New study on the severe 2020 coral bleaching event in the tropical Atlantic linked to marine heatwaves

The study reveals that MHWs have increased in frequency, intensity, duration, and spatial extent since records began in 1982. Notably, the summer/fall of 2020 saw the largest coral bleaching event along the Brazilian coast, with 85% of stony corals and 70% of zoanthids affected in Rio do Fogo. This event was driven by an unprecedented marine heatwave in the western tropical Atlantic.

The study highlights that the severity of MHWs in the region is rising, despite no significant changes in local drivers. This suggests that even weaker local forces can lead to devastating impacts as global ocean temperatures increase due to climate change. The research underscores the importance of understanding the physical drivers of MHWs to improve predictability and guide future climate adaptation and mitigation strategies.