That’s the gist of what Swiss climate scientist Sonia Seneviratne told CBC News about why she may refuse to participate in any future assessment reports from the UN Intergovernmental Panel on Climate Change (IPCC).

It’s not that the reports don’t let her say what she wants to say. She’s been a lead author about extreme weather in three of the six assessment reports.

No, it’s that policymakers around the world don’t just take her word for it and do what she says must be done.

“There is no point for us to just observe what a disaster is unfolding if nobody is doing anything about it,” she says.

What Seneviratne forgets—or perhaps doesn’t understand—is that policy, no matter the subject, has to take into account all kinds of things, not just science, even the most objective and cool-headed (let alone the subjective and hot-headed science that drives warnings of catastrophic manmade global warming).

Policymakers—presidents, parliamentarians, bureaucrats, state and provincial governors, mayors and city councils—have to think not just about the results of some equation purporting to show how much global average surface temperature will rise, and by when, in response to an incremental rise in atmospheric CO2 concentration. They have to think about tradeoffs. What we spend on X we can’t spend on Y. The effort we make to curtail a fraction of a degree of warming is effort we can’t make to lift a hundred million people out of poverty. And, who knows? Maybe their poverty is a greater risk to them than that fraction of a degree of warming.

Seneviratne appears blind to the fact that while science can (to varying degrees of accuracy and confidence) tell us what’s happening, it has no special knowledge about what ought to be done about it. From what is, you cannot derive what ought to be.

Photo by Yoyo Hins on Unsplash.