To stop global warming, why not just turn down the Sun?
It would be easy to do -- but insanely risky. Even so, the idea seems likely to grow in popularity, as it aligns with the needs of the oil industry and pushes our urgent problems into the future.
Environmental writer Bill McKibben recently published an excellent article in the New Yorker looking at scientific research and shifting attitudes on geoengineering. The term refers to a variety of techniques humans might possibly use to “engineer” our way out of the problem of global warming, or, at least, to mitigate its near-term consequences. If we can’t reduce greenhouse gas emissions quickly enough, the idea goes, we need a Plan B — some other way to intervene to stave off the worst consequences of our failure. If we can’t manage real action on global warming, maybe we can organize some global cooling to counteract it — a neat technical fix!
There are a variety of ideas about how one might pull this off, but the simplest and most often discussed — and McKibben’s focus in his article — is so-called “solar radiation management.” Our emissions of greenhouse gases have caused an imbalance in the energy budget of the Earth — more is coming in from the Sun than is going out — causing planetary warming. One obvious countermeasure would be to adjust the amount of solar energy coming into the Earth, thereby restoring the balance.
How? Well, we can’t easily turn down the Sun as a thermonuclear fusion reactor, but we can influence how much of its energy actually reaches the Earth’s lower atmosphere and surface, where it can be absorbed. Just inject lots of particulate matter such as sulfur dioxide into the upper atmosphere where it will act to reflect sunlight back to space, cooling the planet below. This is what happens when volcanoes erupt and such events have had marked effects in temporarily reducing global temperatures. For example, the 1991 eruption of Mt. Pinatubo in the Philippines caused a drop of more than 0.5°C in average global temperatures over the next 15 months.
Although it sounds like a truly massive undertaking, such a project would actually be relatively easy to achieve — probably within the capabilities of many small nations with a few aircraft. Even a single super wealthy individual might do it (this is a disturbingly plausible scenario). One thing McKibben’s article usefully explores is how such an approach may go awfully wrong, and actually trap us in an even worse predicament.
Yet the article also examines the growing psychological momentum behind this idea, even among those people most concerned with global warming. On this, I think McKibben is almost certainly right that — despite the many risks and likely awful side effects of taking this approach — solar radiation management is a pathway we’re likely to follow. Not because it is a good idea, or will solve our problems, but merely because it is a relatively easy option.
More importantly, it’s an option likely to be favored by the one group which has so far exerted the most profound influence over energy policy in the recent past — the fossil fuel industry itself. Based on their past behavior, fossil fuel interests will likely act in favor of any technological approach to global warming which will enable their profiting from the continued extraction and burning of fossil fuels, despite the consequences for everyone else.
Why is solar radiation management risky? Several reasons. For one, if we take this approach, it’s not something we can just do for a short time and then stop. Particles injected into the atmosphere only stay there a short time — sulfur dioxide for about 10 days, other particles up to a year or so — and we’ll need to keep replenishing them to preserve temperatures. Indeed, if greenhouse gas emissions continue to grow, as well they might, we’ll be locked into a schedule of ever rising particulate injections just to keep pace with rising greenhouse gas concentrations and preserve the climate.
If, for whatever reason, we were to eventually stop injecting particulates, we would then be hit with very rapid warming, as the planetary energy balance would be much larger than it is today. Hence, using solar radiation management makes the climate problem more unstable, turning it into a problem requiring active ongoing control to avoid disaster. In particular, scientists argue that the rapid warming of such an episode would have terrible consequences for biodiversity, as many species would not be able to adapt to such rapidly rising temperatures.
It’s also true that solar radiation management would not simply “undo” the warming problem. Rather, it would only partially counter one effect of greenhouse emissions — rising temperatures — leaving many others untouched. The seas will continue to grow more acidic. Even with regard to temperatures, the effects of particulate injection will be unpredictable and likely help some nations more than others, while causing harm in the sense of prolonged droughts or extreme weather events in other nations. There’s huge potential for geopolitical conflict over the different consequences of such climate fiddling.
Weirdly enough, these and other negative aspects to the use of solar radiation management cause many of the people closely involved in researching its likely consequences to be strongly against it’s ultimate use. As McKibben notes, almost all of the people he spoke to who are working toward making this kind of geoengineering more plausible actually think its a bad idea:
Everyone studying solar geoengineering seems to agree that it’s a terrible thing.
“The idea is outlandish,” Parker told me. Mohammed Mofizur Rahman, a Bangladeshi scientist who is one of Degrees Initiatives’ grantees, noted, “It’s crazy stuff.” So did the veteran Hungarian diplomat Janos Pasztor, who runs the Carnegie initiative on geoengineering governance, and said, “People should be suspicious.” Pascal Lamy, a former head of the World Trade Organization (W.T.O.), who is the president of the Paris Peace Forum, agreed, saying, “It would represent a failure.”
Jesse Reynolds, a longtime advocate of geoengineering research, who launched the forum’s commission, wrote recently that geoengineering’s “reluctant ‘supporters’ are despondent environmentalists who are concerned about climate change and believe that abatement of greenhouse gas emissions might not be enough.” Reynolds speaks for this geoengineering community on this point. They are, to a person, willing to acknowledge that reducing emissions by replacing coal, gas, and oil represents a much better solution. “I think the basic answer is moving more rapidly out of fossil fuels,” Lamy said.
I’m sure all these people have the best of intentions, and they truly hope their contributions will lead to solutions for our planet. And yet, I also think there’s a certain naivete in their activities.
They’re exploring something they really hope won’t be used, but ironically, in the process, probably making its eventual use more likely.
As a team of scientists argued a few years ago, this and other geoengineering approaches to the global warming problem are like temporary bandages which tackle some symptoms of an underlying problem, but don’t touch the source of the problem itself. Effective solar radiation management would, paradoxically, remove all the pressure on the global economy to reduce use of fossil fuels. It might make the problem worse, not better.
Moreover, it would do nothing at all to address the deeper problem of reducing humanity’s ever-growing impact on the planet, which has already exceeded several safe boundaries within which we can be relatively assured that the biosphere will remain stable. Indeed, it would only increase such impacts. By hiding these and related issues behind a satisfying blaze of technical wizardry, technological patches of this sort will only steer people away from pursuing difficult social and economic change.
And, for that reason — cynic that I am — I’m convinced this it’s also likely that this is precisely what people will choose to do, at least for a short while, until this approach causes even greater problems, and brings more pain. Moreover, the most powerful interests opposing action on carbon emissions will likely find geoengineering increasingly attractive, and aim to push the public along this easy axis.
If you think I’m being too cynical, then see Emily Atkin’s recent examination of deceptive efforts by conservative groups in California to undermine progress on developing offshore wind energy — by arguing they will damage the environment! Given the past accomplishments and the ample resources of fossil fuel interests and their political allies, their influence could be considerable and perhaps decisive.
I think we’ve moved beyond the state where we could believe, naively, that policy will eventually be determined by scientific logic and good sense. More likely, it may well hang on little more than the ability of well-funded groups to effectively shape public opinion in pursuit of their purely short-term interests. At least, this seems likely in the absence of something like an unprecedented massing of public outrage on a global scale, something far beyond anything seen so far in our human history.
Without such an event, the best intentions of scientists hoping to provide a plan B for humanity may well be hijacked by forces interested only in profiting from the continued use of fossil fuels, long-term consequences be damned.