Uploaded October 2024 | Updated September 2026, 8 hours ago
On April 15, the U.S. National Oceanic and Atmospheric Administration (NOAA) and the International Coral Reef Initiative announced that the world is now facing its fourth Global Coral Bleaching Event on record. This massive bleaching event, which began in early 2023, is affecting coral reefs in over 70 countries and territories across all major oceans. So far, more than 74% of global coral reefs have experienced extreme heat stress—surpassing previous bleaching records from 2014 to 2017, when 65% of reefs were affected.
In response, authorities in popular tourist spots like Pling Island in Phuket, Thailand, have closed access to coral sites, and the Maldives has temporarily halted all coastal development projects to minimize additional damage to stressed corals. The Atlantic Ocean has seen some of the highest levels of heat stress ever recorded, with temperatures 2–3 times higher than anything in NOAA’s historical satellite data.
In the Caribbean and South Atlantic, heat stress has reached critical levels, causing coral losses of up to 99% in some areas. Over the past year, 99.9% of Atlantic reef areas have suffered bleaching-level heat stress, leading to significant coral die-offs. Coral reef regions across the Pacific, southern Great Barrier Reef, and the Indian Ocean (like the Seychelles) have also experienced unprecedented heat levels.
The full impact of this marine heatwave will unfold in the coming months and years, but early reports are concerning. Many shallow-water corals in Florida, Mexico, and Puerto Rico are facing near-total mortality rates of 90–100%—a loss that could fundamentally alter these ecosystems.
In this presentation, Dr. Derek Manzello provides the latest updates on this record-breaking marine heatwave and its impact on coral reefs worldwide.
More NEDTalks:
nesdis.noaa.gov/data-research-services/data-collections/nedtalks
On April 15, the U.S. National Oceanic and Atmospheric Administration (NOAA) and the International Coral Reef Initiative announced that the world is now facing its fourth Global Coral Bleaching Event on record. This massive bleaching event, which began in early 2023, is affecting coral reefs in over 70 countries and territories across all major oceans. So far, more than 74% of global coral reefs have experienced extreme heat stress—surpassing previous bleaching records from 2014 to 2017, when 65% of reefs were affected.
In response, authorities in popular tourist spots like Pling Island in Phuket, Thailand, have closed access to coral sites, and the Maldives has temporarily halted all coastal development projects to minimize additional damage to stressed corals. The Atlantic Ocean has seen some of the highest levels of heat stress ever recorded, with temperatures 2–3 times higher than anything in NOAA’s historical satellite data.
In the Caribbean and South Atlantic, heat stress has reached critical levels, causing coral losses of up to 99% in some areas. Over the past year, 99.9% of Atlantic reef areas have suffered bleaching-level heat stress, leading to significant coral die-offs. Coral reef regions across the Pacific, southern Great Barrier Reef, and the Indian Ocean (like the Seychelles) have also experienced unprecedented heat levels.
The full impact of this marine heatwave will unfold in the coming months and years, but early reports are concerning. Many shallow-water corals in Florida, Mexico, and Puerto Rico are facing near-total mortality rates of 90–100%—a loss that could fundamentally alter these ecosystems.
In this presentation, Dr. Derek Manzello provides the latest updates on this record-breaking marine heatwave and its impact on coral reefs worldwide.
More NEDTalks:
nesdis.noaa.gov/data-research-services/data-collections/nedtalks
