What makes climate change dangerous isn’t just what we know, which is that human activity is warming the planet. It’s also all that we don’t know. How far will temperatures rise, and how fast? What damage will it cause? Will
What makes climate change dangerous isn’t just what we know, which is that human activity is warming the planet. It’s also all that we don’t know. How far will temperatures rise, and how fast? What damage will it cause? Will governments finally confront the problem seriously, and how effective will their efforts be?
The smart response to these uncertainties is to insure against them. That means, first and foremost, shifting away from fossil fuels, ideally by means of a carbon tax. But “geoengineering” technologies that arrest climate change in other ways — by removing greenhouse gases from the atmosphere or by reflecting sunlight back into space — are worth exploring, too.
Geoengineering makes many people uneasy — and for good reason. It involves risks of its own. The most aggressive types of intervention could cause ozone loss, new weather patterns, crop failure and famine; there might be other risks besides. Yet, as a pair of new reports for the National Academy of Sciences argue, this shouldn’t stand in the way of more research.
Geoengineering comes in different forms, with different levels of risk. One approach is to remove carbon from the atmosphere. At the moment, this looks prohibitively expensive, but better technology could lower the cost. The other is adding particles to the upper atmosphere to deflect the sun’s rays. That might be cheaper and faster, but it’s also riskier. It’s similar to what happens when a volcano erupts. That’s how scientists know it has a cooling effect. It’s also why they’re concerned about side effects, such as loss of ozone and changes in weather systems.
In both cases, more research is needed, and it’s an investment worth undertaking. The view that geoengineering should be rejected in principle because it’s wrong to mess with the climate in this way ignores the possibility that drastic remedies might be needed to forestall an eventual climate catastrophe. Geoengineering solutions, despite the drawbacks, might one day look better than the alternative, and by that time it might be too late to deal with global warming more sensibly.
A different objection is that geoengineering is bad tactics because it will make reducing use of fossil fuels seem less urgent. That’s possible, but it doesn’t have to be so. Research into geoengineering acknowledges that climate change is dangerous. It’s a recognition of the problem, and a reminder of its possible scale: It’s hardly a sign of complacency.
Policymakers would need to be clear that dangerous or vastly expensive interventions would be a last resort, and that the best remedy for climate change is relatively cheap and safe: Move away from fossil fuels. But those efforts could fall short — and if they do, geoengineering options would be good to have.
— Bloomberg View
