The growing interest in studying the potential of these tools, particularly through small-scale outdoor experiments, has triggered corresponding calls to shut down the research field, or at least to restrict it more tightly. But such rules would halt or hinder scientific exploration of technologies that could save lives and ease suffering as global warming accelerates—and they might also be far harder to define and implement than their proponents appreciate.
Earlier this month, Tennessee’s governor signed into law a bill banning the “intentional injection, release, or dispersion” of chemicals into the atmosphere for the “express purpose of affecting temperature, weather, or the intensity of the sunlight.” The legislation seems to have been primarily motivated by debunked conspiracy theories about chemtrails.
Meanwhile, at the March meeting of the United Nations Environmental Agency, a bloc of African nations called for a resolution that would establish a moratorium, if not a ban, on all geoengineering activities, including outdoor tests. Mexican officials have also proposed restrictions on experiments within their boundaries.
To be clear, I’m not a disinterested observer but a climate researcher focused on solar geoengineering and coordinating international modeling studies on the issue. As I stated in a letter I coauthored last year, I believe that it’s important to conduct more research on these technologies because it might significantly reduce certain climatic risks.
This doesn’t mean I support unilateral efforts today, or forging ahead in this space without broader societal engagement and consent. But some of these proposed restrictions on solar geoengineering leave vague what would constitute an acceptable, “small” test as opposed to an unacceptable “intervention.” Such vagueness is problematic, and its potential consequences would have far more reach than the well-intentioned proponents of regulation might wish for.
Consider the “intentional” standard of the Tennessee bill. While it is true that the intentionality of any such effort matters, defining it is tough. If knowing that an activity will affect the atmosphere is enough for it to be considered geoengineering, even driving a car—since you know its emissions warm up the climate—could fall under the banner. Or, to pick an example operating on a much larger scale, a utility might run afoul of the bill, since operating a power plant produces both carbon dioxide that warms up the planet and sulfur dioxide pollution that can exert a cooling effect.
Indeed, a single coal-fired plant can pump out more than 40,000 tons of the latter gas a year, dwarfing the few kilograms proposed for some stratospheric experiments. That includes the Harvard project recently scrapped in light of concerns from environmental and Indigenous groups.
Of course, one might say that in all those other cases, the climate-altering impact of emissions is only a side effect of another activity (going somewhere, producing energy, having fun). But then, outdoor tests of solar geoengineering can be framed as efforts to gain further knowledge for societal or scientific benefit. More stringent regulations suggest that, of all intentional activities, it is those focused on knowledge-seeking that need to be subjected to the highest scrutiny—while joyrides, international flights, or bitcoin mining are all fine.
#proposals #restrict #geoengineering #misguided
