Mega-Mars

[radtech497]

So...if you trade out 10-15% of the nitrogen in an 80 nitrogen/20 CO2 atmosphere for methane, what's that do for temperatures on Mega-Mars? Methane's a much more potent greenhouse gas.

Actually, it seems like that much methane could make the planet quite a bit warmer and ruin my Eskimos-in-space alternate history.

Again, assuming the planetary albedo remains the same, an atmospheric methane concentration of 10% raises the mean surface temperature to 520.048 K (much too hot for water, and hotter even than Venus). A 15% concentration warms the surface even more, to 545.066 K.

As you noted, methane is a potent greenhouse gas.

Radtech497