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Geoengineering is risky and unproven, but soon it might be necessary

This article is part of Troubleshooting Earth: a multi-part series that explores the bold, innovative, and potentially world-changing efforts to wield technology as a weapon against climate change.

Imagine the azure blue skies of summer fading to a hazy white as light-scattering aerosols are injected into Earth’s upper atmosphere. Imagine a planet covered with giant artificial chemical sponges leeching gases out of the air that we breathe. Imagine filling the Earth’s oceans with millions of pounds of calcium bicarbonate to alter the levels of acidification.

On paper (or, well, on screen) these suggestions smack more than a little of the more apocalyptic, megalomaniacal James Bond movie plots of the 1970s.

NASA Earth Observatory

In a sense, they’re not all that different. All of them are initiatives proposed with the express goal of modifying our planet’s complex “earthsystem” on a massive, global scale. Only, unlike the sinister population-destroying efforts of the Bond baddies, this type of modification — referred to as “geoengineering” — is intended to be carried out for the good of humankind.

Or so the argument goes.

Playing god for all the right reasons

In late 1958, Harry Wexler, then-director of meteorological research at the U.S. Weather Bureau, described a means of “modifying the weather on a large scale.” The proposal, published in the journal Science, discussed a method of producing a massive amount of steam in the Arctic Ocean. This, he suggested, would condense to form a cloud of ice covering the region with the goal of reducing “by half the loss of heat by radiation from the Earth’s surface around the Pole.” Doing so would have major, climate-altering effects on our planet as we know it. How might this hypothetical massive cloud of steam be achieved? Simple: by detonating ten 10-megaton bombs in the ocean during winter.

Geoengineering is risky and unproven, but soon it might be necessaryA 1958 feature on weather control from the South Illinoisan featuring Dr. Harry Wexler. Newspapers.com

Needless to say, Wexler’s proposal wasn’t taken up. But 60 years later the idea behind it — that humankind has the power and, perhaps, the moral imperative to alter our climate for global good — continues to entice scientists and other researchers.

The difference between 1958 and today is that, here in 2019, we know far more about the effects of climate change. Concerns which were just beginning to be raised in the late 1950s, such as Charles David Keeling’s discovery that the level of carbon-dioxide in the atmosphere was rising, are today widely understood. In many parts of the world, the effects of climate change are, unfortunately, all too evident to see through extreme weather events.

It’s conceivable that what we’re seeing in the extremely welcome expansion of solar and wind are, to some extent, low-hanging fruit.

Reducing the levels of carbon-dioxide and other greenhouse gases in the atmosphere is a problem that takes on increasing urgency as time goes by. Even if we don’t actively increase the amount of carbon-dioxide being pumped out per person, the world’s growing population means the problem will get exponentially worse if we just stay our current course.

n 1800, the world’s population stood at an estimated 1 billion people. By 1900, that figure had risen to 1.6 billion. Today, it is somewhere north of 7 billion. By 2100, projections suggest that it could hit 10 billion. Levels of carbon-dioxide must therefore be lowered, per capita, simply for us to stay at the same unsustainable level we are at currently.

Remaking the planet

One of the best books written about geoengineering is Oliver Morton’s The Planet Remade. It begins with Morton asking us the two questions that have led many to consider this as one of the only viable solutions to climate change.

Firstly, Morton questions, do we believe that the risks of climate change merit serious action intended to lessen them? Secondly, do we believe that reducing an economy’s carbon-dioxide emissions to near zero is very difficult indeed using our current methods? Answering “yes” to both of these questions is what leads to a more drastic form of climate action. Enter geoengineering.

Geoengineering is risky and unproven, but soon it might be necessary Ed Ritger/Climate One

“The reason I think the world needs to better understand geoengineering is because even the most optimistic projections about decarbonization do not show show decarbonization that will keep the world in the [3.6 degrees Fahrenheit] boundaries proposed by the Paris Agreement,” Morton told Digital Trends. “It’s also not clear that the policies which may drive the industrial economies of the world down the first half of the carbon-cutting curve will work for the second half. It may be possible to reduce our electricity use, but there are plenty of other places it may be much harder to reduce carbon. It’s conceivable that what we’re seeing in the extremely welcome expansion of solar and wind are, to some extent, low-hanging fruit. It’s easier to decarbonize an electricity grid than, say, steelworks or cement works.”

Different approaches to geoengineering

Changing the complex system that is our planet sounds difficult. That much is clear. However, the good news — if melting ice-caps and increasing numbers of freak weather events can ever be considered “good” — is that we know it can be done. We’ve done it before. The industrialization which led to our current level of climate change was a form of geoengineering, albeit an unintentional one.

