>>14138287The CO2 effect isn't negligible, but as I keep saying, many factors must be taken into account. The approach "low CO2 - bad for plant, high CO2 - good for plant" is ridiculously 1-dimensional.
1. Martian solar input (586.2 W/m^2) is lower than ours (1361 W/m^2)
2. Hence lower black body temperature emitted by the surface of the Mars (210K vs 254K)
3. Energy is proportional to T^4, so Mars only puts out 30% of the Earth’s infrared radiation. That alone, even on Earth, would reduce the greenhouse effect to only 10C instead of 33.
4. Also: water vapour, which is much less abundant on Mars, and it's responsible for a huge chunk of warming on Earth.
5. Still, this is very much an incomplete summary.
