Climate change and population

Blake Briggs writes: Re. “The dirty little secret to tackling climate change” (yesterday). Cathy Alexander’s article was an oversimplification of the maths of the link between emissions and immigration. To argue that Australia would have lower emissions if we had a smaller population is true, but ignores that there would be no net change in global population. There would therefore likely be no net change in global emissions, and no net global environmental gain … but hey, at least Australia would have reached a few of our own targets and would have bragging rights.

A flaw in my argument is that many immigrants to Australia come from poorer countries with lower emission per capita. Hence, once having immigrated to Australia a person’s emissions may be higher that they would have been in their country of origin because they live a higher standard of living here. But I don’t think Alexander was arguing we should cut immigration to compel people to live in poverty overseas so that their emissions are lower, allowing us that remain in Australia to stay higher on a per capita basis.

The true issue is: how do we achieve higher standards of living with lower emissions, regardless of which country you live in? Australia should be using its economic growth, which is strongly linked to population growth, to help fund a shift to low-emission electricity generation. Immigration seems only to be a decoy from self-interested “close-the-door” lobby groups.

Alan Baird writes: Cathy Alexander’s article has been, is and will be, on the money for years. In addition, nearly all of the migrant intake comes from countries of low emissions intensity and we quickly convert them to a (comparative) sky-high intensity, a considerable achievement. Does this mean we should import humans from Dubai instead and send back the rest? Or perhaps Kelvin Thomson should be silenced for stating the bleeding obvious? And what about the growth, mate? We gotta do that forever!

Charles Berger writes:  Cathy Alexander acknowledges that her analysis of the link between population growth and greenhouse pollution is “rough and no substitute for rigorous modelling by teams of economists and demographers”. In fact, an interdisciplinary team of researchers from Flinders University and CSIRO were commissioned by the Department of Immigration and Citizenship to do exactly that a few years ago. Their final report, released in 2010, runs to over 300 pages. It defies easy summary, but it is certainly the most extensive and credible analysis of the physical implications of migration in Australia ever conducted.

On greenhouse pollution, the modelling supports Alexander’s analysis. A zero net migration policy would result in a 60% increase in greenhouse pollution from fuel combustion by 2050, whereas a net annual migration rate of 180,000 would result in a 170% increase. The study also found that higher rates of net overseas migration exacerbate a host of other environmental and quality of life pressures, including water use, urban sprawl, and traffic congestion.

An immediate move to zero net migration would necessitate cuts to the family and/or humanitarian migration stream, which some Australians would find unacceptable. However, a modest net migration level of around 50,000 is achievable through reductions in skilled migration and would lead to population stabilisation by mid-century.

It’s a pity this report has not attracted the media coverage or policy influence that it deserves. Having commissioned the work, it would be worth asking the department what steps they have taken in response to its findings.