The 2,300km (1,429 mile) coral reef is undergoing its fifth major bleaching event since 2016, with aerial surveys showing the extent of the damage.
Australia's Great Barrier Reef, which stretches some 2,300 kilometers (1,429 miles) off Australia's northeast coast, is undergoing the worst bleaching event in history.
The aerial survey revealed the extent of the bleaching after the government agency responsible for coral reef management confirmed early last month that the reef had suffered its fifth major bleaching event since 2016.
Bleaching is a phenomenon in which corals expel the colorful microscopic algae that live in their tissues in order to survive, and was caused by rising water temperatures that began last December.
“This prolonged heat exposure caused massive bleaching of coral reef communities observed in all three regions of the Great Barrier Reef,” the Great Barrier Reef Marine Park Authority said in an update to its website on Wednesday. . “A combination of aerial and underwater surveys in 2024 confirmed a large-scale bleaching event, with widespread and extreme bleaching observed on all three reefs.”
Region of the Great Barrier Reef Marine Park. ”
The agency said it surveyed a total of 1,080 coral reefs and found that 79 percent of them had some degree of coral bleaching. According to the report, approximately 49% of the coral reefs surveyed showed high to extreme levels of bleaching, with the central and southern parts of the World Heritage-listed reef being the most affected areas. There is.
The thermal stress in the southern region was the highest recorded by the National Oceanic and Atmospheric Administration satellite since it began operations in 1985, the agency said. Bleaching rates across the area ranged from high (31 to 60 percent of cover bleached) to extreme (more than 90 percent of cover bleached). Only 3% of the coral reefs surveyed were not bleached.
Coral reefs are living things, and the Great Barrier Reef is considered one of the most species-rich habitats on Earth. It is home to hundreds of species of coral, 1,500 species of fish, and 4,000 species of mollusk.
Coral reefs protect coastal communities and are also natural carbon sinks. As they are sensitive to heat, climate change is the biggest threat to their survival.
“Only the strongest and fastest possible action to reduce global greenhouse gas emissions can reduce the risk of heat stress to coral reefs and limit the impacts of climate change on the Great Barrier Reef. ” marine park authorities said.
Corals can recover from the bleaching event, and the agency said the full impact of the bleaching event will not be known for some time. It added that underwater investigations will continue.