Scientists weigh risks of climate 'techno-fixes'
Schemes from space mirrors to vast algal blooms have sparked debate
over the ethics of geoengineering.

By Moises Velasquez-Manoff | Correspondent of The Christian Science
Monitor
http://www.csmonitor.com/2007/0329/p13s02-sten.html

Faced with the specter of a warming planet and frustrated by the lack
of progress on this time-sensitive issue, some scientists have begun
researching backup plans. They seek a way to give humanity direct
control over Earth's thermostat.

Proposals run the gamut from space mirrors deflecting a portion of the
sun's energy to promoting vast marine algal blooms to suck carbon out
of the atmosphere. The schemes have sparked a debate over the ethics
of climate manipulation, especially when the uncertainties are vast
and the stakes so high. For many scientists, the technology is less an
issue than the decisionmaking process that may lead to its
implementation.

Environmental policy driven purely by cost-benefit analyses cannot,
they say, effectively point the way on large issues like climate
change. But even as many scientists caution against unintended, even
catastrophic consequences of tinkering with climate, they concede that
the more tools humankind has to confront a serious problem, the
better.

Others wonder if the mere hint of a quick-fix solution will only
provide a false sense of security and hamper efforts to address the
root problem: carbon emissions from a fossil fuel-based economy. And
then there's the trillion-dollar question: In a politically fractured
world, how will technologies that affect everyone be implemented by
the few, the rich, and the tech-savvy?

When scientists talk about geoengineering, they generally mean
subtracting a fraction of the sun's energy from the earth equal to
that trapped by human-emitted greenhouse gases.

It is not a new idea,
but only recently has it moved toward the scientific mainstream. In
2006, Nobel Laureate Paul Crutzen of the Max Planck Institute for
Chemistry in Mainz, Germany, published a paper on injecting particles
into the upper atmosphere to reflect incoming sunlight and cool the
earth.

Climate scientists have since run scenarios on climate models
and first reports found that it might work. In November last year,
NASA cohosted a conference on the topic.

It takes only a cursory look at this century's forecast to see the
utility of a climate control switch. Currently at 380 parts per
million, carbon-dioxide emissions are predicted to double their
preindustrial rates, to about 500 ppm, by 2100. Last time there was
that much CO2 in the air, palm trees grew in Antarctica and crocodiles
sloshed about in the swamps of a tepid Greenland.

The Intergovernmental Panel on Climate Change predicts a temperature
increase of 5.4 degrees F. by century's end. It also predicts that,
assuming continued emissions, heat stored in the ocean will continue
to warm the planet for a thousand years. This last point – that even
if we stop all greenhouse-gas emissions tomorrow we're in for a
certain amount of warming – is reason enough to look into
geoengineering, says Jamais Cascio, a futurist and cofounder of the
website worldchanging.com. "If you find yourself in a hole, the first
step is to stop digging," he says. "But stopping digging isn't going
to get you out of your hole."

By some estimates, geoengineering has the added allure of being
cheaper than curbing emissions. Economists say that decarbonizing the
economy will cost around 2 percent of the gross domestic product;
putting reflective aerosols into the upper atmosphere will cost about
one-thousandth of that, says Ken Caldeira, a climate scientist at the
Carnegie Institution at Stanford University.

But others say the discussion over mitigation seems to have gotten
ahead of itself. Why talk about fixing symptoms when we have the
technology to address the root cause? "There's no getting around the
fact that we're in a very desperate situation," says Bill McKibben,
author of "The End of Nature" and more recently "Deep Economy." But
"before geoengineering, let's do a little policy engineering first."

History seems to support Mr. McKibben's critique. The Clean Air and
Clean Water Acts of the 1960s and 1970s, which cost more than the
estimates for curbing emissions today, are seen in retrospect as
absolutely the right thing to have done. That such costs are now
viewed as untenable speaks to the shortcomings of the cost-benefit
approach that has driven environmental policy for the past 25 years,

says Frank Ackerman, director of research and policy program at the
Global Development and Environment Institute at Tufts University in
Medford, Mass.

Simply put, economic analyses can't deal with far-reaching, long-term
problems like climate change or geoengineering, he says. There are too
many unknowns. "Changing the earth's climate is an experiment we're
going to do once," he says. "There are not going to be any do-overs."

For this reason, many call global warming a moral issue, not an
economic one. There are certain relationships that cannot be assigned
numerical values. "If you just looked at it from a cost-benefit point
of view, Central Park is completely irrational," says Dale Jamieson,
director of environmental studies at New York University. "Yet, nobody
would think that the fact you can sell Central Park to Donald Trump is
reason to do it."

Others point out that the mere mention of a techno-fix for climate
change could have unintended consequences. If people know that someone
will bail them out of catastrophe, they're more inclined to engage in
risky behavior, says David Keith, director of an energy and
environmental systems research group at the University of Calgary.
Statistically speaking, those with flood insurance suffer the worst
flood damage, he says. And because geoengineering may lead to greater
risk-taking – in this case by continuing to emit copious amounts of
CO2 – "it's clearly not, in some global sense, economically optimal,"
says Mr. Keith.

But Mr. Cascio points out that fail-safe technologies could also drive
humanity in the other direction. If people understand that these
technologies are a terrible last resort, the specter of their
deployment may serve as a deterrent the way mutually assured
destruction (theoretically) saved the world from a nuclear holocaust
during the cold war. The parallel has to be made clear: "You are
consciously trying to alter the complex systems that govern how our
planet operates," he says. "Do that the wrong way, and you potentially
kill everyone."

Not discussing these options could be worse, says Scott Barrett,
professor of environmental economics at Johns Hopkins University in
Washington, D.C. If scientists don't talk about geoengineering, the
institutions and regulations governing its implementation will not be
created. "The point may come where countries may experiment and there
will be no international arrangements," Professor Barrett says.

We have to "bring this thing out into the open."

Because climate change has winners and losers – one country's
breadbasket dries up while another's desert blooms – unilateral change
becomes a sticky prospect. Manipulation – even if it's viewed as a
corrective measure – will inevitably impinge on another's newfound
good fortune. "Even if you're very confident that you can make things
better, that doesn't necessarily give you the right to do that if, in
fact, you're affecting other people's interests," says Professor
Jamieson.

Ken Caldeira posits another possibility: "You could imagine some kind
of arms race of geoengineering, where one country is trying to cool
the planet and another is trying to warm the planet," he says.