Tag: common resources


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.

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Data

  • Dashboards
  • European Market Observatory for Fisheries and Aquaculture Products (EUMOFA)

Questions

  1. Draw a supply and demand diagram to illustrate what has happened to mackerel prices.
  2. What is the effective price elasticity of supply of mackerel?
  3. Why is demand for mackerel relatively price inelastic in the UK, except when prices rise above a certain level?
  4. Why is demand for mackerel relatively price inelastic in certain Asian countries, such as Japan and South Korea?
  5. In which country is demand for mackerel likely to be more income elastic: the UK or Japan?
  6. 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?
  7. Should other supermarkets follow Waitrose’s lead in stopping the sale of mackerel?
  8. 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?


Politicians, business leaders, climate scientists, interest groups and journalists from across the world have been meeting in Dubai at the COP28 climate summit (the 28th annual meeting of the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC)). The meeting comes at a time when various climate tipping points are being reached or approached – some bad, but some good. Understanding these tipping points and their implications for society and policy requires understanding not only the science, but also the various economic incentives affecting individuals, businesses, politicians and societies.

Tipping points

A recent report (see first reference in articles section below) identified various climate tipping points. These are when global temperatures rise to a point where various domino effects occur. These are adverse changes to the environment that gather pace and have major effects on ecosystems and the ability to grow food and support populations. These, in turn, will have large effects on economies, migration and political stability.

According to the report, five tipping points are imminent with the current degree of global warming (1.2oC). These are:

  • Melting of the Greenland ice sheet;
  • Melting of the West Antarctic ice sheet;
  • Death of warm-water coral reefs;
  • Collapse of the North Atlantic Subpolar Gyre circulation, which helps to drive the warm current that benefits Western Europe;
  • Widespread rapid thawing of permafrost, where tundra without snow cover rapidly absorbs heat and releases methane (a much more powerful source of global warming than CO2).

With global warming of 1.5oC, three more tipping points are likely: the destruction of seagrass meadows, mangrove swamps and the southern part of the boreal forests that cover much of northern Eurasia. As the temperature warms further, other tipping points can interact in ways that drive one another, resulting in tipping ‘cascades’.

But the report also strikes an optimistic note, arguing that positive tipping points are also possible, which will help to slow global warming in the near future and possibly reverse it further in the future.


The most obvious one is in renewable energy. Renewable power generation in many countries is now cheaper than generation from fossil fuels. Indeed, in 2022, over 80% of new electricity generation was from solar and wind. And as it becomes cheaper, so this will drive investment in new renewable plants, including in small-scale production suitable for use in developing countries in parts not connected to a grid. In the vehicle sector, improved battery technology, the growth in charging infrastructure and cheaper renewable sources of electricity are creating a tipping point in EV take-up.

Positive tipping points can take place as a result of changing attitudes, such as moving away from a meat-intensive diet, avoiding food waste, greater use of recycling and a growth in second-hand markets.

But these positive tipping points are so far not strong enough or quick enough. Part of the problem is with economic incentives in market systems and part is with political systems.

Market failures

Economic decisions around the world of both individuals and firms are made largely within a market environment. But the market fails to take into account the full climate costs and benefits of such decisions. There are various reasons why.

Externalities. Both the production and consumption of many goods, especially energy and transport, but also much of agriculture and manufacturing, involve the production of CO2. But the costs of the resulting global warming are not born directly by the producer or consumer. Instead they are external costs born by society worldwide – with some countries and individuals bearing a higher cost than others. The result is an overproduction or consumption of such goods from the point of view of the world.

The environment as a common resource. The air, the seas and many other parts of the environment are not privately owned. They are a global ‘commons’. As such, it is extremely difficult to exclude non-payers from consuming the benefits they provide. Because of this property of ‘non-excludability’, it is often possible to consume the benefits of the environment 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. In the case of the atmosphere as a ‘dump’ for greenhouse gases, this results in its overuse. Many parts of the environment, however, including the atmosphere, are scarce: there is rivalry in their use. As people increase their use of the atmosphere as a dump for carbon, so the resulting global warming adversely affects the lives of others. This is an example of the tragedy of the commons – where a free resource (such as common land) is overused.

Inter-generational problems. The effect of the growth in carbon emissions is long term, whereas the benefits are immediate. Thus consumers and firms are frequently prepared to continue with various practices, such as driving, flying and using fossil fuels for production, and leave future generations to worry about their environmental consequences. The problem, then, is a reflection of the importance that people attach to the present relative to the future.

Ignorance. People may be contributing to global warming without realising it. They may be unaware of which of the goods they buy involve the release of carbon in their production or how much carbon they release when consumed.

Political failures

Governments, whether democratic or dictatorships, face incentives not to reduce carbon emissions – or to minimise their reduction, especially if they are oil producing countries. Reducing carbon involves short-term costs to consumers and this can make them unpopular. It could cost them the next election or, in the case of dictatorships, make them vulnerable to overthrow. What is more, the oil, coal and gas industries have a vested interest in continuing the use of fossil fuels. Such industries wield considerable political power.

Even if governments want the world to reduce carbon emissions, they would rather that the cost of doing so is born less by their own country and more by other countries. This creates a prisoner’s dilemma, where the optimum may be for a large global reduction in carbon emissions, but the optimum is not achieved because countries individually are only prepared to reduce a little, expecting other countries to reduce more. Getting a deal that is deemed ‘fair’ by all countries is very difficult. An example is where developing countries, may feel that it is fair that the bulk of any cuts, if not all of them, should be made by developed countries, while developed countries feel that fixed percentage cuts should be made by all countries.

