From the BBC:
Australia has experienced its hottest day on record with the national average temperature reaching a high of 40.9C (105.6F).
The Bureau of Meteorology (Bom) said "extensive" heat on Tuesday exceeded the previous record of 40.3C set on 7 January 2013. Taking the average of maximum temperatures across the country is the most accurate measure of a heatwave.
From Realclimatescience.com:
There are 25 locations in Australia with daily temperature data going back before 1890. This graph shows all 1,389,419 daily maximum temperature readings at those locations since 1876.
The actual waveform is a 120 year long cycle. The hottest year was 1902 and the second hottest was 2018. Australia was cold during the 1970s ice age scare, just like everywhere else.
At least one of them is grossly misrepresenting the actual situation.
Debate Magazine
