The Intergovernmental Panel on Climate Change (IPCC) recently released a report highlighting the grave impacts of climate change on the Great Barrier Reef. The world’s largest coral reef complex, situated in the Pacific Ocean off north-eastern Australia, is undergoing significant damage due to global warming. The report points towards three previous mass bleaching events that devastated a considerable proportion of coral between 2016 and 2020. It further warns of “mass mortality” within some coral species.
Findings of the Report
The IPCC report mainly emphasizes that warming ocean temperatures are leading to frequent and severe coral bleaching. The worst bleaching event occurred in 2016, affecting over 90% of the reef. A series of successive bleaching incidents has led to the northern and middle parts of the reef system being in a particularly degraded state.
Even if we manage to limit future warming to 1.5 degrees Celsius above pre-industrial levels, it may not be enough to prevent more frequent mass bleaching events, although it might reduce their occurrence. Rising ocean temperatures and marine heatwaves could cause widespread destruction of tropical shallow coral reefs, leading to the loss and degradation of coral reef ecosystems.
If bleaching continues, the IPCC estimates unsustainable economic losses from declining tourism. Around a billion people worldwide depend on coral reefs for their livelihoods, making urgent greenhouse gas emissions reductions critical to prevent devastating effects on humanity.
Anti-Climatic Changes in Australia
Climate change impacts extend beyond the reef. Australia could expect a surge in heat-related deaths, animal extinctions, and increased wildfires. Koalas face local extinctions due to rising drought and temperatures. Moreover, rising sea levels and storm surges have already driven the extinction of the Bramble Cay melomys, a rodent species once inhabited a remote cay in the northern Great Barrier Reef.
Australia’s famed eucalyptus trees may not withstand predicted fire severity and frequency, leading to potential forest decimation. The Black Summer fires of late 2019 and early 2020 were devastating, killing at least 33 people and destroying more than 3,000 homes.
The Great Barrier Reef: A Global Wonder
The Great Barrier Reef is the world’s most extensive coral reef ecosystem, composed of over 2,900 individual reefs and 900 islands off the Queensland coast in Australia. It is an extraordinary structure, built by billions of tiny organisms known as coral polyps and visible from outer space.
These polyps form mutualistic relationships with microscopic algae, or zooxanthellae, living within their tissues, creating a hard limestone skeleton at their base. In 1981, it was recognized as a World Heritage Site for its incomparable biodiversity and inspiring natural beauty.
Global Initiatives to Protect Coral Reefs
Several global initiatives are addressing these issues, such as the International Coral Reef Initiative, Global Coral Reef Monitoring Network, and the Global Coral Reef R&D Accelerator Platform. Domestic initiatives are also critical. In India, the Ministry of Environment, Forests, and Climate Change has launched studies on coral reefs under the Coastal Zone Studies. Efforts include the use of “biorock” or mineral accretion technology to restore coral reefs and a National Coastal Mission Programme dedicated to protecting and sustaining the country’s coral reefs.
