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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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The Ethics of Geoengineering: An Interview
With Oliver Morton
by Christopher Cokinos
What if we could fashion a planetary umbrella out of sulfur? What if there
were techno-fixes to climate change? Who would decide to deploy them?
What would the rest of us have to say?
An editor at The Economist in London, Oliver Morton has established a
reputation as an essential science writer with such books as Mapping Mars:
Science, Imagination and the Birth of a World and Eating the Sun: How Plants
Power the Planet. His latest is The Planet Remade: How Geoengineering Could
Change the World, a thoughtfully written and meticulously reported volume
that explores the nascent and controversial field of deliberate technological
interventions in the climate — interventions meant to cool the planet.
Once unmentionable among scientists and policymakers as an approach to
global warming, geoengineering has recently come to the fore as an option
— or a last resort. The failure to actually reduce global emissions has meant
that all possibilities are now on the table, including some that sound like
premises from a science-fiction novel: Humans could sequester carbon
dioxide by removing it from the air through technologies that mimic trees,
or we could spray water droplets in the lower atmosphere to reflect light and
heat back to space, or we could seed sulfur aerosols in the stratosphere to do
the same. We know the latter option has worked because that’s what really
big volcanoes do. The first approach is called, simply, CDR, or carbondioxide removal; the second two are forms of SRM, or solar-radiation
management.
Since the field is mired in controversy, very little real-world geoengineering
has taken place. Research has been essentially confined to computer models,
while debate continues between those who advocate the need to test this
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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approach and those who see geoengineering as a way to avoid actually
reducing greenhouse-gas consumption. Questions of how geoengineering
should be regulated are paramount, as are possible regional side effects,
which could include increased drought in some areas.
Morton blends careful research, beautiful writing, and dramatic storytelling
skills with a meditative tone, inviting readers to consider not only the literal
possibilities of geoengineering but the wider historical truth that we already
have deeply altered a variety of crucial planetary processes. Seen in this
light, geoengineering becomes less of a “techno fix” and more of an
existential question: Can humanity use its power to save ourselves — and the
rest of the biosphere as it now stands?
Even exploring such an approach is a non-starter for many mainstream
environmentalists and those suspicious of technology and capitalism’s ability
to serve socially just ends. But geoengineering remains a part of the future
for some upstart ecological modernists, who argue that intensifying
efficiencies and embracing some technologies (including genetically
modified organisms) can lift people out of poverty while also leaving more
wild nature alone. Like the eco-modernists, Morton shares an interest in
technological approaches to environmental problems. Unlike some, he is
perhaps more sanguine about the questions of social governance.
Morton’s is a balanced and deeply considered book that forces readers to
confront not only basic assumptions about the human relationship to the
non-human world but to consider what we must do if that relationship is to
move from recklessness to stewardship on a planetary scale. The Planet
Remade is, yes, a deliberate and important book, and I spoke with Morton
one recent morning to talk about it.
The subtitle of your book The Planet Remade is How Geoengineering
Could Change the World. It’s not “will” or “should.” Can you talk about
geoengineering’s prospects in the coming decades? Do you expect to
see geoengineering happen in your lifetime?
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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Well, first I’d like to slightly expand your time horizon looking backwards.
The progress of geoengineering has been from a mainstream, if not
practically intended, area of scientific speculation to something not talked
about, and now it is swinging back. I say this to emphasize that ideas about
how people might and should interact with the climate have been quite
labile over the decades and centuries, and I think that that is the right sort
of timescale for this sort of discussion.
What I hope to see happen in my lifetime, which we’ll be actuarial about
and top out somewhere in the early 2040s, is that there is a serious
discussion about realizing geoengineering in some sort of safe, just, and
governable form as an additional response to climate change. If it can’t be
made safe, just, and governable to any satisfactory degree (all those
adjectives have gradations) then I don’t want to see it.
This maybe goes right to something you bring up near the end of the
book: “There is a word mostly missing from this book. It is ‘we.’” In a
first-world culture with a spotty technological track record, political
dysfunction, and scientific illiteracy — can we have a serious discussion
about geoengineering that could result in a safe, just, and governable
deployment? I mean, what does that look like, to have the discussion
first?
Well, I don’t want that discussion to happen just in the culture that you
describe; this is a global issue, and the discussion needs to reflect that
(though that in no way makes things easier). To a significant extent this
would mean a broadening out of the current discussion about climate. You
might note that that discussion is a poor one, perhaps particularly in the
United States, but it is real and it engages the world. Part of the broadening
I would imagine would be to increase the role played in that discussion by
the reduction of harm (and the risks of harm).
A greater focus on reduction of actual harm makes it easier to look at other
responses — most notably adaptation, but also perhaps geoengineering. This
is a view that I think fits well, by the way, with making sure that the debate
is global; the parts of the world where most people live, where most
emissions are, and where most harm is likely to be felt may well be strong
participants in that sort of re-shaping.
So ideally the discussion about geoengineering is really in that wider
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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frame and takes place in the media, classrooms, legislative bodies, and
the like? I just wonder if we are facing timescales that are too pressing
for what might be a slow cultural discussion.
I think you may be overdoing the slow change aspect of things. Some things
are hard and thus slow to change — a world-spanning industrial economy
based on more than 80 percent fossil-fuel energy and its associated
distribution and conversion technologies is one of them.
Attitudes to nature may move rather quicker. Deep as they feel to us, they
may display less inertia. To take an example: When my colleagues at The
Economist began to champion gay marriage about 20 years ago, the case
against seemed both to be very entrenched and to lean very heavily on
notions of what was and wasn’t “natural.” And though those beliefs are still
there in many people, they have proved to be quite changeable in many
others.
I have heard friends and colleagues suggest that this means that getting rid
of fossil fuels might be similarly quick and comparatively easy (though I
don’t want to under emphasize the hard work the gay-marriage cause has
required). I think that parallel is misleading, because of the costs and
interests involved in eliminating fossil fuels, but the parallel to a change of
heart about “nature” that might see a broader interest in geoengineering
strikes me as at least a bit plausible.
Indeed, in the community of scientists and scholars and wonks that thinks
about geoengineering, there is a persistent worry that some changes in
mindset might come terribly quickly: Specifically, they fear that a significant
part of the political class, especially in America, might move with
Necker-cube instaneity from “climate change does not exist/is not man made
and thus is not a problem to address” to “climate change can be easily sorted
out by geoengineering and is not a problem to address any further.”
And that’s a worry because to those people — as to me — it embodies two of
the great mistakes in thinking about geoengineering. One is that once you
have decided on the technology, that’s it — no more work on “safe, just, and
governable.” The other is that it treats geoengineering as a categorical
alternative to other forms of climate action, when it [geoengineering] is
better seen as an adjunct. To champion geoengineering as a way of simply
avoiding the difficulty of fundamentally changing the world’s energy system
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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is, to me and most others who think about it, really wrong. If
geoengineering is to make sense, it must be in concert with action on
mitigation and adaptation.
But to return to your point on unilateral action. I don’t take pure
Greenfinger scenarios — tech billionaire starts to put aerosols into the sky
with his own devices — all that seriously, because I think the response would
be quite swift and strong. I do think, though, and I explore in the book, the
possibility of action by a small group of states. People tend to think that a
state that might do this would have to be a very strong one, a nuclear
weapon state, perhaps. But I think there is also, to borrow from Vaclav
Havel, a “power of the powerless.”
States that are not major emitters and are seeing serious harm, even
existential loss, might choose to act in such a way as to confront the broader
world with facts on the ground: “This is here, how are you going to
proceed?” That short-circuits some governance talk. The idea of perfect
governance in advance is not necessarily attainable. I think that’s the lesson
of history. But that in no way means that states and other actors should not
think about and develop mechanisms for governance that might be called
into action rather quickly should circumstances warrant.
One last question. Critics see geoengineering as a techno-fix, sort of
like the attitude you described just now: “Oh, climate change is here,
after all, but we don’t have to do anything so long as we can
geoengineer.” But you have a lovely passage in the book about the
necessity of utopian thinking or, to take it down a notch, perhaps just
the human impulse to craft lasting beauty. Can you briefly talk about
that?
