MOOC reflections

I'm three weeks into David Archer's Coursera course Global Warming: The Science and Modeling of Climate Change. There were several reasons I signed up for the course:

• I'm interested in understanding climate science better, and this seemed a better way to get a first-shot overview than diving straight into a textbook like Pierrehumbert's Principles of Planetary Climate or Kaper and Engler's Mathematics and Climate.
• I wanted to see whether there were ideas (both in terms of content and of teaching methods) that I could borrow for my Mathematics for Sustainability course next semester.
• And, I had never taken part in a MOOC (massive online open course) and I was interested to see what the experience is like.

 So, three weeks in, how is it going?  A few thoughts.

•  This would be a great course for someone to take who wanted to understand a bit more about the complications of the Earth's climate system and the way in which scientists try to model it.  I knew a reasonable amount about the material before I started and in pretty much every video I can feel connections being made, understanding dawning of the way different phenomena are interrelated.   
• The course is fast-moving.   Be prepared for a workout if you take it! 
• Having homework assignments and "instant feedback" quizzes is crucial to maintaining interest, even for a highly motivated student as I fondly imagine that I am.  I seem to be maintaining a reasonable homework average - though I have not yet figured out how "peer assessments" are supposed to work.
• The sheer variety of different effects, on different spatial and time scales, that need to be modeled is quite overwhelming.   It is hard (for me as an outsider) not to suspect that there might easily be other effects, of a similar order of magnitude, which nobody has thought about yet.  This may inspire some skepticism about specific numerical answers, but it is not a reason for complacency.  If the effects that we can reasonably model add up to a significant perturbation of our present climate, it would be the height of foolishness to hope that the effects we have until now forgotten will exactly conspire to cancel out that perturbation!
• The quantitative problems seem to me to offer a good blend of "bare hands" estimates and problems that require the student to use a "black box" climate model.  I am interested in maybe providing such "black box" models for various things in the Math for Sustainability course.  This would require a lot of thought about how these models are to be served, scalability, reliability, etc.
• Each week also has an "Explainer" problem where you are required to explain some course concept.  The limits are that you have 400 words maximum and the explanation must be understandable by an 11-year old.  (I don't know if they have any actual 11-year olds grading to check.)   This is an interesting and challenging assignment. 
• I have not made any use of the online discussion fora for the course.  

Image: Logo for the course, screengrab from Coursera