Climate change is no longer an impending catastrophe to be averted, but an existing condition to be managed. That was the sentiment among scientists at this year's annual meeting for the American Association for the Advancement of Science in San Diego. Just as the world at large seems to be coming to terms with the reality of a warming planet, so too, it seems, science is moving beyond hope of reversal and instead focusing on experimental new measures designed to contain the damage.
Many scientists point to global population growth as the primary cause of change. With more than 50 percent of people living in cities, and a world population soon to hit 7 billion, there's little that can be done. "So far, responding to the challenge [has been an] abject failure," said Braden Allenby, Professor of Engineering and Ethics at Arizona State University.
Countries around the world haven’t been able to agree on the policy changes necessary to stop warming in its tracks. And energy experts warn that most of our alternative energy solutions won’t create enough power to get the world to its goal of zero carbon emissions in 40 years. In fact, even if we did get our emissions down, it wouldn’t be enough – the climate has already changed. The last time global temperatures were below average was February 10, 1993.
So if we’re not going to actually stop global warming, how can we find ways to live with it? That was a question that received quite a bit of attention here in San Diego. Discussions generally at this year's meeting turned to geoengineering – a field of science that would manipulate the earth's climate to keep temperatures down, using such sun-blocking measures as seeding the atmosphere with reflective particles, building large space-based mirrors, or spraying seawater into the atmosphere to increase cloud cover. Though the science may seem far-fetched, scientists are taking it seriously. There have always been background, fringe conversations about how it might work. This year, however, the technology was mentioned in some form or another at nearly every climate-related panel and session at the conference. In many ways, the science once seen as a last resort is starting to look like the only option.
But the implementation of such techniques, which researchers have been pondering since 1946, is at least ten years off. And if it was difficult to convince the public to accept the notion that the earth was warming in the first place, convincing them that the solution lies in an untested science whose results can’t be anticipated may be harder still. In fact, the unknown consequences of climate manipulation can be scary even for geoengineers to contemplate. (Could climate-cooling efforts be so effective that the earth cools too much? Will the effects be reversible? What impact will introducing new particles into the atmosphere have on earth's systems? Nobody is confident about the answers.) What’s more, there are unresolved questions about how we would go about altering the environment, as there are several competing methods on the table, and a lack of consensus about when to begin. Engineers emphasize the need for a global governing body to tackle these issues and to prevent uncoordinated geoengineering attempts that could work against each other, doing more harm than good.
Scientists at the conference also pondered the impact of energy use and earth's growing power needs. Though carbon emissions might not be alone in heating the earth's surface, halting our use of power-generating technologies that release carbon will be essential to controlling warming. Even here, though, there’s concern that our current alternative energy plans – solar, wind, and geothermal power – will not be enough. Eighty percent of the world's energy, after all, still comes from fossil fuels. So scientists are increasingly looking to as-yet commercially untested processes, like capturing the carbon produced by power plants and storing it in deep underground aquifers – or even fusion, to wean ourselves from fossil fuels.
If any of these new technologies are to save us, of course, we’ll need funding and global agreements about implementation. Many of the scientists at the meeting were part of research teams from national labs and universities perfecting methods of geoengineering. And Lawrence Livermore Lab’s National Ignition Facility claims to be closer to fusion every day. If progress continues, Who knows? Measures once dismissed as fringe science could soon be as mainstream as recycling when it comes to saving the earth.