Text by Andy Isaacson
Earlier this year, a team of scientists dumped several tons of iron into the Atlantic Ocean off the Chilean coast, hoping to fuel a massive algae bloom (algae eat iron), which would in turn suck up massive amounts of CO2 from the air. Instead, shrimp wolfed down the algae, causing yet another wrinkle in the complex world of geoengineering.
Expect to hear that buzzword more often. Generally speaking, geoengineering is the large-scale manipulation of the environment to counter climate change. And though the concept has been around for decades, worsening warming trends are pushing it into the spotlight.
Even President Obama’s science and technology adviser, John Holdren, has expressed interest in the subject. Proposed methods for cooling the Earth include building carbon-scrubbing towers that would capture CO2 from the atmosphere, and shooting droplets of seawater into clouds to enhance their reflectivity. In September, Britain’s Royal Society will release a report on which geoengineering ideas (e.g., a plan to reflect solar radiation by timed release of sulfur dioxide into the stratosphere) deserve further research. Many scientists worry that attempts to fool Mother Nature will create bigger problems than those they aim to solve. “It’s best to start testing these things gradually, so if something bad happens you can back off,” says Ken Caldeira, a Carnegie Institution climate scientist who champions the sulfur dioxide idea. But if a true emergency were to arise? “I think we could be putting particles in the stratosphere next year,” Caldeira says. “The technology is there.”