NOAA USING SATELLITE DATA TO MONITOR HEAT STRESSES ON CORAL REEFS

February 25, 2003 — NOAA scientists are using satellite data to monitor the long-term effects of heat stresses on several coral reefs throughout the world. While the scientists have been monitoring the stresses for some time, the NOAA National Environmental Satellite, Data, and Information Service is now providing an operational product called “Degree Heating Week”. (Click NOAA satellite image for larger view of Degree Heating Weeks for the past 12 weeks taken Feb. 25, 2003. Click here for DHW.)

“Degree Heating Weeks have been available experimentally for some time,” said Dr. Alan Strong, coordinator of Coral Reef Watch at NOAA Satellite and Information Services. “Turning operational means that coral reef managers and stake holders will now have up-to-date, accurate, and reliable information on the status of their reefs and may be able to take active measures to prevent further damage if their site has a high DHW rating.”

Using satellite-derived information, DHWs continuously monitor the cumulative thermal stress of several coral reefs throughout the globe, including Australia’s Great Barrier Reef, Galapagos, the Bahamas and others. The extent and acuteness of thermal stress, key predictors of coral bleaching, contribute to coral reef degradation worldwide.

Coral reefs compose a large and integral part of the coastal ocean, supporting a variety of sea life and providing resources of significant economic importance. Coral bleaching occurs as coral tissue expels zooxanthellae, a symbiotic algae essential to coral survival that resides within the structure of the coral. Bleaching is induced by high water temperatures.

A Degree Heating Week is designed to indicate the accumulated stress experienced by coral reefs. For example, if the current temperature of a reef site exceeds the maximum expected summertime temperature by one degree Celsius, then the site receives a rating of 1 DHW. If the current temperature at the site is two degrees Celsius above the maximum expected summertime temperature or one degree above for a period of two weeks, the site would receive a rating of 2 DHWs, and so on.

With the operational product, NOAA Satellite and Information Services will provide continuous technical support on a 24-hour, seven-day basis, and will maintain a Web site which will be updated twice a week.

NOAA Satellite and Information Services is the nation’s primary source of space-based meteorological and climate data. NOAA Satellite and Information Services operates the nation's environmental satellites, which are used for weather and ocean observation and forecasting, climate monitoring and other environmental applications. Applications include sea-surface temperature, fire detection and ozone monitoring.

NOAA Satellite and Information Services also operates three data centers, which house global data bases in climatology, oceanography, solid earth geophysics, marine geology and geophysics, solar-terrestrial physics, and paleoclimatology.

NOAA is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of the nation’s coastal and marine resources. NOAA is part of the U. S. Department of Commerce.

Relevant Web Sites
NOAA’s Degree Heating Week

NOAA Satellite and Information Services

NOAA's Coral Reef

Media Contact:
Patricia Viets, NOAA Satellite and Information Services, (301) 457-5005