We could tell only that CO2 levels had stabilized, if they did. (They won't.)
The connection between that KNOWN and changes in global temperature are rather less certain, with a large element of doubt, as noted, the further one goes out. These models are amazingly complex, I've looked at them, many terms, many coefficients, some of which are with exponents, and the only way to contrive them is to try and ensure they "back predict" what we think has happened to date.