
The prices of many species of fish have risen in recent months. Coastal pelagic fish, such as mackerel, herring and sardines have risen especially rapidly. Mackerel, once seen as a cheap source of protein, is no longer quite such a ‘bargain’.
From January 2023 to May 2026, the international price index of pelagic fish rose by 69%. In 2025, UK supermarket fresh, chilled smoked and tinned mackerel prices rose by an average of 25%; and over the first part of 2026, some tinned mackerel product lines have increased by as much 55%. In February 2026, Waitrose announced that it would suspend sales of fresh and chilled mackerel and tinned mackerel once current stocks had been cleared. It cited overfishing and sustainability concerns.
Supply and demand
But why have mackerel prices risen so much? The price of fish is determined by demand and supply. So what has changed? The main changes have been on the supply side.
Supply. Most of the world’s supply of mackerel comes from the Northeast Atlantic. These waters have been overfished for many years, thereby depleting the stock of the fish and reducing the amount of mackerel caught.
To arrest the decline and allow stocks to rebuild, the International Council for the Exploration of the Sea (ICES) recommended a quota of 174,357 tonnes for 2026. This would represent a 70% cut from 2025. The main fishing countries – Norway, the UK, the Faroe Islands and Iceland – eventually agreed to a quota of 299,010 tonnes: a cut of 48%. After a series of bilateral agreements between the four countries over access to each other’s waters, this resulted in the following quota shares: UK 30.55%, Norway 26.4%, Faroes 12% and Iceland 10.5%. The remaining 20.55% would be for the EU, Greenland and Russia.
Despite these other countries not being part of the deal, in May 2026 the EU agreed to reduce its catch by 48% too. Russia, however, set its own quota of 67,548 tonnes, which is 22.6% of the total 299,010 quota, above the 20.55% set aside for the EU, Russia and Greenland combined and almost almost five times Russia’s historic quota share! The UK, EU and Iceland responded by agreeing to bar Russian vessels carrying mackerel from entering their ports.
The quotas have added to the decline in supply, even though the aim is to increase supply in the future as stocks are rebuilt. In May this year, the Norwegian catch was down nearly 85% – well below the 48% reduction in the quota.
Demand. Despite higher prices, demand has remained strong. Part of the reason is that demand is relatively inelastic. This is because, despite its increase in price, mackerel remains a relatively cheap fish and thus there is little option to switch to cheaper alternative fish. Indeed, with other fish going up in price, and meat too, some people may even switch to mackerel.
Another reason for strong demand is the growing market outside Europe, especially in southeast Asia, China, South Korea and Japan. In some of these countries, mackerel is seen as a luxury fish and people are prepared to pay higher prices, making demand relatively inelastic but at the other end of the market. In 2025, imports of frozen whole mackerel into the region rose by nearly 9%, despite rising prices.
However, Norwegian exports to the region have been falling, reflecting lower quotas in 2025 and lower still in 2026. This has further exacerbated the rise in price and intensified competition between Asian importers. For example, in July 2026, Korea sent a ‘mackerel envoy’ to Norway and other major exporters to seek to secure additional supplies.
The future
With supply restricted by declining stocks and tighter quotas, and with a price inelastic and growing demand, the high prices of mackerel in all forms look set to last – at least until stocks rebuild and quotas can be relaxed. But, with total quotas well above the level suggested by the ICES, rebuilding could take a long time.
