We’ve discussed this before…but the question for that hypothesis is “how does CC change the laws of thermodynamics and atmospheric dynamics?”
The short answer is…”they don’t”. CC doesn’t all of the sudden mean PV = nRT is no longer true. It just means our T is higher. Same with other equations.
Models are simply running these equations based on data input. The data being input is real time data so it should already account for the current conditions of 2023. If we input a bunch of data from 1970, you’d get a colder look but still a forecast that resembles what happened back then. Now if you’re running a climate model, you’d want to account for more CO2 each year since that will affect warming once you go out far enough. But this won’t be relevant on an operational short or medium range model. Whatever minuscule CO2 increase happens over the course of a 15 day OP run is not enough to cause meaningful temperature change.
Older/Obsolete models used to have trouble with dynamical/latent cooling which is why we likely saw more positive snow busts when they thought it would be +1C aloft…now, models have gotten a lot more skilled (a lot more vertical layers are present in models now too which will catch pockets of higher lift that potentially could have been missed by their primitive predecessors), and when they say it will be +1C aloft, they are closer to correct since they are better at already accounting for dynamical and latent cooling than older versions of models.