Numbers count

The world is bracing for a population explosion but few have any solutions

The latest United Nations statistical projection shows the global population, currently 7.2 billion, barreling past 8.1 billion by 2025, to 9.6 billion people by the year 2050, and then almost 11 billion by 2100.

For context, the world's population passed 6 billion in 1999, and only reached 7 billion in 2011.

The new assessment is almost 800 million people higher than the previous global population estimate of 10.1 billion, which was calculated in 2011.

The projected growth will be led largely by booming fertility in Africa, where the current population of about 1.1 billion may quadruple to almost 4.2 billion by the end of the century.

"Although population growth has slowed for the world as a whole, this report reminds us that some developing countries, especially in Africa, are still growing rapidly," said the United Nations Under-Secretary-General for Economic and Social Affairs, Wu Hongbo, in a press release.

John Wilmoth of the UN's Department of Economic and Social Affairs acknowledged in a UN press conference that the new figures are only estimates, though projections based on current fertility and longevity rates are generally a reliable indicator of future population growth.

The report, called World Population Prospects: the 2012 Revision, uses computational methods developed by statistics and sociology professor Adrian Raftery and his colleagues at the University of Washington.

Previous UN calculations provided high and low future population projections based on the assumption that women will have about half a child more or less than the most specific projection. That method projects an enormous range by the year 2100, from 7 billion to 17 billion.

The University of Washington group's fine-tuned methods, however, led to much more specific intervals, from 9 billion to 13 billion by the end of the century.

The researchers' refined statistical techniques allowed them to anticipate life expectancy and fertility trends based on updated UN demographic data from 2010, leading to a surprising conclusion about Africa in particular.

"The fertility decline in Africa has slowed down or stalled to a larger extent than we previously predicted, and as a result the African population will go up," said Raftery in a university news release.

According to a helpful population graphic from the Guardian, India will surpass China as the world's most populous nation by 2028, when both countries average 1.45 billion people. After that point, India will keep growing to around 1.55 billion by 2100, while China's population will shrink to about 1.09 billion.

Meanwhile, Nigeria will leave the United States, currently the world's third most populous nation, in the dust by 2050. While the United States is expected to grow from 316 million today to around 462 million by 2100, Nigeria will boom from a mere 163 million two years ago to 914 million by the end of the century.

While the populations of currently developed nations are likely to remain stable at about 1.3 billion until 2050, or decline slightly, the 49 least developed countries are expected to double in size from about 900 million today to 1.8 billion in 2050.

Fertility rates are quickly dropping among current highly populous nations like China, India, Indonesia, Iran, Brazil, and South Africa. However, this is unlikely to provide a solution given the massive struggle for resources already taking place in these regions.

The situation is made worse by worsening economic problems even in developed countries. Populous developing countries such as Brazil saw the worst protests in over 20 years erupt on Tuesday as people clashed with government troops over corruption and a breakdown in public services. The relentless drive for development has also resulted in clashes in countries such as Turkey where protests erupted over government attempts to pave over a park to build a mall.

This relentless struggle has affected countries as far apart as Peru and Afghanistan where local communities are battling multinational companies to protect their environment from mines. A five billion U.S. dollar mine project in Peru will drain an ancient lake in the Andes while one of Afghanistan’s oldest artefacts will be lost to a copper mine.

Experts believe that the only way around this problem is to increase family planning, promote education of women and build a more equitable society. Yet these remain massive challenges for most countries around the world, paving the way for a contentious future for all.

Uditha Jayasinghe

APD staff writer