doogly wrote:heritage.org? you comin in here with bad jokes?
On the contrary, the way Randall presented this strip, that's exactly the kind of source we should be looking at. He said "When people say 'the climate has changed before', this is what they're talking about." No, this
is what they're talking about.
Anyway, dismissing based on source instead of actually pointing out the problems is crummy science. nash1429 is much more on point:
nash1429 wrote:It even says, right on your plot, that the data is limited to a random latitude band in the Northern Hemisphere. Can you show us one of the global mean temperature instead?
I agree, that would be a more useful thing to see. At the same time, Randall's timescale is carefully chosen too. It seems to be a widespread problem. Check out this preliminary poke at Google Images
. You'll notice two competing kinds of graph, and those trying to show recent warming always use short timescales like this comic does (usually much shorter), while those trying to show constant variation like to exaggerate the y-axis.
The basic problem with the data we have is probably unsolvable. There's no way to get day-to-day temperature readings from millennia ago -- we can only get large averages that smooth out variation. When the question at hand is all about variation ("Should we panic over these recent trends or do they happen a lot?"), that's not much help.