ReefTemp
ReefTemp is a collaborative project between the Great Barrier Reef Marine Park Authority (GBRMPA), CSIRO Marine Research, and the Bureau of Meteorology. ReefTemp is the first sea-surface temperature monitoring and mapping product in Australia tailored specifically for coral bleaching and builds on pioneering work done by the National Oceanic and Atmospheric Administration (NOAA). Unusually high sea surface temperatures (SST) trigger coral bleaching events and their frequency and severity will increase under future climate change scenarios.
At the broader scale sea temperatures are monitored using the Hotspot and Accumulated Heat Indices products available from the National Oceanographic and Atmospheric Administration (NOAA), along with local weather station data. ReefTemp has been tailored specifically to the Great Barrier Reef to provide now-casting of bleaching risk at a much finer spatial scale, enabling temperatures to be monitored at the scale of an individual reef.
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| ReefTemp can detect sea surface temperature and coral bleaching risk at the scale of an individual reef |
Maps of coral bleaching risk are produced in ReefTemp by presenting thermal stress indices (SST, SST anomaly, Degree Heating Days, and the Heating Rate). These indices are calculated by comparing remotely sensed daily temperatures to long-term averages. For each stress index, estimates of bleaching severity are presented in the ReefTemp interface as a colour gradation of light blue to dark red.
Early warnings of bleaching risk are a critical component of the Early Warning System of the Coral Bleaching Response Plan. When responding to bleaching events, the GBRMPA, partner agencies, researchers, and tourism operators use this tool to fine-tune monitoring, focus research efforts, and increase the effectiveness and efficiency of impact assessment programmes.
The GBRMPA has been working closely with the Predictive Oceans and Atmosphere Model Australia (POAMA) group at the Bureau of Meteorology on forecasting unusually high sea-surface temperatures months in advance. The POAMA group now produces experimental Great Barrier Reef and Coral Sea forecasts of sea-surface temperature on their research website. This product complements ReefTemp's daily updates by assessing the likelihood that temperatures will exceed bleaching tolerances one to three months in advance.
Related products are currently being developed that will improve our ability to predict bleaching risk between years / summers and better understand the relationship between thermal stress and bleaching severity. These are a result of ongoing collaborations with the Bureau of Meteorology and CSIRO Marine Research and will be made available soon.
ReefTemp, a more detailed project description, technical reports, and contact information for project managers can be viewed at http://www.cmar.csiro.au/remotesensing/gbrmpa/ReefTemp_application.htm


