Climate debate not so cool | OPINION

Climate debate not so cool | OPINION

OF CONCERN: While climate change and global warming are hot topics today, global cooling was worrying students back in the 1960s.

OF CONCERN: While climate change and global warming are hot topics today, global cooling was worrying students back in the 1960s.


In the 1960s, students were worried about global cooling. Oh how things change.



“LISTEN to the kids – we must act on climate.”

More of this later. Bear with me whilst I get it off my chest.

Climate change has morphed into global warming, and the big culprit is seen to be rising carbon dioxide levels, brought about by human activities.

These include engine exhausts and the spotlight is always on coal-fired power stations.

The coal is burned to produce steam to power the electricity generators and discharge carbon dioxide, which is always described as pollution.

(There are, of course, generators powered by renewables such as wind, sunshine and water – indeed, “the Hydro” was generating all electricity in Tasmania when I came here in 1978.)


It is rarely mentioned that this pollution is essential for photosynthesis, without which no plant food would be produced.

It may seem to you to be stating the obvious but I am wondering increasingly if such basic facts are slowly dropping off the radar in the school curricula.

“The present (2013) level of carbon dioxide in the atmosphere is 392 ppm (0.04 per cent)." 

"During the Carboniferous Period (300 million years ago), atmospheric carbon dioxide was 2000 to 3000 ppm (0.2 to 0.3pc) and the earth enjoyed warm temperatures, a humid atmosphere and the development of massive forests … (huge amounts) of carbon dioxide were captured by forest plants which subsequently formed extensive coal deposits.”

So, when they are burnt, it simply puts the carbon dioxide back whence it came.

“The current level of carbon dioxide is near the lowest on record over the last 500 million years." 

"It is deficient for optimal growth of many crops and vegetables and constrains food production."

"For this reason, market gardeners for the past 100 years have been adding carbon dioxide to glasshouses to achieve levels near 1000 ppm (0.1pc)… the optimum level for rice is between 0.15 and 0.2pc.

"Glasshouse-grown vegetables show yield increases ranging from 10 to 70pc with increasing carbon dioxide levels… (it) is the most common factor preventing photosynthesis from proceeding more efficiently.”

These positives are rarely mentioned in the debate (for want of a better word) about the reasons for global warming.

Ditto the actual contribution of mankind’s activities, the “anthropocentric” slant.

“Australia currently causes only 1.3pc of world-wide fossil fuel emissions… with a 5pc reduction in emissions which total only 1.3pc of the world total it is clear Australia would achieve no significant reduction in atmospheric carbon dioxide levels, despite its heavy economic cost.”

Getting back to where we came in on this column, my exasperation was triggered by an article in the local paper under that heading.

It begins: “Australian school children will skip school this Friday as part of a global movement of young people taking to the streets to demand action on climate change." 

"As a doctor and a father, I’ll be there supporting them.

"The kids are right – 25 years of climate inaction has brought us to the brink of a climate abyss. Our delayed response to climate change jeopardises human life and livelihoods.”

And so it goes on (in my defence, he’s a medical doctor, I’ve got a PhD).

It’s difficult to take it seriously when you read this:

“ …. presents humankind with the most important social, political and adaptive challenge we have had to deal with for 110,000 years." 

"Your stake in the decisions we make concerning it is of ultimate importance: the survival of ourselves, our children, our species.”

It’s difficult because the "…" is Global Cooling, as perceived by Lowell Ponte in his book “The Cooling” in 1975.

That was what was worrying us as biology undergraduates in the 60s.

I promise to be less intense next month.

The quotes are from “A review of the scientific evidence underlying the imposition of a carbon tax or ETS in Australia” by John Chambers et al in Energy and Environment, Volume 24, No 6, 2013.

  • Dr Mike Walker is a farmer and long-time contributor to Good Fruit & Vegetables. Feedback:

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