The UN’s Intergovernmental Panel on Climate Change (IPCC) has just published the first part of its latest seven-yearly Assessment Report (AR6) on global warming and its consequences (see video summary). The report was prepared by 234 scientists from 66 countries and endorsed by 195 governments. Its forecasts are stark. World temperatures, already 1.1C above pre-industrial levels, will continue to rise. This will bring further rises in sea levels and more extreme weather conditions with more droughts, floods, wildfires, hurricanes and glacial melting.
The IPCC looked at a number of scenarios with different levels of greenhouse gas emissions. Even in the most optimistic scenarios, where significant steps are taken to cut emissions, global warming is set to reach 1.5C by 2040. If few or no cuts are made, global warming is predicted to reach 4.4C by 2080, the effects of which would be catastrophic.
The articles below go into considerable detail on the different scenarios and their consequences. Here we focus on the economic causes of the crisis and the policies that need to be pursued.
Global success in reducing emissions, although partly dependent on technological developments and their impact on costs, will depend largely on the will of individuals, firms and governments to take action. These actions will be influenced by incentives, economic, social and political.
Economic causes of the climate emergency
The allocation of resources across the world is through a mixture of the market and government intervention, with the mix varying from country to country. But both market and government allocation suffer from a failure to meet social and environmental objectives – and such objectives change over time with the preferences of citizens and with the development of scientific knowledge.
The market fails to achieve a socially efficient use of the environment because large parts of the environment are a common resource (such as the air and the oceans), because production or consumption often generates environmental externalities, because of ignorance of the environmental effects of our actions, and because of a lack of concern for future generations.
Governments fail because of the dominance of short-term objectives, such as winning the next election or appeasing a population which itself has short-term objectives related to the volume of current consumption. Governments are often reluctant to ask people to make sacrifices today for the future – a future when there will be a different government. What is more, government action on the environment which involves sacrifices from their own population, often primarily benefit people in other countries and/or future generations. This makes it harder for governments to get popular backing for such policies.
Economic systems are sub-optimal when there are perverse incentives, such as advertising persuading people to consume more despite its effects on the environment, or subsidies for industries producing negative environmental externalities. But if people can see the effects of global warming affecting their lives today, though fires, floods, droughts, hurricanes, rising sea levels, etc., they are more likely to be willing to take action today or for their governments to do so, even if it involves various sacrifices. Scientists, teachers, journalists and politicians can help to drive changes in public opinion through education and appealing to people’s concern for others and for future generations, including their own descendants.
Policy implications of the IPCC report
At the COP26 meeting in Glasgow in November, countries will gather to make commitments to tackle climate change. The IPCC report is clear: although we are on course for a 1.5C rise in global temperatures by 2040, it is not too late to take action to prevent rises going much higher: to avoid the attendant damage to the planet and changes to weather systems, and the accompanying costs to lives and livelihoods. Carbon neutrality must be reached as soon as possible and this requires strong action now. It is not enough for government to set dates for achieving carbon neutrality, they must adopt policies that immediately begin reducing emissions.
The articles look at various policies that governments can adopt. They also look at actions that can be taken by people and businesses, actions that can be stimulated by government incentives and by social pressures. Examples include:
- A rapid phasing out of fossil fuel power stations. This may require legislation and/or the use of taxes on fossil fuel generation and subsidies for green energy.
- A rapid move to green transport, with investment in charging infrastructure for electric cars, subsidies for electric cars, a ban on new petrol and diesel vehicles in the near future, investment in hydrogen fuel cell technology for lorries and hydrogen production and infrastructure, cycle lanes and various incentives to cycle.
- A rapid shift away from gas for cooking and heating homes and workplaces and a move to ground source heating, solar panels and efficient electric heating combined with battery storage using electricity during the night. These again may require a mix of investment, legislation, taxes and subsidies.
- Improvements in energy efficiency, with better insulation of homes and workplaces.
