The Impact of Coral Reef Bleaching Due to Climate Change
A recent report highlighting that 77% of the world’s coral reefs are affected by bleaching, mainly due to warming ocean waters caused by human-induced climate change, reveals an alarming situation for these vital marine ecosystems.
The crisis is the largest and fourth global bleaching event on record, now affecting both hemispheres, according to the UN Fund for Critical Development. In light of these alarming findings, a special UN emergency session was convened on Wednesday, usually reserved for resolving escalating conflicts or natural disasters, to address the issue of corals on the sidelines of the UN biodiversity summit, COP16, which is coming to a close after two weeks in Cali, Colombia.
“We are at a critical juncture. The evidence is undeniable,” Margaux Monfared, head of international policy and advocacy at the International Coral Reef Initiative, said at a press conference Tuesday ahead of the emergency session. “Immediate and decisive action is needed to address the threats to the world’s coral reefs to prevent their functional collapse.”
Coral reefs are vital ecosystems that support more than 25 percent of marine life and nearly a billion people, many of whom depend on reefs for food security, coastal protection and livelihoods, the UN Development Fund said.
Following Wednesday’s emergency session, the governments of New Zealand, the United Kingdom, Germany and France made new pledges totalling around $30 million to the UN Coral Reef Fund, established in 2020. By 2030, the fund aims to mobilise up to $3 billion in public and private funding to support coral reef conservation efforts, with $225 million already raised.
Next year, a UN ocean conference will be held in Nice, France, and countries are being urged to make early pledges to contribute more to the UN Global Coral Reef Fund, with the aim of mobilising an additional $150 million in donations by the conference.
A change in water temperature can cause corals to expel algae that provide nutrition, causing them to lose their colour and become stressed. Corals can also bleach for other reasons, such as extremely low tides, pollution, or excessive exposure to sunlight..
In the world’s largest coral reef ecosystem, Australia’s Great Barrier Reef, 90% of assessed corals were affected by bleaching in 2022. The Florida Reef, the third largest, experienced significant bleaching last year.
It is clear that concrete and immediate action is needed to protect these critical marine habitats and prevent their collapse. The international community must come together and step up its efforts to save coral reefs and the precious marine biodiversity they support.