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Old 08-01-2021, 12:13 PM

JA is offline
Join Date: Oct 2016
Location: Melbourne, Australia
Posts: 2,026
Originally Posted by yusufcam View Post
what you're saying makes sense but its hard to understand in light of the distances from the Sun (at least at this point for me).

could atmospheric composition outweigh density to that degree? They reckon that Mars atmospheres density is equivalent to being at a 35km height above ground level on earth, and the temperature at that height is about -54 C.

I wonder if the actual air temperature is affected by the radiant heat from the planet rather than atmosphere in some way that gives those livable temperatures they have been able to record.

Just curious how it would work
There is a huge difference in the atmospheric pressure at the surface of Mars (~0.6 kPa) compared to that of the Earth (~101.3kPa), i.e: ~170x greater atmsopheric pressure on Earth, which (under certain assumptions) relates also to differences in density factoring different temperatures in to the mix, via the Ideal Gas Law. As to the 35km question: If you travel high enough in our atmosphere you will reach a similar pressure.

Air temperature and surface temperatures are effected by radiant heat transfer. There is a good representation of this by a Scientist by the name of Trenberth (I think it was) who quantified the Earth's energy balance. I will see if I can find a link later.

EDIT added Trenberth et al 2009 - Earth Energy Balance....
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Last edited by JA; 08-01-2021 at 12:25 PM. Reason: added image
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