The results are in: discussing solar geoengineering doesn't undermine emissions cuts

[Andrew Lockley]

https://peteirvine.substack.com/p/the-results-are-in-discussing-solar?utm_source=%2Finbox&utm_medium=reader2

Plan A+

The results are in: discussing solar geoengineering doesn't undermine emissions cuts

There have been over a dozen public perception studies on solar geoengineering, and they are clear: the fear that motivated the taboo on solar geoengineering research was unfounded.

Pete Irvine

7 hr ago

About a year after I started my PhD in 2009, I was invited to be an expert at a public dialogue on carbon dioxide removal and solar geoengineering. The UK was considering launching a research effort and wanted to know what the public thought about it [1].

Experiment Earth?

Figure 1. The logo for NERC’s “Experiment Earth?” public dialogue

The participants were given an overview of all the various ideas and then asked to discuss them with the help of a moderator. Generally, the more "natural" a proposal seemed, the more supportive the public was: afforestation was very popular, stratospheric aerosol geoengineering was not. But, while the participants were concerned about many of the ideas, they were very supportive of research.

Something that stuck with me was that an older guy took me aside and asked: "Are scientists seriously thinking about this? Wow, climate change must be worse than I thought." I got the sense then that this was a widespread feeling.

Breaking the taboo

The Royal Society had recently published a report recommending that a major research effort into carbon dioxide removal and solar geoengineering begin and the UK’s research councils wanted to check that the public would support this research. They concluded that they did and so they launched the world's first nationally-funded research effort.

These ideas hadn't just occurred to scientists in the late 00’s, many of them had been around for decades, but they had been suppressed for fear of distracting the public and policymakers from cutting CO2 emissions [2]. It took the intervention of Paul Crutzen, winner of the Nobel Prize for his work on the ozone layer, to break this taboo [3].

16 years on from Crutzen's intervention it seems clear that the fear that motivated this taboo on solar geoengineering research was unfounded.

Moral hazard

Many reasonable people oppose solar geoengineering on the grounds that it might undermine mitigation efforts, delaying the date that we achieve desirable cuts in emissions. This potential delay is known as the moral hazard effect or mitigation deterrence effect of solar geoengineering.

There’s a lot to say about this idea, but I think a useful place to start is to distinguish a strong and a weak moral hazard objection to solar geoengineering research:

Strong: "Discussion of solar geoengineering will lead to a reduction in emissions cuts"

Weak: "Implementation of solar geoengineering will lead to a reduction in emission cuts"

While it's obviously too early to know much about the effects of implementing solar geoengineering on climate policy, we're now in a position to dismiss the strong moral hazard objection to solar geoengineering research.

The results are in

So far there have been 13 social science studies that can shine a light on this issue (see the Appendix). Only one study, Raimi et al. (2019) found a reduction in support for emissions policies after telling their participants about solar geoengineering, and they only got that result when solar geoengineering was 'described as a "great" solution to climate change, one in which "we wouldn't have to do much more to stop the worst effects of climate change."' In their other 2 framings of solar geoengineering, they found no statistically significant effect on support for emissions policies.

For the other studies, 7 found either no significant effect or no evidence for a moral hazard effect, and 5 found an inverse moral hazard effect, i.e., exposing people to the idea for solar geoengineering increased their apparent willingness to cut emissions. Merk et al. (2016) was the first study to document this inverse moral hazard. For their study, they gave 650 German participants 10 euros each, gave them some reading, surveyed them, and then offered them the option to buy subsidised carbon offsets. Some were told about stratospheric aerosol geoengineering and others weren't. Those who were spent 15% more on carbon offsets than those who weren't. This wasn't simply virtue signalling, they spent real money.