12-13-2014, 12:21 AM
(12-12-2014, 10:50 PM)Cray Wrote: I was kicking around an alternate history for a roleplaying session and got to thinking about swelling up Mars a bit, like in Harry Turtledove's "A World of Difference."
The idea is that plus-sized Mars would still be red and lifeless (?), so it wouldn't alter human history. (Lots of religions depend on Mars being red.) However, it'd be larger (surface gravity ~0.8G) and have a thicker atmosphere (~0.7 bar.) If that atmosphere was 80% nitrogen and 20% carbon dioxide, what would that do for the Martian climate?
Are there any handy planet climate modelers to figure out a planet's average temperature based on pressure, CO2 levels, and insolation?
Assuming the Martian albedo of 0.25 remains unchanged (it likely would increase, because of the increased size of the polar caps, though this would be offset somewhat by open bodies of liquid), a quick BOTE calculation gives a mean surface temperature of 276.587 K, or just above the freezing point of water.
Radtech497
"I'd much rather see you on my side, than scattered into... atoms." Ming the Merciless, Ruler of the Universe