MONITORING AND CALIBRATING SEA SURFACE TEMPERATURE ANOMALIES WITH SATELLITE AND IN-SITU DATA TO STUDY EFFECTS OF WEATHER EXTREMES AND CLIMATE CHANGES ON CORAL REEFS

s anomaly, as recorded in NOAA global sea surface temperature ip data bases averaged over the broadest time and space scales, high resolution satellite data, and in-situ measurements in the Caribbean showed that high resolution data was within around 0.2 degrees of the real value, but underestimated it increasingly as temperature rose. In contrast, low-resolution data for the Caribbean systematically underestimated temperatures by up to several degrees, in a sitespecific manner. The bias appears greatest for large or high islands and for continental shorelines where topographic thermal convection effects cause high generation of small clouds, which cause satellite temperature measurements to be too low. Although low-resolution data are adequate to identify large-scale temperature anomalies in the Indo-Pacific, they miss small, intense, transient thermal anomalies and therefore underestimate actual thermal stress. Despite these limitations, combining remote sensing data and field observations suggests that current climatic extremes are adequate to trigger coral bleaching, placing coral reefs worldwide at severe risk from any further global warming.