Time distribution of when the model runs enter a runaway warming phase for Venus-like instellation, hypsometry, and α = 0.65. Mass-dependent water ingassing is shown on the left, and surface-dependent ingassing is shown on the right. Runaway warming is defined as the first instance the model’s surface temperature exceeds 400 K and never returns to temperate conditions. The data is divided into 50 equal-width bins (light blue bar plot) where the number of runaway models are divided by the total number of runs to calculate the probability density estimate of when runaway warming is more likely (y-axis). The median and mean are plotted as orange and yellow dotted lines, respectively. Even for optimistic albedo conditions, Venus-like planets that have imbalanced carbon cycles enter the runaway warming phase relatively early, before 2 Gyr.