Ok, so I have now gone through two MOOC courses on climate change, the older David Archer Coursera course and Michael Mann edX course, and I have some recommendations for my fellow non-climate scientists.
First, absolutely do take a course. Yea, I know, our own areas of science are enough of a struggle, and we are each unlikely to become climate activists. This is, however, the preeminent scientific moral issue of our time, and it is not going away in your lifetime.
Your training lets you understand the physics, the evidence, and the uncertainties at a level that most can't. That gives you the responsibility to apply your abilities to every climate news story and every dumb internet or Thanksgiving table argument, even if only for yourself.
You still won't know very much - your own field can't be mastered in 1 internet course or 20 - but a little knowledge and physical understanding can let you brush away so much nonsense, and opportunities to use your insight for good may find you. You'll have a long time to see.
Superficially the Archer course and the Mann course look similar. They cover mostly the same topics, involve a combination of lectures and quiz or exam questions, and both are free if you do not wish to pay a little extra for a certificate. They are actually very different.
The Mann Course is shorter, nominally eight weeks, which means a scientist can complete it in a weekend. Each short video chapter is followed by "Comprehension Questions" that are essentially "Were you listening?" and the midterm and final are similar. The course should be
readily accessible to educated non-scientists or even good high school students. In retrospect I regret not going through the course with my 11-year old, though I would have had to explain some things such as isotopes or a derivative symbol for rate of change.
The ease shouldn't fool you though; there is a lot of physical knowledge presented, and a scientist will likely appreciate many subtleties, as well as gloss-overs of topics that couldn't be explained fully in the targeted time/level.
The Archer Coursera course is nominally 12 weeks and in reality it is about twice as much work as the Mann course. That means that it may take you an evening session each night for most of two weeks. The "Quiz" assignments are mostly not quizzes at all, but rather resemble
conventional STEM homework problems or involve online "labs" where simulations must be explored to arrive at a solution. This is all doable, but it isn't trivial. The course is far more physical and mathematical (though never in a difficult way) than the Mann course, it takes
the time to work through the details, and its homework-quizzes are aimed at promoting a far deeper understanding. No 11-year old could touch it, but it might be good college prep for a strong senior in high school planning a STEM major.
Most of all, from the perspective of a scientist the Archer course is just intellectually _satisfying_. By working through the details and doing calculations and simulations yourself, you feel that you get it, that you have learned so much more than just a list of facts.
The Mann course doesn't really quite succeed in that way, and neither will any article or ordinary book. As scientists we understand the difference in feel between popular science we have read and science we have ourselves done, and the Archer course approaches the latter.
OK, so with apologies to @MichaelEMann, I have to recommend that physically oriented scientists take the Archer course. For non-scientists, or if you can't devote the time, the Mann course is certainly terrific and well worth the effort.