There is a prevailing concern that efforts such as solar geoengineering would prove prohibitively expensive. This is untrue.

Fortunately, today’s geoengineering proposals aren’t quite as apocalyptic as Harry Wexler’s meteorological bombing campaign. Broadly speaking, they fall into one of two camps. The first is what is known as Solar Radiation Management (SRM) or solar geoengineering. The idea here is to reflect some of the Sun’s energy back into space, thereby offsetting the temperature rise caused by the increased levels of greenhouse gases in the atmosphere.

Two of the leading suggestions for carrying out solar geoengineering involve space reflectors for blocking some sunlight before it reaches Earth, or using stratospheric aerosols containing small, reflective particles to bounce sunlight from the upper atmosphere.

In the other corner is what is termed Greenhouse Gas Removal (GGR) or carbon geoengineering. This seeks to remove carbon-dioxide and other greenhouse gases from the atmosphere by sucking it out of the air. This could be achieved (among other potential methods) through massive tree-planting efforts, adding nutrients to the ocean to draw carbon-dioxide from the atmosphere, or building large machines which remove carbon-dioxide from ambient air and store it.

Geoengineering is risky and unproven, but soon it might be necessaryVarious solar and carbon geoengineering proposals designed to increase solar reflectance or capture and store carbon. Encyclopædia Britannica, Inc

At present, there has been much more focus on carbon geoengineering, both in terms of lawmaking and funding. Recently, for example, the Canadian company Carbon Engineering closed a $68 million equity financing round for its technology designed to capture carbon in the atmosphere.

Solar geoengineering, while extremely promising in its own right, has not been afforded the same opportunities. This is, likely, partly due to the massive scale of such projects. But addressing climate change in a meaningful capacity could well involve a combination of these two approaches working together.

Should we worry?

As with any major paradigm-changing development, there are big concerns about geoengineering. Interestingly, Morton suggests that worries about large scale efforts to battle the effects of climate change have actually worsened as our knowledge of climate change has increased.

“People have significant worries about the whole idea … [of] an organization that might ‘play god’ with the climate.”

“You might think of that as counterintuitive,” he said. “You’d imagine that as people became aware of the effects of inadvertent climate change, they’d be looking for ways to offset it. But I think it’s absolutely understandable and intuitive. As people become more worried about what humans are doing to the climate, there’s less of an appetite for deliberately doing that. That’s because so much of the discourse about climate is about uncertainty and unintended consequences.”

Some of the issues raised around geoengineering are most likely misconceptions, such as the belief that solar geoengineering efforts would have to continue indefinitely. They would not. Others have worried that efforts such as solar geoengineering would prove prohibitively expensive. This is also untrue. A Harvard study recently concluded that spreading particles in stratosphere to fight climate change may cost just $2 billion per year out of the $500 billion currently spent on green energy initiatives.

But still other concerns are valid — and worthy of more exploration. For example, a 2018 paper published in the journal Nature suggested that reflecting the sun’s rays back into space could cause widespread crop failure. This would cancel out any benefits to farming from the reduction in warming.

Researchers have also raised concerns that geoengineering could have devastating impacts by altering rainfall and storm patterns in some parts of the world; caused by cooling the planet while simultaneously keeping massively elevated levels of carbon-dioxide in the atmosphere.

Do we have time to waste?

In many of these cases, the jury is still out. One recent study in Nature Climate Change countered some potential issues.

“Our study evaluated the climate response to a scenario where solar geoengineering halved the warming from a doubling of CO2 concentrations,” Peter Irvine, a postdoctoral fellow at Harvard’s John A. Paulson School of Engineering and Applied Sciences, told Digital Trends. “We found that halving warming roughly halved overall climate change in all variables we looked at and offset over 80 percent of the increase in tropical cyclone intensity simulated in our global warming scenario. We also tested whether this held at the local scale or whether in some places solar geoengineering increased the magnitude of climate change. We found that less than 0.5 percent of places saw greater change in water availability or extreme precipitation in our solar geoengineering scenario than they would have seen without solar geoengineering.”

Ultimately, geoengineering is still a developing science. Questions need to be asked about the bold solutions posed, but the biggest question is just how much time we have left to enact these changes. There are certainly risks associated with any effort to change the climate. But they may also turn out to be necessary risks.

“People have significant worries about the whole idea that there might be an organization that might ‘play god’ with the climate,” Morton said. “I absolutely share that concern. But I have to balance it with concerns about the fact that the climate is being altered without anyone ‘playing god’ in this way.”

To check out the rest of Troubleshooting Earth, head over to the series homepage.

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