So an early season snowstorm in Chicago is now evidence of global warming?????
Well, yes, it is. Al Gore, winner of the Nobel Prize in climatology explained it. As the globe warms up, it cools down, or something.
Deniers go on and on about the Medieval Warm Period this, and the Little Ice Age that, but Professor Michael Mann has written a computer program which proves without a shadow of a doubt that these two alleged events never happened. His program demonstrates that the climate was absolutely stable until about 1970, when evil Republicans invented the SUV.
His computer model is so robust that whatever data is fed into it, the same result emerges. What more proof could the Deniers want?