Catastrophic coral bleaching in Australia's Great Barrier Reef reaches unprecedented levels, according to a recent study.
The Great Barrier Reef, a world heritage site and home to over 1,500 species of fish and 411 species of hard corals, is facing a crisis. A series of severe mass bleaching events since 1998 have taken a toll on the reef, with the most recent event in 2024 causing the largest decline in its history.
The bleaching was caused by surging water temperatures, combined with the El Niño weather pattern, which led to the corals expelling algae and losing their vibrant colours. This event had the largest spatial footprint ever recorded on the Great Barrier Reef, with between a quarter to a third of its hard coral cover lost across three main regions.
The decline in the Great Barrier Reef is a call to action. The non-profit Queensland Conservation Council is urging state and national leaders to reduce emissions and shut down coal power stations to prevent further degradation.
Current efforts to protect the reef focus on urgent climate action, reef management, and policy changes. Key strategies include strong commitments to drastically cut greenhouse gas emissions, especially by aiming for a 90% reduction by 2035. This is coupled with ending new coal and gas projects and addressing local stressors like water pollution and deforestation in reef catchments.
Effective reef management also involves scaling up monitoring and scientific research networks, tackling local threats, and implementing international and national policies that focus on reef resilience. For instance, the Great Barrier Reef Marine Monitoring Network (GCRMN) and the Australian Institute of Marine Science (AIMS) Long-Term Monitoring Program (LTMP) track coral health and bleaching events to inform decision-making.
The Australian Marine Conservation Society is urging the Federal Government to take these steps urgently to prevent further degradation of the Great Barrier Reef, which has suffered five mass bleaching events since 2016. These climate-driven bleaching events have caused a sharp decline in coral cover, exacerbated by additional stressors such as cyclones and crown-of-thorns starfish outbreaks.
UNESCO has also pressured Australia to improve reef protection policies by February 2026, under threat of listing the Great Barrier Reef as World Heritage 'In Danger.' This underscores the global urgency of these efforts.
The Great Barrier Reef is not just a natural wonder; it contributes billions of dollars to the Australian economy annually, primarily through tourism. Reefs also provide vital protection for coastlines, reducing the impact of floods, cyclones, and sea level rise.
However, the report warns that the future coral reefs are unlikely to resemble those of the past, and there is a need for more research into reef adaptation and protection while the world works to reduce greenhouse gas emissions. The declines in the north and south were the largest in a single year since monitoring began 39 years ago, and the reef may reach a point from which it cannot recover.
Oceans now store 90% of the excess heat from global warming, and each of the last eight years has set a new record for the amount of heat stored in the ocean. This underscores the need for urgent action to protect the Great Barrier Reef and other coral reefs around the world.
- The unprecedented decline in the Great Barrier Reef's health is raising concerns not only for its future but also for the environmental science community, as it signifies the consequences of climate change.
- Acknowledging the critical role of the Great Barrier Reef in maintaining the health-and-wellness of marine ecosystems, as well as contributing significantly to the Australian economy, it is evident that climate-change mitigation efforts should be prioritized.
- The Australian government's commitment to tackling climate change isn't solely for the sake of the environment but also for the wellbeing of the people, as a healthy environment equates to mental health and overall health and wellness based on the current understanding of the science behind the interconnection between human health and environmental health.