- Education, public information and discussion in the media and with friends on ways in which people can reduce their carbon emissions. Things we can do include walking and cycling more, getting an electric car and reducing flying, eating less meat and dairy, reducing food waste, stopping using peat as compost, reducing heating in the home and putting on more clothes, installing better insulation and draught proofing, buying more second-hand products, repairing products where possible rather than replacing them, and so on.
- Governments requiring businesses to conduct and publish green audits and providing a range of incentives and regulations for businesses to reduce carbon emissions.
It is easy for governments to produce plans and to make long-term commitments that will fall on future governments to deliver. What is important is that radical measures are taken now. The problem is that governments are likely to face resistance from their supporters and from members of the public and various business who resist facing higher costs now. It is thus important that the pressures on governments to make radical and speedy reductions in emissions are greater than the pressures to do little or nothing and that governments are held to account for their actions and that their actions match their rhetoric.
- Some climate changes now irreversible, says stark UN report
Channel 4 News, Alex Thomson (9/8/21)
- Climate change: IPCC report is ‘code red for humanity’
BBC News, Matt McGrath (10/8/21)
- Climate change: Five things we have learned from the IPCC report
BBC News, Matt McGrath (10/8/21)
- Climate Scientists Reach ‘Unequivocal’ Consensus on Human-Made Warming in Landmark Report
Bloomberg Green, Eric Roston and Akshat Rathi (9/8/21)
- Climate change: Seven key takeaways from the IPCC climate change report
Sky News, Philip Whiteside (10/8/21)
- IPCC report: global emissions must peak by 2025 to keep warming at 1.5°C – we need deeds not words
The Conversation, Keith Baker (9/8/21)
- This is the most sobering report card yet on climate change and Earth’s future. Here’s what you need to know
The Conversation, Pep Canadell, Joelle Gergis, Malte Meinshausen, Mark Hemer and Michael Grose (9/8/21)
- IPCC report: how to make global emissions peak and fall – and what’s stopping us
The Conversation, Matthew Paterson (9/8/21)
- World’s 1.5C goal slipping beyond reach without urgent action, warns landmark IPCC climate report
Independent, Daisy Dunne and Louise Boyle (9/8/21)
- IPCC report: 14 ways to fight the climate crisis after publication of ‘Code Red’ warning
Independent, Harry Cockburn (10/8/21)
- Major climate changes inevitable and irreversible – IPCC’s starkest warning yet
The Guardian, Fiona Harvey (9/8/21)
- Climate scientists have done their bit. Now the pressure is on leaders for COP26.
CNN, Ivana Kottasová and Angela Dewan (10/8/21)
- 21 For 21: The Climate Change Actions Scotland Needs Now
Common Weal, Common Weal Energy Policy Group (9/8/21)
- How to build support for ambitious climate action in 4 steps
The Conversation, Sarah Sharma and Matthew Hoffmann (4/3/21)
- Scientists have finally added world politics to their climate models
Quartz, Michael J Coren (9/8/21)
- Summarise the effects of different levels of global warming as predicted by the IPCC report.
- To what extent is global warming an example of the ‘tragedy of the commons’?
- How could prices be affected by government policy so as to provide an incentive to reduce carbon emissions?
- What incentives could be put in place to encourage people to cut their own individual carbon footprint?
- To what extent is game theory relevant to understanding the difficulties of achieving international action on reducing carbon emissions?
- Identify four different measures that a government could adopt to reduce carbon emissions and assess the likely effectiveness of these measures.
Back in November, when Joe Biden had just been elected, we considered some of his proposed policies to tackle climate change (see A new era for climate change policy?). On 20th January, the day of his inauguration, he signed 17 executive orders overturning a range of policies of the Trump presidency. Further executive orders followed. Some of these related directly to climate change.
