The United Nations International Panel on Climate Change (IPCC) has just published its most comprehensive report so far. It finds that ‘human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming’. This has led to widespread and rapid changes in climate and biodiversity and to more extreme weather patterns, such as droughts, floods and hurricanes. What is more, the distribution of these effects is uneven, with communities who have contributed the least to current climate change being disproportionately affected.
At the 2015 COP21 climate change conference in Paris (see also), it was agreed to adopt policies to limit the increase in global temperatures to ‘well below’ 2°C above pre-industrial levels and to make an effort to limit it to 1.5°C. Global temperatures have already risen 1.1°C above 1850–1900 levels and are set to reach 1.5°C in the early 2030s. Every increment of global warming will intensify ‘multiple and concurrent hazards’.
Deep, rapid and sustained reductions in emissions would slow down the rise in global temperatures, but even with such reductions, temperatures will still exceed 1.5°C in the next few years and, even under the best-case scenario, would not fall below 1.5°C again until the end of the 21st century. Under more pessimistic scenarios, global temperatures could rise to 2.7°C above pre-industrial levels by the end of the century under an intermediate greenhouse gas emissions scenario and to 4.4°C under a very high emissions scenario. Anything above 2°C would be likely to have catastrophic effects. The longer countries wait to take action, the greater the rise in global temperatures and hence the greater the damage and the more costly it will be to rectify it.
‘For any given future warming level… projected long-term impacts are up to multiple times higher than currently observed (high confidence). Risks and projected adverse impacts and related losses and damages from climate change escalate with every increment of global warming (very high confidence). Climatic and non-climatic risks will increasingly interact, creating compound and cascading risks that are more complex and difficult to manage (high confidence).’ (Paragraph B2)
But the report is not all ‘doom and gloom’. It is possible to limit global warming to 1.5°C or only a little over by making rapid, deep and, in most cases, immediate greenhouse gas emissions reductions in all sectors and reaching net zero emissions in the early 2050s. Science and technology have the answers – answers that are now much cheaper and more available than back in 2015 when the 1.5°C target was agreed. But what it does require is doing ‘everything, everywhere, all at once’. And that requires political will and the right economic incentives.
The politics and economics of achieving net zero
In terms of the politics, there is general global agreement by governments about the likely effects of climate change. And most governments agree that action needs to be taken. However, there are three key political problems.
The first is that the costs of action will be borne now, while the benefits of action will accrue over a much longer period of time. This links to the second problem – the mismatch between the lives of governments and the long-term effects of climate change. If governments put off doing anything now and merely promise that something will be done in the future, they will not have to take unpopular actions, such as raising taxes on energy, private transport and certain goods or banning various activities. Future governments will have to sort things out, by when, although the problems will be greater, the existing politicians will no longer be in power.
The third problem concerns the distribution of the costs and benefits of action. The major emitters of carbon are the rich countries, while the major sufferers are poor people in countries subject to drought, flooding and rising sea levels. Not surprisingly, who should cut down on emissions and pay for the mitigation necessary in many of the poorer countries is a difficult political issue, which is why it’s much easier to say what needs to be achieved overall than precisely what measures should be taken by which countries.
These problems reflect the fact that many, if not most, of the environmental costs of production and consumption are external costs – costs borne, not by the direct producer or consumer, but by other people at other places and/or in the future.
Nevertheless, the relative costs of moving to greener production and consumption are falling. The costs of renewable energy, including solar power, onshore and offshore wind and hydroelectric power are falling relative to that generated from fossil fuels. At the same time, the take up of electric cars is likely to continue rising as battery technology improves. This does, of course, require an increase in charging infrastructure. Domestic heat pump technology is improving and home insulation methods are becoming more efficient.
Persuading consumers and firms to take account of environmental externalities could in part be achieved by education. It makes it much easier for politicians to take appropriate action now if their populations are on board. There has been increasing awareness over the years of the environmental impact of people’s actions. People have become more willing to take responsibility for the world that future generations will inherit. This is helped both by education in schools and colleges and by frequent items in the media.
But incentives also have a major part to play. To internalise environmental externalities, external costs could be taxed and external benefits subsidised.
The effect of a carbon tax on production
The use of taxes to reduce activities with negative environmental externalities is illustrated in the diagram (click here for a PowerPoint). It takes the case of carbon emissions from coal-fired electricity generation in a large country. To keep the analysis simple, it is assumed that all electricity in the country is generated from coal-fired power stations and that there are many such power stations, making the market perfectly competitive.
