Laying down the rules to address climate change: the outcome of COP24

In 2015, at the COP21 climate change conference in Paris, an agreement was reached between the 195 countries present. The Paris agreement committed countries to limiting global warming to ‘well below’ 2°C and preferably to no more than 1.5°C. above pre-industrial levels. To do this, a ‘cap-and-trade’ system would be adopted, with countries agreeing to limits to their emissions and then being able to buy emissions credits to exceed these limits from countries which had managed to emit below their limits. However, to implement the agreement, countries would need to adopt a ‘rulebook’ about how the permitted limits would be applied, how governments would measure and report emissions cuts, how the figures would be verified and just how a cap-and-trade system would work.

At the COP24 meeting from 2 to 15 December 2018 in Katowice, Poland, nearly 14 000 delegates from 196 countries discussed the details of a rulebook. Despite some 2800 points of contention and some difficult and heated negotiations, agreement was finally reached. Rules for targeting, measuring and verifying emissions have been accepted. If countries exceed their limits, they must explain why and also how they will meet them in future. Rich countries agreed to provide help to poor countries in curbing their emissions and adapting to rising sea levels, droughts, floods and other climate-induced problems.

But no details have been agreed on the system of carbon trading, thanks to objections from the Brazilian delegates, who felt that insufficient account would be made of their country’s existing promises on not chopping down parts of the Amazon rainforest.

Most seriously, the measures already agreed which would be covered by the rulebook will be insufficient to meet the 2°C, let alone the 1.5°C, target. The majority of the measures are voluntary ‘nationally determined contributions’, which countries are required to submit under the Paris agreement. These, so far, would probably be sufficient to limit global warming to only around 3°C, at which level there would be massive environmental, economic and social consequences.

There was, however, a belief among delegates that further strong international action was required. Indeed, under the Paris agreement, emissions limits to keep global warming to the ‘well below 2°C’ level must be agreed by 2020.

Climate change is a case of severe market failure. A large proportion of the external costs of pollution are borne outside the countries where the emitters are based. This creates a disincentive for countries acting alone to internalise all these externalities through the tax system or charges, or to regulate them toughly. Only by countries taking an international perspective and by acting collectively can the externalities be seen as a fully internal problem.

Even though most governments recognise the nature and scale of the problem, one of the biggest problems they face is in persuading people that it is in their interests to cut carbon emissions – something that may become increasingly difficult with the rise in populism and the realisation that higher fuel and other prices will make people poorer in the short term.



  1. To what extent can the atmosphere been seen as a ‘global commons’?
  2. What incentives might be given for business to make ‘green investments’?
  3. To what extent might changes in technology help businesses and consumers to ‘go green’?
  4. Why might international negotiations over tackling climate change result in a prisoner’s dilemma problem? What steps could be taken to tackle the problem?
  5. How would an emissions cap-and-trade system work?
  6. Investigate the Brazilian objections to the proposals for emissions credits. Were the delegates justified in their objections?
  7. What types of initiative could businesses take to tackle ‘supply chain emissions’?
  8. How could countries, such as the USA, be persuaded to reduce their reliance on coal – an industry lauded by President Trump?