highest on record, and the second highest in northern areas.
Coral Watch has observed 4-metre-wide boulder corals that take hundreds of years to grow bleached bone white.