The United States National Oceanic and Atmospheric Administration (NOAA) has confirmed the fourth global coral bleach event in the Caribbean. Photo: Loop News

NOAA has revealed a three-panel image that shows a boulder star coral in the United States Virgin Islands, showing a shift from healthy in May last year to bleached in October 2023 to recovered in March this year, following extreme marine heat stress throughout the Caribbean basin in 2023.

“The world is currently experiencing a global coral bleaching event. This is the fourth global event on record and the second in the last 10 years,” NOAA said, adding that bleaching-level heat stress, as remotely monitored and predicted by its Coral Reef Watch (CRW), has been and continues to be extensive across the Atlantic, Pacific and Indian Ocean basins.

NOAA said CRW’s heat-stress monitoring is based on sea surface temperature data, spanning 1985 to the present, from a blend of NOAA and partner satellites.

“From February 2023 to April 2024, significant coral bleaching has been documented in both the Northern and Southern Hemispheres of each major ocean basin,” said Dr Derek Manzello, NOAA CRW coordinator.

Manzello said that, since early 2023, mass bleaching of coral reefs has been confirmed throughout the tropics, including the Caribbean.

“As the world’s oceans continue to warm, coral bleaching is becoming more frequent and severe. When these events are sufficiently severe or prolonged, they can cause coral mortality, which hurts the people who depend on the coral reefs for their livelihoods.”

Manzello said coral bleaching, especially on a widespread scale, impacts economies, livelihoods, food security and more, “but it does not necessarily mean corals will die.

“If the stress driving the bleaching diminishes, corals can recover and reefs can continue to provide the ecosystem services we all rely on,” he said.

The director of NOAA’s Coral Reef Conservation Programme (CRCP), Jennifer Koss, said, “climate model predictions for coral reefs have been suggesting for years that bleaching impacts would increase in frequency and magnitude as the ocean warms”.

She said in light of this, the NOAA CRCP incorporated “resilience-based management practices and increased the emphasis on coral restoration in its 2018 strategic plan, and funded a National Academies of Sciences’ study, which led to the publication of the 2019 Interventions to Increase the Resilience of Coral Reefs.

“We are on the frontlines of coral reef research, management and restoration, and are actively and aggressively implementing the recommendations of the 2019 Interventions Report,” Koss said.

She said the International Coral Reef Initiative (ICRI), which NOAA co-chairs, and its international members are “broadly sharing and already applying resilience-based management actions and lessons learned from the 2023 marine heatwaves in Florida and the Caribbean.”