Michael Specter: The Climate Fixers

‘Is there a technological solution to global warming?’

A: In truth, no. There is no such thing as a ‘solution’ in the absence of a problem.

Have no illusions, JunkScience.com encourages greenhouse hysterics to discuss geoengineering (endlessly, preferably). Our reasoning is simple – they’ll never find a temperature/precipitation regime to suit more than a couple of countries, far less all the Kyoto signatories, so they’ll never actually do anything but talk about it. We see that as being as good a way as any to get them to sit on their hands and don’t touch nothin’.

Unfortunately, some seem to be taking the idea seriously.

Late in the afternoon on April 2, 1991, Mt. Pinatubo, a volcano on the Philippine island of Luzon, began to rumble with a series of the powerful steam explosions that typically precede an eruption. Pinatubo had been dormant for more than four centuries, and in the volcanological world the mountain had become little more than a footnote. The tremors continued in a steady crescendo for the next two months, until June 15th, when the mountain exploded with enough force to expel molten lava at the speed of six hundred miles an hour. The lava flooded a two-hundred-and-fifty-square-mile area, requiring the evacuation of two hundred thousand people.

Within hours, the plume of gas and ash had penetrated the stratosphere, eventually reaching an altitude of twenty-one miles. Three weeks later, an aerosol cloud had encircled the earth, and it remained for nearly two years. Twenty million metric tons of sulfur dioxide mixed with droplets of water, creating a kind of gaseous mirror, which reflected solar rays back into the sky. Throughout 1992 and 1993, the amount of sunlight that reached the surface of the earth was reduced by more than ten per cent.

The heavy industrial activity of the previous hundred years had caused the earth’s climate to warm by roughly three-quarters of a degree Celsius, helping to make the twentieth century the hottest in at least a thousand years. The eruption of Mt. Pinatubo, however, reduced global temperatures by nearly that much in a single year. It also disrupted patterns of precipitation throughout the planet. It is believed to have influenced events as varied as floods along the Mississippi River in 1993 and, later that year, the drought that devastated the African Sahel. Most people considered the eruption a calamity.

For geophysical scientists, though, Mt. Pinatubo provided the best model in at least a century to help us understand what might happen if humans attempted to ameliorate global warming by deliberately altering the climate of the earth.

For years, even to entertain the possibility of human intervention on such a scale—geoengineering, as the practice is known—has been denounced as hubris. Predicting long-term climatic behavior by using computer models has proved difficult, and the notion of fiddling with the planet’s climate based on the results generated by those models worries even scientists who are fully engaged in the research. “There will be no easy victories, but at some point we are going to have to take the facts seriously,’’ David Keith, a professor of engineering and public policy at Harvard and one of geoengineering’s most thoughtful supporters, told me. “Nonetheless,’’ he added, “it is hyperbolic to say this, but no less true: when you start to reflect light away from the planet, you can easily imagine a chain of events that would extinguish life on earth.”

New Yorker