Global Heatwave Puts 73% of Coral Reefs at Risk of Bleaching

Studies have shown that a global heatwave coral reefs at risk of bleaching

Studies have shown that in a global heatwave, coral reefs are at risk of bleaching. Credit: Ryan Goehrung / Wikimedia Commons / CC BY-SA 4.0

Researchers have observed that the planet’s reefs are currently facing severe heat stress after 18 months of record-high ocean temperatures.

Data from the US government’s Coral Reef Watch reveals that 73% of the world’s corals are now bleaching. This issue affects reefs in the Pacific, Atlantic, and Indian oceans, as reported by The Guardian.

The global mass bleaching event began in February 2023. It is the fourth such event and the second in the past decade, marking it as the most widespread on record.

Growing corals in nurseries

Coral scientists believe it’s time to rethink how to protect reefs as temperatures continue to rise. Prof Tracy Ainsworth, vice president of the International Coral Reef Society, noted that after years of making predictions, scientists are now confronting a reality they hoped to avoid.

Moreover, she emphasized the need for new strategies to help reefs survive as the situation worsens.

On Monday, the scientific journal Nature Climate Change published three articles urging the coral conservation and science community to reconsider their approach.

Prof Tiffany Morrison, a co-author of one article, described this need for reflection as “soul searching.” She criticized widespread programs that focus on growing corals in nurseries and then planting them on reefs, many of which have corporate support.

Moreover, Tiffany Morrison explained that when people first understood the massive impact of climate change on coral reefs, their immediate reaction was to take action and intervene due to their distress over the situation.

Coral reefs as a source of food and raw material

Coral reefs are crucial as they provide food for millions of people globally, contribute to the sand on beaches, and protect coastlines from wave damage. When corals are exposed to excessively hot water, they expel the algae in their tissues, which give them color and nutrients.

Dr. Derek Manzello, director of Coral Reef Watch, mentioned that the number of reefs affected by heat stress is still increasing. This situation has prompted many in the field of reef science and restoration to seriously reconsider their future actions and best practices.

The current global event has affected coral reefs in 70 countries, with impacts that might never be fully known. Moreover, The Great Barrier Reef, the largest coral reef system, has likely faced its worst bleaching event.

However, government scientists will not know the full extent of coral deaths until next year, as reported by The Guardian.

In another study, Prof. Michael Webster from New York University introduced a bold idea. He mentioned that such an idea would have been too controversial to include in a scientific paper just 10 years ago.

Coral reefs are found in tropical waters worldwide and are adapted to their local environments. Prof. Michael Webster therefore suggested that conservationists should think about moving corals from very hot regions to reefs where the local corals are struggling.