Articles
- Norwegian Mackerel Prices Drive Record Pelagic Values in 2025
The Fishing Daily, Oliver McBride (25/5/26)
- Mackerel prices soar as demand and supply pressures take hold
The Grocer, Charles Elliman (23/1/26)
- Mackerel Prices Have Broken Historical Highs And May See Another Surge in 2026
Caharbor Import and Export Co., Ltd, China (12/1/26)
- Waitrose to suspend mackerel sales due to overfishing concerns
BBC News, Emer Moreau (27/2/26)
- Holy mackerel! The fish Waitrose removed from its shelves
Epigram (University of Bristol student newspaper), Grace Golby (6/6/26)
- Four Northeast Atlantic coastal parties agree on 2026 mackerel quotas, shares; EU left out again
SeafoodSource, Regin Winther Poulsen (17/12/25)
- EU Raises Mackerel Quotas despite Scientific Overfishing Warnings
The Fishing Daily, Oliver McBride (30/3/26)
- High Mackerel Prices Reshape Asian Small Pelagic Trade
The Fishing Daily, Oliver McBride (2/6/26)
- Korea dispatches ‘mackerel envoy’ to Norway as prices spike
Korea JoongAng Daily, Ahn Hyo-Seong (6/7/26)
- Norwegian Mackerel Supply Plunges, Korean Catch Regains Price Edge
Seoul Economic Daily, Nam Yoon-jung (28/6/26)
- Geopolitical unrest, currency effects and quota cuts led to a decline in the value of Norwegian seafood exports in the first half of the year
Norwegian Seafood Council, Press Release (3/7/26)
- Norwegian Seafood Exports: Frozen Mackerel and Herring Prices Surge in Week 26 of 2026
IndexBox (1/7/26)
- New sanctions on Russia following huge unilateral increase in mackerel quota
Fishing News, Steve Mackinson (9/7/26)
Data
Questions
- Draw a supply and demand diagram to illustrate what has happened to mackerel prices.
- What is the effective price elasticity of supply of mackerel?
- Why is demand for mackerel relatively price inelastic in the UK, except when prices rise above a certain level?
- Why is demand for mackerel relatively price inelastic in certain Asian countries, such as Japan and South Korea?
- In which country is demand for mackerel likely to be more income elastic: the UK or Japan?
- Under what circumstances might the price of mackerel in five years’ time be (a) higher than now; (b) lower than now? What will determine which is more likely?
- Should other supermarkets follow Waitrose’s lead in stopping the sale of mackerel?
- What is the ‘tragedy of the commons’? Why is a common resource such as fish in the open seas likely to result in the tragedy?

Andy Burnham is set to become UK Prime Minister on 20 July if no-one else stands to replace Keir Starmer. In a speech on 29 June, he outlined his economic vision. Central to this is devolution, where a greater number of economic decisions would be taken locally rather than by central government. This approach has been dubbed ‘Manchesterism’, in reference to his time as Mayor of Greater Manchester from 2017 to earlier this year. Under his mayoralty, Greater Manchester (GM) achieved faster economic growth than other regions or cities in the UK. From 2017 to 2023, GM’s gross value added grew by an average of 6.6% per annum and the city of Manchester’s by 8.4% – the highest of any city in the UK. The UK average was 4.9% and London’s was 4.6%.
The UK, especially England, is one of the least devolved of the OECD countries. One aspect of this is taxation. The chart shows local taxes and, in the case of federal countries, state/regional/provincial taxes too. (Click here for a PowerPoint.)
Only 4.9% of UK tax revenue is in the form of local taxes (council tax and 50% of business rates) and the amount that can be raised in council tax is capped by the central government. The remainder of UK tax revenue goes to central government in the form of income taxes, social security taxes (national insurance), VAT, excise duties, etc. This compares with an average of 7.1% local taxes and 24.5% local plus regional taxes across the 17 OECD countries shown in the chart.
Andy Burnham plans to shift some of the spending and tax-raising powers from Whitehall to metro mayors and local councils. The aim is to stimulate productivity and economic growth at a regional and local level by tailoring support and incentives to local needs and strengths. Local leaders will be best positioned to understand these needs and strengths and will be able to customise spending and support appropriately.
Examples of the types of greater autonomy over decision making would include:
- Control over adult education budgets to allow them to be tailored to provide training and apprenticeships to meet the skills requirements of existing and emerging industries in the area;
- Forming partnerships with local universities to support research and development that complements regional economic growth;
- Providing greater funding for and control over local transport infrastructure, including roads, buses, trams, trains, etc., with local consultation to make them fit for the local population and businesses;
- Tailoring business incentives to local needs and to the needs of the businesses themselves so as to attract an increase in investment;
- Greatly expanding council house building, which has virtually dried up in recent years, with mayors and/or local authorities empowered to develop local housing strategies, including affordable housing programmes, and to direct housing investment funding to particular housing developments in areas of greatest need.
Andy Burnham has pledged to stick to the government’s two existing fiscal rules:
a) The Stability Rule (Fiscal Mandate): the current (day-to-day) budget must be in balance or surplus. In other words the provision of salaries, public services, state pensions, welfare, etc. must be covered by government revenues (largely taxation). The government should borrow only to fund long-term investment.
b) The Debt Rule (Stock Mandate): each year, public-sector net financial liabilities (PSNFL) must be forecast by the OBR to be falling as a share of GDP compared to the previous year in three years’ time. This acts as a break on the amount of borrowing for long-term investment.
It is likely, therefore, that there will be little extra government money for investment. Rather, the policy involves a redistribution of public-sector investment from central government to mayoral/local authorities.
In theory, such a policy of devolution need not see a redistribution from richer to poorer regions, but that might be part of the policy when the details are published. The UK has a bigger gap in productivity (GDP per worker) between its capital city and other large cities than in do other countries. Birmingham, Sheffield, Leeds, Newcastle, etc., as well as Cardiff, Glasgow, Edinburgh and Belfast, lag further behind London in output per head and economic growth than do other European countries lag behind their capital city. Thus the gap between Paris and Lyon, Toulouse and Marseille is narrower; as is that between Belin and Munich, Hamburg and Frankfurt. It is a similar picture in Spain and Italy. In the USA, some cities, such as San Francisco, outperform Washington DC and New York. A redistribution of government funding from London to the regions could see their incomes rise faster without having too much impact on London, which would still continue to attract large amounts of private investment.
Overall, there would be little increase in government funding. ‘Manchesterism’ is not, therefore, a demand-side policy. It is a supply-side policy – directing funds to areas where, combined with local incentives and local knowledge, the funding could yield greater returns and thereby increase potential GDP.
But this is not to say that there is no effect on aggregate demand. The hope is that devolution along the lines outlined by Andy Burnham will attract increased private investment, thereby increasing actual GDP as well as further increasing potential GDP.
We wait to see the details over the coming weeks.
Articles
- Will Andy Burnham’s devolution plan raise economic growth?
BBC Verify, Ben Chu (29/6/26)
- Burnham’s ‘Manchesterism’ could change the UK, but is not yet a full economic plan
BBC News, Faisal Islam (29/6/26)
- Burnham’s ‘Manchesterism’ got him to No 10 – but will it work for the UK?
BBC News, Faisal Islam (17/7/26)
- Burnham says there is some room for movement on tax
BBC News, Kate Wannel and Joshua Nevett (3/7/26)
- England’s mayors should be given sweeping new powers, says devolution expert
The Guardian, Kiran Stacey (2/7/26)
- What is Andy Burnham’s economic and political blueprint for Britain?
The Guardian, Richard Partington and Jessica Elgot (29/6/26)
- Why Andy Burnham’s radical plan relies on the Treasury being a friend of devolution
The Conversation, Dave Richards and Sam Warner (26/6/26)
- How Andy Burnham may try to give the UK economy a boost in his ‘10‑year plan’
The Conversation, Steve Schifferes (29/6/26)
- Could Andy Burnham let mayors raise more taxes?
House of Commons Research Briefing, Mark Sandford (2/7/26)
- Andy Burnham sets out policy plans in first major speech in PM leadership bid: Legal comments
Browne Jacobson, Dan Robinson (29/6/26)
- What does Andy Burnham think ‘Good Growth’ is?
Centre for Cities, Jess Tulasiewicz (30/6/26)
- Manchester’s digital transformation could be a blueprint for other parts of the UK
The Conversation, Richard Whittle (21/7/26)
Videos
Data
Questions
- Use an aggregate demand and supply diagram (simple or dynamic) to illustrate the effects on real GDP of a successful devolution strategy.
- Find out the details of the last Conservative government’s ‘levelling up’ policy. Was it similar in aims to that of ‘Manchesterism’?
- How could a policy of devolution as outlined by Andy Burnham affect income distribution within regions?
- Find out about the approach to regional policy in the EU. Is it similar to that being advocated by Andy Burnham?
- What is meant by ‘regional multipliers’? Why might they differ from the national multiplier?
The approach towards mergers remains the most controversial area of competition policy. Some argue that policy makers in both the UK and EU have been too easily persuaded by the arguments put forward by firms and so have allowed too many mergers to proceed. Others claim that the opposite is true and that merger policy has prohibited mergers that should have been allowed to proceed. This, then, has a negative impact on investment, innovation, productivity and growth.
In recent years there has been more specific criticism of merger policy in the UK. The government has indicated that it wants the Competition and Markets Authority (CMA) to be less interventionist and take a more pro-growth approach.
In February 2025, in response to this criticism, the CMA launched its new ‘4 Ps’ approach to merger policy: Pace, Predictability, Proportionality and Process. Various changes to the investigation process have been proposed in the past 12 months using this framework.
Pace. The time taken by the CMA to initially assess a merger before deciding whether a Phase 1 investigation is necessary (i.e. the pre-notification procedure) was reduced from 65 to 40 working days. Also, the target to complete straightforward Phase 1 investigations was reduced from 35 to 25 days.
Predictability. The proposed merger guidelines, published in October 2025, provide more detail on (a) what criteria will be used to measure market shares when applying the ‘share of supply test’ (this is where the combined UK market share of two merging businesses is at least 25%, provided one business has a UK turnover of at least £10 million), and (b) the factors that are likely to lead to the competition authorities concluding that one business has gained ‘material influence over another’. Businesses had complained that there was too much uncertainty about the way the share of supply test and material influence were applied. The CMA is also considering greater alignment with other international regulators over decision making rather than its previous policy of acting independently. All these measures should increase the predictability of the investigation process.
Proportionality. Proportionality refers to the objective of addressing any competition issues in merger cases in a way that places the minimum burden on the businesses involved. To improve proportionality, the CMA has indicated that in future cases it will be more willing to use behavioural remedies – requiring firms to take or desist from certain actions. New draft guidelines identify more situations where the use of behavioural remedies may be appropriate. However, they also show that the CMA still views structural remedies (e.g. preventing the merger or requiring firms to demerge or to sell certain assets) as more effective in many situations. Another important measure to improve proportionality is the introduction of a new ‘wait and see’ approach to global mergers. The CMA will now wait to see if the actions taken by other competition authorities in global cases address any concerns in the UK market before deciding whether to launch a review.
Process. To improve the process, the CMA has announced plans to engage with businesses at a much earlier point in the process. For example, it has pledged to share its provisional thinking in the early stages of an investigation by implementing new ‘teach-in’ sessions and having more regular update meetings. Much earlier meetings that focus on possible remedies will also take place. This may make it possible for the CMA to assess the suitability of more complex remedies during a Phase 1 investigation rather than having to wait for a longer and more costly Phase 2 review. Phase 2 reviews will also no longer be managed by panels of independent experts. This role will now be carried out by the internal CMA board.
Some critics argue that the CMA has not fully considered the potential benefits of mergers in many cases. For example, a merger could (a) have procompetitive effects, known as rivalry enhancing efficiencies (REEs) and/or (b) benefits for consumers outside of the relevant market, known as relevant customer benefits (RCBs). In response to this criticism, the CMA is currently reassessing its approach to including evidence on REEs and RCBs.
The CMA is still currently consulting with interested parties about many of these proposed changes. It will be interesting to see what final decisions are made in the next couple of years.
Articles
- CMA consults on proposed changes to its merger remedies approach
CMA Press Release (15/10/25)
- New CMA proposals to drive growth, investment and business confidence
CMA Blog, Sarah Cardell (CMA Chief Executive) (13/2/25)
- Promoting competition and protecting consumers to drive growth and improve household prosperity
CMA Speech, Sarah Cardell (20/11/25)
- Steering the course: how the CMA is responding to the Government’s pro-growth agenda
Macfarlanes (21/2/25)
- 4Ps and 3 themes – An overview of the CMA’s merger remedies review
Hogan Lovells, Angus Coulter, Alice Wallace-Wright, Karman Gordon, and Denise Hotham-Kellner (1/4/25)
- CMA publishes updated guidance on UK merger procedure
Ashurst, Christopher Eberhardt, Emile Abdul-Wahab and Finlay Sadler-Wilson (11/11/25)
- Government ousts UK competition watchdog chair
BBC News, Simon Jack and Charlotte Edwards (21/1/25)
- UK competition watchdog drops Microsoft-OpenAI probe
BBC News, Imran Rahman-Jones (5/3/25)
- Does the government really know what it wants from the CMA?
The Guardian, Nils Pratley (13/2/25)
- This article is more than 9 months old ‘We must avoid a chilling effect’: the CMA chief on the UK’s pro-growth shift
The Guardian, John Collingridge (18/2/25)
- The CMA should be nudged on antitrust, not bullied
The Financial Times, John Gapper (6/2/25)
CMA documentation
Questions
- Of all the mergers considered by the CMA in 2024/25, find out what percentage were formally investigated. How many were blocked from taking place? Do you believe that this indicates that merger policy is too weak or too strong?
- What three criteria must be met for a business arrangement to be classed as a ‘relevant merger situation’ by the CMA?
- Identify some different methods that one business could use to gain material influence over the way another company operates.
- Outline the ‘turnover test’, the ‘share of supply test’ and the ‘hybrid test’.
- Discuss the potential advantages of using behavioural remedies as opposed to structural remedies in merger cases. Why has the CMA still preferred the use of structural remedies in most situations?
This Christmas, more people are considering giving second-hand (or ‘pre-loved’) goods as presents. This allows them to afford better-quality presents and to save money at a time when a large proportion of the population are finding that their finances are stretched. This continues a trend towards buying second-hand products – a trend driven by the rise of various online retailers, such as Vinted and Preloved, and a growing online presence of charity shops, as well as extensive use of established platforms, such as Facebook Marketplace, eBay, Depop, Gumtree and Nextdoor.
Clearly, people gain from buying and selling second-hand items – part of the ‘circular economy’. But what are the implications for gross domestic product (GDP)? After all, GDP is one of the main indicators of the size of an economy, and growth in GDP is probably the most widely-used measure of economic progress. Are second-hand transactions captured in GDP?
If you directly sell your own second-hand items, this does not count towards GDP. There is no new product being made. The items are only counted when they are first produced. Any service you provide to the purchaser (and to yourself) is in a similar category to housework, childcare, DIY and other services that people provide to themselves, household members and friends. But like such services, there is a strong argument that they should be.
Likewise, the environmental benefits (positive externalities) of recycling products, rather than throwing them away or hoarding them, are not counted. In fact, if reusing products causes fewer new products to be made, this would be counted as subtracting from GDP.
If, however, you set up a business by buying and selling second-hand items, the service you provide would contribute towards GDP. What would be counted would the value added to the product – captured through the difference in the purchase and selling prices. In fact, HMRC has warned people that buying and selling second-hand items is taxable, as it counts as self-employment for tax purposes. But it is only this value added that counts. If you buy an item on Vinted, only the value added by Vinted counts towards GDP.
As no production takes place, the purchase of second-hand items adds either nothing to GDP or just the service of a retailer. It is effectively just a transfer of goods and money. If buying second-hand items means that you buy fewer new ones, then that would cause GDP to fall if the response of firms is to produce fewer newer items. However, the person selling the second-hand items will gain revenue, which could be used to buy new items. If that increased production, that would boost GDP. The net effect on GDP of this transfer of goods and money in the second-hand market will be pretty small.
Yet, clearly, the second-hand market provides a welfare gain to both sellers and purchasers – a gain that is likely to grow as the use of second-hand markets increases. At Christmas time, it provides a timely warning of the limitations of using GDP to measure wellbeing.
Articles
- Giving toys another life with another child
Westmorland & Furness Council, News (18/11/25)
- ‘I make £1,000 a week with charity shop side hustle – I couldn’t afford Christmas without it’
Manchester Evening News, Lee Grimsditch and Hannah Cottrell (3/12/25)
- HMRC issues warning to anyone with money-making ‘side hustle’ ahead of Christmas
Manchester Evening News , Ryan Price (12/11/25)
- 12 tips for a low cost Christmas
Rest Less, Melanie Wright (14/11/25)
- I’ve saved over £100 on my girl’s Christmas gifts & got everything on her list including Disney dolls & Hey Dugee toys
The Sun, Becky Pemberton (25/11/25)
- Circular trade is growing, but will second-hand shopping be visible during the Christmas season?
Finnish Commerce Federation, Press Release (27/11/25)
- Shop secondhand, shred your veg and try ‘furoshiki’ wrapping: 14 easy ways to cut Christmas waste
The Guardian, Hannah Rochell (8/12/25)
- 13 Ways to Have a Sustainable Christmas This Year
Circular&Co., Adam Millett (1/12/23)
- The Role of Circular Economy in Driving Economic Growth: Evidence from EU Countries
Sage Open, Vladimir Radivojević, Tamara Rađenović and Jelena Dimovski (14/11/24)
- How to Have a Circular Economy Christmas: Deck the Halls, Sustainably
50 Shades Greener, Kiri Spanowicz (10/12/24)
- Twelve Economic Impacts of Christmas
City-REDI Blog, Birmingham University, Charlotte Hoole (22/12/16)
- Christmas 2025: Christmas Economics Explained
Plus500 (23/11/25)
Questions
- What other items or activities affecting human wellbeing are not counted in GDP?
- Name some goods and services that are produced, and hence are included in GDP, but which can be classed as ‘bads’.
- For what reasons might a country have a high GDP per capita but a poor average level of wellbeing?
- How might GDP figures be adjusted for international comparison purposes?
- Would it be possible to adjust GDP figures to take account of externalities in production (negative and positive)? If so, how?
- Production involves human costs. To what extent does GDP take this into account?
- What is meant by the circular economy? How might you have a ‘circular’ Christmas?
Every year, world leaders gather to find ways of limiting global warming. The latest of these ‘COP’ meetings, COP30, is in Belém, Brazil from 10 to 20 November 2025. COP stands for ‘Conference of the Parties’, the decision-making body of the United Nations Framework Convention on Climate Change (UNFCCC).
Perhaps the best-known of these meetings was in Paris in 2015. This resulted in the Paris Agreement. This is a legally-binding international treaty to limit global warming to well below 2°C and preferably to 1.5°C above pre-industrial levels. This would involve reducing greenhouse gas emissions and/or taking carbon absorbing measures. All UN countries except for Iran, Libya and Yemen are signatories to the agreement.
However, on coming to office in January 2025, President Trump announced that the USA will withdraw from the agreement in January 2026. Instead, he would prioritise fossil fuel production, under the mantra, ‘drill, baby, drill’. Previously he had claimed that global warming is a hoax concocted by China designed to undermine the competitive power of the USA.
Progress in reducing emissions and mitigating climate change
Since 2020, each country has been required to submit its own emissions-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. New NDCs are due this year. As of 12 November, 112 of the 197 countries had submitted a new NDC (including the USA, China, the EU and the UK). These 112 countries account for around 71 per cent of global emissions.
Implementing all new NDCs would reduce global CO2 emissions by between 15 and 25 per cent from current levels by 2035. But this would merely reduce global warming to around 2.6°C above pre-industrial levels. Approximately 35 per cent emissions reductions by 2035 would be required to restrict global warming to 2°C and 55 per cent to restrict it to 1.5°C.
But implementing the Paris Agreement has still had a high degree of success. Without the action taken and being taken over the past 10 years, it is predicted that global temperatures by 2050 would rise by 3–3.5°C.
Rich countries are expected to provide finance to low-income countries. This is required to help such countries adopt green technologies and to adapt to the harmful effects of climate change (e.g. through irrigation schemes and flood defences). At COP29 in Azerbaijan, the ‘Baku Finance Goal’ was agreed. This is an agreement to provide climate finance of $1.3 trillion per year by 2035 to developing countries from all public and private sources.
The subsequent ‘Baku to Belém Roadmap’ provides a set of suggested actions for governments, financial institutions and the private sector to bridge the gap between current climate finance flows and the $1.3 trillion agreed to meet global climate goals. The roadmap is a central focus of the COP30 conference in Belém, with discussions between countries on how to translate the Baku finance goal into concrete, tangible actions and integrate it into formal decisions.
The role of Donald Trump
As well as announcing that the USA will withdraw from the Paris Agreement in January 2026, since coming to office in 2025, President Trump has given billions of dollars of tax cuts to fossil fuel firms and allowed drilling for oil and gas on federal lands. At the same time, he has described renewable energy as ‘a joke’ that will bankrupt countries and has slashed subsidies and tax breaks for solar and wind power, withdrawn permits for wind and solar farms, and cut funding for green energy research.
He wants the USA to be world leader in fossil fuel energy, calling on governments to buy US oil and gas, threatening some countries with tariffs if they do not. Already, Japan, South Korea and several European countries have agreed to buy huge quantities of US oil and liquefied natural gas (LNG). A worry is that other similarly inclined governments, such as Argentina, may roll back on their commitments to a green transition and instead boost their fossil fuel industries.
This gives added urgency to the Belém talks. It is crucial for the rest of the world to stick together in pushing ahead to combat global warming and in adopting and sticking to tough NDCs. It is also crucial for rich countries to support dlow-income countries in adopting climate-friendly investment and in measures to mitigate the effects of global warming.
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.
COP30 and progress in tackling climate change
The USA is not attending COP30 in Brazil. Nor is the Chinese leader, Xi Jinping. However, there are growing opportunities for translating aims into practical policies for specific sectors, such as energy, transport and carbon-intensive industries. These policies may require some degree of government action – taxes, subsidies or regulation – to internalise climate externalities. But increasingly, green alternatives are becoming economically viable without subsidies or with just initial government funding to ‘crowd in’ private investment, which will then attract further private capital as external economies of scale kick in. Increasingly investors will find profitable opportunities in climate-friendly projects.
At the same time, while the USA is moving away from climate-friendly investment (as least for the term of the Trump Presidency), China is moving in the opposite direction, with massive investment in solar panels, wind turbines, EVs and batteries – investment that is bringing down their cost and thereby encouraging their adoption around the world. Such technologies create huge opportunities for low-income countries to provide affordable energy and to create local jobs, both skilled and unskilled. It also helps them achieve much greater energy security by reducing their reliance on fossil fuel imports
Chinese advances in green technology are also providing a stimulus to other countries to invest in renewable industries to prevent Chinese dominance. The danger, however, of Chinese dominance in the renewable sector in high-income countries is that it may encourage them to impose tariffs on Chinese imports of EVs, solar panels, etc. to protect their own industries.
But despite the growing opportunities for profitable adoption of green technologies without government support, there is still much that governments need to do to encourage the process. COP meetings are an important forum for discussing such policies and holding governments to account for meeting or not meeting their targets.
The agreement
The agreement reached at the end of the conference marked relatively small progress. There was agreement to increase finance from developed to developing countries to help them adapt to climate change. This would triple to $120bn per year, up from the previously agreed doubling, but the target date was pushed back to 2035 from the previously agreed 2030.
By the end of the conference, 122 of the 197 countries had submitted a new NDC – still 75 countries short, although others are expected.
The conference also agreed to establish a ‘just transition mechanism (JTM)’ to ‘enhance international cooperation, technical assistance, capacity-building and knowledge-sharing, and enable equitable, inclusive just transitions’. However, this is voluntary and no funding was attached, but it could act as the basis for future funding.
The biggest failure of the conference was probably the lack of agreement on phasing out of fossil fuels. This is not surprising given the opposition of the major oil producers. The hope is that the reduction in costs of renewable energy will drive the process anyway – a process that China is keen to accelerate with its investment in solar power and other renewable energy. One hopeful development, however, was the pledging of more than $9bn to halt deforestation, a major source of global warming. (See the Travers Smith article at the end of the Articles list below for a very useful summary of the outcome.)
Articles
- What is COP30 and why does it matter for the climate?
Chatham House, Anna Åberg (5/9/25)
- COP30 in Brazil: What is at stake for global collaboration on climate and nature?
World Economic Forum, Pim Valdre (5/11/25)
- What is COP30 and why does it matter?
CNN, Laura Paddison (11/11/25)
- Why COP 30 in Brazil Matters for a Thriving Economy and a Safe, Livable Planet
Union of Concerned Scientists (UCS),Rachel Cleetus (7/11/25)
- Nationally Determined Contributions: The Action Plans Behind Global Efforts To Fight the Climate Crisis
Center for American Progress (CAP, Kalina Gibson and Courtney Federico (22/9/25)
- New climate pledges only slightly lower dangerous global warming projections
UN Environment Programme, Press Release (4/11/25)
- COP30: Trump and many leaders are skipping it, so does the summit still have a point?
BBC News, Justin Rowlatt (10/11/25)
- Trump dismisses clean energy as ‘a joke.’ But Americans deserve facts, not fear
USA Today, Mark McNees (23/9/25)
- The surprising countries pulling off stunningly fast clean energy transitions
CNN, Ella Nilsen and Samuel Hart (7/11/25)
Could the world’s biggest polluter be its savior against climate change?
CNN, Simone McCarthy (17/11/25)
- COP 2025: Outlook and Implications for Investors
RankiaPro, Joanna Piwko, Allegra Ianiri, Marie Lassegnore and Jean-Philippe Desmartin (10/11/25)
Post-agreement
- Belém: yet another cop out
Zero Hour, Allan Gray (25/11/25)
- Cop30’s watered-down agreements will do little for an ecosystem at tipping point
The Guardian, Fiona Harvey, Jonathan Watts, Damien Gayle and Damian Carrington (22/11/25)
- COP30: Five key takeaways from a deeply divisive climate summit
BBC News, Justin Rowlatt and Matt McGrath, (25/11/25)
- COP30: What were the key outcomes?
Travers Smith (1/12/25)
Information and Data
Questions
- Summarise the Paris Agreement.
- Summarise the Baku to Belém Roadmap to 1.3T.
- What incentives are there for countries to stick to their NCDs?
- 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 the calculation be changing?
- How might game theory be used to analyse possible international decision making at COP conferences? How might this be affected by the attitudes of the Trump administration?
- Is it in America’s interests to cease investing in green energy and green production methods?