It seems the latest controversy in the climate debate is whether or not we should be studying Solar Radiation Management (SRM). As Stoat points out, there is a new National Academy of Sciences report on Reflecting Sunlight, which seems to have divided some people. It turns out, I also have a previous post about Solar Radiation Management.
There seem to be two related criticisms of SRM. One is that studying SRM might be seen as promoting an alternative to actually reducing emissions. SRM researchers do, though, make clear that they’re not proposing SRM as an alternative. The other issue is that SRM, itself, might be risky. It works by reflecting sunlight, which will clearly lead to cooling. However, it doesn’t exactly reverse global warming, so there are potential effects that are possibly difficult to predict. It also does little counter ocean acidification. Additionally, if the impact of SRM is large, there’s the risk of what is called a termination shock if the SRM level isn’t maintained.
On the other hand, if we don’t study SRM and we end up in a situation where we might want to seriously consider some kind of geo-engineering solution, we could end up using something like SRM without having a particularly good understanding of the potential impact. Also, as Andrew Dessler has argued, if we do think that negative emission technologies are viable, then SRM could be used to suppress a relatively small amount of global warming, until negative emissions technologies can be implemented at a suitable scale.
As a researcher, I tend to be biased in favour of understanding things. However, I’m also in favour of being aware of the potential implications of developing that understanding. When the research is specifically aimed at understanding a technology that we could end up developing, then I do think it’s important to have some kind of governance arrangement. Partly because I don’t think it’s the researchers alone who should be making these decisions, and partly because I don’t think it’s in their interests to do so.
So, I am generally in favour of studying SRM but I am slightly concerned that some of the narrative is shifting towards being more positive about its use, which I do not think is a good thing. I still think that we should be prioritising emissions reductions and that SRM should not be something that we should be seriously considering. Maybe there will come a point where we might consider implementing it, but I don’t think we’re anywhere close to that yet.Links:
Reflecting Sunlight – Stoat’s post.
Solar Radiation Management – a previous post of mine about SRM.