Summary of average RMSE across the model experiments a) Eocene runs for CO2 using 4x pCO2 (Table 3), ice runs contain no ice with pCO2 of 560 ppmv, Eocene paleogeography runs (Table 3) b) Oligocene runs for pCO2 using 2x pCO2, ice runs containing the model prescribed ice sheet with pCO2 of 560 ppmv, and Oligocene paleogeography runs c) is the difference model outputs between the Oligocene and Eocene runs. (Table 3). The x axis headers correspond as follows: CO2 distinguishes the proxy-model comparison based on pCO2 changes, ice for the with and without an ice sheet, and geo for the model runs with paleogeographic changes. MAT and SST correspond to either air or sea surface temperature comparison Mean is the orange line with outliers as dots. Dots are outliers with both from the GFDL CM2.1 model. Blue line is the ensemble mean from the pCO2 scaling.