Figure 5.

Predicted paleotemperature mapped onto reef bathymetry. Predicted temperatures using isotopic thermometer models, which are variations of the Epstein paleotemperature equation^24,25 interpolated over the reef bathymetry using the sampled δ¹⁸O data. The numerals on the grey contour lines on the map indicate depth in m. Because the models are linear, the colour bar gradient and range is identical for all model results, however the absolute scaling varies. The two temperature colour bars above the map are identical. The predicted temperature scales are calculated from: (A) late Holocene Halimeda from the northwest Caribbean³⁴ using Grossman and Ku⁶⁴; (B) Miocene Halimeda reef material²¹ modified from Böhm et al.⁶⁷; (C) Porities sp. aragonite collected from the Galapagos⁸¹.