On the day he came to office, President Trump signed a series of executive orders. One of these was to set in motion the process of withdrawing from the UN Paris climate agreement. Section 3(a) of the order reads:
The United States Ambassador to the United Nations shall immediately submit formal written notification of the United States’ withdrawal from the Paris Agreement under the United Nations Framework Convention on Climate Change.
The Paris Agreement is an international treaty on climate change. It was adopted on 12 December 2015 and came into force on 4 November 2016, 30 days after the point was reached when at least 55 countries accounting for at least 55% of global emissions had ratified the treaty.
Currently, all UN countries are signatories to the agreement and only Iran, Libya and Yemen are yet to ratify it. The agreement commits countries to limiting global warming to well under 2°C above pre-industrial levels and preferably to no more than 1.5°C. This would involve reducing greenhouse gas emissions and/or taking carbon absorbing measures.
Since 2020, each country has been required to submit its own emission-reduction targets, known as ‘nationally determined contributions’ (NDCs), and the actions it will take to meet them. Every five years each country must submit a new NDC more ambitious than the last.
Rich countries are expected to provide finance to low-income countries. This is required to help poor countries adopt green technologies and to adapt to the harmful effects of climate change (e.g. through irrigation schemes and flood defences).
Countries set target dates by which emissions would be fully offset by carbon absorption measures (‘net zero’). The UN’s goal is to reach global net zero by 2050. According to the UN Climate Action site:
As of June 2024, 107 countries, responsible for approximately 82 per cent of global greenhouse gas emissions, had adopted net-zero pledges either in law, in a policy document such as an national climate action plan or a long-term strategy, or in an announcement by a high-level government official. More than 9000 companies, over 1000 cities, more than 1000 educational institutions, and over 600 financial institutions have joined the Race to Zero, pledging to take rigorous, immediate action to halve global emissions by 2030.
The Paris Agreement has helped to cut emissions or slow their rate of growth in most countries. Although net zero by 2050 may be unlikely, warming will be less than without the agreement.
The USA and the Paris Agreement
In April 2016 the USA signed the Paris Agreement. As stated above, the Paris Agreement came into effect on 4 November 2016.
President Trump came to office for the first time in January 2017. In June 2017, he signed an executive order in which he announced that the USA would withdraw from the agreement, arguing that it undermined the US economy and put it at a competitive disadvantage. He claimed that global warming is a hoax concocted by China designed to undermine the competitive power of the USA.
However, despite Trump’s intention to withdraw from the agreement, its terms did not allow a country to begin a withdrawal procedure for at least three years after the agreement was ratified (i.e. not before 4 November 2019) and then a year’s notice has to be given. This notice was given on 4 November 2019. In the meantime, the USA had to abide by the terms of the treaty. During this period, US representatives at COP meetings used the opportunity to promote fossil fuels. Withdrawal took place on 1 November 2020, just one day after the presidential election and just over two months before the end of Trump’s first term of office.
On 20 January 2021, his first day in office, President Biden signed an executive order to rejoin the agreement, which took place on 19 February 2021. He committed to cutting total greenhouse gas emissions by at least 50% by 2030. To achieve this, his administration adopted a number of emissions-reducing measures, for example requiring all new passenger vehicles sold after 2035 to be emissions free, giving tax credits for clean electricity generation, providing federal funds for smart agriculture and setting greener appliance and equipment standards.
But, as we have seen, newly elected President Trump for the second time announced that the USA would withdraw from the Paris agreement and would prioritise fossil fuel production, under the mantra, ‘drill, baby, drill’.
The economics of climate change
Climate change is directly caused by market failures. One of the most important of these is that the atmosphere is a common resource: it is not privately owned; it is a global ‘commons’. Individuals and firms use it at a zero price. If the price of any good or service to the user is zero, there is no incentive to economise on its use. Thus for the emitter there are no private costs of using the atmosphere in this way as a ‘dump’ for their emissions and, in a free market, no incentive to reduce the climate costs.
And yet when firms emit greenhouse gases into the atmosphere there are costs to other people. To the extent that they contribute to global warming, part of these costs will be borne by the residents of that country; but a large part will be borne by inhabitants of other countries.