The first was to cancel the Keystone XL oil pipeline project. If it had gone ahead, it would have transported 830 000 barrels of oil per day from the Alberta tar sands in Canada to refineries on the Gulf Coast of Texas. It would have involved building a new pipeline from Alberta to Nebraska, where it would have linked to an existing pipeline to Texas. Extracting oil from tar sands is a particularly dirty process, involves cutting down large areas of forest (a carbon sink) and total emissions are around 20% greater per barrel than from conventional crude.
The pipeline would have cut across First Nations land and any spills would have been highly toxic to the local environment. In terms of profitability, returns on tar sands oil extraction and transportation are very low. This is likely to remain the case as oil prices are likely to remain low, with greater global energy efficiency and the switch to renewables.
Critics of Biden’s decision argue that the pipeline project would have created some 5000 to 6000 temporary jobs in the USA during the two-year construction phase. Also they claim that it would have contributed to greater energy security for the USA.
The second executive order was to rejoin the Paris Climate Agreement, a process that will take 30 days. Rejoining will involve commitments to cut greenhouse gas emissions and the adoption of various measures to bring this about. During the election campaign, Biden pledged to achieve economy-wide net-zero emissions no later than 2050. As we saw in the previous blog, under Biden the USA will play a leading role in the November 2021 UN COP26 climate change conference in Glasgow.
At present, the Paris agreement is for countries to aim to reach a peak of greenhouse gas emissions as soon as possible to achieve a climate neutral world by mid-century. Many countries have have made commitments about when they aim to achieve carbon neutrality, although concrete action is much more limited. It is hoped that the COP26 conference will lead to stronger commitments and actions and that the USA under Biden will play a leading part in driving this forward.
In addition, to cancelling the Keystone XL pipeline and rejoining the Paris Agreement, the executive orders reversed more than 100 other decisions with negative environmental effects taken by the Trump administration – many overturning environmental measures introduced by previous administrations, especially the Obama administration.
These orders included reversing the easing of vehicle emissions standards; stopping reductions in the area of two major national monuments (parks) in Utah; enforcing a temporary moratorium on oil and natural gas leases in Alaska’s Arctic National Wildlife Refuge; and re-establishing a working group on the social costs of greenhouse gasses.
Then there will be new measures, such as adopting strict fuel economy standards and investment in clean public transport. But it remains to be seen how far and fast the Biden administration can move to green the US economy. With the desire for bipartisanship and seeking an end to the divisive policies of Trump, there may be limits to what the new President can achieve in terms of new legislation, especially with a Senate divided 50:50 and only the casting vote of the chair (Kamala Harris as Vice-President) being in Democrat hands.
The articles below consider the various green policies and how likely they are to succeed in their objectives.
- Climate change: Biden’s first act sets tone for ambitious approach
BBC News, Matt McGrath (20/1/21)
- Biden nixes Keystone XL permit, halts Arctic refuge leasing
The Hill, Rachel Frazin (20/1/21)
- Biden’s return to Paris pact just a first step for U.S. climate action
Reuters, Megan Rowling (20/1/21)
- Court Decision Lets Biden Set New Emissions Rules To Meet Paris Agreement Climate Goals
Forbes, Allan Marks (20/1/21)
- Biden to ‘hit ground running’ as he rejoins Paris climate accords
The Guardian, Oliver Milman (19/1/21)
- What could a Biden-Harris administration mean for the planet?
Euronews, Marthe de Ferrer (20/1/21)
- Ask a Scientist: What Should the Biden Administration and Congress Do to Address the Climate Crisis?
ecoWatch, Elliott Negin (18/1/21)
- Biden marks Day One with burst of orders reversing Trump policies on climate and health
Science Business, Éanna Kelly (21/1/21)
- What Is the Paris Climate Agreement That Joe Biden Will Rejoin, Why Did Donald Trump Leave?
Newsweek, Kashmira Gander (18/1/21)
- Find out what other environmental policies are being pursued by President Biden and assess their likely effectiveness in achieving their environmental objectives.
- Would policies to reduce carbon emissions necessarily be desirable? How would you assess their desirability?
- When is it best to use the ‘precautionary principle’ when devising environmental policies?
- To what extent is game theory relevant in understanding the difficulties and opportunities of developing internationally agreed policies on carbon reduction?
- If the objective is to tackle global warming, is it better to seek international agreement on limiting the extent of global warming or international agreement on carbon reduction? Explain.
With the election of Joe Biden, the USA will have a president committed to tackling climate change. This is in stark contrast to Donald Trump, who has been publicly sceptical about the link between human action and climate change and has actively supported the coal, oil and gas industries and has rolled back environmental protection legislation and regulation.
What is more, in June 2017, he announced that the USA would withdraw from the UN Paris Accord, the international agreement to cut greenhouse gas emissions so as to limit global warming to ‘well below’ 2°C above pre-industrial levels with efforts to limit it to 1.5°C. The USA’s withdrawal was finalised on 4 November 2020, a day after the US election. Joe Biden, however, pledged to rejoin the accord.
A growing number of countries are pledging to achieve carbon neutrality by mid-century or earlier. The EU is planning to achieve a 55% cut in greenhouse gas emissions by 2030 so as to reach neutrality by 2050. This will involve various taxes, subsidies and public investment. Similar pledges to achieve net zero emissions by 2050 have been made by Japan and South Korea and by 2060 by China. In the UK, legislation was passed requiring the government to reduce the UK’s net emissions 100% relative to 1990 levels by 2050 and thereby achieve net zero emissions.
Constraints on action
Short-termism. One of the problems with setting targets a long time in the future is that they take away the urgency to act now. There are huge time lags between introducing policies to curb carbon emissions and their impact on the climate. The costs of such policies for business and consumers, however, are felt immediately in terms of higher taxes and/or higher prices. Thus politicians may be quick to make long-term pledges but reluctant to take firm measures today. Instead they may prefer to appease various pressure groups, such as motoring organisations, and cut fuel taxes, or, at least, not raise them. Politically, then, it may be easier to focus policy on the short term and just make pledges without action for the future.
Externalities. Various activities that cause carbon emissions, whether directly, such as heavy industry, dairy farming, aviation and shipping, or indirectly, such as oil and coal production, thereby impose environmental costs on society, both at home and abroad. These costs are negative externalities and, by their nature, are not borne by those who produce them. There are often powerful lobbies objecting to any attempt to internalise these externalities through taxes, subsidising green alternatives or regulation. Take the case of the USA. Fossil fuel producers, energy-intensive industries and farmers all claim that green policies will damage their businesses, leading to a loss of profits and jobs. These groups were courted by Donald Trump.
International competition. Countries may well be reluctant to impose green taxes or tough environmental regulation on producers, when competitors abroad do not face such constraints. Indeed, some countries are actively promoting dirty industries as part of their policies to stimulate economic recovery from the Covid-induced recession. Such countries include China, Russia and Turkey. This again was a major argument used in the Trump campaign that US industries should not be hobbled by environmental constraints but should be free to compete.
Misinformation. Politicians, knowing that taking tough environmental measures will be unpopular with large numbers of people, may well downplay the dangers of inaction. Some, such as Trump in America and Bolsonaro in Brazil deliberately appeal to climate change deniers or say that technology will sort things out. This makes it hard for other politicians to promote green policies, knowing that they will face scepticism about the science and the efficacy of their proposed policies.
Biden’s climate change policy
Although it will be difficult to persuade some Americans of the need for tougher policies to tackle climate change, Joe Biden has already made a number of pledges. He has stated that under his administration, the USA will rejoin the Paris Climate Agreement and will play a leading role in the November 2021 UN COP26 climate change conference summit in Glasgow. He has also pledged a Clean Energy Revolution to put the USA on an ‘irreversible path to achieve economy-wide net-zero emissions no later than 2050’.
