In the run-up to the international climate change conference in Paris in December 2015, there is much debate about what our governments and political institutions should do in order to tackle climate change. Important as this may be, I believe this focus should not obscure the role of individuals. Nonetheless, according to the general perception as well as some accounts in climate ethics, individuals do not appear to be responsible for climate change, or have any agency in tackling it.
I believe this view is mistaken. In this series of posts, I will therefore try to address some pervasive, but (in my view) misleading assumptions regarding individual responsibility for climate change and offer some fresh arguments. (1) The first two posts deal with backward-looking concerns about the identification of individuals as being responsible for climate change, the latter two with forward-looking issues in actually combatting climate change. First, I will debunk the belief that the effects of individual greenhouse gas emissions are insignificant. On this basis, in the second post, I will address the assumption that individual emissions are neither sufficient nor necessary to cause climate change. In the third post, I will advocate direct, unilateral duties to reduce my emissions. Finally, I will give some suggestions regarding what each of us could or should do to tackle climate change.
In this post: Are the effects of individual greenhouse gas emissions truly insignificant?
An individual’s emissions, taken separately, do not appear to have any consequences. Since these emissions do not appear to make any significant difference to climate change or its harmful effects, they seem entirely faultless. However, is it really true that the effects of an individual’s greenhouse gas emissions are insignificant? To answer this question, let me first briefly give an overview of the process of climate change.
The causal process of climate change
The Earth receives energy or heat from the sun, and its surface radiates this energy back into space. However, an important part of this energy does not arrive into space, but is absorbed by greenhouse gases in the atmosphere (such as water vapour, carbon dioxide and methane), warming up the atmosphere and the Earth’s surface. This greenhouse effect is critical to support life.
The greenhouse effect relies on a precarious balance between the sources of greenhouse gases (such as animal and plant respiration, soil decomposition and the exchange of carbon dioxide with the oceans) and the sinks (trees, plants, soil, dissolution in the oceans and the uptake by marine plants and animals) that take up and store greenhouse gases.
Since the beginning of the Industrial Revolution, humanity has started unearthing and burning fossil fuels (carbon stored in the earth in the form of coal, gas and oil), emitting vast amounts of carbon dioxide. Land and ocean sinks are not capable of taking up this massive amount of anthropogenic greenhouse gases. As a consequence, greenhouse gases accumulate in the atmosphere, intensifying the greenhouse effect, and causing global warming.
Increasing global temperatures cause sea level rise and climatic changes (such as changes in precipitation patterns, the increased frequency and intensity of heat waves, drought, floods and storms). These effects in turn exacerbate the risks vulnerable people (now and in the future) are exposed to, increasing mortality, threatening human security, exacerbating the spread of diseases, and increasing existing food and water insecurity.
The effects of individual emissions
By flying an airplane, driving a car, even merely by breathing or consuming food, individuals emit carbon dioxide and other greenhouse gases. Some believe that these individual emissions do not make any difference in the causation of climate change – they appear to have no or insignificant consequences. However, if my emissions do not make any difference, then neither would yours, nor those of 7 billion other individuals. Is climate change then caused by ‘some metaphysically odd emergent entity?’ (2)
Of course it is not. Exactly the emissions of those 7 billion people cause climate change. (3) Therefore, it is tempting to construe climate change as a problem of collective responsibility. Although I do not deny the fact that climate change has become such a large problem because of the accumulation of so many individual greenhouse gas emissions, I do not believe that we first need a complicated philosophical account of collective responsibility in order to derive individual responsibility for climate change harms from it. As our point of departure, we should rather focus on the fact that each greenhouse gas emission has a fully real – albeit exceedingly small – effect in that it increases the risk of climate change harms by a fraction.
Against this, Dale Jamieson and others have objected that it is impossible to trace the effect of a particular greenhouse gas molecule due to the complexity of the causal process of climate change. (4) Climate change is indeed extremely complex, but I cannot see why we would have to trace a particular greenhouse gas molecule all the way in order to judge that its emission increases the risk of climate change harms. For example, it might be true that only some of the greenhouse gases emitted by individuals remain in the atmosphere, absorbing energy and causing global warming. Other emissions are taken up by land and ocean sinks. However, the latter also contribute to climate change because they deplete the capacity of sinks to absorb greenhouse gases. What really matters, is that the amount of greenhouse gases emitted by the individual is not zero, and our knowledge about the physical properties of these gases as well as the processes of global warming and climate change is sufficiently developed to judge that even a miniscule addition of greenhouse gases provides a tiny but real contribution to global warming.
In this context, John Broome estimates an individual emitter’s lifetime contribution to global warming to be half a billionth of a degree, which – he insists – nobody would ever notice. (5) However, whether the effects of individual greenhouse gas emissions are noticeable or not only depends, for example, on the accuracy of our instruments or the limitations of our discerning skills; it is not relevant for normative assessment. The infinitesimal warming resulting from an individual’s emissions might appear too small to be of any consequence, it is not zero, and it increases the risk of climate change harms, if only by a fraction. As Catriona McKinnon eloquently puts it: ‘every token act of emitting greenhouse gases creates risks of serious climate change harms. At the very least, assuming that no such token act creates these risks is unsupported by evidence.’ (6)
In sum, individual greenhouse gas emissions have an exceedingly small but fully real effect in that they increase the risk that vulnerable people suffer from climate change harms. Nonetheless, the fact that this effect is tiny remains problematic for different reasons: it appears that individual emissions are neither sufficient nor necessary to cause climate change. I will address this view in the following post.
Go to the following posts in this series:
(2) A threshold phenomenon?
(3) Unilateral duties to reduce greenhouse gases or promotional duties?
(4) The agency of individuals and households
(1) For the sake of advertisement: my colleagues and I have included some of the arguments in this series in our book Climate change and individual responsibility: Agency, moral disengagement and the motivational gap (Basingstoke: Palgrave MacMillan, 2015).
(2) I owe this phrasing to Avram Hiller: ‘Climate change and individual responsibility’, The Monist 94 (2011), pp. 349-68, at 349.
(3) On the occasion of the publication of the Working Group 1 contribution to the IPCC’s Fifth Assessment Report in 2013, the satirical news website The Onion carried the headline ‘New report finds climate change caused by 7 billion key individuals’.
(4) Dale Jamieson, Reason in a dark time. Why the struggle against climate change failed – and what it means for our future (Oxford: University Press, 2014), pp. 180-1.
(5) John Broome, Climate matters: Ethics in a warming world (New York: W. W. Norton & Company, 2012), p. 75. This figure is based on an unpublished paper (‘Ethics and personal carbon footprints’) by David Frame.
(6) Catriona McKinnon, Climate change and future justice: Precaution, compensation and Triage (Abingdon: Routledge, 2012), p. 103.