I wanted to post this video (see end of post), that I first came across in this comment (H/T Pehr Björnbom). It’s a few years old, so some things may have changed, but it’s still mostly relevent.
It’s a discussion between Kerry Emanuel (Professor of Atmospheric Science at MIT) and John Christy (Distinguished Professor of Atmospheric Science at the University of Alabama, Huntsville), moderated by Russ Roberts.
John Christy promoted a great many of what I would normally call “skeptic” themes. Fossil fuels are, and will continue to be, the most reliable and economically viable energy source, climate has always changed and there is nothing special about today’s changes, models have projected much more warming than has been observed, and we can’t tell how much of the recently observed warming is natural, and how much is anthropogenic.
Without a carbon tax, his first point may well end up being right. However, the same can’t be said for the rest of what he promoted. The climate has indeed always changed, but studying these past changes has played a key role in understanding what’s causing it to change today (mostly us). When comparisons are done carefully, models actually compare well with observations (should also be careful to ensure that the comparison is really like-for-like). We actually can disentangle how much of the observed warming is natural, and how much is anthropogenic. The best estimate is that we’re responsible for slightly more than all of it.
Kerry Emanuel highlighted that the basics have been well understand since the 19th century, and that a key thing is that this is mostly about risk. We are taking a risk with our climate by emitting CO2 into the atmosphere; doing so will change our climate, these changes could be substantial and the impacts of these changes could be severe, potentially catastrophic. Of course, there are also risks associated with what we might do to address this. Hence, this is not simple and we should think about this rationally.
What I found quite interesting was how Kerry Emanuel approached the discussion. It was very measured and thoughtful and he regularly broadly agreed with what John Christy was saying. Observations are not perfect, climate models do have problems, there is a lot of uncertainty, etc. However, he kept going back to the basics and highlighted that even though we can’t be certain as to what will happen, we are still taking a risk.
I partly thought that this was quite good as it came across well, but I wondered how it would be perceived by a more neutral observer, or by those who are already doubtful. It’s possible that they would walk away thinking that the doubts are quite justified and that maybe there isn’t really any reason to do anything just yet. On the other hand, I don’t really know how else to approach this kind of discussion. Being more confrontational may well come across poorly and be ineffective. I think it mostly highlights how difficult these kind of discussions can be. Anwyay, I’ve said more than enough. Video below.