During the middle 1970s, most climate scientists believed that another ice age was imminent, with fears reaching their highest point during the frigid Eastern United States winter of 1976/1977, and in several cool Arctic summers earlier that decade.
In the Northern Hemisphere, a general cooling was widely noticed between 1940 and 1975. For instance:
- there was not one subzero Central England Temperature (CET) month between March 1895 and December 1939, but
- five between 1940 and 1975
- and as many as seven between 1850 and 1895
However, in Australia, annual mean temperatures showed a somewhat different pattern, as can be seen from this graph of annual mean maximum temperature:
As you can see, and as I have noticed since 2000, Australia saw a major rise in mean annual temperatures in the late 1950s, notably from (fiscal year) 1955/1956 to (fiscal year) 1957/1958. There was no downward trend in Australian mean maximum temperature at any point between 1956 and 1975. Only one year (July 1966 to June 1967) between 1957/1958 and 1972/1973 is more than fractionally below the virgin mean.
Whilst these figures would have been valuable to those discussing climate trends during the 1970s, it surprised me that the Brisbane Courier-Mail, in February 1974, published a detailed analysis of January 1974’s super-monsoon that saw an all-Australia rainfall of over 230 millimetres – whereas Australia’s wettest month between 1890 and 1973 was around 128 millimetres!
The Brisbane Courier-Mail’s article, titled ‘Floods Part of Our New CLIMATE Pattern’ was also focused on the unusual equatorward displacement of summer rain belts in the Southern Hemisphere during the 1960s. Great Barrier Reef coral cores suggest that the decade from 1960/1961 to 1969/1970 may have been Queensland’s driest since at least 1631.
What ‘Floods Part of Our New CLIMATE Pattern’ and published on 19 February 1974, was highly prescient about is:
- the (continuing at an accelerating rate) southward shift of winter rain belts in the mid-latitudes of the Southern Hemisphere (central Chile, southern Australia, southwest Cape)
- that in these regions there already existed evidence of poleward movements in the late 1960s and early 1970s, though not nearly so much as since 2010 when climatic displacements poleward reach between 5˚ and 7˚ of latitude (550 to 770 kilometres) vis-à-vis preindustrial climates
- the poleward shift of summer rain belts in Australia, and also Northeastern Brazil and Southern Africa, during the 1970s, especially January 1974
- although January 1974’s record has not been approached subsequently, there have nonetheless been ten months since with higher all-Australian rainfalls than the wettest month between 1890 and 1973.
- these months and years could be called super-monsoon months, since all were due to more southerly monsoon troughs and depressions than anything known before 1974, and likely anything since minimally the fifteenth century
- the continuation of the observed trends in rainfall over the previous few years indefinitely
The only problem with ‘Floods Part of Our New CLIMATE Pattern’, of course, is that the article does not relate it to man-made greenhouse gas emissions, in which Australia is (since 1980 at least) of course by far the world’s worst offender. It is remarkable even with this severe limitation that such a popular article manages to explain climatic changes that were beginning in 1974 and are accelerating as I write this. The tragedy is that the public was never encouraged to grasp the changes – but then, encouraging the public to understand would be immensely threatening to Australia’s super-rich and super-powerful greenhouse emitters.