Well, the technological fix attitude stems from a belief that the problem is
simply posed in a language that technology can address. I tend to see
climate change as much too complex a set of issues for that sort of attitude
to be defensible. I see it as part of the context in which everything else plays
out — something you respond to and worry about rather than try to take off
the table with a simple solution or with some mechanism of control like
those which so dominated a lot of thinking in the application of science in
the 20th century. Because, geoengineered or not, the fact that human
influence now reaches deep into the planet’s workings at nearly all scales
and in many ways is here to stay, and that needs to be worked with.
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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I suppose that’s where I differ somewhat from the eco-modernists. They
have a tendency to see the correct response to the current situation as to
power through it by having higher density energy sources — notably small,
safe nuclear plants — and more intense farming and thus providing more
space for nature. It’s a coherent and interesting program, and one that I
think offers much to like, such as an emphasis on energy access for the poor
of the world. But it also seems to me to rely on an old-fashioned division of
the human from the natural, with the natural providing some sort of
external “other” that humans, once modernized, can be relied on to value.
My sense of nature is less about it as a thing, or set of things — a place, an
untouched ecosystem, an unveiled sky — but as process that is ungoverned,
or self-willed, in a way that provides tensions and resolutions to our lives.
Earlier on I mentioned a contrast between climate action as harm reduction
and climate action as restoration, and positioned myself rather more in the
former camp than in the latter one. But the two are not mutually exclusive.
One of my guiding thoughts when writing The Planet Remade was a line
from my friend Francis Spufford’s remarkable book about the emotional
basis of a contemporary Christian life and calling, Unapologetic: “Far more
can be mended than you know.”
I am not a Christian, though I was raised as one, but that line speaks to me
strongly in my own damaged way and resonates with images of things
beautifully mended. It puts me in mind of a sermon that my uncle, Martin
Loft, preached at my sister’s wedding when I was a child and which stayed
with me, about how wedding rings are gold because the gold does not
tarnish but is also soft, and thus takes nicks and tiny dents that build up into
a patina richer than a perfect gloss.
I would never wish harm simply so that it might be relieved. I don’t want to
aestheticize or spiritualize climate action to an undue extent. But it’s foolish
to think that aesthetics and matters of the spirit and emotional temperament
don’t shape the way one confronts and responds to these issues. And I like
the beauty, and morality, of a work in progress, a successive approximation
to the good, one that calls on us to keep trying and rewards us for those
efforts by the sense of being part of something.
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The Ethics of Geoengineering: An Interview With Oliver Morton —...
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Catastrophic Consequences of Climate Change is Pacific Standard’s year-long
investigation into the devastating effects of climate change — and how scholars,
legislators, and citizen-activists can help stave off its most dire consequences.
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Meet the Man with a Cheap and Easy Plan to Stop Global War...
http://www.technologyreview.com/featuredstory/511016/a-chea...
A Cheap and Easy Plan to Stop Global
Warming
Intentionally engineering Earth’s atmosphere to offset rising
temperatures could be far more doable than you imagine, says David
Keith. But is it a good idea?
By David Rotman on February 8, 2013
313 COMMENTS
Here is the plan. Customize several Gulfstream business jets with military engines and with equipment to
produce and disperse fine droplets of sulfuric acid. Fly the jets up around 20 kilometers—significantly
higher than the cruising altitude for a commercial jetliner but still well within their range. At that altitude
in the tropics, the aircraft are in the lower stratosphere. The planes spray the sulfuric acid, carefully
controlling the rate of its release. The sulfur combines with water vapor to form sulfate aerosols, fine
particles less than a micrometer in diameter. These get swept upward by natural wind patterns and are
dispersed over the globe, including the poles. Once spread across the stratosphere, the aerosols will
reflect about 1 percent of the sunlight hitting Earth back into space. Increasing what scientists call the
planet’s albedo, or reflective power, will partially offset the warming effects caused by rising levels of
greenhouse gases.
The author of this so-called geoengineering scheme, David Keith, doesn’t want to implement it anytime
soon, if ever. Much more research is needed to determine whether injecting sulfur into the stratosphere
would have dangerous consequences such as disrupting precipitation patterns or further eating away
the ozone layer that protects us from damaging ultraviolet radiation. Even thornier, in some ways, are the
ethical and governance issues that surround geoengineering—questions about who should be allowed
to do what and when. Still, Keith, a professor of applied physics at Harvard University and a leading
expert on energy technology, has done enough analysis to suspect it could be a cheap and easy way to
head off some of the worst effects of climate change.
According to Keith’s calculations, if operations were begun in 2020, it would take 25,000 metric tons of
sulfuric acid to cut global warming in half after one year. Once under way, the injection of sulfuric acid
would proceed continuously. By 2040, 11 or so jets delivering roughly 250,000 metric tons of it each
year, at an annual cost of $700 million, would be required to compensate for the increased warming
caused by rising levels of carbon dioxide. By 2070, he estimates, the program would need to be injecting
a bit more than a million tons per year using a fleet of a hundred aircraft.
One of the startling things about Keith’s proposal is just how little sulfur would be required. A few grams
of it in the stratosphere will offset the warming caused by a ton of carbon dioxide, according to his
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estimate. And even the amount that would be needed by 2070 is dwarfed by the roughly 50 million
metric tons of sulfur emitted by the burning of fossil fuels every year. Most of that pollution stays in the
lower
atmosphere,
and the
molecules
are washed
of days. In contrast, sulfate
Meet the
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particles remain in the stratosphere for a few years, making them more effective at reflecting sunlight.
The idea of using sulfate aerosols to offset climate warming is not new. Crude versions of the concept
have been around at least since a Russian climate scientist named Mikhail Budkyo proposed the idea in
the mid-1970s, and more refined descriptions of how it might work have been discussed for decades.
These days the idea of using sulfur particles to counteract warming—often known as solar radiation
management, or SRM—is the subject of hundreds of papers in academic journals by scientists who use
computer models to try to predict its consequences.
But Keith, who has published on geoengineering since the early 1990s, has emerged as a leading figure
in the field because of his aggressive public advocacy for more research on the technology—and his
willingness to talk unflinchingly about how it might work. Add to that his impeccable academic
credentials—last year Harvard lured him away from the University of Calgary with a joint appointment in
the school of engineering and the Kennedy School of Government—and Keith is one of the world’s most
influential voices on solar geoengineering. He is one of the few who have done detailed engineering
studies and logistical calculations on just how SRM might be carried out. And if he and his collaborator
James Anderson, a prominent atmospheric chemist at Harvard, gain public funding, they plan to conduct
some of the first field experiments to assess the risks of the technique.
Leaning forward from the edge of his chair in a small, sparse Harvard office on an unusually warm day
this winter, he explains his urgency. Whether or not greenhouse-gas emissions are cut sharply—and
there is little evidence that such reductions are coming—”there is a realistic chance that [solar
geoengineering] technologies could actually reduce climate risk significantly, and we would be negligent
if we didn’t look at that,” he says. “I’m not saying it will work, and I’m not saying we should do it.” But “it
would be reckless not to begin serious research on it,” he adds. “The sooner we find out whether it
works or not, the better.”
The overriding reason why Keith and other scientists are exploring solar geoengineering is simple and
well documented, though often overlooked: the warming caused by atmospheric carbon dioxide buildup
is for all practical purposes irreversible, because the climate change is directly related to the total
cumulative emissions. Even if we halt carbon dioxide emissions entirely, the elevated concentrations of
the gas in the atmosphere will persist for decades. And according to recent studies, the warming itself
will continue largely unabated for at least 1,000 years. If we find in, say, 2030 or 2040 that climate
change has become intolerable, cutting emissions alone won’t solve the problem.
“That’s the key insight,” says Keith. While he strongly supports cutting carbon dioxide emissions as
rapidly as possible, he says that if the climate “dice” roll against us, that won’t be enough: “The only thing
that we think might actually help [reverse the warming] in our lifetime is in fact geoengineering.”
