Tuesday, October 05, 2021

Nobel Prizes for Climate Science

Today's Nobel Prizes in Physics goes to three men who played very important roles in the early development of climate science and the analysis of complex dynamical systems. Quanta magazine has a good summary

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.

2 comments:

JoeT said...

It's funny, I was trying to remember what the web site was of the guy who had those great graphs about climate sensitivity, but I couldn't remember the name. You just linked to it, so thanks.

In particular I was trying to remember the argument why the slope yields ECS rather TCR for something I was writing. It's there in a citation about Isaac Held. One interesting thing is that in the last IPCC report, the uncertainty in ECS was reduced from 1.5 - 4.5 to 2.5 - 4.0.

David Appell said...

Joe, thanks for correcting me on the latest ECS -- I'll note that in my post.