I was surprised when reading the letter “Climate at Reunions” (Inbox, October issue) with the claim of several “absurd propositions” made by speakers at the recent Reunions panel “Why Climate Change is NOT an Emergency.” Nothing I heard was “absurd.” For example, nowhere was it claimed that sea levels aren’t rising globally. Ironically, the authors said that “University-affiliated scientists” should be represented, when one of the speakers, William Happer, was not only a student at Princeton (*64), but also Cyrus Fogg Brackett Professor of Physics at Princeton from 2003 until his retirement in 2014.

Unfortunately, climate science is monumentally complex, and what “answers” there are come with huge uncertainties. A good starting point for greater understanding is the recent book Unsettled? (2021), by Steven Koonin (former theoretical physicist at Caltech, later Provost there, and Second Under Secretary for Science in Obama’s energy department with over 200 peer-reviewed papers on scientific computation, climate modeling … I could go on) who says that the core questions related to human input to and influence on the climate remain largely unsettled.  In particular, he shows that climate models, which represent the entire basis for predicting future temperatures, vary widely. Furthermore, he says that the uncertainty in model outputs has been increasing even as computational systems become more powerful! Consequently, he says, “in terms of providing actionable information, they’re not much good at all.” As far as the “existential threats” we hear about, he notes that even in the most recent “IPCC report that just came out in August [2021, 6th Assessment], you don’t find the words ‘climate catastrophe,’ ‘existential threat,’ or ‘climate disaster’ in it at all. You find ‘climate crisis’ once in the report, and that refers to how the media have dumbed down the description rather than any scientific finding.” For an in-depth interview with him on the specific question of “climate emergency” see the Hoover Institution’s Uncommon Knowledge podcast.

Professor Koonin is just one of many scientists with similar, indisputable climate and meteorological expertise, having similar viewpoints. Unfortunately, such views rarely get aired, which is precisely why panels like that at the recent Reunions serve an important purpose.

Greg Nash ’68
Los Angeles, Calif.