The NOAA Coral Reef Watch (CRW) heritage near real-time twice-weekly global 50km satellite coral bleaching heat stress monitoring products were operational at NOAA until April 30, 2020, when they were officially retired, and succeeded by CRW's next-generation operational daily global 5km coral bleaching heat stress monitoring product suite (https://coralreefwatch.noaa.gov/product/5km/index.php). The heritage 50km products served the U.S. and international coral reef communities for more than 20 years (1997-2020) as the only global early-warning system of coral reef ecosystem physical environmental changes. These near real-time products successfully and accurately monitored and predicted all major mass coral bleaching events observed globally since 1997, while also providing other critical information to users, especially during times of high heat stress. They helped resource managers, scientists, decision makers (including elected officials), and the public monitor climate impacts to reef ecosystems worldwide; enhance understanding of links between environmental conditions and ecosystem impacts; assess when reefs were vulnerable or resilient to climate change and its impacts (especially bleaching); and prepare and prioritize resources to implement timely, effective protective responses and adaptation actions (including restoration efforts), helping improve coral reef management and regulation in a warming world. With the retirement of the twice-weekly global 50km satellite coral bleaching heat stress monitoring products, NOAA CRW is still providing an archive of the 50km data and images for the following products: Sea Surface Temperature (SST), SST Anomaly, Coral Bleaching HotSpot, coral bleaching Degree Heating Week, Bleaching Alert Area, monthly and annual composites of the 50km products, and the 50km Virtual Stations. The 50km monthly mean satellite-only nighttime SST climatologies for all 12 months, and the maximum of those monthly mean climatologies are also available. Archived 50km data and images are available at https://coralreefwatch.noaa.gov/product/50km/.
The NOAA Coral Reef Watch program seeks to fully utilize space-based sea surface temperature (SST) observations combined with in-situ data to continually monitor for early indications of thermally-induced coral reef bleaching worldwide.
All products mentioned in this metadata file are accessible at https://coralreefwatch.noaa.gov/product/50km/.
Ground Condition
Not intended for legal use. Data may contain inaccuracies due to cloud cover and/or other reasons.
NOAA, NESDIS/STAR/SOCD Coral Reef Watch, NCWCP, E/RA3, 5830 University Research Court
The accuracy of the NOAA Coral Reef Watch Twice-weekly Global 50km Satellite Coral Bleaching Heat Stress Data and Products depends on the accuracy of the source dataset. The twice-weekly global 50km satellite SST, used for deriving the SST Anomaly and coral bleaching heat stress monitoring products (Coral Bleaching HotSpot, Degree Heating Week, and Bleaching Alert Area), was a satellite-based nighttime ocean temperature analysis. The SST for earlier years (before February 1, 2016) was derived from measurements by the Advanced Very High Resolution Radiometer (AVHRR) sensors onboard NOAA's Polar-orbiting Operational Environmental Satellites (POES). Each twice-weekly SST analysis was based on data from one AVHRR sensor onboard a single POES. As of February 1, 2016, however, the twice-weekly 50km SST analysis was based on NOAA's operational daily global 5km Geostationary-Polar-orbiting (Geo-Polar) Blended Nighttime-only SST Analysis. Note: the accuracy of the twice-weekly global 50km satellite coral Bleaching Alert Area product depends on the accuracy of CRW's twice-weekly global 50km satellite coral bleaching Degree Heating Week and Coral Bleaching HotSpot products, which, in turn, depend on the accuracy of the twice-weekly global 50km satellite SSTs and bleaching threshold SSTs. Evaluations of the performance of the twice-weekly global 50km satellite products throughout the years have shown that these products demonstrate remarkable success in detecting, monitoring, and predicting all large spatial scale mass coral bleaching events. Polar Orbiting Environmental Satellite (POES) AVHRR-SST values used for creating CRW 50km SST analysis fields were accurate to within 0.5 degree Celsius and adjusted by in-situ buoy observations to best approximate SST at the depth of one-meter. However, when producing a complete, gap-filled SST analysis with global coverage, estimation of SST at the pixels covered by cloud may occasionally reduce the accuracy of SST at these pixels.
none
There is no spatial data gap existing in this dataset.
Users are referred to the following guide on AVHRR-derived sea surface temperature: Goodrum, G., K.B. Kidwell, and W. Winston, 2000, NOAA KLM USER'S GUIDE. U.S. Department of Commerce, National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service, National Climatic Data Center, Climate Services Division, Satellite Services Branch, FOB3, Room G227, E/CC33, 5200 Auth Road, Suitland, MD 20746-4304, USA. Users are also referred to the NOAA/NESDIS Geo-Polar Blended SST website (https://www.star.nesdis.noaa.gov/sod/mecb/blended_validation/sst_monitor.php).
The NOAA CRW twice-weekly global 50km Virtual Stations product was partially derived from this Bleaching Alert Area product.
The NOAA CRW twice-weekly global 50km Virtual Stations product was partially derived from this Degree Heating Week product.
The NOAA CRW twice-weekly global 50km Virtual Stations product was partially derived from this Coral Bleaching HotSpot product.
The NOAA CRW Twice-weekly Global 50km Satellite Coral Bleaching HotSpot and coral bleaching Degree Heating Week products were derived from this Sea Surface Temperature (SST) product.
The level of coral bleaching heat stress at a data grid presented in the Bleaching Alert Area product is determined by the values of Degree Heating Week and Coral Bleaching HotSpot at the data grid. A Degree Heating Week is calculated as the accumulation of Coral Bleaching HotSpots over 12 consecutive weeks. At each satellite pixel, a coral bleaching threshold SST value is subtracted from the SST value to produce a Coral Bleaching HotSpot. See the CRW web site at https://coralreefwatch.noaa.gov/product/50km/ for more information.
NOAA makes no warranty regarding these data, expressed or implied, nor does the fact of distribution constitute such a warranty. NOAA cannot assume liability for any damages caused by any errors or omissions in these data, nor as a result of the failure of these data to function on a particular system.
NOAA Coral Reef Watch Twice-weekly Global 50km Satellite Coral Bleaching Heat Stress Data and Products web site
NOAA Coral Reef Watch Twice-weekly Global 50km Satellite Coral Bleaching Heat Stress Data and Products data
NOAA Coral Reef Watch Twice-weekly Global 50km Satellite Coral Bleaching Heat Stress Data and Products images
Time Series Data for NOAA CRW's Twice-weekly Global 50km Virtual Stations
Time Series Graphs for NOAA CRW's Twice-weekly Global 50km Virtual Stations
The product in various formats may be downloaded from the CRW web site or obtained directly from the distributor.