The Experiment
David Keith clearly sees the world through the eyes of an experimental physicist. During his time as a
graduate student in the MIT lab of David Pritchard, he spearheaded a project that built the first atom
interferometer. Keith and his coworkers outcompeted some of the world’s top atomic-physics labs,
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including
one at Stanford led by Steven Chu, who later won a Nobel Prize and served as the U.S.
secretary of energy. Everyone knew the interferometer would be a breakthrough, recalls Pritchard, but
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Keith
displayed
combination
and
the ability to “blast
ahead” through the frustrations
Meet the
Man withaarare
Cheap
and Easy Planoftocreativity
Stop Global
War...
http://www.technologyreview.com/featuredstory/511016/a-chea...
and difficulties of building and testing it. Keith, however, says his remarkable achievement caused him to
“walk away from [atomic] physics,” in part because one of the most obvious applications for atom
interferometry was in highly accurate gyroscopes for submarines carrying ballistic missiles.
Soon, Keith had moved on from the esoteric world of atomic physics to energy problems. In 1992, he
published a paper called “A Serious Look at Geoengineering,” one of the first rigorous scientific reviews
of the topic. Almost no one cared.
Indeed, the field of geoengineering remained more or less dormant for much of the next decade. A
handful of serious scientists wrote occasional papers and the field attracted a robust fringe of fanatics,
but academic discussion of the subject—let alone actual research—remained somewhat taboo. Many
felt that discussing geoengineering as a realistic option would take attention away from the urgency of
cutting greenhouse-gas emissions. Then, in 2006, Paul Crutzen, one of the world’s leading climate
scientists and a winner of the 1995 Nobel Prize in chemistry for his work on atmospheric ozone
depletion, published a paper called “Albedo Enhancement by Stratospheric Sulfur Injections: A
Contribution to Resolve a Policy Dilemma?”
In the paper, Crutzen acknowledged that the “preferred way” to address climate warming was to lower
emissions of greenhouse gases, but he concluded that making sufficient cuts was only “a pious wish.”
Not only did he give his blessing to the idea of geoengineering, but he singled out the use of sulfate
aerosols in particular as worthy of research, even though it’s well known that the particles can facilitate
the chemical reactions that lead to ozone loss. He pointed to the eruption of Mount Pinatubo on an
island in the Philippines in 1991 as evidence that sulfate particles can effectively cool the planet. The
giant volcano spewed some 10 million metric tons of sulfur into the stratosphere. Subsequent analysis
showed that the world’s temperature decreased by an average of 0.5 °C for a couple of years.
At a time when many experts were increasingly frustrated with the lack of progress in cutting
greenhouse gases, the paper permitted the topic of intentional climate alteration to be more openly
discussed. In subsequent years, geoengineering gained still more attention, including high-profile
reviews by the U.K.’s Royal Society and the Washington-based Bipartisan Policy Center, both of which
recommended further exploring SRM. (Keith helped write both reports.) Endless modeling and computer
simulations have followed. But now Keith is anxious to conduct field experiments.
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That idea is highly controversial. Many climate scientists still consider field experimentation premature,
and critics of geoengineering tend to believe it would be the first step in what would turn into an
inexorable move toward full-scale deployment. Last year, a public outcry led by several international
environmental groups helped shut down a simple experiment that a team of British researchers had
proposed. The group wanted to pump water to a height of one kilometer through a thin hose held aloft
by a helium balloon. The object would have been to test whether a similar system could someday be
used to inject sulfur particles into the stratosphere at an altitude of 20 kilometers.
The experiments Keith and Anderson are considering would be far more ambitious. Their goals: first, to
test how sulfuric acid should be distributed to optimize the size and longevity of the resulting particles,
and second, to measure how sulfur affects ozone at the altitude and under the conditions associated
with SRM.
Anderson, who helped unravel the chemistry behind the ozone hole that appeared in the Antarctic
during the 1980s, says the “demonic system” that implicates sulfate particles in ozone destruction is
highly sensitive to the levels of water vapor in the air. So in one set of experiments, using a scheme
based on Anderson’s earlier work, the group would send a helium-filled balloon to the lower
stratosphere, use a Kevlar thread to lower canisters filled with water vapor and sulfur, and release small
amounts of the test samples. Then the researchers would drop down miniature laser-based analytic
instruments to monitor the chemistry in the small “seeded” area. The setup, says Anderson, provides
“exquisite control” and a way to precisely monitor the effect of different amounts of sulfur and water
vapor.
