In discussions about climate justice, one particular question that receives a lot of attention is that of how to share the global emissions budget (that is, the limited amount of greenhouse gases (GHGs) that can be released into the atmosphere if we are to avoid ‘dangerous’ climate change). A popular proposal here is ‘equal shares’. As suggested by the name, if this solution were adopted the emissions budget would be shared between countries on the basis of population size – resulting in a distribution of emission quotas that is equal per capita. Equal shares is favoured not only by many philosophers, but also a wide range of international organisations (it is the second essential component, for example, of the prominent Contraction and Convergence approach).
I became interested in the equal shares view because it is often put forward with very little argument. Some people seem to think it obvious that this is the best way for parties to the UNFCCC to honour their commitment to deal with climate change on the basis of ‘equity’. But can things really be so simple when this budget must be shared across countries and individuals that differ greatly in terms of their needs, wealth and – arguably – contribution to climate change?
When you look more closely at the arguments that are actually given for equal shares, it turns out that many people claim this to be a fair solution to a global commons problem (for a quick introduction to commons problems, listen here). They argue that distributing emission quotas equates to distributing rights to the atmosphere. The atmosphere, however, is alleged to be a global commons – or shared resource – that no individual has a better claim to than any other. Therefore, rights to this resource – in the form of emission quotas – should be distributed to all human beings globally on an equal per capita basis.
The major problem underlying this argument is its restricted focus on fairly sharing the atmosphere. What many defenders of equal shares neglect to realise is that the atmosphere does not actually act as a sink for carbon dioxide (CO2) – thought to be the most important anthropogenic GHG – which is instead assimilated by the ocean, soils and vegetation. Whilst the argument for equal shares might seem plausible in the case of the ocean – a resource that is also often described as a global commons – it is much harder to carry it over to terrestrial sinks (soils and vegetation), which lie for the most part within state borders. This leaves the equal shares view open to objections from countries like Brazil, which could argue that they should be allocated a higher per capita CO2 allowance on the basis of their possession of a large terrestrial sink (in the form of the Amazon rainforest). Furthermore it seems that Brazil would have backing in international law for such a claim.
The question of whether countries with large terrestrial sinks should have full use rights in these resources – and should therefore be allocated a greater share of the emissions budget – leads us into an enquiry about rights to natural resource that has occupied philosophers for centuries. Roughly speaking, the main parties to this debate are statists – who often deny the existence of significant duties of international justice and attempt to defend full national ownership over natural resources – and cosmopolitans – who hold that justice requires us to treat all human beings equally regardless of their country of birth.
Cosmopolitans often argue that one’s country of birth is a ‘morally arbitrary’ characteristic: a feature like gender or race that shouldn’t be allowed to have a significant influence on your life prospects. They believe it is clearly unfair that a baby lucky enough to be born in Norway will on average have far better life prospects than a baby that happens to be born in Bangladesh. Because of this, cosmopolitans are often opposed to national ownership of natural resources, which they take to be a form of undeserved advantage.
Cosmopolitanism can be used to defend equal per capita emission shares because according to this view, rights to natural resources – whether gold, oil, or carbon sinks – shouldn’t be allocated to whichever state they just happen to be found in.
This cosmopolitan interpretation of fairness has a certain intuitive plausibility – why should claims to valuable natural resources be based on accidents of geography? On the other hand, there are a number of arguments that can be given for taking some people to have a better claim than others to certain carbon sinks. It seems particularly important, for a start, to consider whether indigenous inhabitants of the rainforest should be taken to have a privileged position in decision-making about how this resource is used. We also need to acknowledge that preserving forests will often be costly in terms of missed development opportunities. Why should everybody be able to share equally in the benefits of forest sinks, if it is countries like Brazil or India that must forgo alternative ways of using that land when they choose to conserve? This question is particularly pertinent given that land devoted to rainforest protection cannot be used for alternative – renewable – forms of energy production such as solar or biofuel.
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Commons arguments for equal per capita emission quotas go astray when they claim that the atmosphere is the sole natural resource that assimilates our GHG emissions. Once we recognise this, we should appreciate that the problem of the fair allocation of the global emissions budget cannot be dealt with in isolation, but is instead tied up with broader, difficult questions regarding how the natural world should be used and shared. The answers we give regarding each individual’s claim to use GHG sinks need to be rendered consistent with our judgments regarding the justice of the past and current allocation of rights over other natural resources – resources including fossil fuels and renewables – if we are really to deal with climate change on the basis of equity.
This post was written by Megan Blomfield, a PhD student in the University of Bristol philosophy department. It is based on her paper, published in the latest edition of The Journal of Political Philosophy, titled ‘Global Common Resources and the Just Distribution of Emissions Shares’.
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Megan Blomfield, University of Bristol |