Temporal relationships between ocean warming and coral cover decline. the blue and pink bars show the average annual temperature anomalies for land and sea from a 1961-1990 baseline [based on the Hadley Centre Climatic Research Unit Temperature 4 (HadCRUT4) data set], and the black line shows the average annual coral-reef sea-surface temperacture [from the Hadley Centre Global Sea Ice and Sea Surface Temperature 1 (HadISST1) data set]. The orange line shows the temporal trend in absolute mean Caribbean coral cover (based on a regional meta-analysis). Figure adapted from Gardner et al. (2003) and Lough et al. (2018.