Anderson stresses that the experiment would have no conceivable impact on the stratosphere: it would
use only “micro-amounts” of sulfur and would be confined to a very small region. And he says it is critical
to study the reactions under the conditions “where they actually take place” and not in the confines of
the
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“tremendously” because of the potential impact on ozone. He points to a study his group published last
year in Science showing that increasingly intense summer storms over the United States—triggered by
climate warming—are injecting more water vapor into the stratosphere. That, he says, could speed the
ozone-destroying reactions: “If nature is adding increased water vapor to the stratosphere and we’re
adding sulfates, it is a very lethal cocktail for ozone loss.”
Keith appears more sanguine. “The uncertainties are substantial,” he says. “You could get very bad
[ozone] outcomes, but there are also ways where you could have no impact, or even a positive impact,
on ozone.” In any case, he says, it is “just crazy” not to begin conducting experiments on solar
geoengineering to find out. Nearly all the work done on SRM is based on computer modeling, and Keith
says we need to move to “perturbation experiments” to learn whether we can use it to safely and
effectively intervene in the climate. The field “really needs to grow up” and begin experiments in “the real
world,” he says.
Barking Mad
Critics of SRM—and even its advocates—note that the technology has numerous limitations, and that no
one is entirely sure what the consequences would be. Sulfate aerosols reflect sunlight in the upper
atmosphere, thus directly cooling the planet. But greenhouse gases operate very differently, trapping
long-wave infrared radiation escaping from Earth’s surface and thus warming it. While sulfates would be
likely to offset warming, it’s not clear exactly how they would counteract some of the other effects of
greenhouse gases, particularly changes in precipitation patterns. And SRM would do nothing to reduce
the acidification of the oceans caused by rising levels of carbon dioxide in the atmosphere.
While sulfates would be likely to offset warming, it’s
not clear how they would affect precipitation.
“The term ‘solar radiation management’ is positively Orwellian,” says Raymond Pierrehumbert, a
geophysicist at the University of Chicago. “It’s meant to give you a feeling that we really understand what
we would be doing. It’s a way to increase comfort levels with this crazy idea. What we’re really talking
about is hacking the planet in a case where we don’t really know what it is going to do.” In delivering the
prestigious Tyndall Lecture at the annual American Geophysical Union meeting last December, he said
the idea of putting sulfate aerosols in the stratosphere was “barking mad.”
Pierrehumbert also rejects the value of doing field experiments. “The whole idea of geoengineering is so
crazy and would lead to such bad consequences, it really is pretty pointless. We already know enough
about sulfate albedo engineering to know it would put the world in a really precarious state. Field
experiments are really a dangerous step on the way to deployment, and I have a lot of doubts what
would actually be learned.”
The fundamental problem with albedo engineering, says Pierrehumbert, is that once we start using it,
we’ll need to continue indefinitely. Since it only offsets warming, once the process stops, temperature
changes
caused by greenhouse gases will manifest themselves suddenly and dramatically. “If you
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stop—or if you have to stop—then you’re toast,” he says. Even using it as a temporary Band-Aid doesn’t
make
sense,
he argues:
to the
point
in terms of climate
changes that you feel you have to
Meet the
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and Easyyou
Planget
to Stop
Global
War...
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use it, then you have to use [SRM] forever.” He believes that this makes the idea a “complete
nonstarter.”
Besides, Pierrehumbert says, our climate models “are nowhere near advanced enough for us to begin
thinking of actually engineering the planet.” In particular, computer models don’t accurately predict
specific regional precipitation patterns. And, he says, it’s not possible to use existing models to know
how geoengineering might affect, say, India’s monsoons or precipitation in such drought-prone areas as
northern Africa. “Our ability to actually say what the regional climate patterns will be in a geoengineered
world is very limited,” he says.
