Future risk of coral bleaching set to itensify globally

An international team of researchers led by the 成人大片 has projected future marine heatwaves will cause coral reefs to be at severe risk of bleaching for longer periods than previously seen.

Photo of bleached corals

Bleached corals on John Brewer Reef, Great Barrier Reef. Credit: Neal Cantin, Australian Institute of Marine Science.

Through climate modelling and supercomputing, the researchers discovered that extended bleaching events may significantly disrupt coral spawning.

鈥淲e found that听coral bleaching will start earlier in the year and last longer than previously thought,鈥 said听lead author Dr , from the 成人大片鈥檚 Environment Institute.

鈥淥ur results show that听by 2080, coral bleaching will tend to start in spring, rather than late summer, which could听potentially threaten coral reproduction success.

鈥淚n many regions coral spawning occurs once a year, in spring, and our modelling projects a high risk that coral bleaching will coincide with this reproductive event, which will be devastating for thousands of coral species.鈥

Marine heatwaves cause corals to become stressed and expel the symbiotic algae living in their tissue, leaving corals white and weakened.

While widespread coral bleaching is a recent phenomenon, four global mass bleaching events have occurred since 1998, the most recent two occurring in this decade.

This recent discovery,听, establishes the severity, timing and duration of severe bleaching risk in the 21st听century for Earth鈥檚 coral reefs, showing that mass bleaching events are going to continue to become even more frequent in the future.

鈥淥ur projections of daily heat stress show that the greatest risk of severe coral bleaching this century will be along the equator, which is also home to the most biodiversity-rich coral reefs,鈥 said Associate Professor , from the 成人大片鈥檚 Environment Institute.

鈥淐oral reefs in these equatorial regions, including Indonesia鈥檚 Coral Triangle, could face near constant bleaching conditions by the end of the century.

鈥淯nfortunately, marine species in these regions听are already living at temperatures near their upper tolerance levels and so are particularly ill-equipped to adapt to accelerated climate change, making them highly vulnerable to extinction.鈥

Low-latitude coral reef regions support food and nutrition for millions of people worldwide, with local populations relying on coral reef fisheries for income.

These new results, accompanied by an听, will help reef managers identify regions of lower bleaching risk where coral conservation actions can be prioritised and corals best saved.

鈥淥ur validated projections of future coral bleaching risk are based on daily marine heatwave forecasts, which represent a critical improvement over past approaches鈥 said Professor Scott Heron, a co-author from James Cook University.

鈥淭hese next-generation projections will be crucial for developing conservation strategies aimed to protect and restore coral reefs in regions at lesser risk of future climate change. These are areas where conservation success is most likely.鈥

Originally published on the 成人大片 Newsroom.

Further information also available in an article published by .

Tagged in coral bleaching, camille mellin, damien fordham, The Conversation
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