THE BLOG

Geoengineering: Mankind and Reshaping the World

05/14/2009 05:12 am ET | Updated May 25, 2011

If he were a bear, John Holdren would be reaching into a bee's nest. The president's science advisor seems undeterred about stirring up an angry environmental buzz.

Holdren revealed to the Associated Press this week that the administration is actively talking about geoengineering as a tool to blunt global warming. Geoengineering embraces a range of futuristic schemes, ranging from the fantastical to the merely brazen, to try to alter the environment.

It includes ideas like shooting sulfur into the air to create a cooling atmospheric blanket. It includes launching micro-thin disks to create a floating sun shade a million miles out in space. It includes fake trees that would absorb carbon dioxide, fertilizing the ocean to grow huge slimes of algae, or turning the oceans upside-down with thousands if pipes reaching to cooler depths.

The reaction was expectable. Those who take the Holden at his word--and the Harvard scientist is far too bright to dismiss--find the prospect of geoengineering frightening. Man does not know enough to muck around with earth's systems, they argue; surely these notions are too preposterous to be taken seriously.

But in truth, man has long tried to reshape the world. We have scraped away forests where we wanted fields. We have built dams to create lakes above valleys. We have leveled hills and bored through mountains when they were in our way. We have drained swamps when we wanted to make more dry land. We have carved canals and ditches to make water flow to places it did not.

Much of this was simply digging large, the exaggeration of our childhood urge to carve castles in the sand. We were a little more timid about purposely tinkering with the fundamental systems of nature.

But World War II gave us hubris. The vast scale of that conflict made us think in larger terms. Suddenly, our reach was the whole world. The technology that burst--literally--from the war made us feel we could master larger forces than we had known. The war had seemed such an apocalyptic test by the gods, the winners saw our unequivocal victory as evidence we were the masters of our own fate, and certainly of our world.

The science of trying to change the weather was born in that war. A high school dropout with a self-taught knack for research named Vincent J. Schaefer was trying to figure out how to counteract the ice buildup on the wings of bombers when he accidentally discovered how to create snow from dry ice.

In 1946, flying in a plane over Mount Greylock, Massachusetts, he threw dry ice and silver iodide from the cockpit, and precipitation fell. From that came a generation of airborne cloud seeders who fly today in the American west to squeeze a bit more precipitation onto farms and dams below.

We were emboldened by such successes to dream large. The Russians plotted to turn Siberian Rivers from the Arctic to empty on central Asian farmlands. They proposed damming the Bering Strait, pumping water into the Pacific to make the Arctic Ocean so salty the icepack would melt. They launched Sputnik to defy our earth-bound limits, and America trumped that by sending a man to the moon. Less nobly, the Pentagon secretly worked on plans to alter the climate to use as a weapon in war.

When the public learned, belatedly in 1974, the Pentagon had carried out a broad and failed scheme to alter the climate over the Ho Chi Minh trail in the Vietnam War to make it impassable, and had tried to denude its forest canopy with Agent Orange, sentiment turned against what seemed like Strangelovian schemes. Talk of grand scale geophysical tinkering subsided for a while, though some scientists still made musings on the back of envelopes, doodling with what-if-we-did-this notions.

By the 1980s, though, it was becoming clear that we were already doing something to change our world. We were pumping so much carbon dioxide and other industrial gases into the air that our thin atmosphere was like a scientific beaker already frantic with the results of a rogue experiment.

We were heating our world. The implications were a mystery. The early results did not look good. And so, by a 1991 meeting of a panel of the National Academy of Sciences, the envelopes had come back out, revealing the figures and equations that their authors said just might save us. The geoengineering schemes were rehatched.

The theorists now touting these schemes are hardly mad scientists, bent on playing god. One, Paul Crutzen, is a Nobel prizewinner who helped mend the ozone hole. The National Academy of Sciences, several respectable universities, and NASA all have put up money or support to keep the plans alive.

Many of the ideas are impractical, enormously expensive, and certainly would create a political morass with other countries, not to mention our own. But the supporters of these ideas say it is foolish to blunder ahead toward predictions of climate change chaos without at least a few exit strategies, as desperate as they may seem.

"We don't have the luxury," Holdren said, "of ruling any approach off the table."