Mathematics of Planet Earth

I mentioned a few days ago that i was planning to give a talk on "The Mathematics of Planet Earth" to the Penn State student math club, and this duly took place last week. There was a good crowd, including a few students from my Math 230H course lat year, and a group from the local chapter of Engineers for a Sustainable World. I was encouraged by the turnout - and still more so (though a little scared) by a couple of requests that the lecture be posted online. So, above is a link to a YouTube video (in five parts) of the event.

I probably (okay, definitely) tried to say too much.  There were three points I wanted to make:

1. The paradigm shift from "empty world" to "full world", and mathematical ways of understanding that.
2. Pretty simple calculations can help us get a feeling for the magnitudes of the challenges ahead - I tried to illustrate that by doing some global warming calculations, though I maybe included too much chemistry (one person walked out when I put up the hydrocarbon combustion formulae, but maybe that was unrelated)
3. There are contributions mathematics can make through education and through research (probably the weakest part of the talk, partly through time pressure, partly because some of my ideas were a bit unfocused).

You might recognize some of the ideas from "Do the Math" and "Azimuth", which I've mentioned many times before, being used in this talk.  I still feel I'm developing a personal way of speaking about these matters.  Having brooded about them for a while, it is hard not to want to say everything at once when one does get an opportunity to talk!