Terraforming works, so what happens now?

This is the century of terraforming.

Terraforming (Earth-shaping) was popular in the science fiction of the last century.

In his Mars Trilogy, Kim Stanley Robinson produces a future history in which Mars is transformed, using the technologies that produce global warming, into an Earth-like planet where plants can grow.

Robinson is not unique in having imagined terraforming but the science works well in this case, serving the larger story. (That's the cover of Robinson's book from Wikipedia.)

But global warming is transforming our own Earth, faster than perhaps we know, and the question is whether we can do anything about it, whether Earth can be re-formed.

A July report in Russian Meteorology and Hydrology suggests the answer is yes. Scientists found a way to spray sulfates at altitude and found they could block a material amount of sunlight.

The book Superfreakonomics takes this idea a step forward, making it one of the most controversial books of the year.

In a chapter titled "What do Al Gore and Mount Pinatubo have in common," the authors suggest that it's impossible to turn around current trends, and copying processes by which the Earth naturally cools, like volcanic eruptions, might be worth a try.

Environmentalists have been seeking to debunk the book ever since. Author Stephen Dubner calls their whole effort a smear. "Let the wild rumpus start," he writes gleefully.

But policymakers, who feel a need to deal with whatever reality develops, are taking terraforming seriously. A workshop last spring examined the possibilities, but even the scientists involved admitted to some ambivalence.

An experiment on a global scale can't be undone if the theory it tests proves wrong. But such an experiment is already underway. Rather than using terraforming to secure Mars, it is possible we'll be using it in your lifetime to save Earth.

This post was originally published on Smartplanet.com