Do We Test Geoengineering? (Asilomar Dispatch 3)

 

For years, climate scientists have used computer modeling rather than field tests to predict the likely effects of certain geoengineering methods—like whitening clouds or dispersing sulfur particles into the upper atmosphere to reflect the sun’s rays back into space. But at last week’s Asilomar International Conference on Climate Intervention Technologies, researchers were divided over whether models are enough.

In one corner was Alan Robock, a professor at Rutgers University who has spent most of his career modeling the climate-cooling effects of volcanic eruptions—which spew sulfur dioxide into the upper atmosphere. Indeed, it was knowledge gained from the 1991 eruption of Mount Pinatubu in the Philippines (here’s a pdf of one of Robock’s papers) that inspired one of the more controversial geoengineering schemes. Robock says that one recent Russian eruption he is studying put more sulfur in the atmosphere than any scientific team would likely deliver. “So why do we have to actually do tests?” he asks.

Robock has no problem with small-scale testing of the equipment and mechanisms that humans might need to introduce sulfur into the atmosphere, or to make sure we have the right gear to whiten clouds. But computer models, he argues, can already predict how the atmosphere will react to a global-scale release. And scientists can ensure accuracy by cross-checking their results against those obtained by dozens of colleagues.

Not so, counters fellow Asilomar attendee David Keith, who studies climate at the University of Calgary. “I work in experiment and theory,” he says. “If you just do theory, you miss stuff.” The presence of the ozone hole, he notes, was confirmed by ground readings in Antarctica; researchers crunching the satellite data had dismissed readings indicating that ozone was being depleted. “It took a real human presence to get it right,” Keith says.

To really understand the planetary response to something as massive as lacing the upper atmosphere with sulfur, he adds, you have to do it on a large scale and over long periods—maybe as long as a decade. Otherwise, Keith says, you won’t be able to distinguish between natural weather variations and variations caused by the experiment.

But this very difficulty, Robock insists, is precisely why computer models are superior: You can tweak your models and run them over and over to find variations in the results. “No one gets hurt,” he says. Ah, counters Keith, but what if you’ve got it wrong? “With computer models you can get into a trap where you think the model is the real world and it is not.”

For the time being, the argument is strictly academic: Nobody has developed a cost-effective way to introduce millions of tons of sulfur into the upper atmosphere. And to pull off a major test would require unprecedented international cooperation, regulation, and oversight—not to mention global political will. Says Keith, such a thing might be considered within a decade—or 75 years. “Who knows,” he tells me. “We might even decide it’s a third rail and never want to go there.”

 

WE'LL BE BLUNT:

We need to start raising significantly more in donations from our online community of readers, especially from those who read Mother Jones regularly but have never decided to pitch in because you figured others always will. We also need long-time and new donors, everyone, to keep showing up for us.

In "It's Not a Crisis. This Is the New Normal," we explain, as matter-of-factly as we can, what exactly our finances look like, how brutal it is to sustain quality journalism right now, what makes Mother Jones different than most of the news out there, and why support from readers is the only thing that keeps us going. Despite the challenges, we're optimistic we can increase the share of online readers who decide to donate—starting with hitting an ambitious $300,000 goal in just three weeks to make sure we can finish our fiscal year break-even in the coming months.

Please learn more about how Mother Jones works and our 47-year history of doing nonprofit journalism that you don't find elsewhere—and help us do it with a donation if you can. We've already cut expenses and hitting our online goal is critical right now.

payment methods

WE'LL BE BLUNT

We need to start raising significantly more in donations from our online community of readers, especially from those who read Mother Jones regularly but have never decided to pitch in because you figured others always will. We also need long-time and new donors, everyone, to keep showing up for us.

In "It's Not a Crisis. This Is the New Normal," we explain, as matter-of-factly as we can, what exactly our finances look like, how brutal it is to sustain quality journalism right now, what makes Mother Jones different than most of the news out there, and why support from readers is the only thing that keeps us going. Despite the challenges, we're optimistic we can increase the share of online readers who decide to donate—starting with hitting an ambitious $300,000 goal in just three weeks to make sure we can finish our fiscal year break-even in the coming months.

Please learn more about how Mother Jones works and our 47-year history of doing nonprofit journalism that you don't elsewhere—and help us do it with a donation if you can. We've already cut expenses and hitting our online goal is critical right now.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate