There has been a lot of CW discussion on climate change. This is an article written by someone that used to strongly believe in anthropogenic global warming and then looked at all the evidence before arriving at a different conclusion. The articles goes through what they did.
I thought a top-level submission would be more interesting as climate change is such a hot button topic and it would be good to have a top-level spot to discuss it for now. I have informed the author of this submission; they said they will drop by and engage with the comments here!
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Notes -
The day & night is relevant here. The sunlight has the potential to heat the ground to over 100ºC (212ºF). The reason it doesn't get that hot is because the ground conducts heat to the air, which then convects upwards. So the sunlight, during the day, has the power to heat the surface far above the blackbody average.
Then, you just need to compare temperatures at differing elevations to see that the adiabatic lapse rate has a real effect on the temperatures you find there. Compare bottom of grand canyon to top of grand canyon to high up on a mountain-top. The air pressure at all of these levels is, of course, higher than the air pressure would be without an atmosphere, which is zero.
So we know for a fact that gravity causing increased air pressure results in higher temperatures than those found at lower air pressures. This is observable, empirical, and irrefutable. I wrote some more detail about the lapse rate here: https://www.themotte.org/post/960/the-vacuity-of-climate-science/205320?context=8#context .
The atmosphere, thus-warmed during the day, then prevents the night-time temperatures from getting as cold as they do without an atmosphere (-100ºC on the moon), much like how a blanket works.
The net effect of the above is evidently that it is cooler during the day than without an atmosphere, warmer at night than without an atmosphere, and the 'average' temperature is overall higher than without.
This is a misunderstanding. Blackbody temperatures are often reported as global averages, which is why the moon daytime high is above the "blackbody temperature" -- because the average blackbody temperature includes the night side. You can do the Stefan boltzmann calculation for the day side of the moon. You will find that the daytime blackbody temperature is about 400k, which is very close to the measured daytime surface temperatures.
This is the part that you still have not shown. I would appreciate it if you would do just the thermodynamics 101 energy balance calculation to show the effect.
A packet of air on the surface on the day side will perhaps pick up energy from the surface. This warms the air, but also cools the surface. If this packet of energy is moved to the night side, it will deposit it's energy onto the surface; the surface will warm and the packet will cool. This tends to equalize temperatures between day and night sides but cannot provide a net increase in temperature (of sum of day and night side) due to conservation of energy. The global average temperature is still blackbody (day side being warmer than global average blackbody and the night side being colder).
No, the blanket analogy is invalid. If the gas is transparent to radiation, then it provides no barrier to radiative heat transport from the surface. In fact, the presence of a gas would reduce the insulating effects because it provides a conductive/convective path away from the surface (vacuum being the best insulator).
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