Justin Gillis and Celia W. Dugger The New York Times 3 May 11;
The population of the world, long expected to stabilize just above nine billion in the middle of the century, will instead keep growing and may hit 10.1 billion by the year 2100, the United Nations projected in a report released Tuesday morning.
Growth in Africa remains so high that the population there could more than triple in this century, rising from today’s one billion to 3.6 billion, the report said — a sobering forecast for a continent already struggling to provide food and water for its people.
The new report comes just ahead of a demographic milestone, with the world population expected to pass 7 billion in late October, only a dozen years after it surpassed 6 billion. Demographers called the new projections a reminder that a problem that helped define global politics in the 20th century, the population explosion, is far from solved in the 21st.
“Every billion more people makes life more difficult for everybody — it’s as simple as that,” said John Bongaarts, a demographer at the Population Council, a research group in New York. “Is it the end of the world? No. Can we feed 10 billion people? Probably. But we obviously would be better off with a smaller population.”
The projections were made by the United Nations population division, which has a track record of fairly accurate forecasts going back to the 1950s. In the new report, the division also raised its forecast for the year 2050, estimating that the world would likely have 9.3 billion people then, an increase of 156 million over the previous estimate for that year, published in 2008.
Among the factors behind the upward revisions is that fertility is not declining as rapidly as expected in some of the world’s poorest countries, and has shown a slight uptick in some wealthier countries.
The director of the United Nations population division, Hania Zlotnik, said the world’s fastest-growing countries, and the wealthy Western nations that help to finance their development, face a choice about whether to renew their emphasis on programs that encourage family planning. Though they were a major focus of development policy in the 1970s and 1980s, such programs have stagnated in many parts of the world, partly because they got caught up in ideological battles over abortion, sex education and the role of women in society.
Over the past decade, foreign aid to pay for contraceptive commodities — $238 million in 2009 — has barely budged, according to United Nations estimates. The United States has long been the biggest donor for such programs, but the budget compromise in Congress last month reduced support for such efforts.
“The need has grown, but the availability of family planning services has not,” said Rachel Nugent, an economist at the Center for Global Development in Washington, a research group that monitors such issues.
Dr. Zlotnik said in an interview that the new numbers were based on an extensive revision of the methodology her division uses in its forecasts, incorporating new computer techniques and the latest demographic trends. She said that while her division was confident in the new approach, she cautioned that any forecast looking 90 years into the future comes with a slew of caveats.
That is particularly so for some fast-growing countries in Africa, Asia and the Middle East whose populations are projected to skyrocket over the next century. For instance, Yemen, a country whose population has quintupled since 1950 to 25 million, would see its numbers quadruple again, to 100 million, by century’s end, if the reports projections proved accurate. Yemen is heavily dependent on food imports and facing a critical shortage of water, and many experts do not believe its fast population growth can be sustained.
In Nigeria, the most populous country in Africa, the report projects that population will rise from today’s 162 million to a whopping 730 million by 2100. Malawi, a small country of 15 million people today, could grow to 129 million, the report projected.
The implicit, and possibly questionable, assumption behind these numbers is that food and water will be available for the tens of millions yet unborn, and that potential catastrophes ranging from climate change to wars to epidemics will not serve as a brake on population growth. Yet attempts to raise agricultural output in African countries have been highly uneven, ground water is being pumped at unsustainable rates in some countries of Asia, and this century, rising sea levels from global warming are expected to displace millions.
The projections “represent what would happen if today’s recipe continues to apply,” Dr. Zlotnik said. “But it is quite possible for several of these countries that are smallish and have fewer resources, these numbers are just not sustainable.”
Despite the lack of focus on population policy, ample proof has become available that well-designed programs can bring down growth rates even in the poorest countries, and can do so without the kind of restrictive policies put into place in China. Providing women with information and voluntary access to birth-control methods has contributed to their having fewer children in societies as diverse as Iran, Sri Lanka, Bangladesh, Mexico and Thailand.
One message from the new report is that the AIDS epidemic, devastating as it has been in many parts of the world, has not been the demographic disaster that was once predicted. Prevalence estimates and projections for the human immunodeficiency virus made for Africa in the 1990s turned out to be too high, and in many populations, treatment with new drug regimens has cut the death rate from the disease.
But the survival of millions of people with AIDS who would have died without treatment, and falling rates of infant and child mortality on the continent — both heartening trends — also mean that fertility rates for women need to fall faster to curb population growth, demographers said.
Numerous other factors have slowed change in Africa, experts said. They include women’s lack of power in their relationships with men, traditions such as early marriage and polygamy, and a dearth of political leadership. “In many African countries, the leaders there are not convinced that they have an issue with population,” Dr. Zlotnik said.
While about three-quarters of married American women use a modern contraceptive during their child-bearing years, the comparable proportions were only at a quarter of women in East Africa, one in 10 in West Africa, and a mere 7 percent in Central Africa, according to United Nations statistics.
“West and central Africa are the two big regions of the world where the fertility transition is happening, but at a snail’s pace,” said John F. May, a World Bank demographer.
And some studies suggest that providing easy, affordable access to contraceptives is not always sufficient to bring about a significant reduction in unwanted births. A randomized trial conducted by Harvard researchers in Lusaka, Zambia found that only when women had greater autonomy to decide whether to use contraceptives did they have significantly fewer children.
Other studies have found that general education for girls plays a critical role in that literate young women are simply more likely to understand that family size is a choice.
The report also highlighted a converse problem that is beginning to plague some developed countries: populations that are stagnant or even falling. Fertility has fallen below replacement level in many of the world’s rich countries and unless they open their borders to extensive immigration, some face a future with too few young workers to pay the carrying costs for retirees.
The new report suggests that China, once plagued by runaway population growth, could soon enter the ranks of countries with declining populations. The report projects that the Chinese population will peak at 1.4 billion in the next couple of decades, then begin falling, declining to 941 million by 2100. India would become the world’s largest country by mid-century, with a 2050 population projected at 1.7 billion, up from today’s 1.2 billion.
Whether the Chinese population actually peaks that early will likely depend, in part, on whether that country lifts its one-child-per-family policy. Many demographers expect the government to lift the policy entirely in the next few years.
The United States is growing faster than many of the world’s other rich countries, largely because of high immigration and a higher fertility rate among Hispanic immigrants. The new report projects that the United States population will continue to grow throughout this century, rising from today’s 313 million to reach 403 million by 2050 and 478 million by 2100.
Neil MacFarquhar contributed reporting.
