Figure 1. Based on Winton’s¹² (WN) Fig. 1, where mean global and Arctic temperature change as well as Arctic amplification factors are presented for a doubling of carbon dioxide (CO₂) equilibrium experiment based on twelve climate model simulations from CMIP4 (first three columns).

Note that the original figure presented respective standard deviations, whereas here we present the 90% confidence interval ranges. The fourth column of data is a Ratio of Means definition of Arctic amplification with model spread calculated using the methodology presented in Fieller¹⁹ as opposed to the Mean Ratio approach employed by the original authors (column 3).