Oh, I’m sure they’re well aware of it.
But IIRC the mission statement of the IPCC is that man made climate change (specifically global warming) is happening and that it is bad.
So guess what they find?
Begged question city, huh.
There are a lot of parameters which can only be guessed. The simulators we have to date cannot literally dig down to first physical principles — we have insufficient data for that. So we basically have a display of a faked puppet show, with fudge factors galore.