Serendipity

I’m giving a talk today to a group of high school students. Most of the talk focusses on climate models, and the kinds of experiments you can do with them. But I thought I’d start with a little bit of history, to demonstrate some key points in the development of our understanding of climate change. Here’s some of the slides I put together (drawing heavily on Spencer Weart’s the Discovery of Global Warming for inspiration). Comments on these slides are welcome.

I plan to start with this image:

…and ask some general questions like:

• What do you think of when you see this image?
• Where did all that energy come from?
• Where does all that energy go? (remember, energy cannot be created or destroy, only transformed…)
• What happens when you add up the energy needs of 6 billion people?
• and, introducing the spaceship earth metaphor: Who’s driving this spaceship, and are the life support systems working properly?…

For millions of years, the planet had a natural control system that kept the climate relatively stable. We appear to have broken it. Now we’ve got to figure out how to control it ourselves, before we do irreversible damage. We’re not about to crash this spaceship, but we could damage its life support systems if we don’t figure out how to control it properly.

I then show some graphs showing temperature changes through pre-history, together with graphs of the recent temperature rise. As a prelude to a little history. Here’s my history slides: