Ross McKitrick has an op-ed piece in Canada's National Post on a serious problem with the Intergovernmental Panel on Climate Change's latest report.

In the first draft of the IPCC report, they simply claimed that, while city data are distorted by urban warming, this does not affect the global averages. They cited two familiar studies to support their position and ignored the new counter-evidence. I submitted lengthy comments criticizing this section. In the second draft there was still no discussion, so again I put in lengthy comments. This time the IPCC authors wrote a response. They conceded the evidence of contamination, but in a stunning admission, said: "The locations of socioeconomic development happen to have coincided with maximum warming, not for the reason given by McKitrick and Mihaels [sic] (2004), but because of the strengthening of the Arctic Oscillation and the greater sensitivity of land than ocean to greenhouse forcing, owing to the smaller thermal capacity of land." Note the irony: Confronted with published evidence of an anthropogenic (but non-greenhouse) explanation for warming, they dismissed it with an unproven conjecture of natural causes. Who's the "denialist" now?

Furthermore, the claim is preposterous. The comparison of land and ocean is irrelevant since we were only talking about land areas. The Arctic Oscillation is a wind-circulation pattern that affects long-term weather trends in the Arctic. It certainly plays a role in explaining Arctic warming over the past few decades. But for IPCC lead authors to invoke it to explain a worldwide correlation between industrialization and warming patterns is nonsense.

Manhattan today is hotter than it was when it was purchased from the Indians for $16 worth of trinkets. That's not proof that the Earth as a whole has warmed. There's millions of people there now, heat-trapping asphalt and all sorts of heat-generating sources.

But the global warming alarmists will hold tight to their narrative, even as study after study raises questions about their methodology, science and computer models.