La population mondiale en 2050. Les projections démographiques des Nations unies à long terme

Every two years the Population Division of the UN updates its demographic data and revises its population projections accordingly. The last revision, in 2002, offered several scenarios for developments between now and 2050, based on different hypotheses about fertility and mortality rates and migration (for the analyses by country and region): a “high”, a “low” and a “medium” scenario, and one with fertility held constant. Julien Damon has examined these revised projections for Futuribles. He sets out the methodological problems associated with this type of exercise, and discusses the main trends in population change for the world as a whole as well as the breakdown by major groups (industrialized countries, developing countries, less advanced nations, etc.) and sometimes also projections for individual countries. He has chosen to focus on the medium scenario in order to make the projections more readily comprehensible; nevertheless, it is important to remember that this scenario is not necessarily the most likely, and the reason for providing a variety of projections is to offer a very wide range of possible outcomes (which can be criticized with regard to the underlying hypotheses), and nobody is able to say for certain which one is the most probable. According to the medium scenario, the world’s population will grow from 6.3 billion today to 8.9 billion in 2050. The developing countries are the main contributors to this increase, despite the negative impact of AIDS on population growth in a number of them. The gap between the standard of living in the developed countries compared with that in the poorer countries is therefore likely to widen. The phenomenon of ageing populations in the industrialized countries, especially in Europe, appears to be unavoidable. All of these trends potentially have serious social consequences.