Even with strong climate policies in place, population growth is a net burden on the climate, according to new research by Peter Kruse-Andersen, to be presented at the annual congress of the European Economic Association in August 2020. Thus, reducing the global population growth rate helps mitigate climate change.
The study also finds that compliance with the Paris Agreement can be ensured through a global carbon tax. The size of this tax depends negatively on the population growth rate. Research subsidies are generally insufficient to ensure compliance with the Paris Agreement, although a combination of research subsidies and a stagnation of the global population size may ensure compliance.
The global population is expected to increase by around 40% over the remaining part of this century. These more than three billion additional people will put severe pressure on the climate given current production technologies and lifestyle choices.
On the other hand, population growth increases the number of people who may contribute to the development of climate change solutions. In other words, a larger population implies a larger research capacity of the global economy, which may be used to mitigate climate change.
The new study analyses these two counteracting effects of population growth on climate change using a novel economic climate change model.
The study finds that the environmental burden of population growth can be reduced through climate policies. A tax on carbon emissions or research subsidies can direct research toward environmentally friendly technologies, thereby exploiting the additional research capacity caused by population growth to reduce carbon emissions.
Nevertheless, the study finds that even with strong climate policies in place, population growth is a net burden on the climate. Thus reducing the global population growth rate helps mitigating climate change.
Model simulations show that compliance with the temperature target of the Paris Agreement is achievable through a global tax on carbon emissions. The size of this tax depends critically on the assumed population growth scenario, where faster population growth implies a higher carbon tax.
In contrast, the model simulations show that a global subsidy to research in environmentally friendly production technologies cannot ensure compliance with the Paris Agreement under expected population growth scenarios. In fact, to ensure compliance with the agreement, the research subsidy must be combined with zero population growth through the remaining part of this century.
Name: Peter Kjær Kruse-Andersen
Position: Assistant Professor
Department: Department of Economics
University: University of Copenhagen
University website: https://www.economics.ku.dk/staff/vip/?pure=en/persons/373929
Personal website: https://sites.google.com/site/pkkruseandersenswebsite/home
Work phone: +45 35 33 47 92