Aim higher, reach further.

Geoengineering: It’s a Great Idea, It’s a Terrible Idea

As with in-laws, boomerangs, and homing pigeons, there’s just no getting away from geoengineering.


The future’s so bright

The Copenhagen Consensus, an outfit organized by “skeptical environmentalist” Bjorn Lomborg, just released a bunch of new papers seeking to answer the question: Would a technological fix for rising temperatures be cheaper and easier than the cat-herding that makes up today’s global climate-change talks?

The answer is a resounding yes, we don’t know.

That is, on paper at least, climate engineering looks fantastically attractive. For a tiny fraction of the cost of curbing global greenhouse-gas emissions, which lead to global warming, scientists could tinker with the atmosphere and avoid the worst effects of climate change.

Just spraying droplets of sea water to make bigger, whiter clouds, for instance, would reflect enough of the sun’s rays to limit future temperature increases—and it would be ridiculously cheap to do, bringing trillions of dollars of future benefits for a trifling investment today.

That’s the conclusion of “An Analysis of Climate Engineering as a Response to Climate Change,” which strongly recommends more research on ways to deflect solar radiation, whether through whiter clouds or artificially replicating volcanic eruptions, which also send temperatures falling. (Capturing carbon dioxide already in the atmosphere with giant vacuums is too expensive, the paper concludes.)

Sound too good to be true? That’s what other folks at the Copenhagen Consensus thought, too. First, keeping temperatures in check addresses the problem, not the cause—rising carbon levels are still making life miserable for oceans, for example.

Then, there are the “unknown unknowns”: How do you tally the costs and benefits of mucking with the atmoshpere when you don’t know what kind of side effects such experiments might have?

Or as Roger Pielke, Jr. put it, the argument that making fluffier clouds will pay for itself thousands of times over “should be taken with a large dose of salt.” He’s also critical of the unintended consequences of putting a mammoth dollop of sunblock on the whole globe.

And he figures that capturing carbon already in the atmoshphere gets short shrift as a climate-engineering solution. That is, much of that technology—unlike gigantic sunshades—is already fairly well understood. And it can be rolled out gradually and reversed if needed—unlike other geoengineering ideas.

The bottom line is that climate engineering is cropping up more and more as a possible way to buy time while the world figures out just how to clean up its economy and curb emissions. That doesn’t mean it’s a slam dunk by any means.

Photo credit.

Show More Archives

Popular on WSJ