Sustainable Population Party founder William Bourke isn’t exactly your run-of-the-mill border-control enthusiast.

Bourke is not so much worried that foreigners will refuse to embrace Australian values as he is concerned they’ll do so all too enthusiastically – with dire consequences for the local environment and global climate.

Given the carbon footprint of the typical Australian is more than three times larger than the global average, Bourke argues that introducing ever more people to the antipodean way of life is about the least helpful thing we can do in the global fight against climate change.

“If [immigrants] are coming, as is likely, from a country with lower per capita emissions, when they move here their emissions go up,” he said.

“Population, like climate change, is a global problem that needs to be addressed at a local level with each country taking on the responsibility to reduce.”

His concern about the environmental impact of Australia’s projected population boom is particularly relevant against the backdrop of the COP21 summit in Paris, where the Turnbull government doggedly defended itself against criticism that Australian emission reduction targets are inadequate by framing them in the context of our growing population.

Bourke rejects the political orthodoxy of environmental issues being a concern of the left and immigration control being a focus of the right, claiming instead that the two issues go hand in hand.

Although Greens voters are by far the most welcoming of asylum seekers, they are by far the most uncertain about the prospect of the Australian population increasing beyond 35 million.

The idea that immigration should slow to help Australia tackle its carbon emissions has also been spruiked by the likes of progressive think tank The Australia Institute and the Australian Conservation Foundation, and the Sustainable Population Party enjoys support from figures as disparate as Climate Council head Professor Tim Flannery and climate sceptic Alan Jones, the latter of whom enthusiastically backed the party’s stance on immigration on his 2GB radio program in the lead-up to the North Sydney byelection last weekend.

Bourke stood as a candidate in the election and secured 3 per cent of the vote, which the party trumpeted as their best ever result.

The result was still behind the byelection’s other ecologically branded political force, the Greens, criticised by Bourke as a party that once led the way on the topic of stabilising the population before abandoning all talk of the issue once it became associated with divisive figures such as Pauline Hanson.

“I think [the Greens] fear being aligned with anti-immigration parties,” he said, “so they dropped the ball on the issue of population, and the environment has suffered.”

The Greens claim they have remained consistent on this issue, and oppose at least in principle the aim of a “Big Australia”, threatening an inquiry into the idea when former prime minister Kevin Rudd coined the term in 2009.

The Greens’ co-deputy leader, Senator Larissa Waters, said in terms of climate action the primary focus should lie in making Australia’s cities, farms and industries more sustainable, goals that align with the Sustainable Population Party’s policies.

“Human impacts on the environment and the climate are not determined by population numbers alone, but the way we live and our energy choices,” she said.

Greens supporters are somewhat conflicted over the issue. A late October Roy Morgan poll on the idea of a Big Australia indicated that although Greens voters are by far the most welcoming of asylum seekers, they are no more enthusiastic than other voting blocs in regard to skilled migration – which accounts for the bulk of Australia’s population growth – and are by far the most uncertain about the prospect of the Australian population increasing beyond 35 million.

With the population poised tosurge past 24 million, it is clear that a Big Australia inevitably looms if the course does not change. According to the Australian Bureau of Statistics, the country’s population is projected to increase to between 36.8 million and 48.3 million by 2061, and reach between 42.4 million and 70.1 million in 2101.

Projections are just projections, of course, and these are already a little out of date – based on Australia’s circumstances in 2012, when economic conditions were better and the country was attracting a higher net intake of migrants. The 2014-15 period yielded net overseas migration of just 184,100, well below the higher-end ABS modelling, which assumed a net intake of 280,000 a year. Nevertheless, with more immigration than emigration and a slightly-above-replacement-level birthrate, Australia’s population continues to expand.

It is not just the emissions of these extra millions that are of concern, but also the fact they will need to be accommodated in an environment that, thanks to climate change, looks set to become increasingly hostile. According to the Bureau of Meteorology and CSIRO 2014 “State of the Climate” report, rainfall averages could plummet across food-producing areas of south-eastern Australia by up to 70 per cent by 2070, with far more common periods of drought and days of extreme heat.

In October the Climate Council examined what this would mean for Australian food security, and found that water scarcity, heat stress and increased climatic variability in food-producing regions such as the Murray-Darling Basin would imperil Australia’s food supply at a time when there are more mouths to feed than ever, with domestic demand forecast to be as high as 90 per cent above 2000 levels by 2061.

But then, this continent is not the only place set to be besieged by climate change, and in a per capita sense Australia ranks near the top in more than just carbon emissions – it is also one of the wealthiest places on earth. Australia is among the best equipped to deal with the coming pain, and according to the United Nations it is people living in developing nations who are expected to suffer the most from global warming.

The Greens, who advocate an intake of 30,000 refugees annually, are pushing for a greater focus on people displaced by climate change, however some experts are pushing for greater synergy with Australia’s vastly larger skilled migration intake.

Professor Jane McAdam, director of the University of New South Wales Andrew & Renata Kaldor Centre for International Refugee Law and author of Climate Change, Forced Migration, and International Law, said those who think slowing immigration is an appropriate response to climate change need to look at the global context. “To say ‘Cut immigration to Australia’ is, I think, a narrow and blinkered view.”

McAdam pointed to the 26 million people displaced annually as a result of disasters consistent with climate change trends. She said in the Pacific region there are increasingly serious threats facing countries such as Kiribati and Tuvalu, where water supplies and other natural resources will soon be put under severe strain. Australia’s taking in of more people from such places would allow smaller populations to remain on the islands for longer, serving as a kind of adaptation strategy.

“The Kiribati president [Anote Tong] has spoken in regard to migration with dignity – the opportunity to move for labour or family reasons rather than waiting for a disaster,” she said.

In addition to a greater humanitarian response, McAdam recommends Australia look to what New Zealand has done in establishing special visas for Pacific Islanders that allow them to migrate permanently, provided they have secured a job offer before moving.

“Many people reject the term ‘climate change refugee’ quite strongly,” she said.

“They say, ‘We don’t want to have to rely on handouts, we want to bring skills to your country.’ ”

That is not to say those proposing slower population growth in order to protect the environment are suggesting Australia wash its hands of the rest of the world’s problems.

Both the Greens and Sustainable Population Australia advocate for significant boosts in foreign aid, geared around measures such as female empowerment, family planning services and reproductive health, to help control global population growth, which the UN estimates will see our planet carrying nine billion people by 2050.

If many of them end up with carbon emission levels the equivalent of Australian citizens today, the world would clearly be in deep trouble. But only allowing entry to Australia for a tiny fraction of the millions displaced by climate change because we fear they would adopt our carbon footprint? That would be a bit rich.