Warming: It depends how you measure it...

Recent posts here at Not PC have referred to the reservations reasonable scientists have about the gathering of the surface temperature record. ( Vincent Gray summarises the problems here [pdf].)

For a wee visual hint at what some of those reservations are, Anthony Watts has been exploring Californian weather stations to examine the physical locations in which temperature is recorded. Here's one at Maryville, California, considered a "high quality" station in the station list used to calculate global "warming":

And here's the temperature chart for this location over the course of a century or so:


For comparison, here's the chart for a temperature station nearby that's out in the middle of a field:Can anyone say "Urban Heat Island effect?" When you consider that the "corrections" made by the UN/IPCC warmists to the surface temperature record to account for such abominations is anything but peer reviewed, and relies largely on the say-so of one man, Phil Jones, who insists that a correction of 0.05 degrees per century is sufficient, but then refuses to let his working be checked by reliable statisticians [story here] ... well, I'll let Anthony and Steve McIntyre and their commenters take up the explanation from there.

But just remember pictures like these when you're told by Simon and Wendy that Month X was the warmest in Y million years. And if you're passing a temperature collection location, take a photograph and send them to Roger Pielke Sr. and to Anthony at SurfaceStations.Org [perhaps see if it's already been recorded here first]. How could it hurt?

• Anthony Watts: How Not to Measure Temperature
• Steve McIntyre: Quality Control Jones & Hansen Style