At the world’s first major geoengineering conference, two separate scientists put forward proposals to use lasers to modify the Earth’s climate and fight global warming, from space.
One suggested that a satellite equipped with a high-powered laser could grow clouds in the atmosphere below; the other proposed lasers that would blast greenhouse gases from orbit to effectively erase the agents of climate change.
The highly theoretical proposals are still in their early stages, and easily count as the more radically ambitious of the already radically ambitious climate engineering schemes discussed by scientists. These plans don’t concern gadgets that absorb carbon pollution or spreading particles in the sky, after all—we’re talking about space lasers powerful enough to alter the climate.
And European Space Agency fellow Isabelle Dicaire studies them full time. She traveled to Berlin this week to discuss how a satellite equipped with high-powered LIDAR lasers may prove useful for researching—and maybe eventually actually orchestrating—climate engineering.
LIDAR is remote sensing technology that blasts a laser at a target, then analyzes its reflection to accurately measure distances. It’s already widely used here on Earth (on things such as Google’s driverless car), and by NASA’s CALIPSO satellite. Dicaire is interested in what we could do with a much more powerful LIDAR positioned in space; theoretically, it should be able to better detect the movement of particles in clouds, and maybe even make new ones.
this would be the first step if you’d like to do laser cloud seeding
Among the most widely discussed geoengineering ideas of recent years is so-called cloud-brightening. A cloud is just a mass of water vapor that’s condensed into droplets around particles floating in the air—and the more droplets in a cloud, the more sunlight gets bounced off of them.
So, geoengineers figure that if you can increase the surface area of clouds, or seed more of them altogether, you could begin to reflect back enough sunlight to cool the globe. Research into the subject has been limited, and Dicaire says a powerful LIDAR would help scientists better understand the science. Beyond that, it could be used to carry out the cloud-seeding itself.
“Another application is to use the effects that are happening inside the plasma filaments to do some exotic stuff. For instance, laser-based cloud seeding,” she said. Researchers at the University of Geneva, Dicaire says, have demonstrated that lasers can produce droplets.
“They are generating nano-sized water droplets from the laser,” she said. They’re doing it in a lab, though. “I’m monitoring the field to see what we could do from space.”
So, theoretically: “You can use the Earth Observation System to target or find where you have your clouds, what kind of clouds you would like to seed, and then from that, aim the beam towards these clouds.” Bear in mind that the idea ESA is examining here is entirely theoretical, and no laser even exists in orbit capable of performing such a feat. But it’s not unthinkable, technologically speaking—the political and economic hurdles are probably larger.
“So far you can only find these laser sources on the ground. Eventually, if someone would like to put them in a satellite, they would have to space qualify them. So this is something that some industries are looking into. And this would be the first step if you’d like to do laser cloud seeding.”
This would likely be a pretty expensive way to make clouds brighter—older proposals suggest using boats to spray seawater skyward—and you’d need an awful lot of cloud-growing laser satellites. But Dicaire, for now, is more interested in the underlying research LIDAR could help scientists perform.
“It’s a very basic concept. The only one looking at it at the moment is ESA, and it’s very preliminary. We just want to see if it’s possible to send your beam from the satellite to the ground. If it’s possible then, yeah, we’ll look more closely into this,” she said.
Alternatively, we could use another type of laser-toting satellite to blast away the greenhouse gases already in the atmosphere. That’s what Aidan Cowley, a professor at Dublin City University, proposes, anyhow. He believes that a solar-powered satellite equipped with a plasma laser could hone in on heat-trapping gases in order to get them to break apart into less harmful ones.
“We’ve already observed here on earth that plasma ionization approaches, for example, air plasmas, can essentially dissociate long-lived pollutants: SF6, carbon dioxide. This is something we’ve observed, and it’s been well reported in literature,” Cowley told me. “Plasma essentially will excite whatever gas it’s traveling through, and just by giving energy to these gases, these molecular species, they’ll break up—in the case of SF6, they’ll become S, and become more benign greenhouse gases.”
It’s an alluring idea, of course; SF6 is a potent and long-lasting greenhouse gas. And our immense CO2 output is driving climate change toward a cliff; it’d be convenient if we could just zap them away with a laser. So why haven’t we done it already, if plasma ionization has proven to scatter the building blocks of our climate crisis?
“The problem about using [lasers] as a means of actually addressing climate, greenhouse gases per se, is that the energy used to strike those plasmas has to be generated here on Earth. So essentially you’re burning fuel to destroy the emissions that you’re producing anyway, and it ends up being a net positive to the emissions profile anyway. So you have to come up with a low cost, energy-free scenario that frees you from that paradigm. And that’s where the idea of using space solar power to do so comes into it.”
A satellite outfitted with high-efficiency solar panels should do the trick.
there’s nothing crazy about it, solar power in space
“Essentially by using abundant power that’s available in orbit, to drive ionization phenomenon in the atmosphere, you can neatly size up the problem of doing the same thing here on the ground, and you have a nearly unlimited supply of energy to do so. You just need to develop the technology and tap it for that,” he said.
Now, there are other pitfalls here; those greenhouse gases are already pretty diffuse in the atmosphere, so it’d be hard to target them effectively with a laser. Cowley says you’d probably need multiple units to do it effectively. Then there’s the vast expense of building, testing, and deploying the machines, of course.
