A global analysis of coral bleaching over the past two decades

• DOI: 10.1038/s41467-019-09238-2
• Publication Date: 2019-03-20T11:04:20Z
• Authors: S. Sully; D. E. Burkepile; M. K. Donovan; G. Hodgson; R. van Woesik
• Keywords: Coral bleaching; Anthozoa

Thermal-stress events associated with climate change cause coral bleaching and mortality that threatens reefs globally. Yet patterns vary spatially temporally. Here we synthesize field observations of at 3351 sites in 81 countries from 1998 to 2017 use a suite environmental covariates temperature metrics analyze patterns. Coral was most common localities experiencing high intensity frequency thermal-stress anomalies. However, significantly less variance sea-surface (SST) Geographically, the highest probability occurred tropical mid-latitude (15-20 degrees north south Equator), despite similar thermal stress levels equatorial sites. In last decade, onset has higher SSTs (∼0.5 °C) than previous suggesting thermally susceptible genotypes may have declined and/or adapted such remaining populations now threshold for bleaching.