As the threat of global warming grows more urgent, a few scientists are considering radical—and possibly extremely dangerous—schemes for reengineering the climate by brute force. Their ideas are technologically plausible and quite cheap. So cheap, in fact, that a rich and committed environmentalist could act on them tomorrow. And that’s the scariest part.
Graeme Wood in The Atlantic:
If we were transported forward in time, to an Earth ravaged by catastrophic climate change, we might see long, delicate strands of fire hose stretching into the sky, like spaghetti, attached to zeppelins hovering 65,000 feet in the air. Factories on the ground would pump 10 kilos of sulfur dioxide up through those hoses every second. And at the top, the hoses would cough a sulfurous pall into the sky. At sunset on some parts of the planet, these puffs of aerosolized pollutant would glow a dramatic red, like the skies in Blade Runner. During the day, they would shield the planet from the sun’s full force, keeping temperatures cool—as long as the puffing never ceased.
Technology that could redden the skies and chill the planet is available right now. Within a few years we could cool the Earth to temperatures not regularly seen since James Watt’s steam engine belched its first smoky plume in the late 18th century. And we could do it cheaply: $100 billion could reverse anthropogenic climate change entirely, and some experts suspect that a hundredth of that sum could suffice. To stop global warming the old-fashioned way, by cutting carbon emissions, would cost on the order of $1 trillion yearly. If this idea sounds unlikely, consider that President Obama’s science adviser, John Holdren, said in April that he thought the administration would consider it, “if we get desperate enough.” And if it sounds dystopian or futuristic, consider that Blade Runner was set in 2019, not long after Obama would complete a second term.