Article by John O’Sullivan and Val Majkus
Global warmers in full retreat as Aussie experts admit growing doubts about their own methods as new study shows one third of temperatures not reliable.
The Australian Bureau of Meteorology (BOM) admits it was wrong about urban heating effects as a professional statistical analysis by Andrew Barnham exposes a BOM claim that “since 1960 the mean temperature in Australia has increased by about 0.7 °C”; the BOM assertion has no empirical scientific basis.
Barnham, who spent 8 years working in emerging South Asian economies building high volume transaction processing systems, applied a high-tech statistical technique very different from an earlier well-publicized probe by fellow Aussie, Ken Stewart on his blog, Ken’s Kingdom.
Stewart grabbed headlines in what became known as the Australiagate controversy after his findings were featured on popular science blog, Watts Up With That. Stewart exposed dubious BOM adjustments to temperature data that bore little or no resemblance to actual or raw past temperatures.
Like Stewart, Barnham paid particular attention to BOM’s methodology in addressing what is known as the Urban Heat Island Effect (UHI), a proven phenomenon whereby thermometers measuring temperatures in towns and cities become unduly influenced by extra ‘background’ heating from buildings, road surfaces, machinery, etc. It’s in the UHI adjustments that the greatest discrepancies appear to lie.
BOM Errors in the Urban Heat Island (UHI) Effect
A chastened BOM is now starting to questions its own UHI adjustments. A recent BOM media release referring to a paper presented at the Australia – New Zealand Climate Forum in Hobart (October 14, 2010) admits it formulated its calculations incorrectly.
BOM concedes that daytime temperatures in Aussie cities are warming more rapidly than those of the surrounding countryside and that this is due to the cities themselves. In effect, the admission undermines all prior claims that such warming is principally due to man-made emissions trumpeted in the similarly discredited “greenhouse gas theory.”
Skeptical researchers have long argued that little or no weighting has properly been ascribed to the UHI phenomenon; this apparent U-turn may signal the demise of the now discredited official adjusted Australian temperature record.
Bureau climate scientist, Belinda Campbell, admits "we’ve known for a while that city night time temperatures have been warmer because the heat’s retained after sunset just that much longer than the countryside, and that city daytime temperatures have been warming too. But what we didn’t know was whether city daytime temperatures were also warmer because of the urbanisation or whether it was due to the overall warming of the planet associated with the enhanced greenhouse effect. We can now confidently say that the reason our cities are warmer and warming faster than the surrounding countryside during the day is because of the urbanisation, the fact that all those offices, houses and factories absorb the heat and retain it a little bit longer."
See the full discussion on BOM’s belated discovery on the excellent WUWT blog.
‘Homogenization’ – that Euphemism for Data Fudge
In February 2010 John O’Sullivan published an article, ‘Australiagate: NASA Caught in Trick over Aussie Climate Data’ that drew attention to the fact that spuriously warmed Aussie climate data was being trumpeted by the Intergovernmental Panel on Climate Change (IPCC). With these latest findings Barnham says, “My results raise a number of issues with the quality of the data and supporting analysis provided by BOM.” Readers are encouraged to compare Barnham’s findings published on joannenova.com.au with those of Stewart.
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