Predictions for the future of coral reef are largely based on thermal
exposure and poorly account for geographic variation in biological
sensitivity and resistance to thermal stress. Based on the ratio of
thermal exposure and sensitivity, geographic variability of coral
resistance was estimated during the 2016 global-bleaching event.
Exposure was estimated as historical cumulative excess summer heat (CTA)
and a multivariate index of SST, light, and water flow (CE). Site
sensitivity was estimated for 226 sites using coordinated bleaching
observations. Site resistance was evaluated by 128 possible models for
the influences of geography, historical SST variation, coral cover, and
number of coral genera. Most factors were statistically significant but
the strongest factor was geography - Coral Triangle having higher
resistance than non-Coral Triangle sites. Consequently, future
predictions of thermal stress will need to account for strong geographic
differences in acclimation/adaptation.