Kevin Drum links to an NAS report on global warming, and includes a nice graph...you know, one of those that sums up graphically the whole point and demonstrates beyond a doubt that the sky is falling. Follow the link, have a look...I'll wait.

Okay, I guess you're just supposed to look at the rising lines on the end and go "Yeah, we're screwed." Funny that...first thing I tend to do when presented with graphs now, after a pretty fair amount of reading published scientific articles in peer-reviewed journals, is look at the axes and the scale. That's the main way to distort information graphically, if one were so inclined.

The X-axis is fairly straightforward, though they indicate with the gray background shading that estimates are less accurate the further back in time we go, and that estimates are very unreliable prior to 900 AD. Hmm, okay. So if such fluctuations were within the natural range over periods longer than 2000 years, this graph wouldn't reflect it. We know, for example, about ice ages and periods where the earth was much hotter than it is now. It would be nice to see estimates over much larger time scales...my guess is that our recent fluctations would be dwarfed by the larger flucations over larger timespans.

The other thing that put my radar up was the Y-axis. "Temparature anamoly (deg C)". What the hell does that mean? Anamoly means something deviating from the expected, and if you look at the actual axis values, 0 is in the middle. So according to their own data and estimates, temperatures for most of the past millenium have been anamolously cold.

I have little doubt that human activity has an effect on environmental conditions, but I have a pretty good nose for bullshit, especially bullshit presented in graphical form. And this one doesn't smell right.