Planet’s population is the biggest cause for global concern

Most people consider COVID-19, global warming, species extinctions and other catastrophes as individual events, but I consider them as symptoms of one overarching problem: global population.

It took two million years of human activity for the world’s population to reach one billion, but only another 200 years to reach seven billion. As of March the total was 7.8 billion and the UN estimates by 2050 the total will be in the range of 8.3 to 10.9 billion.

As interesting as these figures are, they mean little unless a meaningful comparison can be made with the population capacity of the planet. Paul Ehrlich, Professor of Population Studies at Stanford University, reckons this number to be between 1.5 and 2 billion, but I suspect this is a bit conservative. If we doubled this estimate, that would correspond to the period of 1960 to 1975. A lot of my baby-boomer friends and I often claim we lived in the best of all times and this estimate just confirms that.

All natural systems have the capacity to correct themselves; the question is, can we manage that correction or will the planet do it for us whether we’re ready or not?

Geoff Mathews, Glenelg North, SA

The real gas problem

Further to Douglas Mackenzie’s letter (17/9), might I opine that the more potent greenhouse gases causing global warming are from the suite of HFC (hydrofluorocarbon) refrigerant gases being released daily (lighter than air) into the upper atmospheres from the multi-billions of the world’s cooling systems (airconditioning). Specific HFCs have 1500-4500 times more potency per kilogram than the plant food carbon dioxide.

Whereas CO2 can be sequestered by nature, nature is unable to neutralise the millions of tonnes of these synthetic HFC chemicals that are released annually and that continue to linger in the stratosphere for many decades, perpetuating global warming and disturbances. Manmade HFC chemicals are the “elephant in the environmental room”, not nature’s plant food CO2 released from fossil fuels and mammals.

David Spratt, Mosman, NSW

Churchillian flourish

R.C. Warn offers an interesting reflection on the Chinese historical outlook (Letters, 17/9), but he misconstrues Winston Churchill, who said the following in a speech broadcast by the BBC in January 1940, reflecting not on appeasement but neutrality at that point in the war (when the US was still on the sidelines): “Each one hopes that if he feeds the crocodile enough, the crocodile will eat him last. All of them hope that the storm will pass before their turn comes to be devoured. But I fear greatly that the storm will not pass. It will rage and it will roar ever more loudly, ever more widely.”

The word “appeaser” crops up in later, postwar variants of that text.

Paul Ellis, Toronto, NSW

The bear facts

Reason and truth in matters of conservation are rare so it’s time we sought it out more vigorously. The koala issue is a typical example. We are told they are endangered because of a new residential development of a few hectares on the edge of one of our cities. If you drive the 3000km from Cairns to Melbourne you are struck by the unbroken chain of eucalyptus forest along the mountainous spine. This is all koala habitat and extends westwards into the tablelands. And we fret over a few hectares.

Conservationists claim there may be only 40,000 koalas left in the wild but claim also that 30,000 died in the fires of last summer. At the very worst approximation maybe a few per cent of the total koala habitat was burned last summer, but the shrill voices want us to believe that 75 per cent of our koalas perished.

Like many conservation causes this one suffers a credibility crisis. More truth, less hysteria please.

Keith Mouatt, Robina, Qld