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?
Last week was a rough week for Britain. The “Beast from the East” and storm Emma swept through the country, bringing with them unusually heavy snowfall, which resulted in severe disruption across nearly all parts of the country. Some recent estimates put the cost of these extreme weather conditions at up to £1 billion per day. The construction industry suffering the biggest hit as work came to a halt for the best part of the week. Losses for the industry were estimated to be up to £2 billion.
Closed restaurants, empty shops and severely disrupted transport networks were all part of the effect that this extreme weather had on the overall economy. According to Howard Archer, chief economic adviser of the EY ITEM Club (a UK forecasting group):
It is possible that the severe weather [of the last few days] could lead to GDP growth being reduced by 0.1 percentage point in Q1 2018 and possibly 0.2 percentage points if the severe weather persist.
Source: Jahn (2015), Figure 2
As the occurrence of freak weather increases across the globe due to climate change, so does the economic cost of these events. The figure above shows the estimated costs of extreme weather events in the USA between 1980 and 2012 and it is reproduced from Jahn (see link below), who also fits a quadratic trend to show that these costs have been increasing over time. He goes on to characterise the impact of different types of extreme weather (including cold waves, heat waves, storms and others) on different sectors of the local economy – ranging from tourism and agriculture, to housing and the insurance sector.
Linnenluecke et al (linked below) argue that extreme weather caused by climate change could influence the decision of firms on where to locate and could lead to a reshuffle of economic activity across the world and have important policy implications. As the authors explain:
Climate change-related relocation has been given consideration in policy-oriented discussions, but not in management decisions. The effects of climate change and extreme weather events have been considered as peripheral or as a risk factor, but not as a determining factor in firm relocation processes…. This paper therefore [provides] insights for understanding how firms can enhance strategic decision-making in light of understanding and assessing their vulnerability as well as likely impacts that climate change may have on relocation decisions.
The likelihood and associated costs of extreme weather events could therefore become an increasingly important matter for discussion amongst economists and policy makers. Such weather events are likely to have profound economic implications for the world.
With first Houston, then several Caribbean islands and Florida suffering dreadful flooding and destruction from Hurricanes Harvey and Irma, many are questioning whether more should be spent on flood prevention and reducing greenhouse gas emissions. Economists would normally argue that such questions are answered by conducting a cost–benefit analysis.
However, even if the size of the costs and benefits of such policies could be measured, this would not be enough to give the answer. Whether such spending is justified would depend on the social rate of discount. But what the rate should be in cost-benefit analyses is a highly contested issue, especially when the benefits occur a long time in the future.
I you ask the question today, ‘should more have been spent on flood prevention in Houston and Miami?’, the answer would almost certainly be yes, even if the decision had to have been taken many years ago, given the time it takes to plan and construct such defences. But if you asked people, say, 15 years ago whether such expenditure should be undertaken, many would have said no, given that the protection would be provided quite a long time in the future. Also many people back then would doubt that the defences would be necessary and many would not be planning to live there indefinitely.
This is the familiar problem of people valuing costs and benefits in the future less than costs and benefits occurring today. To account for this, costs and benefits in the future are discounted by an annual rate to reduce them to a present value.
But with costs and benefits occurring a long time in the future, especially from measures to reduce carbon emissions, the present value is very sensitive to the rate of discount chosen. But choosing the rate of discount is fraught with difficulties.
Some argue that a social rate of discount should be similar to long-term market rates. But market rates reflect only the current generation’s private preferences. They do not reflect the costs and benefits to future generations. A social rate of discount that did take their interests into account would be much lower and could even be argued to be zero – or negative with a growing population.
Against this, however, has to be set the possibility that future generations will be richer than the current one and will therefore value a dollar (or any other currency) less than today’s generation.
However, it is also likely, if the trend of recent decades is to continue, that economic growth will be largely confined to the rich and that the poor will be little better off, if at all. And it is the poor who often suffer the most from natural disasters. Just look, for example, at the much higher personal devastation suffered from hurricane Irma by the poor on many Caribbean islands compared with those in comparatively wealthy Florida.
A low or zero discount rate would make many environmental projects socially profitable, even though they would not be with a higher rate. The choice of rate is thus crucial to the welfare of future generations who are likely to bear the brunt of climate change.
But just how should the social rate of discount be chosen? The following two articles explore the issue.
Why does the choice of a lower rate of social discount imply a more aggressive climate policy?
How is the distribution of the benefits and costs of measures to reduce carbon emissions between rich and poor relevant in choosing the social rate of discount of such measures?
How is the distribution of the benefits of such measures between current and future generations relevant in choosing the rate?
How is uncertainty about the magnitude of the costs and benefits relevant in choosing the rate?
What is the difference between Stern’s and Nordhaus’ analyses of the choice of social discount rate?
Explain and discuss the ‘mortality-based approach’ to estimating social discount rates.
What are the arguments ‘for economists analysing climate change through the lens of minimising risk, rather than maximizing utility’?
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.
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.
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. 
