This led to an interesting e-mail exchange between myself and one of my blogging friends, whom I won't name because (a) the e-mails weren't really intended for publication, and (b) he's a good guy who is passionate about doing what's right.  I got an e-mail from him challenging me on this point, saying the correlation between rising temperatures and mass release of CO2 was undeniable. I explained to him that AGW skepticism doesn't rest on the notion that global temperatures aren't rising, but that the AGW crowd has yet to show causation  between CO2 release and actual warming.  He replied that correlation was enough to prompt action, but that's neither scientific or wise.  Correlation only shows that two trends parallel each other; if one isn't the cause of the other, then "solutions" designed to change one trend won't impact the other anyway - and it will waste time, money, and perhaps lives while the perceived problem continues unabated.

As it turns out, the correlation isn't exactly equal, either.  A closer look at the data and a Daily Mail interview with one of Muller's team shows that the chart hides the fact that no warming has occurred in the last 11 years, as has been repeatedly pointed out