The Great Barrier Reef has been “extended” to whitening again, authorities said on Friday, as ocean temperatures in north-eastern Australia threaten a higher-than-average World Heritage site.
Reef surveillance flights over the 2,300-kilometer (1,243-mile) coral network revealed damage from low and severe heat stress through mild to severe bleaching, the Great Barrier Reef Marine Park Authority said.
“Whitening has been detected in the Marine Park; it is widespread but variable, in several regions, with a serious impact from small,” authorities said in a weekly update.
Over the past week, sea temperatures throughout the marine park have averaged between 0.5 and two degrees Celsius, with temperatures averaging between two and four degrees in the far north and onshore areas.
“The largest year-old reefs are in the Townsville area. There have also been reports of early mortality where heat stress has been greatest.”
The news comes ahead of a trip to UNESCO to inspect the health of the reef site, announcing a decision on the heritage list to be examined in June.
Whitening occurs when healthy corals are stressed by the peaks of ocean temperatures, and they expel algae that live in their tissues, draining bright colors.
There have been five whitening events on the Great Reef since 1997 due to unusual warm sea temperatures, which have left many of the damaged corals struggling to survive.
Several cyclones have also hit the reef, as climate change is pushing for extreme weather.
The appearance of star-crowned crowns has also eaten away at the coral.
Although recent changes are not yet classified as a massive bleaching event, the Australian Marine Conservation Association has described the report as “disastrous news”, especially in the La Nina weather pattern, which is often linked to cooler ocean temperatures.
“Our reef shows the consistent pressure it is currently experiencing as a result of global warming,” said Lissa Schindler, the association’s campaign manager.
“A healthy reef can be recovered from coral bleaching, but it takes time. More frequent heat waves at sea, especially due to the burning of coal and gas, means that the current is not being achieved.”
The Australian Conservative government announced new funding earlier this year to prevent the climate-damaged reef from being removed from the UNESCO World Heritage List.
When the UN threatened to lower the reef’s World Heritage List in 2015, Australia created a “Reef 2050” plan and spilled billions of dollars in support.
Measures are believed to have slowed the pace of decline, but many of the world’s largest reef systems have already been damaged.
A recent study found that bleaching had affected 98 percent of the reef since 1998, leaving only part of it untouched.
The Great Barrier – the world’s largest living structure, visible from space – was added to the list in 1981 for its “magnificent natural beauty” and wide biodiversity.
But the list is not finalized, and the sites may be reduced or even removed altogether, with the recommendation of the UN body.
While not putting them on the “endangered” list is punishable – some nations have added their own sites to gain international attention to help save them – others see it as a disgrace.
(This story was not edited by NDTV staff and was automatically created from a union feed.)