Richard Campen asks if it is right to interfere with the Earth's natural systems through geoengineering to avoid climate change
Geoengineering concerns the intentional manipulation of the environment in order to moderate global warming. An example would be the dispersal of sulphate aerosols in the upper atmosphere to reflect sunlight. The methods of geoengineering raise many questions about their likely effectiveness, possible side effects and international governance.
The Guardian reported recently that a small group of climate scientists, with backing from figures such as Bill Gates, were lobbying governments to back experiments that manipulate the climate as a way of avoiding catastrophic global warming. Considering what we know of human impacts on the environment, is it right to further interfere with the Earth’s natural systems?
Many environmentalists are worried about manipulating the climate, even if the goal is to prevent climate change. For example, a British project, Stratospheric Particle Injection for Climate Engineering (SPICE), was postponed in October 2011 due to objections from environmental groups.
The SPICE experiment involved pumping water through a hose to a balloon and dispersing droplets one kilometre above the Earth’s surface. The plan was to eventually pump sulphate aerosols to even higher altitudes to reflect sunlight and cool the planet. The postponement was somewhat lightheartedly reported as “SPICE on ice”. Nevertheless, the experiment is an example of geoengineering research, an area of technology that is set to develop.
The methods of geoengineering fall into two main categories: solar radiation management and carbon dioxide removal. The former might include techniques such as “cloud seeding”, a kind of weather modification, and space sunshades, which divert the Sun’s rays.
Carbon dioxide removal techniques include fertilisation of the sea with iron, to stimulate the growth of algae and the capture of CO₂. Geoengineering methods might prove ineffective, have unknown side effects or even be used as weapons. Also, it is not known how these “technologies” would be governed.
A US task force on climate remediation research has published Geoengineering: A national strategic plan for research on the potential effectiveness, feasibility, and consequences of climate remediation technologies. It follows the UK Royal Society’s 2009 publication Geoengineering the climate: Science, governance and uncertainty.
Both publications propose mitigation and adaptation strategies as priorities, but recognise the uncertainties associated with geoengineering. Both also emphasise the issue of international governance. It is a fact that the technologies exist and there are calls for further research into them, but the social and environmental impacts of most geoengineering methods have not yet been adequately evaluated.
As the dominant species on Earth, human beings have exploited and manipulated the natural environment to get to where we are now. Humans have sought to produce the best outcomes for their species en route to a seven-billion-plus population. Around the globe, humans have drained, irrigated, cleared, levelled and reclaimed land in the name of development.
For many populations these actions have improved overall public health and wellbeing. Some of the general outcomes have been as planned (such as food production), but many have generated new problems, such as desertification, dust storms, flooding and pollution. Each adverse consequence presents health and environmental challenges which are addressed by a combination of short-term measures – for example, dealing with the immediate effects of famine and outbreaks of disease – and longer-term measures, such as legislation for conservation and controlling pollution.
In environmental terms, the track record of the human species is certainly not good; we are seeing a dramatic decline in biodiversity as a result of the increase in the human population and there is general scientific consensus that our exploitation of fossil fuels will cause climate change to some degree.
From an environmental and health perspective, the 2005 Millennium Ecosystem Assessment concluded that the damage to human health caused by environmental changes may be mitigated through strategies that reduce the driving forces of consumption, population increase and inappropriate technology use.
The last item, “use of technology”, should be of great interest to environmentalists and engineers alike, especially in the context of the ongoing debate about the appropriateness of geoengineering options and their potential impact on people and the planet.
We already struggle with the uncertain consequences on human health and wellbeing of exploiting and manipulating the environment, and of climate change. Humans’ abstract reasoning and problem-solving characteristics are leading us inextricably towards the moral and ethical challenges surrounding the new ways in which we can manipulate the environment through geoengineering methods.
A group of scientists have identified nine “planetary boundary processes” as part of a framework for global sustainability, namely: climate change; rate of biodiversity loss; interference with nitrogen and phosphorous cycles; stratospheric ozone depletion; ocean acidification; global freshwater use; change in land use; chemical pollution and atmospheric aerosol loading. They propose these Earth system boundaries provide a safe operating space for humanity.
The question arises as to why human beings think they can or should further interfere with these systems? Especially bearing in mind what we already know about their importance in relation to our health and welfare, and that of the environment.