This is a Letter to the Editor of The Australian I sent recently, but not published.
Dr Jennifer Marohasy (Ideology adds heat to the debate on climate change, 29/9) claims that sites prone to Urban Heat Island effect, such as Melbourne, have been used to adjust the temperature records at sites such as Cape Otway.
This is indeed absurd, but true. Of the 104 sites used for climate analysis, 22 have been adjusted at least in part by comparison with sites whose artificially raised temperatures make them unsuitable for use in that same climate analysis.
The Bureau of Meteorology lists eight sites which are not used in climate analysis because their records exhibit Urban Heat Island effects: Townsville, Rockhampton, Sydney, Richmond (NSW), Melbourne, Laverton RAAF, Adelaide, and Hobart.
According to the Bureau’s “ACORN-SAT Station adjustment summary”, seven of these sites are still used as comparison sites when adjusting raw temperatures at other locations. Adelaide is used at Snowtown and Port Lincoln; Townsville at Cairns, Mackay and Charters Towers; Rockhampton at Townsville, Mackay, Bundaberg and Gayndah; Sydney at Williamtown, Bathurst, Richmond, Nowra, and Moruya Heads; Laverton at Orbost, Sale, Wilson’s Promontory, Melbourne and Cape Otway; Melbourne at Orbost, Sale, Wilson’s Promontory, Laverton, Kerang, and Cape Otway; and Hobart at Launceston, Eddystone Point, Cape Bruny, Grove, and Butlers Gorge.
Richmond (NSW) is apparently the only site not used in the adjustment process.
Greg Hunt’s faith in the credibility of the Bureau of Meteorology is touching, but just as absurd.