Figure 4. Constrained estimates of ECS suggested by interannual
(\(\psi\)) and decadal (\(\sigma_{b}\)) temperature variability metrics.
The original Cox et al. (2018a) constraint is shown for comparison.
Error bars indicate 66% confidence intervals. ECS values for each GCM
are also shown (black) to illustrate model spread. The IPCC 66%
confidence interval is shaded gray.