8 Country-level carbon budgets

Climate policy is mainly pursued through government action at the national level. Therefore, it is important for individual countries to know how much they are still allowed to emit under the Paris Agreement. Once we have selected the remaining global carbon budget, we can now convert this global budget into country-level budgets. However, this implies a distributional question that is not scientific but ethical and a question of climate justice.

As a starting point for solving this question, climate scientist Professor Stefan Rahmstorf proposes an equal per capita distribution as a universal and simple rule for distributing the remaining global carbon budget among humankind.10 At the same time, he states that there could be good reasons to argue against this way of allocation from different perspectives:

Anyone who wants more of the budget than someone else would need to provide a good reason. There could be many reasons – cold countries might claim they need more emissions for heating, hot countries for air conditioning, large countries for transport over long distances, developing countries to eradicate poverty, rich countries because they are already developed.

— Stefan Rahmstorf11

Now that we use the per capita rule as a simple method for distributing the carbon budget and that we have chosen a global budget as described in the previous steps, we need to take a few more steps to determine the country-level budgets.

Once we have decided on the global budget, we need to choose a point in time when this budget will be distributed. This step in itself raises profound questions of climate justice, which we will return to in a later section. For now, let’s take the year of the Paris Agreement, 2016, as the date for distributing the global carbon budget.12

So we take the remaining global carbon budget at the beginning of 2016 and distribute it according to each country’s share of the world population in the same year. Then we only need to subtract the additional emissions of the respective country in the following years to get the remaining carbon budget for a given country. The following app does exactly that.

Explore the data: With this app you can select the carbon budget for various countries.

Go to app

In the next section, you can use what you learned in the previous steps to build scenarios about the reach of the carbon budget under different assumptions for the future rate of economic growth and the speed of decoupling of CO2 emissions from economic activity.