Coral Reef Watch Satellite Bleaching Alert System

NOAA's Coral Reef Watch (CRW) Satellite Bleaching Alert (SBA) system is an automated coral bleaching e-mail alert system designed to monitor the status of thermal stress conducive to coral bleaching via the use of the CRW global satellite near-real time HotSpot suite of products. The SBA was developed by the NOAA CRW satellite team as a tool for coral reef managers, scientists, and other interested people. The SBA became operational in July 2005. Currently, the alert messages are available for a number of coral reefs around the world (see the subscription page for a list of available reef sites). A sample of the SBA message can be viewed here.

An automated e-mail will be sent to a subscriber for a reef site when the status level of thermal stress changes regardless of the current status level, or when the current Degree Heating Week value exceeds the historical maximum Degree Heating Week value for that reef site. The status level of thermal stress at selected reef sites is updated twice per week.

There are five status levels: "No Stress", "Bleaching Watch","Bleaching Warning","Bleaching Alert Level 1" and "Bleaching Alert Level 2". These levels are defined in terms of the CRW HotSpot and Degree Heating Weeks (DHW) products:

alert levels

The existence of a HotSpot value indicates that thermal stress potentially conducive to bleaching is present, and the value of the HotSpot quantifies the intensity of the thermal stress. A Degree Heating Week (DHW) is a measure of accumulated thermal stress over a consecutive 12-week period.

Please note that since the DHW is a 12-week accumulated anomaly, it is possible for a location to have a non-zero DHW value when the HotSpot value is already less than one or even zero. Hence, at a status level of "No Stress" or "Bleaching Watch", it is possible for the corresponding DHW value to be greater than zero.

To receive an automated e-mail alert for any of the available reef sites, go to the subscription page, where you can also view and alter your selection(s) or unsubscribe from the e-mail list.

Your report of any bleaching observations (including observations of no bleaching) will be greatly appreciated. Bleaching observations can be entered on the NOAA/ReefBase Collaborative online bleaching report form.

Should you have any questions or feedback on the Satellite Bleaching Alert system, please send e-mail to _NESDIS_CoralReefWatch@noaa.gov.

Coral Reef Watch Satellite Coral Bleaching Monitoring
Home | HotSpots | DHWs | Coral Bleaching Virtual Stations | Satellite Bleaching Alerts

Contact the NESDIS Coral Reef Watch Team
Coral Bleaching Report Form | Request to Add a Reef Site | Comments and Suggestions

Other Related Links:
Coral Reef Watch | CoRIS | Coral Reef Conservation Program

Last Modified Aug. 8, 2008 (jw)

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