It is assumed that all the benefits from electricity production accrue solely to the consumers of electricity (i.e. there are no external benefits from consumption). Marginal private and marginal social benefits of the production of electricity are thus the same (MPB = MSB). The curve slopes downwards because, with a downward-sloping demand for electricity, higher output results in a lower marginal benefit (diminishing marginal utility).
Competitive market forces, with producers and consumers responding only to private costs and benefits, will result in a market equilibrium at point a in the diagram: i.e. where demand equals supply. The market equilibrium price is P0 while the market equilibrium quantity is Q0. However the presence of external costs in production means that MSC > MPC. In other words, MEC = b – a.
The socially optimal output would be Q* where P = MSB = MSC, achieved at the socially optimal price of P*. This is illustrated at point d and clearly shows how external costs of production in a perfectly competitive market result in overproduction: i.e. Q0 > Q*. From society’s point of view, too much electricity is being produced and consumed.
If a carbon tax of d – c is imposed on the electricity producers, it will now be in producers’ interests to produce at Q*, where their new private marginal costs (including tax) equals their marginal private benefit.
But this brings us back to the politics of measures to reduce emissions. People do not like paying higher taxes. In his latest Budget, the UK Chancellor, Jeremy Hunt, decided not to raise fuel duties by the 12p that had been previously planned, despite fuel prices having recently fallen. Meanwhile, charging prices for electric cars have risen.
Other economic measures
A simpler method for dealing with environmental externalities is ban certain activities that omit CO2. For example, in the UK there will be a ban on the sale of new petrol and diesel cars and vans from 2030 (with the exception of some low-emission hybrids until 2035). In the EU there will be a similar ban from 2035. Clearly, such measures are only suitable when there are non-emitting alternatives.
Another alternative is a cap-and-trade system, such as the European Emissions Trading Scheme. It involves setting quotas for emissions and allowing firms which manage to cut emissions to sell their surplus permits to less efficient firms. This puts a price pressure on firms to be more efficient. But the quotas (the ‘cap’) must be sufficiently tight if emissions are going to be cut to desired levels. Nevertheless, it is an efficient way of cutting emissions as it gives a competitive advantage to low-emission producers.
Conclusion
If the problem of global warming is to be limited to 1.5°C, or only very little above, multiple solutions will need to be found and there must be a combination of political will, economic incentives and the mobilisation of scientific and technical know-how. As the Secretary-General of the United Nations, António Guterres, stated in launching the new report:
This report is a clarion call to massively fast-track climate efforts by every country and every sector and on every timeframe. In short, our world needs climate action on all fronts – everything, everywhere, all at once.
In 2015, at the COP21 climate change conference in Paris, an agreement was reached between the 195 countries present. The Paris agreement committed countries to limiting global warming to ‘well below’ 2°C and preferably to no more than 1.5°C. above pre-industrial levels. To do this, a ‘cap-and-trade’ system would be adopted, with countries agreeing to limits to their emissions and then being able to buy emissions credits to exceed these limits from countries which had managed to emit below their limits. However, to implement the agreement, countries would need to adopt a ‘rulebook’ about how the permitted limits would be applied, how governments would measure and report emissions cuts, how the figures would be verified and just how a cap-and-trade system would work.
At the COP24 meeting from 2 to 15 December 2018 in Katowice, Poland, nearly 14 000 delegates from 196 countries discussed the details of a rulebook. Despite some 2800 points of contention and some difficult and heated negotiations, agreement was finally reached. Rules for targeting, measuring and verifying emissions have been accepted. If countries exceed their limits, they must explain why and also how they will meet them in future. Rich countries agreed to provide help to poor countries in curbing their emissions and adapting to rising sea levels, droughts, floods and other climate-induced problems.
But no details have been agreed on the system of carbon trading, thanks to objections from the Brazilian delegates, who felt that insufficient account would be made of their country’s existing promises on not chopping down parts of the Amazon rainforest.
Most seriously, the measures already agreed which would be covered by the rulebook will be insufficient to meet the 2°C, let alone the 1.5°C, target. The majority of the measures are voluntary ‘nationally determined contributions’, which countries are required to submit under the Paris agreement. These, so far, would probably be sufficient to limit global warming to only around 3°C, at which level there would be massive environmental, economic and social consequences.
There was, however, a belief among delegates that further strong international action was required. Indeed, under the Paris agreement, emissions limits to keep global warming to the ‘well below 2°C’ level must be agreed by 2020.
Climate change is a case of severe market failure. A large proportion of the external costs of pollution are borne outside the countries where the emitters are based. This creates a disincentive for countries acting alone to internalise all these externalities through the tax system or charges, or to regulate them toughly. Only by countries taking an international perspective and by acting collectively can the externalities be seen as a fully internal problem.
Even though most governments recognise the nature and scale of the problem, one of the biggest problems they face is in persuading people that it is in their interests to cut carbon emissions – something that may become increasingly difficult with the rise in populism and the realisation that higher fuel and other prices will make people poorer in the short term.
The Conversation, David Farrell and Hamid Homatash (10/12/18)
Questions
To what extent can the atmosphere been seen as a ‘global commons’?
What incentives might be given for business to make ‘green investments’?
To what extent might changes in technology help businesses and consumers to ‘go green’?
Why might international negotiations over tackling climate change result in a prisoner’s dilemma problem? What steps could be taken to tackle the problem?
How would an emissions cap-and-trade system work?
Investigate the Brazilian objections to the proposals for emissions credits. Were the delegates justified in their objections?
What types of initiative could businesses take to tackle ‘supply chain emissions’?
How could countries, such as the USA, be persuaded to reduce their reliance on coal – an industry lauded by President Trump?
Source: Wikimedia Commons: author, Today Testing (https://todaytesting.com)In his Budget on 29 October, the UK Chancellor, Philip Hammond, announced a new type of tax. This is a ‘digital services tax’, which, after consultation, he is planning to introduce in April 2020. The target of the tax is the profits made by major companies providing social media platforms (e.g. Facebook and Twitter), internet marketplaces (e.g. Amazon and eBay) or search engines (such as Alphabet’s Google).
The proposed digital services tax is a 2% tax on the revenues earned by such companies in the UK. It would only apply to large companies, defined as those whose global revenue is at least £500m a year. It is expected to raise around £400m per year.
The EU is considering a similar tax at a rate of 3%. India, Pakistan, South Korea and several other countries are considering introducing digital taxes. Indeed, many countries are arguing for a worldwide agreement on such a tax. The OECD is studying the implications of the possible use of such a tax by its 36 members. If an international agreement on such a tax can be reached, a separate UK tax may not go ahead. As the Chancellor stated in his Budget speech:
In the meantime we will continue to work at the OECD and G20 to seek a globally agreed solution. And if one emerges, we will consider adopting it in place of the UK Digital Services Tax.
The proposed UK tax is a hybrid between direct and indirect taxes. Like corporation tax, a direct tax, its aim is to tax companies’ profits. But, unlike corporation tax, it would be harder for such companies to avoid. Like VAT, an indirect tax, it would be a tax on revenue, but, unlike VAT, it would be an ‘end-stage’ tax rather than a tax on value added at each stage of production. Also, it would not be a simple sales tax on companies as it would be confined to revenue (such as advertising revenue) earned from the use in the UK of search engines, social media platforms and online marketplaces. As the Chancellor said in his speech.
It is important that I emphasise that this is not an online-sales tax on goods ordered over the internet: such a tax would fall on consumers of those goods – and that is not our intention.
There is, however, a political problem for the UK in introducing such a tax. The main companies it would affect are American. It is likely that President Trump would see such taxes as a direct assault on the USA and could well threaten retaliation. As the Accountancy Age article states, ‘Dragging the UK into an acrimonious quarrel with one of its largest trading partners is perhaps not what the Chancellor intends.’ This will be especially so as the UK seeks to build new trading relationships with the USA after Brexit. As the BBC article states, ‘The chancellor will be hoping that an international agreement rides to his rescue before the UK tax has to be imposed.’
After two weeks of negotiations between the 195 countries attending the COP21 climate change conference in Paris, a deal has been reached on tackling climate change. Although the deal still has to be ratified by countries, this is a major step forward in limiting global warming. Before it can formally come into force, it must have been ratified by at least 55 countries, accounting for at least 55% of global greenhouse gas emissions.
The deal goes much further than previous agreements and includes the following:
A limit on the increase in global temperatures to ‘well below’ 2°C above pre-industrial levels and efforts pursued to limit it to 1.5°C.
