Informing Global Population Projections. A Survey on Experts’ Opinions

Gailey Nick, IIASA
Anne Goujon, International Institute for Applied Systems Analysis (IIASA)
Ueffing Philipp, JRC
Fabrizio Natale, European Commission - Joint Research Centre

Insight into the future of the world population is key for policy planning. At present, several organisations engage in developing global long-term population projections and provide varied results in terms of projected population size and structures. This diversity demonstrates that there is a need to reflect on the ingredients that feed into the projections. The Global Demography Survey offers a way to address this need by asking experts to assess the validity and relevance of alternative arguments about the forces that could shape future fertility, mortality, and migration trends in the country of their choice. The results of the survey highlight that experts almost unanimously support the roles played by urbanisation, reductions in child mortality, greater educational attainment, and employment opportunities for women in decreasing fertility in high fertility countries. At the same time, life expectancy is expected to continue increasing across world regions, with the most significant improvements projected by experts in current 'low mortality' countries. Experts on migration mostly agree that climate change will lead to a rise in immigration. However, there is less agreement on the forces driving emigration. As a broad conclusion, the expert opinions seem to indicate that demographic challenges of the future do not necessarily have demographic solutions, and will instead necessitate improved adaptive capacities among all societies.

See extended abstract

 Presented in Session P3. Migration, Economics, Policies, History