Of all the things that engineers can influence, the climate is probably the most contentious. After all, nobody set out to change the climate; nobody realised that burning fossil fuels could change the climate; and even today, there are people who think that we haven’t changed the climate.
Geoengineering — the idea that we can deliberately change the climate to slow down the effects of climate change, whether on a short-range basis, such as around a major city, or over the entire planet — is a relatively new concept, and is mostly theoretical. It’s also hugely controversial, with environmental campaigners in the forefront of the opposition to it ever becoming a reality. The arguments against range from it being a distraction to the real problem, that of coping with dwindling fossil fuel resources and limiting carbon emissions to prevent buildup of greenhouse gases, to the danger of meddling in complex natural systems that we don’t understand and the likelihood of unexpected outcomes.
These are perfectly understandable and real concerns, particularly the latter; after all, as I said, the whole problem of climate change is one of unexpected outcomes. However, opposition to the UK’s first large-scale geoengineering study seems to be short-sighted.
The study, announced at the British Science Festival in Bradford this week, will see Bristol, Cambridge, Edinburgh and Oxford Universities collaborating with Marshall Aerospace to test the feasibility of releasing particles into the upper atmosphere to absorb some of the sun’s radiation and prevent it from reaching the ground. Called the SPICE (Stratospheric Particle Injection for Climate Engineering) project, the study will involve lifting one end of a hose to a height of 1km using a helium balloon and pumping water through it, to see how both balloon and hose behave. This, the researchers say, will assess the feasibility of using such a technique to spray substances up to 20km into the stratosphere, the altitude that would be necessary for a real cooling effect to be seen.
SPICE will involve no actual geoengineering; however, environmental groups are campaigning against it. Earlier this summer, a group of several dozen environmental organisations lobbied the IPCC to support a moratorium on geo-engineering, partly in reponse to a Royal Society report in 2009 recommending more research.
But as concern grows about some of the visible effects of climate change, such as the retreat of glaciers and the fluctuation in crop yields, it seems imperative to at least gather some information. We know that stratospheric aerosols can affect ground temperatures: we’ve seen this effect after volcanic eruptions, and there was a measureable temperature rise in the week after 9/11, when worldwide flights were grounded and aircraft contrails disappeared.
Should the answer to ‘we don’t have enough information’ be ‘therefore we shouldn’t look’? Or should it be ‘therefore we should get more data’? Scientists and engineers would almost certainly tend to the latter — you can’t make a decision without data. The SPICE team are at pains to say that the debate about their experiment should involve all parties. including environmentalists; however, they’re talking about the debate about their results, not the debate about whether the experiment should take place at all.
It’s certainly a tricky question, and one which we on The Engineer are ambivalent about. Geoengineering is certainly a technology of last resort and one which we hope would never have to be deployed. But we tend not to agree with the slippery slope argument; the fact that we’re researching the technology does not, we’d argue, make it more likely that it would be deployed. SPICE should go ahead, to allow an informed debate to take place.