Unprecedented Coral Bleaching Engulfs the Great Barrier Reef Amid Rising Ocean Temperatures

The Great Barrier Reef has faced its most extensive coral bleaching yet, as ocean temperatures reached unprecedented levels in 2024, according to a report by Al Jazeera citing Australian government findings. The Australian Institute of Marine Science (AIMS) conducted surveys between August 2024 and May 2025, revealing widespread bleaching unprecedented since records began in 1986, driven mainly by climate change-induced heat stress.

In the southernmost region of the reef, coral cover declined by nearly a third to only 26.9 percent, where heat stress was at historic levels. According to scientists, the decrease in coral cover marks the most significant single-year decline in both the north and south since monitoring commenced 39 years ago. Spanning 2,300 kilometers and rich in diversity, the Great Barrier Reef is known as the world's largest living structure.

AIMS CEO Professor Selina Stead emphasized the increasing intensity and frequency of mass bleaching events, calling for significant reductions in greenhouse gas emissions to safeguard coral reefs globally. She highlighted the importance of managing local stressors and aiding the reefs' adaptation and recovery from climate change impacts. The Great Barrier Reef is a UNESCO World Heritage Site, housing the largest collection of coral reefs and diverse marine life, including species like the dugong and the large green turtle.

The debate over the reef's endangered status by United Nations experts is met with resistance from the Australian government due to potential tourism revenue impacts. The Climate Change Authority's recent report suggests that adopting low or zero-emission alternatives by major fossil fuel exporters could protect the reef, highlighting the urgent need to address climate pollutants like methane, which significantly contribute to near-term warming. Despite these challenges, Australia remains a major fossil fuel exporter. The authority emphasized that a staggering 93 percent of the atmospheric excess heat has been absorbed by oceans, with 2024 temperatures surpassing 2023's record.