A recognition that the pledges already made ahead of the conference by 186 countries and incorporated into the agreement are insufficient and will only limit global temperature rise to 2.7°C at best.
Countries to update their emissions reductions commitments every five years – the first being in 2020. Such revised commitments should then be legally binding.
A global ‘stocktake’ in 2023, and every five years thereafter, to monitor countries’ progress in meeting their commitments and to encourage them to make deeper cuts in emissions to reach the 1.5°C goal. This requires a process of measurement and verification of countries’ emissions.
To reach a peak in greenhouse gas emissions as soon as possible and then to begin reducing them and to achieve a balance between sources and sinks of greenhouse gases (i.e. zero net emissions) in the second half of this century.
Developed countries to provide the poorest developing countries with $100bn per year by 2020 to help them reduce emissions. This was agreed in Copenhagen, but will now be continued from 2020 to 2025, and by 2025 a new goal above $100bn per year will be agreed.
The development of market mechanisms that would award tradable credits for green projects and emissions reductions.
A recognition that the ‘loss and damage’ associated with climate-related disasters can be serious for many vulnerable developing countries (such as low-lying island states) and that this may require compensation. However, there is no legal liability on developed countries to provide such compensation.
Perhaps the major achievement at the conference was a universal recognition that the problem of global warming is serious and that action needs to be taken. Mutual self interest was the driving force in reaching the agreement, and although it is less binding on countries than many would have liked, it does mark a significant step forward in tackling climate change.
But why did the conference not go further? Why, if there was general agreement that global warming should be tackled and that global temperature rise should ideally be capped at 1.5°C, was there not a binding agreement on each country to apply this cap?
There are two reasons.
First, it is very difficult to predict the exact relationship, including its timing, between emissions and global temperature rise. Even if you could make limits to emissions binding, you could not make global temperature rise binding.
Second, even if there is general agreement about how much emissions should be reduced, there is no general agreement on the distribution of these reductions. Many countries want to do less themselves and others to do more. More specifically, poor countries want rich countries to do all the cutting while many continue to build more coal-fired power stations to provide the electricity to power economic development. The rich countries want the developing countries, especially the larger ones, such as China, India and Brazil to reduce their emissions, or at least the growth in their emissions.
Then there is the difference between what countries vaguely pledge at a global conference and what they actually do domestically. Many developed countries are keen to take advantage of currently cheap fossil fuels to power economic growth. They are also still investing in alternative sources of fossil fuels, such as through fracking.
As we said in the previous blog, game theory can shed some useful insights into the nature and outcome of climate negotiations. ‘The global optimum may be for a strong agreement, binding on all countries. The Nash equilibrium, however, may be a situation where countries push for their own interests at the expense of others, with the final agreement being much more minimalistic.’
‘Minimalistic’ may be too strong a description of the outcomes of the Paris conference. But they could have been stronger. Nevertheless, judged by the outcomes of previous climate conferences, the deal could still be described as ‘historic’.
The Paris Climate Change Conference (COP21) is under way. At the opening on November 30, 150 Heads of State gathered in Paris, most of whom addressed the conference. With representatives from 195 countries and observers from a range of organisations, the conference is set to last until 11 December. Optimism is relatively high that a legally binding and universal agreement will be reached, with the aim of keeping global warming below 2°C – what is generally regarded as a ‘safe’ limit.
But although it is hoped that a successor to the Kyoto Protocol of 1997 will be put in place, there are many problems in getting so many countries to agree. They may all wish to reduce global warming, but there is disagreement on how it should be achieved and how the burden should be shared between countries.
There are several difficult economic issues in the negotiations. The first is the size and impact of the external costs of emissions. When a country burns fossil fuels, the benefits are almost entirely confined to residents of that county. However, the environmental costs are largely external to that country and only a relatively small fraction is borne by that country and hardly at all by the polluters themselves, unless there is a carbon tax or other form or penalty in place. The problem is that the atmosphere is a common resource and without collective action – national or international – it will be overused.
The second problem is one of distribution. Politicians may agree in principle that a solution is necessary which is equitable between nations, but there is considerable disagreement on what is meant by ‘equitable’ in this context. As the third Guardian article below puts it:
The most important hurdle could be over whether industrialised countries like the US, UK and Japan, which have contributed the most to the historical build-up of emissions, should be obliged to cut more than developing countries. India, on behalf of many poor countries, will argue that there must be “differentiation” between rich and poor; but the US wants targets that are applicable to all. A collision is inevitable.
