JoNova

A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


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The Skeptics Handbook

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The Skeptics Handbook II

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The Conversation — cleansing skeptical thoughts — Read the banned comments here

The Fake Conversation where Bill’s informative, polite comments are removed, but the replies are left there.

Last week Bill Johnston posted a detailed, comprehensive analysis of Sydney Observatory thermometer record here that shows that most of the warming recorded there is due to buildings and freeways. But photo’s and graphs are “denier” stuff, and The Conversation is so afraid some its readers might see those historic photos they ban links to Bill’s work and joannenova.com.au. Apparently when the Bureau of Meteorology discusses “Australia’s hottest decade” it is off topic to discuss the condition of their thermometers.

Bill Johnston was happy to defend his work in comments at The Conversation, but Blair Trewin, who wrote the post itself, was entirely absent. Cory Zanoni had to close the dangerous thread. He removed scores of comments, but left replies to Bill Johnston intact. Some “conversation”.

At least 46 of Bill Johnston’s comments were deleted from Australia’s climate in 2016 – a year of two halves as El Niño unwound   and 19 deleted from Australian climate politics in 2017: a guide for the perplexed. As Bill says: They obviously want to stay perplexed; uninformed; scary-cats, without a paddle for their leaky canoe.

Some skeptics [...]

Blockbuster: Are hot days in Australia mostly due to low rainfall, and electronic thermometers — not CO2?

Blame dry weather and electronic sensors for a lot of Australia’s warming trend…

In this provocative report, retired research scientist Bill Johnston analyzes Australian weather records in a fairly sophisticated and very detailed way, and finds they are “wholly unsuitable” for calculating long term trends. He uses a multi-pronged approach looking at temperatures, historical documents, statistical step changes, and in a novel process studies the way temperature varies with rainfall as well.

His two major findings are that local rainfall (or lack of) has a major impact on temperatures in a town, and that the introduction of the electronic sensors in the mid 1990s caused an abrupt step increase in maximum temperatures across Australia. There will be a lot more to say about these findings in coming months — the questions they raise are very pointed. Reading, between the lines, if Johnston is right, a lot of the advertised record heat across Australia has more to do with equipment changes, homogenisation, and rainfall patterns than a long term trend.

Bill Johnston: On Data Quality [PDF]

“Trends are not steps; and temperature changes due to station changes, instruments and processing is not climate change”, he [...]