At first I was surprised, because it wasn't awarded to anyone in fundamental physics research, as usual. But then I realized it made perfect sense, and sends an important message as well, and just before COP26.
I'm more familiar with Manabe's work than the other two. In fact, a few years ago I wanted to profile Manabe for Yale Climate Connections, but he wouldn't do an interview. Beforehand I had read some of his early papers with Richard Wetherald -- Manabe did the physics, Wetherald did the computer programming -- such as this famous 1967 paper, and they were remarkably well written and exceptionally clear.
Here's a 1989 oral interview of Manabe by Spencer Weart of the American Institute of Physics.
And, let's say it: Manabe and Klaus Hasselmann, who also built climate models, were right in their predictions -- they correctly predicted the Earth's response to increasing carbon dioxide in the atmosphere. Here's a nice evaluation of Manabe and Wetherald's 1967 result: they predicted a CO2 climate sensitivity, when CO2 goes from 300 ppm to 600 ppm, of 2.4°C,
which is in today's range of 1.5-4.5°C. just shy of AR6's range of 2.5 - 4.5°C.
And, as that blog post notes, they made their prediction in 1967, at a time when the Earth's surface temperature was in a slight 20+ year cooling period. But they got a bit lucky -- if that cooling period was caused by atmospheric aerosols -- air pollution from vehicles, mostly -- they couldn't have known it would be cleaned up by the proliferation of clean air laws in the 1970s in the US and Europe.
I don't know as much about the work of Klaus Hasselmann and Giorgio Parisi, but am looking forward to learning more today.
A very thoughtful Prize.