These climate costs are external costs to the firm and are illustrated in the figure. It shows an industry that emits CO2. To keep the analysis simple, assume that it is a perfectly competitive industry with demand and supply given by curves D and S, which are equal to the marginal private benefits (MPB) and marginal private costs (MPC), respectively. There are no externalities on the demand side and hence MPB equals the marginal social cost (MSB). Market equilibrium is at point a, with output at Qpc and price at Ppc. (Click here for a PowerPoint.)
Assume that the emissions create a marginal cost to society equal to MECc. Assume that the MEC increases as output and total emissions increase. The MECc line is thus upward sloping. At the market price of Qpc, these external climate costs are equal to the purple vertical line. When these external climate costs are added to private costs, this gives a marginal social cost given by MSC = MPC + MECc. The gives a socially optimal level of output of the product of Q* at a price of P*, with the optimum point of c.
In other words, other things being equal, the free market overproduces products with climate externalities. If the output is to be reduced to the social optimum of Q*, then the government will need to take measures such as those advocated in the Paris Agreement. These could include imposing taxes on products, such as electricity generated by fossil fuels, or on the emissions themselves. Or green alternatives, such as wind power, could be subsidised.
Alternatively, regulations could be used to cap the production of products creating emissions, or caps on the emissions themselves could be imposed. Emissions permits could be issued or auctioned. Only firms in possession of the permits would be allowed to emit and the permits would cap emissions below free-market levels. These permits could be traded under a cap-and-trade scheme, such as the EU’s Emissions Trading Scheme. Again, such schemes are advocated under the Paris Agreement.
Effect of the USA’s withdrawal from the Paris Agreement
Withdrawal from the Paris Agreement and promoting fossil fuels will increase US emissions. Scientific consensus is that this will have a negative effect on climate change. Only part of these climate costs will be borne by the USA, although the severity of recent fires in California, fanned by strong Santa Ana winds, and more violent hurricanes are two examples of costs of climate change to the USA itself.
A bigger worry is whether the USA’s withdrawal will encourage other countries, such as Argentina, to do likewise. Then the climate costs of US withdrawal will be greater.
But all is not bad news. The transition to green energy is well advanced and the costs of solar and wind power are decreasing. Global investment in clean energy has increased by 60% since 2015. China is investing heavily in renewable energy technology, which is giving it a significant trade advantage. The EU has taken significant actions to promote green energy and technology. Similarly, industrial processes that economise on emissions are developing apace and it is becoming increasingly profitable for private companies to make climate-friendly investments without subsidies. In the USA itself, many Democratic states and local governments, and even some Republican ones, will continue to adopt climate-friendly policies.
In this environment, the Trump administration does not want to fall behind in the development of new technologies and markets. And with Elon Musk having a significant influence on Donald Trump, the USA’s investment in EVs and battery technology is likely to continue. This will help to reduce the price of green energy and transport.
Videos
Articles
- Trump vows to leave Paris climate agreement and ‘drill, baby, drill’
BBC News, Matt McGrath (20/1/25)
- What is the Paris climate agreement and why has Trump withdrawn?
BBC News, Esme Stallard and Mark Poynting (21/1/25)
- Six Trump executive orders to watch
BBC News (21/1/25)
- The real message behind Trump’s withdrawal of US from the Paris climate agreement
Sky News, Tom Clarke (21/1/25)
- Trump signs order to withdraw US from Paris climate agreement for second time
The Guardian, Dharna Noor (20/1/25)
- Explained: how Trump’s day one orders reveal a White House for big oi
The Guardian, Oliver Milman and Dharna Noor (22/1/25)
- Donald Trump can’t stop global climate action. If we stick together, it’s the US that will lose out
The Guardian, Bill Hare (6/11/24)
Trump to pull US from Paris climate agreement: What could this mean for the environment?
ITV News, Martin Stew (21/1/25)
- 10 reasons why US president-elect Donald Trump can’t derail global climate action
The Conversation, Wesley Morgan and Ben Newell (8/11/24)
- Trump has rejected the Paris agreement again, but game theory shows how other countries can still lead by example
The Conversation, Renaud Foucart (27/1/25)
Information
Questions
- Summarise the Paris Agreement.
