Claim: Infrared Thermometers Relied Upon To "Prove" Greenhouse Gas Warming... Actually Are Specifically Calibrated To Not Measure Greenhouse Gas Warming

 I've got your thermometer hangin'

From Ace of Spades:

They are calibrated to essentially ignore background radiation due to CO2 and H2O re-emitting heat. This is apparently what permits them to scan long distances-- they need to be set to avoid that sort of thing in order to take the temperature of a large mass of air.

But Global Warming scientists have long claimed the additional heat detected by IR thermometers must be evidence of greenhouse gas warming.

Not so, says the largest maker of such thermometers. The technology specifically excludes the measurements AGWers claim are being made.

Climate scientists had long believed infrared thermometers measured thermal radiation from the atmosphere and assumed it was ‘proof’ of the greenhouse gas effect (GHE). 

Their assumption was that infrared thermometers (IRT’s) were measuring ‘back radiated’ heat from greenhouse gases (including water vapor and carbon dioxide). But damning new evidence proves IRT’s do no such thing. 

Now a world-leading manufacturer of these high-tech instruments, Mikron Instrument Company Inc., has confirmed that IRT’s are deliberately set to AVOID registering any feedback from greenhouse gases. Thus climate scientists were measuring everything but the energy emitted by carbon dioxide and water vapor.

One of the researchers involved, Alan Siddons, has analyzed the GHE for over six years. He has long condemned the practice of using IRT’s as a means of substantiating the increasingly discredited hypothesis.