The 2 million Australians who organizers said joined in March's Earth Hour were disappointed that turning off the lights for 60 minutes only saved the equivalent of one person's carbon output for one year. ( dpa )
They shouldn't have been so surprised: among big countries, only the United States pumps out more carbon per capita.
A better way of trying to save the planet, argues University of Western Australia researcher Barry Walters, would be to switch the focus from limiting consumption to practising contraception.
The key to curbing the greenhouse gases that cause climate change, Walters writes in the Medical Journal of Australia, is cutting the birth rate. He wants a carbon tax on births.
Heather D'Agnes, head of population, health and environmental programmes at the United States Agency for International Development (USAID), said in Sydney recently that politicians were loathe to accept that population control was a cheap and effective way of addressing climate change.
She advocated initiatives to keep the global population to the low end of growth ranges - between 7 billion and 11 billion - by 2050.
Rather than advocating birth control, Canberra is actually paying women to have babies. From July, the mother of any baby will receive a grant of 5,000 Australian dollars (4,500 US dollars).
The baby bonus has sent the birthrate soaring. There were 265,922 births last year, the highest since 1971. The number of live births per female has risen to 1.81 from 1.77 in 2004.
Adelaide-based social worker Sue Vardon said some women were giving their babies back to the state to be looked after once they had picked up the cheques for having them.
"Are there lots of people now who are having babies because there's a 5,000-dollar payment out there?" Vardon asked. "We know that some young women are stood over for the 5,000 dollars with their druggie friends and they're having babies every year because of it."
The new government under Prime Minister Kevin Rudd has pledged to stick with the baby bonus. Some academics are brave enough to question the wisdom of that.
Jack Pezzey, an environmentalist at the Australian National University, said half of the increase in energy consumption could be put down to population growth and that by 2020 "it will contribute about 20 per cent of the growth in emissions and that will make it that much harder to meet any ambitious reduction target like getting our emissions down to 25 to 40 per cent below our 1990 levels."
There an equity issues to consider as well.
The carbon footprint of a single Australian is equivalent to the carbon footprint of several people from the developing world. On one estimate, the emissions linked to one birth in Australia is equivalent to eight births in neighbouring Indonesia. By that measure, the 265,922 births in Australia last year would equal, in carbon footprint terms, the birth of 2.1 million Indonesians.
In climate change terms, slowing population growth in Australia would have a bigger impact that slowing population growth in Indonesia.