- Using a diagram similar to that above, illustrate how the free market will produce a sub-optimal amount of solar power because the marginal social benefit exceeds the marginal private benefit.
- How might game theory be used to analyse possible international decision making in the context of US climate policy?
- Is it in America’s interests to cease investing in green energy and green production methods?
- Go through each of the reasons (not specific to Australia) given in The Conversation article linked above why ‘Donald Trump can’t derail global climate action’. To what extent do you agree with each one?
In many countries, train fares at peak times are higher than at off-peak times. This is an example of third-degree price discrimination. Assuming that peak-time travellers generally have a lower price elasticity of demand, the policy allows train companies to increase revenue and profit.
If the sole purpose of ticket sales were to maximise profits, the policy would make sense. Assuming that higher peak-time fares were carefully set, although the number travelling would be somewhat reduced, this would be more than compensated for by the higher revenue per passenger.
But there are external benefits from train travel. Compared with travel by car, there are lower carbon emissions per person travelling. Also, train travel helps to reduce road congestion. To the extent that higher peak-time fares encourage people to travel by car instead, there will be resulting environmental and congestion externalities.
The Scottish experiment with abolishing higher peak-time fares
In October 2023, the Scottish government introduced a pilot scheme abolishing peak-time fares, so that tickets were the same price at any time of the day. The idea was to encourage people, especially commuters, to adopt more sustainable means of transport. Although the price elasticity of demand for commuting is very low, the hope was that the cross-price elasticity between cars and trains would be sufficiently high to encourage many people to switch from driving to taking the train.
One concern with scrapping peak-time fares is that trains would not have the capacity to cope with the extra passengers. Indeed, one of the arguments for higher peak-time fares is to smooth out the flow of passengers during the day, encouraging those with flexibility of when to travel to use the cheaper and less crowded off-peak trains.
This may well apply to certain parts of the UK, but in the case of Scotland it was felt that there would be the capacity to cope with the extra demand at peak time. Also, in a post-COVID world, with more people working flexibly, there was less need for many people to travel at peak times than previously.
Reinstatement of peak-time fares in Scotland
It was with some dismay, therefore, especially by commuters and environmentalists, when the Scottish government decided to end the pilot at the beginning of October 2024 and reinstate peak-time fares – in many cases at nearly double the off-peak rates. For example, the return fare between Glasgow and Edinburgh rose from £16.20 to £31.40 at peak times.
The Scottish government justified the decision by claiming that passenger numbers had risen by only 6.8%, when, to be self-financing, an increase of 10% would have been required. But this begs the question of whether it was necessary to be self-financing when the justification was partly environmental. Also, the 6.8% figure is based on a number of assumptions that could be challenged (see The Conversation article linked below). A longer pilot would have helped to clarify demand.
Other schemes
A number of countries have introduced schemes to encourage greater use of the railways or other forms of public transport. One of these is the flat fare for local journeys. Provided that this is lower than previously, it can encourage people to use public transport and leave their car at home. Also, its simplicity is also likely to be attractive to passengers. For example, in England bus fares are capped at £2. Currently, the scheme is set to run until 31 December 2024.
Another scheme is the subscription model, whereby people pay a flat fee per month (or week or year, or other time period) for train or bus travel or both. Germany, for example, has a flat-rate €49 per month ‘Deutschland-Ticket‘ (rising to €58 per month in January 2025). This ticket provides unlimited access to local and regional public transport in Germany, including trains, buses, trams, metros and ferries (but not long-distance trains). This zero marginal fare cost of a journey encourages passengers to use public transport. The only marginal costs they will face will be ancillary costs, such as getting to and from the train station or bus stop and having to travel at a specific time.
