Provides near-real-time information on thermal stress that induces coral bleaching for 24 selected reef sites around the globe. The information is extracted from near-real-time satellite remotely sensed global sea surface temperature (SST) measurements and derived indices of coral bleaching related thermal stress. Each reef site includes links to SST, SST Anomalies, Coral Bleaching HotSpots, Degree Heating Weeks, Time Series, SST Contour Charts, Ocean Surface Winds, and On-site Buoys as available for that reef.
Bleaching Alert Area product identifies, for the twice-weekly time period ending on the day indicated in the product, locations where thermal stress reaches various levels that can lead to coral bleaching. A scale of five coral bleaching thermal stress levels, including No Stress, Bleaching Watch, Bleaching Warning, and Bleaching Alert Levels 1 and 2, is used. The thermal stress classification is described in detail at the Coral Reef Watch BAA page. Both the Bleaching Alert Area, as well as the level of stress defined by the product, are derived from Coral Bleaching HotSpots and Degree Heating Weeks (DHW) values measured at each site for any given twice-weekly time period.
Degree Heating Weeks (DHWs) indicate the accumulation of thermal stress that coral reefs have experienced over the past 12 weeks. One DHW is equivalent to one week of sea surface temperatures one degree Celsius greater than the expected summertime maximum. Two DHWs are equivalent to two weeks at one degree above the expected summertime maximum OR one week of two degrees above the expected summertime maximum. Also called Coral Reef Degree Heating Weeks.
Coral Bleaching HotSpots are areas that have exceeded the maximum monthly mean SST by at least one degree Celsius.
This global 5km Sea Surface Temperature (SST) Anomaly product, displays the difference between today's SST and the long-term average. The scale goes from -5 to +5 °C. Positive numbers mean the temperature is warmer than average; negative means cooler than average.