The current issue of the Royal Society’s journal (Philosophical Transactions) is devoted to geo-engineering. That is, very large scale engineering projects aimed at combatting global warming. For example, one proposal is to release sulphate aerosols in the stratosphere in order to increase the reflectivity of the earth and thus lower the earth’s temperature enough to offset global warming. Another proposal is to increase the reflectivity by producing more cloud over the ocean. This could be achieved with a large fleet of wind powered yachts, blowing a fine mist of salt spray into the air and thus seeding cloud formation. Such proposals offer a serious hope for avoiding most of the damage from significant climate change, and yet they are often rejected by environmentalists (for example see yesterday’s article in the Guardian by Greenpeace’s chief scientist). However, there is a strong case that these environmentalists are mistaken and should be encouraging this research.
The basic case for geo-engineering is obvious. It provides an additional avenue for fighting climate change: one that has the potential to be vastly cheaper and to be much more appealing to the policy makers who are currently dragging their feet on carbon reduction. It is true that it won’t completely negate the effects of climate change: on most of the proposals temperature is kept in check, but the atmosphere will still become more saturated with CO2 and this will still acidify the ocean, causing environmental damage. It is thus not a good replacement for carbon reduction, but it is another much-needed tool in the environmental toolkit.
Environmentalists often respond that we need to be realists: this additional tool will be much more attractive to policy makers and they will use it in preference to carbon reduction. Thus, even if it works, we will be stuck with ocean acidification and other woes. However, I don’t think that this attempt to be realist goes far enough. Consider the many recent articles arguing that we are very near (or indeed beyond) the point of no return for serious climate change. If we want to be realists, we should recognize that there is a high chance that even without geo-engineering possibilities, the governments of the world will fail to prevent serious climate change. If this happens, we will either have to accept severe environmental damage or turn at last to geo-engineering without the benefit of decades of research and testing.
Thus, even the realist response should be to promote current funding in geo-engineering alongside attempts to lower carbon. While doing so, we must simultaneously stress that geo-engineering might not work, and that it would have to undergo extensive safety reviews and testing. However, since there is a high chance that it is the only thing which will prevent major environmental damage, it is a tool that serious environmentalists can’t afford to leave behind. It is true that geo-engineering is ‘just treating the symptoms’, but with the severity of the predicted symptoms and the high chance that no complete cure will be forthcoming, these are symptoms we must prepare to treat.
(See also Oliver Tickell’s recent Guardian article as an example of an environmentalist in favour of geo-engineering research)