The latest IPCC report makes it clear no new fossil fuel projects can be opened. That includes us, Australia

There is a simple line in the latest report by the Intergovernmental Panel on Climate Change that quickly cuts through the Australian debate over the future of coal and gas.

It is based on physics and maths, and has been agreed by representatives from most of the world’s governments, who spent the past week in Switzerland thrashing out the wording of a synthesis document that brings together everything established on the subject over the past eight years.

It is this: greenhouse gas emissions from existing fossil fuel infrastructure is more than enough to push the world beyond 1.5C of global heating compared with pre-industrial times. Obviously enough, it tells us that no more fossil fuel sources can be opened if the world is serious about living up to its commitments and avoiding a significantly worsening climate crisis.

This is not a fringe position. It is a mainstream, globally agreed fact that is supported by nearly 200 countries, including Australia. But it is clearly at odds with the claims by the climate change minister, Chris Bowen, among others, that it would be “irresponsible to start placing bans on traditional energy supply like coal and gas”.

The politics is fraught as hell, but we need to acknowledge that the 1.5C goal matters – and that what Australia does matters. On a recent count, it was the third biggest fossil fuel exporter and the 14th biggest national emitter.

The 1.5C goal was agreed in the landmark 2015 Paris agreement and has been reinforced by global leaders several times since. The latest IPCC report stresses what missing it would mean.

At 1.1C of heating, the world is already experiencing more emissions-linked climate damage – worsening heatwaves, bushfires, storms and droughts – than was expected. Hitting 1.5C will escalate those extreme events. More people will die or have their lives wrecked by disasters, and species and natural systems that have existed for millennia will be lost.

From there it gets worse. Every fraction of a degree matters. As the director of Potsdam Institute for Climate Impact Research, Prof Johan Rockström, said this week with admirable understatement: “There is a growing recognition that 2C is dangerous.”

Bowen made the case as well as anyone has in an interview with Guardian Australia at the Cop27 climate talks in Egypt last year, when he argued: “If we’re not trying to keep to 1.5C then what are we here for?”

If Australian politics were not still shellshocked by the climate wars, that might be the question dominating parliamentary debate this week. Instead, negotiations continue in the background between Labor and the Greens over the safeguard mechanism, which is meant to cut industrial emissions, and what to do about new coal and gas proposals. Government forecasts suggest several major new fossil fuel mines will open in the years ahead, some of them “carbon bombs” likely to add substantial amounts to global emissions.

In the next few days it should become clearer whether the Labor and Greens can find middle ground that each can claim as a win: the government by saying it has not breached its election commitments and got its climate policy through, and the Greens by saying it has extracted concessions that will make it harder to develop fossil fuels and ensure emissions don’t increase.

The IPCC report shows that if we are serious we should turn the debate on its head. Given we can’t switch off fossil fuels overnight (and nobody is arguing we can) but must limit their use ASAP, the question should be: how much of them do we need to get where we want to be as cleanly and rapidly as possible?

On coal, a research brief by the Parliamentary Library, commissioned by the Greens, suggests existing mines could be enough to meet local demand until the country’s failing old coal plants are shut and replaced. If so, great.

On gas, the government – and others – need to stop conflating local demand with the desire for multinational companies to reap profits until well after 2050 by opening vast new fields for export. As the independent senator David Pocock said on Tuesday, the much-hyped shortfall forecast for local gas supply is a political construction: about three-quarters of what we extract is exported. That can be redrawn if there is political will.

We will need gas for longer than coal, but the amount used in manufacturing and as a back-up on the east coast electricity grid is a tiny fraction of what we already extract. Homes and businesses will need to be electrified. How about we be methodical, work out an estimate of how much gas we need and go backwards from there?

On exports, we need a more sophisticated conversation that avoids falling quickly into bad faith arguments about what is happening in China (which isn’t as clear as you might think). This should acknowledge where Australian fossil fuels are genuinely needed and on what scale, and where – after an aggressive fossil fuels sales pitch in Asia under the former Coalition government – we are locking in dirty emissions sources ahead of available clean options.

Which brings us to arguably the most important point from the IPCC synthesis report: there are clean options available. In the words of ANU professors and IPCC authors Frank Jotzo and Mark Howden, we are “up the proverbial creek – but we still have a paddle”. If available tech was quickly embraced we could at least halve global emissions by 2030 at a manageable cost.

There is hope for a faster change. Let’s act like it.