*From the Los Angeles Times*
Solving global warming with giant vacuums The technology works, but it would
require millions of carbon dioxide filters across the planet at a cost of
trillions of dollars a year.
By lan Zarembo
Los Angeles Times Staff Writer

April 29, 2008

Here's a simple solution to global warming: vacuum carbon dioxide out of the

Klaus Lackner, a physicist at Columbia University, said placing enough
carbon filters around the planet could reel the world's atmosphere back
toward the 18th century, like a climatic time machine.

After a decade of work, his shower-sized prototype whirs away inside a
Tucson warehouse, each day capturing about 10 pounds of the heat-trapping
greenhouse gas as air wafts through it.

Only a few billion tons to go.

In the battle against global warming, technology has long been seen as the
ultimate savior, but Lackner's machine is a clunky reminder of how distant
that dream is.

He estimates that sucking up the current stream of emissions would require
about 67 million boxcar-sized filters at a cost of trillions of dollars a

The orchards of filters would have to be powered by complexes of new nuclear
plants, dams, solar farms or other clean-energy sources to avoid adding more
pollution to the atmosphere.

Despite the scope of the proposal, the allure of high technology is
irresistible for modern humans. Salvation has arrived again and again over
the last century: the automobile, the jet, the Internet, the iPod.

That dream has pushed scattered groups of scientists to work on massive
schemes to reengineer the planet.

One idea is to block sunlight, either by constructing artificial volcanoes
to blast sulfur particles into the atmosphere or by launching millions of
tiny satellites into space and arranging them into a giant mirror.

Another concept is sprinkling iron over the oceans to nurture plankton
colonies that would absorb carbon dioxide from the air and transfer it to
the depths.

But while the science of dialing back the planet's thermostat is
straightforward, the execution is fabulously expensive, complex and
grandiose on a scale that boggles the mind.

"Nobody doubts it is possible to take CO2 out of the air," said David Keith,
a professor of engineering and economics at the University of Calgary in
Canada and one of several scientists around the world working on the
problem. "The issue is, 'What does it cost?' "

Some policy experts argue that blind faith in technology is a harmful
distraction from the hard sacrifices needed to control global warming.

"The temptation is to say, 'Let's get John Wayne on horseback or Bill Gates
. . . and solve this problem,' " said Dale Jamieson, director of
environmental studies at New York University.

But some scientists say that the potential of such ideas cannot be ignored
given the world's political paralysis on controlling emissions and its
myopic addiction to cheap and dirty coal.

"There are not that many alternatives," Lackner said.

The attraction of a technological silver bullet lies in the failure of the
world to solve global warming through the obvious solution: reducing

The 1997 Kyoto accords were supposed to bring the world together to address
the problem, but the two biggest polluters, the United States and China,
have refused to cap their emissions, and Europe is failing to meet even its
modest targets.

Worldwide annual emissions of carbon dioxide -- the main culprit in global
warming -- have climbed 28% over the last decade, according to the U.S.
Department of Energy. The rise has been largely driven by industrializing
countries, such as China and India, which argue that they have the right to
exploit their coal reserves to catch up with the West.

It is clear that cheap energy is a drug that civilization will not give up.
But big technological solutions could allow society to keep its drug.

Among the options, carbon filtering is the most direct and best understood.
If industrialization is a process of transferring carbon stored in the earth
to the atmosphere, filtering seeks to put it back.

The technology is decades old. Bottled oxygen used in hospitals started out
as plain air before nitrogen, carbon dioxide and other gases were filtered
out. Space capsules and submarines extract carbon dioxide to maintain
breathable air for crew members.

The process for removing atmospheric carbon involves putting one compound,
usually a hydroxide, in contact with the air, setting off a reaction that
grabs CO2 and incorporates its carbon atoms into a carbonate compound.

Then, in a reaction that requires a large input of heat, the carbonate
compound is broken apart, reconstituting and trapping the carbon dioxide.

Researchers propose pumping the captured CO2 into the ground, a practice
already used to increase the pressure in oil wells. Geologists say there is
room in subterranean rock formations to lock it away forever.

The beauty of carbon capture is that it scrubs the planet without intruding
on it, unlike artificial volcanoes and sun reflectors, which could cause
enormous planetary damage in the form of acid rain or giant shadows that
stunt crops.

The filters could be placed anywhere in the world, since carbon dioxide
disperses throughout the atmosphere.

For all its appeal, the process is hideously inefficient. Carbon dioxide
makes up less than 0.04% of the atmosphere, and removing climate-changing
quantities of it requires filtering massive amounts of air.

Lackner calculated that sucking up all 28 billion tons of CO2 released
worldwide each year would require spreading out his machines over a land
area the size of Arizona.

That seems like a reasonable sacrifice to save civilization, until you
consider the expense.

Experts estimate that it would cost up to $200 a ton to filter and store
carbon dioxide from the air. That means the yearly vacuuming bill could
reach $5.6 trillion.

Even filtering the greenhouse gas from smokestacks, where it is hundreds of
times more concentrated and thus much cheaper to capture, is still deemed
too expensive for commercial use.

The enormous cost raises the question: Who would pay?

It is the same impasse that has stymied efforts toward a global agreement to
reduce emissions. China argues that the West should foot the bill because it
created the problem over the last two centuries. The United States says
China must accept its share of responsibility as the world's new top

The cost of the technology will surely fall over time, but without
government action that is unlikely to happen soon enough to stave off the
worst effects of climate change.

Without at least a 50% cut in emissions by mid-century, the United Nations'
Intergovernmental Panel on Climate Change predicts that the temperature rise
will exceed 2 degrees, resulting in worsening drought, a dangerous sea level
rise and widespread extinction of species.

Paul Crutzen, a Nobel Prize-winning atmospheric chemist at the Max Planck
Institute for Chemistry in Mainz, Germany, said that the failure to cut
emissions might force the world to reshape the environment through drastic
use of technology.

The risks could be enormous, but the risks of failing to reduce emissions
could be greater, he said.

Crutzen said that only out of a "sense of despair" had he come to favor the
last-ditch option of spewing more than a million tons of sulfur a year into
the air.

It's a dirty proposition that, in some ways, is its own environmental crime.
But it works, as shown by the 1991 Mt. Pinatubo eruption in the Philippines,
which temporarily cooled the planet by almost 1 degree Fahrenheit. "It might
be the last escape route from the problem," he said.

The power to reengineer the planet raises another question: Who gets to
control the thermostat? Despite the perception that climate change is a
global problem, it is in reality a series of regional transformations that
benefits some places and harms others.

Countries in the far northern latitudes have less incentive than tropical
countries to counteract the warming. Russia has already laid claim to the
North Pole in hopes that the arctic thaw will open access to new oil
reserves. Canada is pondering the possibility of its vast expanse of tundra
becoming a breadbasket.

With enough carbon filters, a single country or even several rich
individuals would have the power to set the world's temperature.

"No matter how you go about it, there will be a lot of politics," Lackner

For now, his machine, a solitary prototype, continues to hum away in the
Tucson warehouse. With no good place to store the carbon dioxide it traps,
the gas is simply released back into the air.

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Michael Balter
Contributing Correspondent, Science
Adjunct Professor of Journalism,
Boston University

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