Stop the madness. Again, the experimental chamber can control all the variables, including making changes that emulate what we observe in the atmosphere. It won't be 100% perfect, but it does allow us to change those variables in order to produce viable tests, in conditions we won't find in the real world.
Or, not. Unless, of course, you claim to know
exactly where
all the tipping points are, in which case you can collect your Nobel Prize next year.
Just what I always wanted: More bull****.
25% of the land mass in the Northern Hemisphere is (still) permafrost. Not much has melted yet. Once it does start to really melt, it could unlock up to 150 billion tons of CO2. In comparison, the US emitted around 5.4 billion tons of CO2 in 2017. Even if only half that amount of permafrost melts, the impact could be immense.
Made up numbers about methane, please, the numbers came from the American Chemical Society.
https://www.acs.org/content/acs/en/climatescience/atmosphericwarming/climatsensitivity.html
And no, methane is quite a bit less effective as a greenhouse gas than CO2, at least according to the ACS.
25% of the land mass in the Northern Hemisphere is (still) permafrost.
I will check, but that seems high.
*bzzt* wrong, we can get a pretty good idea of normal temperatures, before we started slamming the atmosphere with GHGs. (And no, don't give me your usual bull**** about "but the resolution is different!" We know what's happening, and it is not good.)
Let't start with I can describe 1 variable that the above chamber cannot control, you said they can control them all.
The population inversion of a partial pressure gas in a 30,000 meter high atmosphere, You cannot control or emulate that in a 5 meter high tank.
Why is that important? because once a CO2 molecule absorbs a 15 um photon, it must wait about 40 to 50 milliseconds to receive another one.
A heat source capable of emitting 15 um photons could emit one about every 50 picoseconds.
400 ppm CO2 provides a mean free path of about .25 mm, so within under one second the above tank would hit a population inversion.
I do not have to know where the tipping points are, only that we appear to be at the upper rail already.
We do not have a good idea on the normal temperature swings, and Marcott had an average temporal resolution of 120 years, and so might not so the 1978 to 1998 warming.