The whole AGW belief system is based upon positive water vapour feedback starting from the pre-industrial level of 280 ppm and not before
That means the warming is only from the CO2 by adding up the short bars in the chart. It is fairly certain in theory that the CO2 is causing that warming and even more likely that the CO2 rise is manmade. So that part is not a "hoax". I have to say "in theory" because there could be negative feedback. But Archibald is not presuming either positive or negative feedback, but simply the warming shown in the chart. It is not significant warming (adding up those bars) but nor is it a trivial 0.0028 like your pie chart. I would dump the pie chart since both the CO2 piece is too small and the manmade piece is way too small (likely due to not using net natural, only one way natural)
For a great discussion of the CO2 myth and AGW, go here:
http://www.skepticalscience.com/human-co2-smaller-than-natural-emissions.htm