But readopting the pledges under the Paris Agreement and advocating a clean energy revolution are not enough on their own. Specific measures will need to be taken. So, what can be done that is practical and likely to meet with the approval of the majority of Americans or, at least, of Biden’s supporters?
For a start, he can reintroduce many of the regulations that were overturned by the Trump administration, such as preventing oil and gas companies from flaring methane on public lands. He could introduce funding for the development of green technology. He could require public buildings to use green energy.
According to the Clean Energy Revolution, the US government will develop ‘rigorous new fuel economy standards aimed at ensuring 100% of new sales for light- and medium-duty vehicles will be zero emissions and annual improvements for heavy duty vehicles’.
One of the biggest commitments is to tackle external costs directly by enacting ‘legislation requiring polluters to bear the full cost of their climate pollution’. This may be met with considerable resistance from US corporations. It is thus politically important for Biden to stress the short-term benefits of his policies, not just the long-term ones.
Given the damage done to the economy by the spread of the pandemic, perhaps the main thing that Biden can do to persuade people of the benefits to them of his policies is to focus on green investment and green jobs. Building a green energy infrastructure of wind, solar and hydro and investing in zero-emissions vehicles and charging infrastructure will provide jobs and lead to multiplier effects throughout the economy.
- Trump Administration Removes Scientist in Charge of Assessing Climate Change
The New York Times, Christopher Flavelle, Lisa Friedman and Coral Davenport (9/11/20)
- As U.S. leaves Paris accord, climate policy hangs on election outcome
The Washington Post, Brady Dennis, Juliet Eilperin and Dino Grandoni (5/11/20)
- Where next for US action on Climate Change?
British Foreign Policy Group, Evie Aspinall (11/11/20)
- Media reaction: What Joe Biden’s US election victory means for climate change
Carbon Brief, Josh Gabbatiss (10/11/20)
- Joe Biden: How the president-elect plans to tackle climate change
BBC News, Matt McGrath (10/11/20)
- Biden victory ushers in ‘race to the top’ on climate change
Lexology, Baker McKenzie, David P Hackett and Ilona Millar (13/11/20)
- Climate heroes: the countries pioneering a green future
The Guardian, Jonathan Watts (11/11/20)
- ‘Hypocrites and greenwash’: Greta Thunberg blasts leaders over climate crisis
The Guardian, Damian Carrington (9/11/20)
- Five post-Trump obstacles to a global green recovery
The Guardian, Jonathan Watts (11/11/20)
- Biden’s climate change plans can quickly raise the bar, but can they be transformative?
The Conversation, Edward R Carr (10/11/20)
- Jana Shea/Shutterstock Climate change: Joe Biden could ride a wave of international momentum to break deadlock in US
The Conversation, Richard Beardsworth and Olaf Corry (10/11/20)
- Climate change after COVID-19: Harder to defeat politically, easier to tackle economically
VoxEU, Franziska Funke and David Klenert (17/8/20)
- Identify three specific climate change policies of Joe Biden and assess whether each one is likely to succeed.
- Draw a diagram to illustrate why a free market will lead to over production of a good which produces negative externalities.
- To what extent can education internalise the positive externalities of green consumption and production?
- What was agreed at the Paris climate change conference in December 2015 and what mechanisms were put in place to incentivise countries to meet the targets?
- Will the coronavirus pandemic have had any lasting effects on emissions? Explain.
- How may carbon trading lead to a reduction in carbon emissions? What determines the size of such reductions?
At the annual World Economic Forum (WEF) in Davos, Switzerland, world political and business leaders are meeting to discuss pressing economic issues of the day. This year, one of the key themes is climate change and “how to save the planet”.
The approaches of leaders to the climate crisis, however, differ enormously. At the one extreme there are those who deny that emissions have caused climate change, or who reluctantly acknowledge climate change but think that governments need to do nothing and that technological advances in green energy and transport will be sufficient to curb global warming. This has been the approach of President Trump, President Bolsonaro of Brazil and Prime Minister Scott Morrison of Australia. They may claim to support the general goals of reducing greenhouse gases, but are keen to protect their coal and oil industries and, in the case of Brazil, to continue cutting down the Amazon rain forest to support mining, ranching and the growing of crops.
At his speech at the WEF, President Trump said that he supported the initiative to plant one trillion trees worldwide to act as a carbon sink. However, he gave no details of just what the nature of the support would be. Would there be subsidies or tax breaks, for example, for landowners to plant trees? In the meantime, his administration has relaxed regulations to curb air and water pollution. And he has withdrawn the USA from the Paris climate agreement.
Other leaders, urged on by activists, such as Greta Thunberg, have talked about tougher action to tackle emissions. Countries such as Canada, Norway and the EU countries have adopted a number of initiatives. Policies range from taxing emissions, capping/regulating emissions with penalities for those breaching the limits, tradable permits, subsidising green alternatives, setting local emissions targets with incentives for meeting them, investing in green infrastructure such as roadside charging points for electric vehicles, making environmental education part of a national curriculum, investing in public transport, and so on. But, say, activists, only large-scale measures that truly recognise the scale of the climate emergency will be sufficient.
The year starts with climate being addressed at Davos; it ends with the annual Conference of the Parties (COP26) to the United Nations Framework Convention on Climate Change (UNFCCC). This year it will be in Glasgow. There is much hope pinned on this conference, given the growing realisation of the effects of climate change, from bush fires in Australia, to floods in Indonesia and other parts of southeast Asia, to more extreme hurricanes/typhoons, to rapidly melting glaciers and retreating sea ice, to rising sea levels, to crop failures and the displacement of humans and the destruction of wildlife and habitat.
COP25 in Madrid made little progress; it is hoped that COP26 will be much more successful. Sir David Attenborough has warned that the world faces a ‘climate crisis moment’. He hopes that the world will be ready to take much stronger action at COP26.
But there remains the fundamental economic problem of the tragedy of the commons. As long as the atmosphere and other parts of the environment are free to ‘use’ to pollute, and as long as the costs of doing so are borne largely by people other than the direct polluters, the market will fail to provide a solution. Australia’s bush fires can be directly attributed to climate change and climate change is exacerbated by coal-fired power stations. But Australia’s use of coal as a power source is only a tiny contributor to global climate change. Presumably, the Australian government would rather get a ‘free ride’ off other countries’ policies to cut emissions rather than bearing the economic cost of reducing coal-fired generation itself for little gain in terms of reduced global emissions.
However, people are not entirely selfish. Many are willing to make personal sacrifices to lead a more environmentally sustainable life. Many people, for example, are choosing electricity tariffs that are slightly higher but where the electricity is generated with zero carbon emissions. Firms have shown a readiness to respond to demands from their consumers for more sustainable products.
- Five essential steps to take right now to tackle climate change
World Economic Forum, Robin Pomeroy (17/1/20)
- Davos: Trump decries climate ‘prophets of doom’ with Thunberg in audience
BBC News (21/1/20)
- Greta Thunberg clashes with US treasury secretary in Davos
The Guardian, Graeme Wearden (23/1/20)
- Australia, your country is burning – dangerous climate change is here with you now
The Conversation, Michael E Mann (10/1/20)
- Climate change: What different countries are doing around the globe to tackle the crisis
Independent, Zoe Tidman (20/9/19)
- How we can combat climate change
Washington Post (2/1/19)
- Sir David Attenborough warns of climate ‘crisis moment’
BBC News, David Shukman (16/1/20)
- Climate change: Where we are in seven charts and what you can do to help
BBC News (14/1/20)
- Ten facts about the economics of climate change and climate policy
Brookings, Ryan Nunn, Jimmy O’Donnell, Jay Shambaugh, Lawrence H. Goulder, Charles D Kolstad and Xianling Long (23/10/19)
- The Federal Reserve Considers the Economics of Climate Change in 2020
Lawfare, Rachel Westrate (16/1/20)
- Bernie Sanders’ economic adviser says Australia’s bushfires are a climate change ‘wake-up call’
The Guardian, Ben Butler (7/1/20)
- Carbon pricing: What the research says
Journalist’s Resource, Harvard Kennedy School’s Shorenstein Center, Clark Merrefield (17/1/20)
- European Parliament backs Green Deal
Resource Media, Imogen Benson (17/1/20)
- Tackling climate change
Committee on Climate change
- Tragedy of the Commons: A Drama That Our Planet Is Not Enjoying
Felix, Xiuchen Xu (9/12/19)
- Draw a diagram to show how the external costs of carbon emissions cause a more than socially optimal output of products emitting CO2.
- What is meant by the ‘tragedy of the commons’? Give some environmental examples.
- Discuss possible solutions to the tragedy of the commons.
- Why was COP25 generally regarded as a failure?
- Identify four possible policies that governments could adopt to reduce carbon emissions and discuss their relative advantages and disadvantages.
- Are meetings such as the annual World Economic Forum meetings at Davos of any benefit other than to the politicians attending? Explain.
With the growing recognition of the global climate emergency (see also), attention is being increasingly focused on policies to tackle global warming.
In the October version of its journal, Fiscal Monitor, the IMF argues that carbon taxes can play a major part in meeting the goal of achieving net zero carbon emissions by 2050 or earlier.
As the blog accompanying the journal states:
Global warming has become a clear and present threat. Actions and commitments to date have fallen short. The longer we wait, the greater the loss of life and damage to the world economy. Finance ministers must play a central role to champion and implement fiscal policies to curb climate change. To do so, they should reshape the tax system and fiscal policies to discourage carbon emissions from coal and other polluting fossil fuels.
The effect of a carbon tax on production
The argument is that carbon emissions represent a massive negative externality, where the costs are borne largely by people other than the emitters. Taxes can internalise these externalities. The effect would be to raise the price of carbon-emitting activities and reduce the quantity consumed and hence produced.
The diagram illustrates the argument. 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.
Assessing the benefits of carbon taxes
The diagram shows the direct effect on production of electricity. With widespread carbon taxes, there would be similar direct effects on other industries that emit carbon, and also on consumers, faced with higher fuel prices. In the UK, for example, there are currently higher taxes on high-emissions vehicles than on low-emissions ones.
However, there are other effects of carbon taxes which contribute to the reduction in carbon emissions over the longer term. First, firms will have an incentive to invest in green energy production, such as wind, solar and hydro. Second, it will encourage R&D in green energy technology. Third, consumers will have an incentive to use less electricity by investing in more efficient appliances and home insulation and making an effort to turn off lights, the TV, computers and so on.
People may object to paying more for electricity, gas and motor fuel, but the tax revenues could be invested in cheaper clean public transport, home insulation and public services generally, such as health and education. This could be part of a policy of redistribution, with the tax revenues being spent on alleviating poverty. Alternatively, other taxes could be cut.
The IMF estimates that to restrict global warming to 2°C (a target seen as too modest by many environmentalists), large emitting countries ‘should introduce a carbon tax set to rise quickly to $75 a ton in 2030’.
This would mean household electric bills would go up by 43 per cent cumulatively over the next decade on average – more in countries that still rely heavily on coal in electricity generation, less elsewhere. Gasoline would cost 14 percent more on average.
It gives the example of Sweden, which has a carbon tax of $127 per ton. This has resulted in a 25% reduction in emissions since 1995, while the economy has expanded 75% since then.
Limits of carbon taxes
Although carbon taxes can make a significant contribution to combatting global warming, there are problems with their use.
First, it may be politically popular for governments not to impose them, or raise them, with politicians arguing that they are keen to help ‘struggling motorists’ or poor people ‘struggling to keep their homes warm’. In the UK, successive governments year after year have chosen not to raise road fuel taxes, despite a Fuel Price Escalator (replaced in 2011 by a Fuel Duty Stabiliser) designed to raise fuel taxes each year by more than inflation. Also, governments fear that higher energy prices would raise costs for their country’s industries, thereby damaging exports.
Second, it is difficult to measure the marginal external costs of CO2 emissions, which gives ammunition to those arguing to keep taxes low. In such cases it may be prudent, if politically possible, to set carbon taxes quite high.
Third, they should not be seen as a sufficient policy on their own, but as just part of the solution to global warming. Legislation to prevent high emissions can be another powerful tool to prevent activities that have high carbon emissions. Examples include banning high-emission vehicles; a requirement for coal-fired power stations and carbon emitting factories to install CO2 scrubbers (filters); and tougher planning regulations for factories that emit carbon. Education to encourage people to cut their own personal use of fossil fuels is another powerful means of influencing behaviour.
A cap-and-trade system, such as the European Emissions Trading Scheme would be an alternative means of cutting carbon efficiently. 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.
But, despite being just one possible policy, carbon taxes can make a significant contribution to combatting global warming.
- Fiscal Policies to Curb Climate Change
IMF blog, Vitor Gaspar, Paolo Mauro, Ian Parry and Catherine Pattillo (10/10/19)
- Energy bills will have to rise sharply to avoid climate crisis, says IMF
The Guardian, Larry Elliott (10/10/19)
- Huge global carbon tax hike needed in next 10 years to head off climate disaster, says IMF
Independent, Chris Mooney and Andrew Freedman (11/10/19)
- World urgently needs to quicken steps to reduce global warming – IMF
Reuters, Lindsay Dunsmuir (10/10/19)
- The Case for a Goldilocks Carbon Tax
Forbes, Roger Pielke (13/9/19)
- The world needs a massive carbon tax in just 10 years to limit climate change, IMF says
Washington Post, Chris Mooney and Andrew Freedman (10/10/19)
- People like the idea of a carbon tax – if the money is put to good use
New Scientist, Michael Le Page (18/9/19)
- The IMF thinks carbon taxes will stop the climate crisis. That’s a terrible idea.
The Guardian, Kate Aronoff (12/10/19)
- Firms ignoring climate crisis will go bankrupt, says Mark Carney
The Guardian, Damian Carrington (13/10/19)
- How central banks can tackle climate change
Financial Times, The editorial board (31/10/19)
- World Economic Forum: Climate change action needed to avoid societal ‘collapse’ says minister
The National, UAE, Anna Zacharias (3/11/19)
- Riots and trade wars: Why carbon taxes will not solve climate crisis
Recharge, Leigh Collins (31/10/19) (Part 1)
- The plethora of effective alternatives to carbon pricing
Recharge, Leigh Collins (31/10/19) (Part 2)
- Are these the real reasons why Big Oil wants a carbon tax?
Recharge, Leigh Collins (31/10/19) (Part 3)
- Do we need carbon taxes in an era of cheap renewables?
Recharge, Leigh Collins (31/10/19) (Part 4)
- How to Mitigate Climate Change
IMF Fiscal Monitor, Ian Parry (team leader), Thomas Baunsgaard, William Gbohoui, Raphael Lam, Victor Mylonas, Mehdi Raissi, Alpa Shah and Baoping Shang (October 2019)
- Draw a diagram to show how subsidies can lead to the optimum output of green energy.
- What are the political problems in introducing or raising carbon taxes? Examine possible solutions to these problems
- Choose two policies for reducing carbon emissions other than using carbon taxes? Compare their effectiveness with carbon taxes.
- How is game theory relevant to getting international agreement on cutting greenhouse gas emissions? Why is there likely to be a prisoners’ dilemma problem in reaching and sticking to such agreements? How might the problem of a prisoners’ dilemma be overcome in such circumstances?