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THE annual ritual of working out where the previous 12 months ranks on the global “hottest-year-on-record” chart is well under way. It was another scorcher, according to a by the World Meteorological Organization – probably in fifth or sixth, in which case the past eight years will be the warmest eight on record.

Quelle surprise. As long as we keep on dumping greenhouse gases into the atmosphere, the climate will continue to heat up.

This is obviously alarming news, but, in truth, things aren’t as bad as they appear. Don’t worry, I haven’t fallen down a climate denial rabbit hole. We are still in trouble and need to act quickly. But the fact of the matter is that we are making decent progress. Ten years ago there was a genuine fear that we were heading for catastrophic warming of between 4°C and 5°C by 2100. Today, those worst-case scenarios are no longer plausible.

The story goes back to 2014, when the Intergovernmental Panel on Climate Change (IPCC) published 1184 future greenhouse . To make this baggy monster tractable, the scientists boiled them down to four: one very high scenario, one very low and two in between. The very high one assumed that there would be no climate action whatsoever and that use of fossil fuels would continue on an upward trajectory until 2100. It became known as the business as usual scenario, or BAU.

BAU quickly garnered more scientific and media attention than the other scenarios, in part because it extrapolated the situation at the time, but also because it made for sensational scientific papers and apocalyptic newspaper headlines. A BAU world would have been a “truly catastrophic hellscape of a planet”, says climate scientist Zeke Hausfather of NGO in California.

In the years since, however, the world has changed dramatically. Progress on renewable energy technology and implementation of climate policies have bent the emissions curve downwards towards warming of around 3°C by the end of the century. Still dangerous, but not hellish. And further progress isn’t just possible, but promised. show that, if countries achieve the net-zero pledges that they have already put on the table, warming will stay under 2°C.

As a result, the BAU scenario is no longer even remotely plausible, says , an environmental scientist at the University of Colorado, Boulder. Nor is the next-worse of the four. “It looks like the apocalyptic scenarios, as of today, are off the table,” he says.

If anything, says Hausfather, BAU was implausible in the first place. It wasn’t just a conservative extrapolation of current trends, but a turbocharged one that assumed, for example, that the use of coal would increase fivefold by 2100, with no climate mitigation action whatsoever.

And yet, the now-obsolete BAU scenario continues to dominate scientific discussions of our climate future. According to a by Pielke, the two most by the IPCC actually increased their emphasis on that worst-case scenario.

This bias is also reflected in scientific journals. An analysis by Pielke’s colleague found that in the aquatic conservation literature, over 90 per cent of papers published between 2015 and 2022 use the BAU scenario – and about a third use it exclusively. It leaks out into the news media too. “The picture that we paint in terms of science, assessment, journalism and policy is dominated by the most extreme scenario,” says Pielke.

This puts climate scientists on the horns of a dilemma. Do they admit BAU was never really that plausible and risk deniers saying “we told you so” and spreading further muck about climate modelling? Or do they keep pushing BAU and risk it becoming obvious they are hawking a straw man, opening the door to… deniers saying “we told you so”?

Honesty is surely the best policy. Deniers are going to deny anyway. Climate scientists arguably have a duty to tell it like it is, and let other people worry about the reaction. In any case, says Burgess – who studies political polarisation around climate issues – deniers are losing, thanks to renewable energy being so cheap and popular.

Perhaps a more pressing danger is that the abandonment of apocalyptic scenarios will send a message that we are out of the woods. We aren’t. Aside from the fact that 2°C of warming is dangerous, there are still big unknowns about how the climate system as a whole responds to emissions. The IPCC reckons that even on our current trajectory, we could push warming well over 3°C. If you want a hot tip for 2023, put money on it being in the top nine warmest years on record.

Graham Lawton is a staff writer at 91av and author of Mustn’t Grumble: The surprising science of everyday ailments. You can follow him @grahamlawton