...or you could just do the calculations for Mars, the same way we do for Earth:
http://www.atmos.washington.edu/2002Q4/211/notes_greenhouse.htmlWe calculated the effective radiating temperature for Earth in class, as summarized in the above notes. Let's do the same for Mars.
Here is the information we have:
the albedo on Mars is A = 0.22,
and the solar flux reaching Mars is equal to 593 W/m2.
Gosh Paul, "Solar radiation incident
on the Earth's disk [is]
(1370 Watts per square meter)...."
That difference, between 1370 and 593 Watts, might be a factor to consider also.
...as well as the huge difference in atmospheric pressures, for each planet.
===
But,
do you know for sure that the CO2 on Mars hasn't made Mars warmer (than Mars would be without the CO2) ...
like greenhouse gases do...
This effective temperature of 255 K is the temperature the Earth's Surface would have if it didn't have an atmosphere. It would be awfully cold! In reality, the Earth's surface temperature is closer to 288 K (15 °C, 59 °F). This difference of 33 K is the magnitude of the greenhouse effect.
...
here on Earth.
~