Engineering the climate - From PRI's The World

Engineering the climate
From PRI's The World 19 April, 2010 07:23:00

Geoengineering could help with climate change, but the possibility of massive climate interventions raises big concerns.

This story is adapted from a broadcast audio segment; use audio player to listen to story in its entirety.

Story by Alex Gallafent, PRI's "The World"

An environmental problem of a whole different order has got scientists and policy makers around the world contemplating drastic measures. They fear that governments aren’t doing enough to cut the pollution that’s contributing to climate change, so they’re considering something they call geo-engineering. They’re exploring technologies that could cool the planet and avoid the catastrophes that a warmer earth might suffer. But the possibility of massive climate interventions is raising big ethical and geo-political concerns.

It sounds like an evil plot: deliberately changing the global climate. And at first glance, you’d think geoengineering would be the domain of evil cranks and megalomaniacs. But Eli Kintisch, who actually met a few would-be geoengineers while writing his book "Hack the Planet," says that couldn't be further from the truth.

"Unfortunately they were clear thinking, responsible, highly cited scientists; some of the giants in the field. And that’s really scary."

Then again, many considered these scary times. We’re already conducting a massive unintentional geoengineering experiment by injecting millions of tons of heat-trapping pollution into the atmosphere.

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http://washingtonindependent.com/82450/a-radical-climate-solution-goes-mainstream
A Radical Climate Solution Goes Mainstream
As Scientific Consensus on Geoengineering Forms, Politics Lag Behind
By Aaron Wiener 4/16/10 6:00 AM

The scientific consensus on geoengineering — a manipulation of the environment to counteract climate change — has come a long way in the past few years. As recently as 2006, it was unthinkable to many climate scientists that leaders in their field would seriously consider the idea of shooting reflective particles into the atmosphere or dumping massive quantities of iron into the oceans.
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Geoengineering takes two principal forms. One involves increasing the planet’s reflectivity in some way, so that less sunlight warms the earth and temperatures drop. This approach can be as simple as Energy Secretary Steven Chu’s proposal to paint roofs white (although that would barely make a dent in global warming) or as complex as replicating the effects of a volcano by shooting sulfur dioxide into the upper atmosphere. It can be done rather inexpensively — some experts say a sulfur dioxide injection would cost under 3 cents per ton of carbon negated, compared to the $10- to $30-per-ton pricetag that comprehensive climate legislation would likely impose — but it’s only a patch: Carbon levels would continue to rise, and if geoengineering efforts stopped, temperatures would shoot up.

The other form involves sucking carbon out of the atmosphere, potentially by adding iron to the oceans to encourage carbon-absorbing algae blooms or by pulling carbon out of the air and sending it deep underground. This approach would actually reduce our carbon levels and could avoid some of the ethical issues of reflectivity engineering, but it’s likely to be much more expensive and slower to take effect, and it presents its own host of practical concerns.