Claims that climate scientists have abandoned their most dire scenario have been widely misunderstood. While the highest emissions pathway is now considered unlikely, evidence suggests the climate system may still be tracking toward dangerously high levels of warming.

Occasionally, climate science is big news. On 26 May, the New York Times headlined: “Why scientists retired the dire climate scenario used for over a decade”. A good story!

The Australian, true to form, went with “Climate doomsday scenarios just got a major rewrite”, and in Jeff Bezos’s Washington Post it was  “The climate apocalypse? Don’t count on it”. There were a host of similar headlines.

Climate deniers and Donald Trump used an old playbook to claim scientific fraud (surprise!), but were called out, with ‘Trump twisted a climate debate beyond recognition’ and ‘Factcheck: Trump’s false claims about the IPCC and ‘RCP8.5’ climate scenario’.

So what’s the real story? Did scientists get it wrong, and is warming now likely to be less severe than previously thought?

As in engineering and business and government, scenarios are used by climate scientists to think about plausible alternative futures and their risks. The commonly-used climate scenarios are based on different possible trajectories for human greenhouse gas emissions and the social path humanity takes, and the consequences. And remember, scenarios in the end are simply a product of the minds that imagined them.

Fifteen years ago, four scenarios called representative concentration pathways (RCPs) were developed for the fifth IPCC assessment report in 2014, with RCP2.6 the lowest and RCP8.5 the highest. The numbers are radiative forcing (RF) values in........

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