Apart from the fact that all of this is hugely scary to me, there is indeed a valid question here how fast our hand basket is really moving. In a recent article on RealClimate, there is a good discussion on if we should simply give up the fight because it is already meaningless. "Irrevesible" means that in a time span relevant to humans, we might not get everything back to normal (see the explanation of the carbon cycle with ocean's serving as buffers). "Unstoppable" means that no matter what we do, it is going to run it's cause.
The short answer is "No, we have to do something even more urgently than ever". Read for yourself.
Of course, in an older 2002 TED talk on science and philosophy, Kary Mullins refutes the scientific reality of climate change and, as expected, causes great discussion in the comments section of the talk. I wonder if he still believes his words from 7 years ago. To me just because we possibly do not have the right scientific model yet to accurately measure climate change does not mean the visible results are not real.