AUSTRALIA’S Great Barrier Reef is suffering a “mass bleaching event” as corals come under heat stress from warmer seas, said reef authorities today.

An aerial survey showed coral bleaching at multiple reefs, “confirming a mass bleaching event, the fourth since 2016”, said a report by the Reef Authority, which manages the largest coral reef system in the world.

Corals suffer despite the cooling effect of the La Nina weather phenomenon that is currently influencing the climate in the country, it added.

Scientists said climate change leading to warmer waters is one of the main drivers of coral bleaching.

It occurs when corals expel algae living in their tissues, draining them of their vibrant colours.

Though bleached corals are under stress, they can still recover if conditions become more moderate, said the authority.

“Weather patterns over the next couple of weeks continue to remain critical in determining the overall extent and severity of coral bleaching across the Marine Park.”

The mass bleaching report comes four days after the United Nations (UN) started a monitoring mission to assess whether the World Heritage site is being protected from climate change.

Unesco’s mission is to assess whether the government is doing enough to address threats to the Great Barrier Reef – including climate change – before the World Heritage Committee considers listing it as “in danger” in June.

The committee’s decision to not list it as such last July surprised many, given that Unesco recommended the listing just weeks earlier.

When the UN threatened to downgrade the reef’s World Heritage listing in 2015, Australia created a Reef 2050 plan and poured billions of dollars into its protection. – AFP, March 25, 2022.