Articles
- Why a pilot scheme removing peak rail fares should have been allowed to go the distance
The Conversation, Rachel Scarfe (8/10/24)
- Return of peak rail fares a costly blow for commuters and climate, Scottish Greens say
Bright Green, Chris Jarvis (6/10/24)
Commuters react to return of peak train fares in Scotland
BBC News (1/10/24)
- Perth peak rail fares to Edinburgh rise by almost 60 percent as pilot scheme ends
Daily Record, Alastair McNeill (4/10/24)
- Ditch peak-time rail fares across UK, campaigners say
iNews, Adam Forrest (30/9/24)
- Train fares reduced by up to 20% in East Yorkshire
Rail Advent, Roger Smith (26/9/24)
- Deutschland-Ticket: Germany’s popular monthly transport pass will soon be more expensive
Euronews, Angela Symons (24/9/24)
- Fare Britannia: a new approach to public transport ticketing for the UK
Greenpeace report, Leo Eyles, Tony Duckenfield and Jim Steer (19/9/24)
- Ministers urged to trial monthly ‘climate card’ in North of England to save rail commuters money and cut emissions
About Manchester, Nigel Barlow (20/9/24)
Questions
- Identify the arguments for and against having higher rail fares at peak times than at off-peak times
- Why might it be a good idea to scrap higher peak-time fares in some parts of a country but not in others?
- Provide a critique of the Scottish government’s arguments for reintroducing higher peak-time fares.
- With reference to The Conversation article, why is it difficult to determine the effect on demand of the Scottish pilot of scrapping peak-time fares?
- What are the arguments for and against the German scheme of having a €49 per month public transport pass for local and regional transport with no further cost per journey? Should it be extended to long-distance trains and coaches?
- In England there is a flat £2 single fare for buses. Would it be a good idea to make bus travel completely free?
A happy New Year for 2024. Let’s hope that the coming year brings some good news amidst all the the gloom of war, squeezed living standards, the effects of climate change and the rise of authoritarian regimes.
One piece of good news is the growth in environmental debt swaps in developing countries. These are known as debt-for-nature swaps (or debt-for-environment swaps or green debt swaps). As Case Study 26.16 in Economics (11th edition) and Case Study 15.19 in Essentials of Economics (9th edition) explain:
A debt-for-nature swap is where debts are cancelled in return for investment in environmental projects, including protecting biodiversity, reducing carbon emissions and mitigating the effect of climate change. There are two types of scheme: bilateral and commercial.
In a bilateral swap, a creditor country agrees to cancel debt in return for the debtor country investing a proportion of the amount in environmental projects. In a commercial swap, the debt owed to banks is sold to an international environmental agency at a substantial discount (or sometimes even given away); the agency then agrees to cancel this debt in return for the country funding the agency to carry out various environmental projects.
The first debt-for-nature swap was made as far back as 1987, when environmental NGO, Conservation International, arranged for Bolivia to be forgiven $650 000 of its debt in exchange for the establishment of three conservation areas bordering the Beni Reserve (see either of the above case studies). In the 1990s and 2000s, debt-for nature swaps became popular with creditors and by 2010, the total debt cancelled through debt-for-nature swaps was just over $1 billion.
However, the popularity waned in the 2010s and with COVID, many developing countries were diverting resources from long-term sustainability and mitigating the effects of climate change to emergency healthcare and relief.
More recently, debt-for-for nature swaps have become popular again.
In May 2023, Ecuador benefited from the biggest debt swap to that point. The agreement saw $1.6bn of its commercial debt refinanced at a discount in exchange for large-scale conservation in and around the Galápagos Islands. At least $12m per year of the money saved will be channelled into conservation in the archipelago, with its unique flora and fauna.
Such projects are set to increase, with potentially significant beneficial effects for biodiversity, climate and the environment generally. At the COP28 summit in December 2023, a task force was set up by a group of multilateral development banks to promote an increase in the size and number of debt-for-nature swaps.
According to the Organisation for Economic Co-operation and Development (OECD), developing economies will need an annual $2.4 trillion of investment in climate action in the coming years. So far, the market for debt-for-nature swaps is set to rise to around $800bn. If they are to make a significant contribution to tackling climate change and loss of biodiversity, they need to be scaled up massively, especially as the cost of servicing debt has risen with higher global interest rates.
