Science is not supposed to mislead. It’s supposed to be precise. Rigorous. Circumspect.
But in recent years, something sneaky and unethical has occurred. Officials have begun talking about the worst-case climate scenario is if it were our likely future.
More than a decade ago, the Intergovernmental Panel on Climate Change developed four fairy tales to describe how humans might impact the climate by the year 2100.
There was an optimistic scenario, two mid-range scenarios, and a pessimistic scenario.
The latter is known as RCP8.5 (I think of it as Ridiculous Climate Prophesy 8 dot 5).
In January, Zeke Hausfather and Glenn Peters published a comment in Nature reminding everyone that RCP8.5 isn’t a realistic vision of the future.
It represents an unlikely, high-risk, dystopian world (their words) in which “the dice are loaded with the worst outcomes.”
It can’t become reality, they point out, unless humanity burns five times more coal than we currently do, “an amount larger than some estimates of recoverable coal reserves.”
Whenever RCP8.5 gets mentioned, they say, it should be clearly labeled as an “unlikely worst case.”
Their plea is unmistakable:
We must all – from physical scientists and climate-impact modellers to communicators