The Gravito-Thermal Greenhouse Effect...

UPDATE May 2021. I've boiled this all down to a simple explanation based on common sense, basic maths and a rudimentary knowledge of the Gas Laws.

Please read my post Acceleration ≈ Gravity
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... explained, again, over here.

The author of the paper has been much maligned, by alarmists and even by other sceptics.

But it seems perfectly plausible to me. It ties in with other things that we know, or at least are widely accepted as correct:

1. The high pressure and temperature at the centre of gas giants, even if they consist mainly of H and He. If big enough, this triggers nuclear fusion and they are called 'stars'. Then there is the usual downward temperature and pressure gradient as you move out through the atmosphere.

2. The fact it's colder the higher up you go in the mountains (aka 'adiabatic lapse rate'), and hotter at the bottom of the Dead Sea Depression, partly because it's below sea level.

3. The lapse rate is very similar on Venus and Earth, even though one atmosphere is mainly CO2 and the other mainly N2.

4. Vortex tubes can separate air into very hot and very cold streams by using centrifugal force i.e. simulated gravity.
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Maybe it is nonsense, but it would be *very easy* to test if you had a couple of $ million to spare. They could divert a tiny part of the budget they waste on The Hunt For Dark Matter, for example.

Method 1

a. Take a very large object like an old cooling tower, gasometer or a lighthouse.
b. Insulate it top, bottom and all the way round so that warmth can't get in or out.
c. Place pressure and temperature sensors inside at top and bottom.
d. Seal the object and wait a few days, the longer the better.
e. See what happens to the temperatures at top and bottom.

IF the explanation is correct, then the air at the bottom will be warmer than the air at the top by about 0.1C for every ten metres height - even though the air is not being warmed from below.

IF the theory is nonsense, then something else will happen. Maybe the simplistic 'heat rises' rule wins out and the air at top will warm up and air at bottom will cool down.

Method 2

a. Take a giant centrifuge.
b. Fill a large tube, the longer the better, with air at the average temperature and pressure of our troposphere ('cold' and 'low' respectively). Seal tube.
c. Attach one end of tube to centrifuge and spin it round as fast as you can.
d. Measure pressure and temperature at in the middle (spinning slowly = low gravity = top of atmosphere) and at the end (spinning quickly = high gravity = surface of Earth).
e. Stop the centrifuge again, and check to see whether temperature and pressure return to what you started with (to eliminate any element that might arise from friction between air and surface of tube).
f. As a bonus, you can try adding or removing H2O, CO2 or CH4 to see whether it makes a difference.

IF the explanation is correct, then while it is spinning, the air in the middle will be at a lower temperature and pressure than what you started with, and the air at the end will be higher temperature and pressure.

IF the theory is nonsense, then something else will happen, like the temperature and pressure remaining the same throughout.

I, for one, would love to see them do this. I will eat my hat if these experiments disprove the explanation.