How much further will the global population expand? Can all these extra mouths be fed? And what is the role in this story of economic growth? These fundamental questions are scrutinized in a study by Dr. Bruno Lanz (CIES), Prof. Simon Dietz (LSE), and Prof. Tim Swanson (CIES), which is forthcoming in the International Economic Review, and available here. The authors take a novel perspective on the topic by formulating a model of economic growth in which global population, food production, agricultural land, technological progress, and per capita income are jointly determined. They demonstrate that the model is able to closely replicate global development paths observed from 1960 to 2010, and then use the model to evaluate possible global trajectories up to 2100. 

The core results suggest that global population can be expected to grow further over the course of the 21st century, reaching 12.4 billion in 2100, together with a doubling of GDP per capita and agricultural production. However, agricultural land area is expected to stabilize by 2050 around 10 percent higher than what is currently observed. While growth in these outcomes all decline over time, these results represent a "business-as-usual'' view of the world. The role negative feedback mechanisms such as climate change, the erosion of agricultural productivity, or global biodiversity losses, are studied in companion papers available here and here.