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Coral bleaching Hotspots

Healthy coral reefs provide a home for millions of aquatic species. They protect coastal homes from storms and support commercial and subsistence fisheries as well as jobs and businesses through tourism and recreation. Yet they are severely threatened by pollution, disease, habitat destruction and climate change. When corals are stressed, they expel the symbiotic algae living in their tissues and become white (bleached) and vulnerable. Corals are vulnerable to bleaching when the sea surface temperature (SST) exceeds the temperatures normally experienced in the hottest month of the year. The NOAA Coral Reef Watch daily global 5km Coral Bleaching HotSpot product measures the occurrence and magnitude of instantaneous heat stress, potentially resulting in coral bleaching. It highlights regions where the SST is warmer than the highest monthly mean. HotSpot values of 1°C or more indicate heat stress leading to coral bleaching and are highlighted in yellow to dark red colors.