The quality of temperature data is often brought into question by Joanne Nova. Earlier this year Nova jumped on the “BLOCKBUSTER” bandwagon after a fellow climate “skeptic” Watts believe he’d found evidence that errors in the thermometer record supposedly exaggerated the warming by a factor of two.
As it turned out Watts’ unpublished paper had a number of problems …
Watts made the assumption that homogenisation of raw data is performed for spurious reasons rather than to correct for a physical change, whilst they listed some adjustments as things they would have to consider in future.
Watts’ paper was discussed and rebutted eloquently at Skeptical Science citing change of equipment, location, time of observation bias, an amplification error, comparing 20% raw data to 100% homogenised data and a failure to observe the impact globally. I can’t possibly add anything more to that detailed examination, however I would like to highlight (steal?) an example of why homogenisation is necessary when a station is relocated.
Also, if you were to ignore all homogenisation and simply use the raw data, the results do not differ by very much.
None-the-less Nova still announces in her posts that poorly cited weather stations are to blame for the increase in globally temperatures, but when pushed for hard evidence Nova fails to deliver. All part of her Merchant of Doubt role.