Daily 5-km Satellite Coral Bleaching Thermal Stress Monitoring
(Version 2, experimental products)
NOAA Coral Reef Watch is pleased to announce the release of its new Daily 5-km Satellite Coral Bleaching Thermal Stress Monitoring Product Suite. The 5-km products are accessible directly below, from the left navigation bar, and throughout this website. Access to our heritage suite of operational 50-km satellite monitoring products will still be possible for the next several months. We encourage all of our users to look over the new 5-km products and provide feedback to us at coralreefwatch@noaa.gov.

Click on buttons below image to change parameter; click on image to view larger, tiled images.

Current Regional Images
Alert Area (7-day max):  Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR
Hotspot:  Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR
DHW:  Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR
SST:  Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR
SST Anomaly:  Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR
4-Month Outlook (60%) Global | 45ns | East | West | Pacific | Coral Triangle [big] | Caribbean [big] | Florida | Hawaii | GBR

NOTE: New CRW color palettes were developed and implemented in this version of the 5-km products. (Click here to view images using CRW's old 50-km color palette.) We welcome user feedback about the new color palettes. (This includes letting us know if you notice any 5-km product images that are missing the new palettes.)

Archived Data and Images
(Degree Heating Week, Alert Area, and others available since 3 June, 9 June, and 12 March 2013, respectively)

Global and Regional Images:
60x40-degree tiled images (see description of tiles)
Data Files (netCDF format):     Alert Area (7-day max) | Alert Area (daily) | HotSpot | DHW | SST | SST Anomaly


Product Suite Description

The NOAA Coral Reef Watch (CRW) experimental daily global 5-km (0.05 degree) satellite coral bleaching thermal stress monitoring product suite presented here is a next-generation version of the operational twice-weekly 50-km (0.5 degree) monitoring product suite. The high-resolution 5-km suite is based on the NOAA/NESDIS operational daily global 5-km Geo-Polar (geostationary-polar-orbiting) Blended Night-only SST Analysis and currently includes sea surface temperature (SST), SST Anomaly, Coral Bleaching HotSpot, Degree Heating Week (DHW), and Bleaching Alert Area products, matching the core operational 50-km satellite products. In February 2015, CRW also added a new Virtual Stations/Gauges product that is based on this 5-km product suite and CRW's Coral Bleaching Thermal Stress Outlook product and is much more comprehensive than the heritage 50-km Virtual Stations product.

Improvements of the 5-km products over the heritage 50-km products are derived from:

  1. Next-generation SST Analysis

    1. Higher spatial and temporal resolutions and greater data density

    2. Higher SST quality with a next-generation SST algorithm

  2. New Climatology

    1. The climatology used for CRW's new 5-km Geo-Polar Blended Night-only products was produced using night-only values for the 28-year period 1985-2012 from the 4-km Advanced Very High Resolution Radiometer (AVHRR) Pathfinder Version 5.2 SST (PFV5.2) data set, an official NOAA climate data record. We used the 28-year period to produce 12 monthly mean climatologies. The 5-km climatological average values were bias-adjusted to match the 5-km SST data and re-centered to the time-center of our operational 50-km climatology to maintain consistency with our heritage 50-km products.

    2. In an attempt to preserve the interpretation of DHW values when predicting bleaching, while developing the 5-km product suite, we faithfully recreated the Maximum Monthly Mean (MMM)-climatology and HotSpot/DHW methodologies of the heritage operational 50-km products in such a way as to make each of the two product suites as similar as possible. The major differences between the 5-km and 50-km products lie in their different resolutions and in the methodologies used to create the individual pixel SSTs. These differences will almost certainly change the interpretation of the 5-km product suite for some regions when predicting bleaching. We are most interested to hear from users who notice any interpretive changes.

    3. Efforts are underway in NOAA/NESDIS presently, at the request of CRW, to reprocess the 5-km Geo-Polar Blended SST analysis. Applying the current SST algorithms to satellite measurements from the past will produce a consistent historical data set back to 1994 -- the start of the second-generation geostationary environmental satellite record. CRW will then produce a new climatology from this record and reproduce its 5-km products throughout that period. This will allow further validation to refine CRW's thermal stress monitoring algorithms and provide extended data sets directly from almost 20 years of geo-polar blended SST data.

This daily global 5-km coral bleaching thermal stress monitoring product suite provides service at or near reef-scales, allowing direct monitoring of 95% of global coral reefs and significantly reducing data gaps caused by cloud cover. The 5-km products now comprise the core of CRW's next-generation Decision Support System (DSS) for coral bleaching management. After further testing and evaluation of the 5-km product suite, CRW's operational 50-km product suite, which has provided 15 years of successful satellite-based monitoring of coral reef ecosystem environmental conditions to global reef communities, will be retired.

Version 2 of the 5-km product suite, presented here, was released on May 5, 2014. CRW's new 5-km Virtual Stations/Gauges were launched February 17, 2015. As noted above, the Version 2 5-km product suite is based on NESDIS' operational daily global 5-km Geo-Polar Blended Night-only SST Analysis, released in March 2013, and uses a new version of the 5-km climatology (available since April 2014).

SST variability is often considerably higher at the much finer 5-km spatial and daily temporal resolutions, when compared with CRW's 50-km twice-weekly SST. Due to resulting day-to-day fluctuations between stress levels in highly-variable locations, the single-day 5-km Bleaching Alert Area product does not consistently and adequately identify potentially harmful thermal stress levels, especially with regard to the impact of accumulated thermal stress. Rather than requiring users to examine the single-day 5-km Bleaching Alert Area product over several days, a 7-day maximum Bleaching Alert Area composite product, updated daily, was introduced in the Version 2 product suite. This 7-day composite product shows the maximum stress level that a pixel has experienced during the most recent seven (7) consecutive days. The data and images are dated on the last day of the 7-day period. Additionally, the 5-km 7-day maximum Bleaching Alert Area composite product is compatible with CRW's operational 50-km twice-weekly Bleaching Alert Area product. The 50-km Bleaching Alert Area product is actually based on a half-week (3 or 4 days) composite of 50-km SSTs, but with much less SST variability due to its much coarser spatial resolution.

Note that all other Version 2 products presented here are single-day products, updated daily. Images will be 1-2 days behind the current date, however, as data are processed in the early afternoon, U.S. Eastern Time using data from the previous day. For example, data processed on a Wednesday afternoon will include all observations made on Tuesday (independent of time zone) and will carry Tuesday's date.

For more technical details about the new 5-km product suite, see Liu et al. 2014.

Development of the next-generation 5-km product suite has been accomplished through a collaboration of NOAA Coral Reef Watch, the University of South Florida, NASA-Ames, the UNEP World Conservation Monitoring Centre, and the Cooperative Institute for Research in Environmental Science, with funding support from the NASA Biodiversity and Ecological Forecasting program, the NOAA Coral Reef Conservation Program, and the NOAA/NESDIS Ocean Remote Sensing Program. The 5-km product suite, which was featured in the NASA Applied Sciences Program's 2013 Annual Report, will undergo continuous improvements.

CRW will continue to produce the current operational 50-km product suite until the 5-km product suite becomes operational. As noted above, there will be some differences between the two product suites in certain areas, and user discretion is advised. We expect that the 5-km product suite will be more accurate due to the improved data quality, density, spatial and temporal resolutions, and climatology.

CRW Operational Twice-weekly 50-km Product Suite