Fig. 4
From: Elevated CO2 degassing rates prevented the return of Snowball Earth during the Phanerozoic
Model predictions. Model of Mills et al. (ref. 40), with relative degassing rate set proportional to PALEOMAP subduction zone length. a Model solar flux. b Relative atmospheric CO2 concentration shown against suggested thresholds for glaciation (red bars, see text). c Glaciation paleolatitude, as in Fig. 1. d Modelled global average surface temperature. For model runs, black lines show standard run, as in the COPSE model (see text), blue lines show twofold enhancement of terrestrial weathering (W = 2), representing a lower bound under potential glaciation trigger events. Orange lines show a twofold suppression of weathering rates (W = 0.5) for contrast
