How bizarre- the Bureau of Meteorology has adjusted Australia’s temperature records to exaggerate the warming trend of the last century. The next time the media tell us it’s a record high temperature or an angry summer you might need to ask, “What does that even mean?”
From Jo Nova:
Australian summer maximums “warmed” by 200%
Which causes more summer heatwaves: carbon dioxide or Bureau of Meteorology (BOM) adjustments?
Ken Stewart has analyzed the adjustments used to create the all-new ACORN wonder dataset and compared them with another BOM dataset called AWAP, and finds, extraordinarily, that the trend in average summer maximums has been tripled by adjustments that the BOM imply are neutral.
Since summer maxima are the ones used to generate the most headlines in Australia, I ask again if the Bureau of Meteorology is a scientific agency or a PR group? Increasing the trend in summer maxima would produce more headlines of hottest ever month, season, heatwave, and weekend.
In this graph Stewart splits the data into months, and compares the trends in maxima in the AWAP and ACORN datasets, across the entire nation. We see that most of the adjustments happen to data from the hottest months of the year, October to March. Even though the measured maxima in February and March are possibly cooler now than they were in the early 1900s, they have been adjusted to show warming trends.
When was the last time you heard the BOM tell you that their “hottest ever” February record depended on adjusting down the past hotter records?
Full story: Australian summer maximums “warmed” by 200% « JoNova.