I want to roughly use the same formula to extrapolate future temperatures based on this same CO2 increase as the accompanying document suggests: Temps using CO2. The issue is the constants used... because if the same formula is used, then at year 2052, the temperature would be doubled which is obviously not realistic.
So my question is: what coefficients should be used in this: $T=\left(1+\exp(ct)\right)$ formula, where $c$ is a constant ($0.0222$ I would think) and $t$ being a some measure of time.
Or is there a better formula to use which correlates exponentially increasing CO2 with increasing temperatures?