Alan Robock, meanwhile, has a long list of questions concerning SRM, at the top of which is: can it even
be done? Robock, an expert on how volcanoes affect climate and a professor of environmental sciences
at Rutgers University, cautions that while the Pinatubo eruption confirmed the cooling effect of sulfate
aerosols, it injected a massive amount of sulfur dioxide into the stratosphere over a few days. Solar
geoengineering would use far less sulfur but disperse it continuously over an extended period. That
could be a critical difference. The optimal way to achieve SRM is with sulfur particles only about half a
micrometer in diameter. Sunlight reflects off the surface of the particles, and smaller particles have more
surface area than larger ones, making them far more efficient at blocking the sun. Robock worries that
as sulfur is continuously injected and concentrations build up, the small particles will clump together into
large ones, necessitating far more sulfur than some current proposals assume.
These details of aerosol chemistry could help determine the viability of SRM. “David [Keith] thinks it is
going to be easy and cheap, and I don’t agree,” says Robock. He estimates that several million tons of
sulfur would have to be injected into the atmosphere annually to offset doubled levels of carbon dioxide,
but if the particles clump together, “it could be many times that.”
Research so far shows that producing a cloud in the stratosphere—Robock’s preferred description of
SRM—”could cool the climate,” he says. “But you would have a very different planet, and other things
could be worse.” He points out, for example, that in the aftermath of Mount Pinatubo, rainfall decreased
significantly in some parts of the world. Robock supports more modeling on solar geoengineering, but
“right now, I don’t see a path in which it would be used,” he says. “I don’t see how the benefits outweigh
the negatives.”
Still, climate scientists differ widely in the way they interpret the research on those risks. Phil Rasch, for
one, who is chief scientist for climate science at the Pacific Northwest Laboratory in Richland,
Washington, cautiously says the models do not yet indicate “showstoppers” that would preclude
consideration of certain SRM strategies.
Rasch, who published a paper with Crutzen in 2008 on using sulfate aerosols for geoengineering, says
research shows that the particles will cause some ozone depletion—”it is absolutely something we need
to pay attention to”—but that the loss of ozone is somewhat tempered by the ability of the sulfate
particles to block ultraviolet radiation. As for rainfall, he says, models tend to agree that SRM “leads to a
[future] world that’s closer to the present day with respect to precipitation than if you don’t
geoengineer.” Overall, says Rasch, SRM would stave off some effects of climate change, though “some
parts
6 of 9 of the planet are more strongly affected than others, and there are many issues that remain
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unexplored.”
Meet the Man with a Cheap and Easy Plan to Stop Global War...
http://www.technologyreview.com/featuredstory/511016/a-chea...
“The
term ‘solar radiation management’
is positively
Orwellian. It’s a way to increase comfort levels with
this crazy idea.” —Raymond Pierrehumbert
A Moratorium
The scientific uncertainties and the prospect of winners and losers among different parts of the world
make it almost unfathomably difficult to envision how SRM might be appropriately implemented and
controlled. How could we fashion the international system of governance that would eventually be
needed? Who would decide how and when to implement the technology? Who would monitor and
control it? Who would set Earth’s thermostat and at what temperature? If anything, the questions about
who would make the decisions on solar geoengineering are more daunting than the questions about the
science itself.
While the need for international governance is still years in the future, Keith and several close
collaborators, including Edward Parson, a law professor at the University of California, Los Angeles, are
already thinking about how such a system might evolve. Research on the technology is key, Parson says,
to achieving a better understanding of what solar geoengineering can do and what the risks are. Without
such knowledge, he says, “you don’t know what you need to govern.”
The controversy over field experiments, such as the ones Keith and Anderson are designing, is emerging
as an early battleground for the social and political issues. Keith is adamant that work will not go forward
unless he and his colleagues receive public funding and approval from established scientific agencies.
Indeed, he and his collaborators see the experiments as an early test not only for the technology but
also for how a governance system can work. The hope, says Parson, is that the funding and approval
process could provide an opportunity to establish “norms” that will help shape longer-term discussions
—standards such as transparency, public review, and open disclosure of the results.
No one thinks that field experiments involving tiny amounts of sulfur would be physically dangerous,
says Parson. “What concerns people,” he says, “is the political and social consequences of the research
going ahead, followed by bigger and bigger experiments—and then you’re on the slippery slope all the
way to full-scale deployment.” These worries should be taken seriously, he says: “You need to
encourage small-scale research, but you need some kind of limited governance to mitigate the risk of a
slide to deployment.” Established scientific funding agencies could probably take care of that, he
believes. And he suggests that early experiments must be strictly limited, and researchers need to
clearly state that no one is going to do anything big for the time being.
