May 2026 at THB
A big month, here’s a review
In May I continued to discuss the official retirement of RCP8.5. I also shared our new research on demographic forecasting, took a look at institutional partisan advocacy, and highlighted John Stossel’s excellent video on my departure from academia. Below are links and capsule summaries.
In the coming weeks I’ll be posting the next THB Deep Dive looking at ENSO and its relationship with U.S. hurricanes, global disaster losses, and Colorado River streamflow. I’ll also be sharing a new preprint (with Jessica Weinkle) that updates our time series of normalized continental U.S. hurricane losses. June will be fun — but before all that, let’s look back at May.
“The World’s Most Important Science Advisory Committee” mapped the governance architecture of an obscure science committee that controls which scenarios enter climate modeling. Few people know anything about this committee, who is on it, what organizations it reports to, or who funds it. The governance of climate-research-for-policy is problematic, to say the least.
In the weeks following RCP8.5 RIP there was near-silence from mainstream U.S. media outlets. That changed in a hurry when Donald Trump posted about it near the end of the month. But before Trump’s post, the biggest story in climate science in years received almost no coverage.
This post summarized the 2021 paper — by me and Justin Ritchie — documenting how RCP8.5 (and more generally the RCPs and SSPs) emerged from a suite of mistakes and confusion setting the stage for the scenario mess that the climate community now finds itself in. These problems are not solved. Tip for new readers — start here for background on climate scenarios which I’ve been discussing here at THB since the beginning.
Spinmeisters have been hard at work trying to invent an alternative history: Specifically, that policy progress — not flawed theory and faulty assumptions — were the reason for the RCP8.5 retirement. Improving climate research and its use in decision making depends in no small part in accurate and honest understandings of how we got to today. The evidence in this post is irrefutable — That is why no one has even tried to refute it.
Trump’s post on RCP8.5 got one thing correct — RCP8.5 was WRONG! But pretty much everything else in his post was false. The first wave of U.S. media coverage followed Trump’s lead by reporting on RCP8.5 with many false claims. This post documents some of those false assertions. I do want to acknowledge that later coverage was better, and the New York Times, in particular, had a very good second story on RCP8.5.
This post looks at the increasingly partisan posture that major scientific institutions adopted after 2016, and takes a close look at new research that deepens our understanding of the consequences of Nature’s presidential endorsements in 2020 and 2024. Not surprisingly, the endorsements didn’t have any effect on how people voted, but they did lead to a loss of public trust in science — not just among those on the political right, but among moderates as well. Leaders of science institutions should pay close attention.
This post introduced a new preprint co-authored with Samuele Lo Piano, Marta Kuc-Czarnecka, and Andrea Saltelli. The central finding: model choice — not parameter uncertainty — accounts for almost all of the variance in long-run population projections. The model you pick determines the answer far more than any technical assumption you make within it. That has important implications for those who use population projections (including climate modelers), and we suggestion some guidelines for their use.
John Stossel’s short account of some of my experiences that led me ultimately to choose to leave academia is very well done. Newer readers wanting background on how I got to where I am today, and why I’d do it all over again — start with this one.
Comments, suggestions, requests — All welcome!
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This has been a dynamite month, Roger Only problem is, now your faithful readership will expect every new month to be this explosive!! Just kidding. Write about whatever interests you, however arcane. We will happily read along, slurping up the tidbits like the knowledge truffle hounds we are.
Thank you for continuing your research focused on the truth. You are more gracious than I could be if I had been attacked as you were. Your writing and research is very helpful and informative. Those who disagree have to be open to learning if they want to improve their understanding of your research. Unfortunately, for some it is a game of power and your research is inconvenient. I look forward to many more years of reading your SubStack and the linked articles and research.