Figure 4

Comparison of oxygen isotope temperatures (E) with climate and tectonic proxy data. (A) Occurrence and latitudinal extent of glaciogenic sediments²⁰; (B) estimated δ¹⁸O_sw (this study); (C) atmospheric pCO₂²¹; (D) crustal accretion rate²² compared with combined phosphate and carbonate δ¹⁸O paleotemperature (low-latitude, Locfit regression and 5-myr averages); (E) Low-latitude phosphate and carbonate δ¹⁸O paleotemperatures calculated by correcting seawater δ¹⁸O for ice volume (iceV) and latitude (lat). Locfit regression (α = 0.05) with 95% Cl calculated for combined carbonate and phosphate δ¹⁸O paleotemperatures. Paleozoic clumped isotope paleotemperatures (clumped T) from Henkes et al.²³ and Barney and Grossman²⁴. Also shown are TEX₈₆ paleotemperatures using the TEX₈₆^H-SST calibration^16,17. Geologic time scale abbreviations same as in Fig. 1. Warm events: La Landovery, Lo Lochkovian, FF Frasnian–Famennian, PT end-Permian and early Triassic, To Toarcian, CT Cenomanian–Turonian, PETM Paleocene-Eocene Thermal Maximum, EECO Early Eocene Climatic Optimum.