A third problem is that of uncertainty. Although there is general agreement among scientists that human action is contributing to global warming, there is less agreement on the precise magnitude of the causal relationships. There is also uncertainty over the likely effects of specific emissions reductions. This uncertainty can then be used by governments which are unwilling to commit too much to emissions reductions.
A fourth difficulty arises from the intertemporal distribution of costs and benefits of emissions reductions. The costs are born immediately action is taken. Carbon taxes or charges, or subsidies to renewables, or caps on emissions, all involve higher energy prices and/or higher taxes. The flows of benefits (or lower costs), however, of reduced emissions are not likely to be fully experienced for a very long time. But governments, whether democratic or dictatorships, tend to have a relatively short time horizon, governed by the electoral cycle or the likelihood of staying in power. True, governments may not be solely concerned with power and many politicians may have genuine desires to tackle climate change, but their political survival is still likely to be a major determinant of their actions.
Of course, if there is strong public opinion in favour of action to reduce emissions, governments are likely to respond to this. Indeed, all the expressions of public support for action ahead of the conference from all around the world, do give some hope for a strong agreement at the Paris conference. Nevertheless, there is still widespread scepticism in many countries over the relationship between human action and climate change, and many argue that the costs of policies to tackle climate change exceed the benefits.
Game theory can shed some insights into the difficulties ahead for the negotiators. The global optimum may be for a strong agreement, binding on all countries. The Nash equilibrium, however, may be a situation where countries push for their own interests at the expense of others, with the final agreement being much more minimalistic.
There do, however, seem to be more reasons to be cheerful at this summit that at previous ones. But negotiations are likely to be hard and protracted over the coming days.
The United Nations International Panel on Climate Change (IPCC) has just published its most comprehensive report so far. It finds that ‘human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming’. This has led to widespread and rapid changes in climate and biodiversity and to more extreme weather patterns, such as droughts, floods and hurricanes. What is more, the distribution of these effects is uneven, with communities who have contributed the least to current climate change being disproportionately affected.
Deep, rapid and sustained reductions in emissions would slow down the rise in global temperatures, but even with such reductions, temperatures will still exceed 1.5°C in the next few years and, even under the best-case scenario, would not fall below 1.5°C again until the end of the 21st century. Under more pessimistic scenarios, global temperatures could rise to 2.7°C above pre-industrial levels by the end of the century under an intermediate greenhouse gas emissions scenario and to 4.4°C under a very high emissions scenario. Anything above 2°C would be likely to have catastrophic effects. The longer countries wait to take action, the greater the rise in global temperatures and hence the greater the damage and the more costly it will be to rectify it.
The third problem concerns the distribution of the costs and benefits of action. The major emitters of carbon are the rich countries, while the major sufferers are poor people in countries subject to drought, flooding and rising sea levels. Not surprisingly, who should cut down on emissions and pay for the mitigation necessary in many of the poorer countries is a difficult political issue, which is why it’s much easier to say what needs to be achieved overall than precisely what measures should be taken by which countries.
The use of taxes to reduce activities with negative environmental externalities is illustrated in the diagram (click here for a PowerPoint). It takes the case of carbon emissions from coal-fired electricity generation in a large country. To keep the analysis simple, it is assumed that all electricity in the country is generated from coal-fired power stations and that there are many such power stations, making the market perfectly competitive.
A simpler method for dealing with environmental externalities is ban certain activities that omit CO2. For example, in the UK there will be a ban on the sale of new petrol and diesel cars and vans from 2030 (with the exception of some low-emission hybrids until 2035). In the EU there will be a similar ban from 2035. Clearly, such measures are only suitable when there are non-emitting alternatives.
Address by UN Secretary General, António Guterres (Transcript)
In 2015, at the 
But no details have been agreed on the system of carbon trading, thanks to objections from the Brazilian delegates, who felt that insufficient account would be made of their country’s existing promises on not chopping down parts of the Amazon rainforest. 
The proposed digital services tax is a 2% tax on the revenues earned by such companies in the UK. It would only apply to large companies, defined as those whose global revenue is at least £500m a year. It is expected to raise around £400m per year.