Cowley also says his satellite would be useful for creating ozone, to patch up the holes we’ve left by overusing aerosols. “You could use it to create ozone, too,” he said. “Pretty strong pedigree for producing ozone. It’s a very easy trick.” Then again, he adds, the technology could be used to the reverse effect, too.
“Conversely, from a military perspective, you could also use it to destroy the ozone as well, if you do it the right way,” he said. “It could potentially open the holes in the atmosphere of your not too friendly neighbors.”
So does Dr. Cowley think his greenhouse gas-blasting satellite is feasible?
“I still think it will take a long time. It’s got an underground movement to a certain degree, so I think it will continue to be developed, going forward. Space solar power has got a fairly good future for certain applications, and, I think, eventually, like most technology, it will be the niche that drives the mainstream adaptation,” he said. “Find one good niche and make it work, and people will go, ‘oh that’s not so crazy after all.’ And there’s nothing crazy about it, solar power in space. It’s not science fiction.”
Scientists Propose First Major Framework for Climate Engineering Experiments
August 18, 2014 // 02:15 PM EST
Professor Steve Rayner, the co-director of the Oxford Geoengineering Programme, has unveiled a proposal to create the first serious framework for future geoengineering experiments.
It’s a sign that what are still considered drastic and risky measures to combat climate change, like artificially injecting tiny particles into the Earth’s atmosphere to reflect sunlight back into space, are drifting further into the purview of mainstream science. The august scientific body has issued a call to create “an open and transparent review process that ensures such experiments have the necessary social license to operate.”
Rayner, who served on the Royal Society of London’s Working Group on Climate Geoengineering, released what’s been christened the ‘Berlin Declaration’, at the world’s first major climate engineering conference currently underway in Germany. Rayner issued a call for amendments from the conference’s attendees, which includes top climate scientists, policymakers, and geoengineering scholars.
The draft, in its current iteration, states that “New technologies have the potential to provide significant benefits to society, but they can also be controversial. Indeed the controversies surrounding new technologies have often led to a backlash against their development, as has been seen in the fields of genetically modified organisms and nuclear power.” You can read the full draft here—it was distributed at the Climate Engineering Conference in Berlin, where I’ll be reporting from all week.
It’s specifically focused on a subset of geoengineering projects called solar radiation management, which also includes proposals to brighten clouds over the ocean and to send tiny mirrors into orbit to deflect sunlight. The grander geoengineering projects, which fall into this category, have inspired comparisons to schemes befitting Dr. Evil.
“The emergence of interest in climate geoengineering, broadly defined as the deliberate large-scale manipulation of the planetary environment to counteract climate change, has provoked controversy about the practicality and wisdom of such ideas,” the document reads.
In an interview, Rayner told me that the document was inspired in part by a failure of a previous foray into climate engineering experimentation, the first attempt by the SPICE (Stratospheric Particle Injection for Climate Engineering) project to explore aerosol delivery into the stratosphere.
That undertaking would have floated a blimp a kilometer into the sky to spray 40 gallons of water into the atmosphere, in an attempt to illustrate the machinery that could be used to deliver aerosol particles into the stratosphere.
The impact of the experiment would have been negligible on the climate, but, according to Rayner and the Guardian, it caused a public backlash, and was eventually cancelled for unrelated reasons. Rayner says scientists interested in studying geoengineering need to learn from the debacle, and to make sure future experiments are carefully and responsibly vetted, both scientifically and publicly.
“We need to be very careful in these initial steps,” he told me, in order to create “a pragmatic pathway” to climate engineering experiments. He notes that the vast majority of the geoengineering experiments currently under consideration are so small in scale they “couldn’t conceivably have any effect on the atmosphere,” but that scientists need to consider the “social and political consequences.” He said that he and his colleagues did harbor concerns that they were making things “thinkable that ought to be unthinkable” but that with or without a framework, scientists were going to experiment with climate engineering, and it was best to do so in a measured way that kept the public informed.
Dr. Ken Caldeira, a prominent American atmospheric scientist also attending the conference, worries that such a document will ultimately prove stifling to climate science. It’s too broadly defined, he says, and could end up preventing research that’s only tangentially related to geoengineering, if future regulators object to it.
“There’s a real possibility that this governance, or regulations, could hurt climate science,” he said. Regulators could, for instance, not consider carbon sequestration (the act of pumping pollution underground) to be geoengineering, but decide that painting roofs white (another, less controversial geoengineering proposal) is.
“How do you define ‘experimental work on such techniques’?” Caldeira told me, referring to a line in the text that appears to be vague. “I think it will end up doing more harm than good.”
The proposal has already caused heated debate amongst the scientists and commentators in Berlin, and whether it is accepted and published remains to be seen. But Rayner believes that, at least as a subject for discussion and experimentation, geoengineering is here to stay.
“A decade ago, ‘nanotechnology’ was a word that was on everybody’s lips,” he said in a panel discussion. Now we mostly talk about the specific applications of nanotech, because it’s become so commonplace. Rayner believes the same will happen with geoengineering—it will become normalized. “My prediction is that the word ‘geoengineering’ will fall out of use, and be replaced by discussion of more specific technologies.”
Update: This article formerly stated that the Royal Society of London was behind the proposal; it is fact written by an affiliated scientist, but has not yet formally been endorsed or recognized by the organization. Motherboard regrets the error.