Australia’s Great Barrier Reef is deteriorating – 03/08/2024 – Environment

Australia’s Great Barrier Reef is undergoing a massive bleaching process, a deterioration caused by climate change that involves the reefs losing color, the country’s authorities said this Friday (8).

Described as the largest living structure on Earth, the Great Barrier Reef is a 2,300 km long reef that is home to a wide range of biodiversity.

But repeated bleaching processes, caused by high temperatures, threaten to destroy the structure, which is considered a World Heritage Site by UNESCO.

“We know that the biggest threat to the world’s coral reefs is climate change. The Great Barrier Reef is no exception,” Australian Environment Minister Tanya Plibersek said in a statement.

“We need to act against climate change. We need to protect our special places and the plants and animals that live in them,” he added.

The damage was confirmed by Australian government scientists after analyzing 300 near-surface reefs from aircraft. The Great Barrier Authority said it does not need to carry out further studies to assess the severity and extent of the deterioration.

The destruction scenario had already been highlighted on Tuesday (5) by Noaa (American atmospheric and oceanic agency). Scientists from the entity warned that the world is about to have the fourth mass coral bleaching event.

“The entire Southern Hemisphere will likely experience bleaching this year,” said ecologist Derek Manzello, coordinator of NOAA’s Coral Reef Watch, which serves as the global authority for monitoring coral bleaching risk. “We are literally on the brink of the worst bleaching event in the history of the planet.”

Earth has experienced months of record ocean heat, driven by climate change and the El Niño phenomenon.

Ocean surface temperatures in February around the world were the highest ever recorded in history. The average for the month reached 21.06°C, breaking the previous record, from August 2023, when the index was 20.98°C, show data from the European climate observatory Copernicus released this Thursday (7).

Bleaching occurs when marine temperatures are 1°C above the long-term average.

Faced with this thermal stress, corals expel the algae that live in their tissues, which leads to the loss of their vibrant colors.

Ocean temperatures in the Great Barrier Area have been approaching their all-time highs in recent weeks, according to official data.

Richard Leck, director of oceans in Australia at the NGO WWF, warned that large quantities of corals are likely to die if sea temperatures do not cool quickly in the coming weeks.

“The bleaching process is happening in an area where corals have not previously been exposed to extreme temperatures,” he explained.

Climate change puts enormous pressure on the Great Barrier. Some coral species have proven to be more resilient and may recover as water temperatures drop.

Terry Hughes, one of Australia’s leading coral experts, however, warned that bleaching processes occur so frequently that reefs have barely been able to begin recovery.

“The reef is no longer able to return to the mix of coral species and coral sizes it had 20 years ago,” he said.

“The irony is that the corals that currently prevail in most of the Great Barrier are fast-growing corals that resurface quickly, but the problem is that they are sensitive to heat and less tolerant of the next inevitable process of bleaching,” he explained.