Nevertheless, as part of a portfolio of measures to tackle debt, climate change, loss of biodiversity and damage to the environment more generally, they are making an important contribution – a contribution that is set to rise.
Video and Webinar
Articles
Questions
- Identify other types of debt swap and discuss their importance.
- Why are debt-for-nature debt swaps in the interests of debtor countries, creditors and the world generally?
- What is ‘green washing’? How may debt-for-nature swaps be assessed to prevent such green washing?
- Why are many developing countries’ debt burdens skyrocketing?
- Why may a developing country’s solution to its growing debt be detrimental to the environment?
- Assess the Belize debt-swap deal in tackling both its debt and conservation.
The global average temperature for July 2023 was the highest ever recorded and July 3rd was the world’s hottest day on record. We’ve seen scenes of wildfires raging across much of southern Europe, people suffering searing temperatures in south-west USA, southern India and western China, flash floods in South Korea, Japan and eastern USA. These are all directly related to global warming, which is causing weather systems to become more extreme. And as the planet continues to warm, so these problems will intensify.
The Secretary General of the United Nations, Antonio Guterres, in a press conference on 27 July warned that:
Climate change is here. It is terrifying. And it is just the beginning. The era of global warming has ended; the era of global boiling has arrived. The air is unbreathable. The heat is unbearable. And the level of fossil-fuel profits and climate inaction is unacceptable. Leaders must lead. No more hesitancy. No more excuses. No more waiting for others to move first. There is simply no more time for that.
The environmental, human, social and economic impact of global warming is huge, but concentrated on just part of the world’s population. For many, a more variable climate is at worst an inconvenience – at least in the short term. But it is the short term that politicians are most concerned about when seeking to win the next election.
Tackling climate change requires action to reduce carbon emissions now, even though the effects take many years. But one person’s emissions make only a minuscule contribution to global warming. So why not be selfish and carry on driving, flying off on holiday, using a gas boiler and eating large amounts of red meat? This is what many people want to do and governments know it. Many people do not like green policies as they involve sacrifice. Examples include higher fuel prices and restrictions on what you can do. So, despite the visions of fires, floods and destruction, governments are wary about raising fuel taxes, airport duties and charges to use old high-emission cars in cities; wary about raising taxes generally to provide subsidies for sustainable power generation; wary about banning new oil and gas fields that would reduce reliance on imported fuel.
Because the external costs of carbon emissions are so high and global, government action is required to change behaviour. Education can help and scenes of devastation from around the world may change the hearts and minds or some people. Also, the prospect of profits from cleaner and more fuel-efficient technology can help to spur innovation and investment. But to meet net zero targets still requires policies that are unpopular with many people who might be inconvenienced or have to pay higher petrol, energy and food prices, especially at a time when budgets are being squeezed by inflation.
Part of the problem is a distributional one. The people most affected by the cost-of-living crisis and higher interest rates are those on lower incomes and with higher debts. Politicians know that it will be hard to win the votes of such people if they are faced with higher green taxes. As elections approach, politicians are likely to backtrack on many environmental commitments to appeal to such people.
This is beginning to happen in the UK, with the government declaring that it is on the side of the motorist. Indeed, Rishi Sunak has just announced that the government will authorise more than 100 new licenses for new oil and gas wells in the North Sea. This is despite the United Nations, various other international bodies, climate scientists and charities calling for a halt to all licensing and funding of new oil and gas development from new and existing fields. The government argues that increased North Sea production would reduce the reliance on imported oil.
