Still the first day

Well, I've watched a video about how greenhouse gases trap heat in the atmosphere, and why a better term might be the "blanket" effect. And read Tim's article about the various greenhouse gases, how prevalent they are and how effective at retaining heat. Complete with a scan of a 1912 newspaper article describing the effects of adding carbon to the atmosphere as CO2.

Lots of student comments to read, far more than anyone could absorb in the time. But I've skimmed all the discussions so far, and added a few comments and replies of my own.

What have I learned so far? Mostly that my understanding of how a greenhouse works was flawed (it's mainly about convection and shelter from colder outside air), and also that it is not a very good metaphor for the warming effects of human activities on the planet anyway.

I've also learned that there are some very well informed and interesting people taking the course.