The magazine Science published a paper that contains alarming news from several demographers from several universities and the United Nations Population Division that conclude that the global population estimates previously expounded need to be changed. It was thought that in the second half of the 21st Century that populations would level off but new figures predict far more than the 7 billion people the previous estimates stated.
Using “probablilistic” statical methods the Science paper shows a range of uncertainty around its central estimate of 9.6 billion people in 2050 to 10.9 billion by 2100. The method they used instead points to an 80% chance of the actual number of humans on Earth in 2100 will be in the range of 9.6 billion to 12.3 billion. The range revealed in the paper, “is the truly innovative part,” according to John Wilmoth who is head of the UN Population Division and one of the authors of the paper published by Science. “It’s a much more plausible analysis of uncertainty, but we may still be off by two billion.” he added. The other demographers of the UN had not hit a bullseye but close to that amount. The Global Environmental Change published a paper and also found in a forthcoming book, Wolfgang Lutz and his colleagues at the International Institute for Applied Systems Analysis in Vienna, Austria used a different method. This method involved canvassing a huge group of experts to debate that the population is more than probable to pea at 9.4 billion in 2075 and perhaps fall just under 9 billion by 2100.
Of surprise is that both groups believe that India will become the world’s most populated country with estimates peaking in the year 2070 and simmering down to about 1.5 or 1.6 billion by the year 2100. The researchers are divided on their estimates of the coming population decline in china and the coming population explosion in Southern Africa. The UN says the population of Africa could quadruple to nearly four billion. Africa would be as dense in population as China is today.
How the world will feed and sustain these massive populations the articles did not say. The challenge of government will be to initiate food and health care for these billions of people as well as possibly change on a massive scale how humanity will interact. Housing and new technologies may come into play that can alleviate any distress from these population estimates but only time will tell.