Policy options

If the goal is to tackle climate change, then the means is to reduce the amount of carbon in the atmosphere (or at the least to stop its increase – the net zero target). There are two possibilities here. The first is to reduce the amount of carbon emissions. The second is to use carbon capture and storage or carbon sequestration (e.g. through increased forestation).

In terms of reducing carbon emissions, the key is reducing the consumption of carbon-producing activities and products that involve emissions in their production. This can be achieved through taxes on such products and/or subsidies on green alternatives (see the blog ‘Are carbon taxes a solution to the climate emergency?‘). Alternatively carbon-intensive consumption can be banned or phased out by law. For example, the purchase of new petrol or diesel cars cold be banned beyond a certain date. Or some combination of taxation and regulation can be used, such as in a cap-and-trade system – for example, the EU Emissions Trading System (EU ETS) (see the blog ‘Carbon pricing in the UK‘). Then there is government investment in zero carbon technologies and infrastructure (e.g. electrifying railways). In practice, a range of policy instruments are needed (see the blog ‘Tackling climate change: “Everything, everywhere, all at once”‘).

With carbon capture, again, solutions can involve a mixture of market mechanisms and regulation. Market mechanisms include subsidies for using carbon capture systems or for afforestation. Regulation includes policies such as requiring filters to be installed on chimneys or banning the felling of forests for grazing land.

The main issue with such policies is persuading governments to adopt them. As we saw above, governments may be unwilling to bear the short-term costs to consumers and the resulting loss in popularity. Winning the next election or simple political survival may be their number-one priority.

COP28

The COP28 summit concluded with a draft agreement which called for the:

transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner, accelerating action in this critical decade, so as to achieve net zero by 2050 in keeping with the science.

This was the first COP summit that called on all nations to transition away from fossil fuels for energy generation. It was thus hailed as the biggest step forward on tackling climate change since the 2015 Paris agreement. However, there was no explicit commitment to phase out or even ‘phase down’ fossil fuels. Many scientists, climate interest groups and even governments had called for such a commitment. What is more, there was no agreement to transition away from fossil fuels for transport, agriculture or the production of plastics.

If the agreement is to be anything more than words, the commitment must now be translated into specific policy actions by governments. This is where the real test will come. It’s easy to make commitments; it’s much harder to put them into practice with policy measures that are bound to impose costs on various groups of people. What is more, there are powerful lobbies, such as the oil, coal and steel industries, which want to slow any transition away from fossil fuels – and many governments of oil producing countries which gain substantial revenues from oil production.

One test will come in two years’ time at the COP30 summit in the Amazonian city of Belém, Brazil. At that summit, countries must present new nationally determined commitments that are economy-wide, cover all greenhouse gases and are fully aligned with the 1.5°C temperature limit. This will require specific targets to be announced and the measures required to achieve them. Also, it is hoped that by then there will be an agreement to phase out fossil fuels and not just to ‘transition away’ from them.

Reasons for hope

Despite the unwillingness of many countries, especially the oil and coal producing countries, to phase out fossil fuels, there are reasons for hope that global warming may be halted and eventually even reversed. Damage will have been done and some tipping points may have been reached, but further tipping points may be averted.

The first reason is technological advance. Research, development and investment in zero carbon technologies is advancing rapidly. As we have seen, power generation from wind and solar is now cheaper than from fossil fuels. And this cost difference is likely to grow as technology advances further. This positive tipping point is becoming more rapid. Other technological advances in transport and industry will further the shift towards renewables and other advances will economise on the use of power.

The second is changing attitudes. With the environment being increasingly included in educational syllabuses around the world and with greater stress on the problems of climate change in the media, with frequent items in the news and with programmes such as the three series of Planet Earth, people are becoming more aware of the implications of climate change and how their actions contribute towards the problem. People are likely to put increasing pressure on businesses and governments to take action. Growing awareness of the environmental impact of their actions is also affecting people’s choices. The negative externalities are thus being reduced and may even become positive ones.

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Questions

  1. Use a diagram to demonstrate the effects of negative externalities in production on the level of output and how this differs from the optimum level.
  2. Use another diagram to demonstrate the effects of negative externalities in consumption on the level of consumption and how this differs from the optimum level.
  3. What was agreed at COP28?
  4. What incentives were included in the agreement to ensure countries stick to the agreement? Were they likely to be sufficient?
  5. What can governments do to encourage positive environmental tipping points?
  6. How may carbon taxes be used to tackle global warming? Are they an efficient policy instrument?
  7. What can be done to change people’s attitudes towards their own carbon emissions?

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

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Questions

  1. Why might countries not do ‘everything, everywhere, all at once’ to avert climate change?
  2. What might an optimist conclude from the ICC report?
  3. To what extent is climate change an economic problem?
  4. On a diagram similar to the one above, show how a subsidy could be used to internalise positive externalities.
  5. How might countries reduce the consumption of fossil fuels in the most efficient way? Are they likely to want to do this? Explain.
  6. Is a ‘cap-and-trade’ (tradable permits) system (a) an effective means of reducing emissions; (b) an efficient system?