Keith and his collaborators are pushing fellow researchers to sign an agreement that would “function
like a moratorium” on deploying solar engineering. That, Keith believes, could calm fears that some are
rushing ahead on the technology—worries that he concedes are “not ungrounded,” since there are, in
fact, no international laws or regulations barring anyone from implementing geoengineering schemes. By
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signing a moratorium, he hopes, scientists could “help free up research” on the risks and efficacy of
SRM.
Switching
It On
Meet the Man
with a Cheap and Easy Plan to Stop Global War...
http://www.technologyreview.com/featuredstory/511016/a-chea...
For very brief spells, Keith sometimes lapses into animated annoyance with SRM critics. A moment later,
however, he is calmly and logically countering the criticism with responses he has developed after years
of thinking and writing about geoengineering. He sketches a graph showing that, in fact, sulfur injection
could be rationally ended a century or less after it’s begun; while the underlying climate changes it was
masking would return, the rate of change affecting ecosystems and humans would have been slowed
and managed. The idea that initiating SRM would commit us to continuing it indefinitely “is just not true,”
he states with characteristic self-confidence.
It would be an extreme action, creating a different
planet—even the color of the sky would be whiter.
Even many of the strongest advocates of SRM research say the technology would be a nearly
unthinkable last resort for a desperate world facing climate changes so destructive that the risks would
be worth taking. Keith, however, has a far less apocalyptic vision. “If we’ve actually found something that
could substantially reduce the risk of climate change over the next century and save a lot of lives, that’s
nothing to be upset about,” he says. “It’s something to celebrate.” In fact, he says framing the case for
geoengineering as a last resort in a climate emergency is “a bit of a rhetorical trick”: it leaves undefined
what a “climate emergency” is, and “there is no simple definition.”
The approach Keith proposes is at once more deliberate and far more radical: “In my view, we should
begin real research now, and if it bears out that [SRM] could meaningfully reduce climate risks without
too many risks of its own—which may or may not turn out to be true—then we should actually begin
doing this relatively soon, but with a very slow ramp.” He believes the technology could be ready to be
deployed as early as 2020 (or, more realistically, 2030) and would involve levels of stratospheric sulfur
“practically” within normal ranges for the first decade. The process could be monitored and evaluated,
and because the amounts of sulfur injected into the stratosphere would be relatively small, “the chances
of a big problem are pretty close to zero.”
It is often assumed that SRM would be “turned on with a big switch,” says Keith. “But there’s no reason
you can’t ramp it up.” And that ability to turn on the system slowly and with minimal risk is behind his
“willingness to take geoengineering seriously,” he says: “If it was a one-time decision, I would be much
more skeptical about doing it. It would be very hard to persuade me that it was sensible.” Given the
possibility of a more deliberate approach, “I lean pretty strongly, I got to say, to doing it.”
Listening to Keith’s logical arguments and careful descriptions of how SRM might be carried out, it’s just
possible to start believing that intentionally adjusting the climate wouldn’t be an extreme action. But it
would. It would create a different planet—even the color of the sky would be whiter. And it would almost
certainly be driven by desperation. On the other hand, the buildup of greenhouse gases is already
altering the atmosphere and climate in an unprecedented and uncontrolled manner. How big a leap is it
to intentionally “engineer” ways to begin counteracting that? And Keith is surely right that climate
researchers should explore solar geoengineering to determine whether it would actually work and how
safe it would be, and that political scientists need to start thinking about how we might implement such
8 ofunprecedented
9
an
planetary project. All that will be left then is for society and governments to face the 11/29/15, 8:55 PM
impossibly difficult task of deciding whether to do it.
Meet the Man with a Cheap and Easy Plan to Stop Global War...
http://www.technologyreview.com/featuredstory/511016/a-chea...
Credits: Grafilu
Tagged: Business, Energy, climate change, global warming, David Keith
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