That's ridiculous, of course you need a baseline for any sort of evaluation. Your comment implies any sort of warming, regardless of absolute levels, is bad.
Ok, then, how about this. The baseline is 0 degrees, because that is the lowest that temperature can be.
Would that be a fair baseline?
sorry for not being clear enough. I meant that the speed of warming is of interest here. That speed is independent of the baseline chosen. And that speed is what is worrying.