Video
Articles
- July 2023 the Hottest Ever Month on Record, Likely Warmest in ‘Tens of Thousands of Years’
The Wire, Aathira Perinchery (28/7/23)
- Climate threat ‘existential’ says Biden, as world faces hottest July
BBC News, Heather Sharp and Emma Owen (27/7/23)
- UN chief says Earth in ‘era of global boiling’, calls for radical action
Aljazeera (27/7/23)
- Why it’s time to prepare for the worst on climate change
Financial Times, Robert Pindyck (6/7/23)
- The planet heats, the world economy cools – the real global recession is ecological
The Guardian, Larry Elliott (9/7/23)
- Climate change will reshape global supply chains — it can reduce welfare on Earth by 20%: Ivan Rudick
The Economic Times (India), Srijana Mitra Das (30/6/23)
- Rishi Sunak defends granting new North Sea oil and gas licences
BBC News (31/7/23)
- The oil industry has succumbed to a dangerous new climate denialism
The Conversation, Adi Imsirovic (31/7/23)
- Dismay as Rishi Sunak vows to ‘max out’ UK fossil fuel reserves
The Guardian, Severin Carrell, Peter Walker and Helena Horton (31/7/23)
- What are the Conservatives’ green policies – and what could be scrapped
Sky News, Jennifer Scott (31/7/23)
- Rishi Sunak signals he is ready to soften UK green policies
Financial Times, George Parker and Lucy Fisher (24/7/23)
- Green campaigners fear UK policy backlash after ULEZ keeps Uxbridge Tory
Politico, Charlie Cooper and Bethany Dawson (23/7/23)
- Climate policy and economic inequality
VoxEU, Diego Känzig (25/6/23)
- The untapped potential of education in the battle against climate change
VoxEU, Noam Angrist, Kevin Winseck, Harry Anthony Patrinos and Joshua Graff Zivin (14/7/23)
Questions
- In what sense is the environment a ‘public good’? How is the concept of externalities relevant in analysing the private decisions made about the use of a public good?
- How may game theory be used to help understand the difficulties in reaching international agreement about climate change policies?
- What is meant by ‘net zero’? Is carbon capture and storage an acceptable alternative to cutting carbon emissions?
- In what ways could policies to tackle climate change be designed to reduce income inequality rather than increase it?
- What are the arguments for and against banning (a) petrol and diesel cars; (b) gas boilers; (c) fossil-fuel power stations? How much notice should be given if such bans are to be introduced?
- What is meant by ‘nudge theory’? In what ways could people be nudged into making greener decisions?
- What are the arguments for and against granting new licences for North Sea oil and gas drilling? Explain where you feel the balance of the arguments lies.
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.
Report
Videos
Articles
- Climate damage is worsening faster than expected, but there’s still reason for optimism – 4 essential reads on the IPCC report
The Conversation, Stacy Morford at al (20/3/23)
- UN climate scientists are running out of ways to warn us
Vox, Rebecca Leber and Umair Irfan (20/3/23)
- Expert reaction to the AR6 synthesis report, as published by the IPCC
Science Media Centre (20/3/23)
- ‘The climate time-bomb is ticking’: The world is running out of time to avoid catastrophe, new UN report warns
CNN, Laura Paddison (20/3/23)
- UN climate report: Scientists release ‘survival guide’ to avert climate disaster
BBC News, Matt McGrath and Georgina Rannard (20/3/23)
- Five things we’ve learned from UN climate report
BBC News, Matt McGrath (20/3/23)
- Climate change: Can we really take CO2 back out the air?
BBC Future, Jocelyn Timperley (21/3/23)
- Scientists deliver ‘final warning’ on climate crisis: act now or it’s too late
The Guardian, Fiona Harvey (20/3/23)
- From climate change ‘certainty’ to rapid decline: a timeline of IPCC reports
The Guardian, Damian Carrington (20/3/23)
- Humanity at the climate crossroads: highway to hell or a livable future?
The Guardian, Damian Carrington (20/3/23)
IPCC report: Here’s how we can defuse the ‘ticking time bomb’ of climate change
Euronews, Rosie Frost (21/3/23)
- Now or never: One of the biggest climate reports ever shows time is running out
NBC News, Evan Bush and Denise Chow (20/3/23)
Questions
- Why might countries not do ‘everything, everywhere, all at once’ to avert climate change?
- What might an optimist conclude from the ICC report?
- To what extent is climate change an economic problem?
- On a diagram similar to the one above, show how a subsidy could be used to internalise positive externalities.
- How might countries reduce the consumption of fossil fuels in the most efficient way? Are they likely to want to do this? Explain.
- Is a ‘cap-and-trade’ (tradable permits) system (a) an effective means of reducing emissions; (b) an efficient system?