SYDNEY, Oct. 22 (Xinhua) -- Australian researchers have identified wind patterns as a key cause of devastating coral bleaching on the Great Barrier Reef.

In a new study, researchers from Monash University in Melbourne found that wind patterns are a key cause of the spike in ocean temperatures resulting in recent mass bleaching on the reef, the university said in a media release on Monday.

Coral bleaching occurs when sea temperatures rise too high and coral under heat stress expel the symbiotic algae living in their tissue, turning the coral completely white. Corals that have been bleached are not always dead but are more likely to starve and can take up to 10 years to recover.

There have been five mass bleaching events on the Great Barrier Reef, which is the world's largest coral reef, since 2016, prompting concerns about its long-term health.

The team analyzed more than three decades of atmospheric weather and discovered the role of easterly trade winds in regulating ocean temperatures on the reef.

Lara Richards, lead researcher on the project, said that the collapse of the trade winds in 2022 drastically altered the ocean surface temperature before a bleaching event that affected 91 percent of the reef.

"During a three-week period, we observed the ocean warming in this area by almost 2 Celsius degrees to 30.5 Celsius degrees, as the absence of the trade winds allowed a decrease in cloud cover, increase in solar radiation, and lack of evaporative cooling," Richards said.

"Following the re-establishment of the trade winds, the warming ended abruptly and the ocean temperature cooled by 1 Celsius degree over 48 hours as evaporative cooling effectively tripled," she said.

Spikes in ocean temperatures causing bleaching were previously often linked to the El Nino phase of the El Nino-Southern Oscillation (ENSO), a global climate phenomenon driven by variations in winds and sea surface temperatures over the tropical Pacific Ocean.

The bleaching event in 2022 was the first to occur on the reef during a La Nina phase of ENSO, which is typically associated with lower temperatures and higher rainfall across much of Australia. Enditem

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