Figure 2.

Coral skeletal core records of heat stress. (a) μCT scans (dark/light shading = low/high density) reveal discrete high-density stress bands and partial mortality scars preserved within the skeletons of long-lived Porites corals. Characteristic signatures of heat stress are shown for the years with the most stress bands recorded (2016, 2015, 2010, 2002, and 1982) and the oldest stress band in our dataset (1877). Scale bars are 5 mm. (b) Verification of the timing of a stress band as January–March 2015 is confirmed by monthly dissepiment counts (yellow) superimposed onto a μCT image of the same coral. (c) Stress band proportion (black bars) in all cores from 1815 to 2017 and (d) 2000–2017. The red line in (c) indicates the number of cores in the dataset per year.