Although I find this a rather uncomfortable topic, I thought it well worth highlighting an article by Piers Sellers in which he discusses his thoughts about climate change, given that he has just been diagnosed with Stage 4 pancreatic cancer. As an aside, Piers Sellers is a graduate of the University at which I now work.
It’s a powerful and poignant essay in which he, after thinking about the position he was in,
….found out that I had no desire to jostle with wealthy tourists on Mount Everest, or fight for some yardage on a beautiful and exclusive beach, or all those other things one toys with on a boring January afternoon. Instead, I concluded that all I really wanted to do was spend more time with the people I know and love, and get back to my office as quickly as possible.
As you might imagine, however, Watts Up With That has a post (archived here) objecting to a scientist using their dire personal health issue to promote their views about climate science; Science is supposed to be about reason, logic and evidence, not desperate appeals for sympathy. In my view, not only is this an entirely unreasonable interpretation of Piers Sellers’s article (although not as bad as some others that I won’t even bother Archiving) since Piers Sellers doesn’t say anything that isn’t widely accepted, by scientists and policy-makers, it’s also a simplistic interpretation of the role of science and scientists.
Researchers should, of course, aim to be objective and unbiased when doing their research and when presenting it in a formal setting. However, they have no obligation to do so when engaging with the public in their personal capacity. Not only are they both scientists and members of the public, what’s the point of investing in research, if those who understand it best are discouraged from publicly discussing the implications of what it suggests. As I’ve said before, I’m – of course – not suggesting that scientists/researchers should have some kind of special place when it comes to making decisions, I’m simply suggesting that the public benefits from experts expressing their views as to the significance of their research.
I won’t, however, say more about this aspect of the article (although feel free to express your views in the comments), but there was one thing in the article that I thought I would highlight. Piers Sellers says:
It’s doubtful that we’ll hold the line at 2 degrees Celsius, but we need to give it our best shot. With scenarios that exceed that target, we are talking about enormous changes in global precipitation and temperature patterns, huge impacts on water and food security, and significant sea level rise. As the predicted temperature rises, model uncertainty grows, increasing the likelihood of unforeseen, disastrous events.
It’s really this last sentence that I think is interesting and is maybe an under-appreciated point; although it is related to the uncertainty isn’t your friend point that both Victor Venema and Michael Tobis have discussed before.
We can think of what we’re doing as perturbing the natural greenhouse effect. The natural greenhouse effect essentially warms the planet by 33K. Our actions over the last 150 years, or so, has warmed it by about another 1K. Although our climate is clearly a very complex, non-linear, system, if the perturbation is reasonably small, we can have some confidence that the response will be linear, and that we can predict what will probably happen. Our confidence, however, decreases as the perturbation grows. As a rule of thumb, we might expect the response to become increasingly non-linear for perturbations of about 10%, or larger; i.e., warming of about 3K, or more.
So, one might reasonably argue that the closer we get to a perturbation of 3K, or higher, the harder it will be to confidently predict the response, and – hence – the more likely it becomes that we will encounter unforeseen, disastrous outcomes. That’s not to say that less than 3K will be fine, but simply that the larger the perturbation, the greater the risk of outcomes that we didn’t expect and that may have extremely damaging consequences. I think this is something that we should be taking into account, and it reminded me of the video below, which I’ve mentioned before, but which is worth posting again. The reason is mainly to highlight what Richard Alley says at 6:05
so when we look at climate change; best estimate; a little better; a little worse; a lot worse….the uncertainties are mostly on the bad side