Predicting future population numbers remains a difficult issue. While popular (and populist) media tends to dramatise every new release of population predictions, it is less often discussed that these figures are one possible scenario for what is an extremely complex issue. Small political and cultural changes in societies can lead to drastic long terms effects that change the future numbers of people within a country. The current estimates are therefore never figures that are engraved in stone, but estimates that look at the current trends that we can observe. The different scenarios therefore have an extreme variability, ranging from a decline down to just above 6 billion to an increase up to almost 16 billion. These are of course the very extreme scenarios in the latest revision of the Unites Nations’ World Population Prospects that has just been released. While it is almost certain that any scenario is likely to not happen in that way, the trends outlined in the report are in important political guideline that tells, what humanity should be prepared for and which economic, ecological and other implications the different scenarios have for the future. The following map shows a population cartogram of the most recent population estimates where each country is resized to its total population in 2013 (approximately 7.1 billion):
The world’s population has reached the symbolic milestone of adding another billion to this planet. While 7 billion is a static number, the expansion and distribution of the world’s population is a very dynamic issue that a single map of where these 7 billion are living (as shown on this website back in July) does not do full justice of what is happening on the planet of people. A lot has changed from the 2.5 billion people that lived on the planet in the middle of the last century to today’s 7 billion, moving the gravitational centre of people considerably towards Asia. This has now started turning towards the African continent, which has not only been a considerable part of the global population growth over the last quarter of the century (and is therefore home to a large share of the world’s children), but is expected outnumber Asian population growth considerably in the decades to come.
The following cartogram-map animation shows these changing trends between 1950 and 2100. It is based on United Nations probabilistic population projections of total fertility from the 2010 Revision of the World Population Prospects. From the year 2010, the data is based on a future projection of expected population changed. “To project the population until 2100, the United Nations Population Division uses assumptions regarding future trends in fertility, mortality and international migration. Because future trends cannot be known with certainty, a number of projection variants are produced” (quoted from the WPP documentation). I used the data from the probabilistic median variant, in which the population is expected to grow to approximately 10 billion by the year 2100 (see below for a graph of the different scenarios produced by the UN). The animation therefore shows the changing distributions of population between the different countries (note that South Sudan is not included in the estimates; Sudan is therefore treated as one country in this map), with Europe losing large shares of population in total as well as in relation to the rest of the world, while the dominance of Asia slowly starts to be relativised by the increasing population shares on the African continent, making the changes in the Americas almost insignificant from a global perspective: