Perhaps fill it with anti-environmentalist nutters who think that nothing we do has any impact on the world. Probably the same blindly short termist pro-business types who were fighting the good fight on behalf of the tobacco companies before they lost that one, or fighting against pollution controls on factories, before we found all the dead / mutated fish etc.
Joe
Nothing to do with if I think humans are causing climate change or not (I happen to think they are), but it really annoys me when people do this. The estimate that they had was out by a massive amount, and it was revised when the Icelandic volcanoligist said the output was "between 150,000 and 300,000". So, what figure do you use for your graph? Surely 225000 would be the best? No, 150,000 so air travel looks much worse in comparison.
Give people the correct and unbiased information, and then let them make a decision based on it. If people are going to be convinced of the existance of climate change, this sort of thing and the glacier debacle are what stand in the way to some extent.