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Coral Bleaching

Bleaching Alert Area

This resource provides current data on coral bleaching thermal stress at 24 reef sites worldwide, extracted from satellite remote sensing of global sea surface temperatures. Each site offers links to various data sets, such as sea surface temperature anomalies, coral bleaching hotspots, and on-site buoy data.

POES & GOES | Resolution: 5km | Frequency: Daily

CRW Satellite Bleaching Alerts

The Bleaching Alert Area product tracks thermal stress levels twice a week, indicating potential coral bleaching risk across different categories, from No Stress to Bleaching Alert Levels 1 and 2. It relies on Coral Bleaching HotSpots and Degree Heating Weeks values for classification, with detailed information accessible on the Coral Reef Watch BAA page.

POES & GOES | Resolution: 5Km | Frequency: Daily

Degree Heating Week Charts

Degree Heating Weeks (DHWs) gauge the thermal stress endured by coral reefs over 12 weeks, reflecting temperatures exceeding the expected summertime maximum by one degree Celsius per week. This accumulation can comprise two weeks at one degree above the expected maximum or one week at two degrees higher. DHWs are also known as Coral Reef Degree Heating Weeks.

POES & GOES | Resolution: 5Km | Frequency: Daily


Coral Bleaching HotSpots are areas that have exceeded the maximum monthly mean SST by at least one degree Celsius.

POES & GOES | Resolution: 5km | Frequency: Daily

SST Anomaly Charts

The global 5km Sea Surface Temperature (SST) Anomaly product illustrates the difference between today's sea surface temperature (SST) and the long-term average. The scale ranges from -5 to +5 degrees Celsius. Positive values indicate that the temperature is warmer than the average, while negative values indicate it is cooler than the average.

POES & GOES | Resolution: 5km | Frequency: Daily