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NOAA Coral Reef Watch

NOAA’s Coral Reef Watch (CRW) is a free online tool that provides a global analysis of sea surface temperature (SST) and outlooks to identify coral reefs that are at risk of bleaching. Coral reefs are very sensitive to temperature changes. When the ocean gets too warm, they begin to bleach (turn white) as the tiny creatures that live in coral reefs become stressed and leave, exposing the white skeleton.

CRW is a tremendous resource to coral reef managers, allowing them to better protect and manage the planet's most diverse aquatic resources. Coral reefs are often located in distant and remote regions, coral reef managers need satellite tools to help monitor the reefs. NCEI’s data plays a central role in supporting CRW, and the global coral reefs that this product monitors.

The CRW products use near-real-time and historical satellite SST measurements to determine the temperature threshold of coral reefs across the globe. Historical satellite measurements come from the NCEI’s Pathfinder Climate Data Record (CDR), a long term record of SST data from 1981–present. This record is an essential data input to CRW that serves as the baseline, or climatology, to measure daily differences. CRW products depend on these anomalies, or differences, to provide coral bleaching alerts.

Case Study

Review the Success Stories on User Engagement report from March 2016 for more detailed information about NCEI data applications in the reinsurance sector. The report showcases the NCEI’s datasets, which provide the long-term, high resolution baseline temperature record that makes this product possible. 

Related Products

NCEI’s Pathfinder Seas Surface Temperature (SST) Climate Data Record (CDR) is an essential input to the Coral Reef Watch (CRW) 5-km product suite. Without a long-term and high-resolution baseline temperature record, CRW would not be able to compute an SST anomaly that alerts coral reef managers to bleaching events. Without Pathfinder, the transition from the 50-km suite to the 5-km suite may not have been possible and reef managers would be lesser informed. As the world stands at risk of losing more coral reefs, the value of the CRW cannot be overstated.

Anne Rosinki, Rapid Response Manager 2014 & 2015, Hawaii Division of Aquatic Resources

Anne Rosinki, Rapid Response Manager 2014 & 2015, Hawaii Division of Aquatic Resources

“In 2015 Hawaii experienced a second coral bleaching event. We knew about this months before because of Coral Reef Watch … We were starting to see that temperatures were going to rise specifically in one area of the state along the western coast of Hawaii Island. We brought this to the managers at the Division of Aquatic Resources, and we actually used this to prioritize our monitoring and management strategies for that year.”