Growth Slows as Population Hits 6 Billion
Despite common perceptions that the pace of the world’s population growth is spiraling out of control, women around the globe are having fewer children than their mothers and the birthrate is now declining in every nation on the planet.
This phenomenon--which has taken shape worldwide in the last year or so--is driving projections by scientists that worldwide population is moving toward stabilization or even a slight decline, perhaps as early as 2050.
Today is the “Day of 6 Billion”--designated by the United Nations as the likely day when a newborn child will raise the Earth’s population to 6 billion. No one actually knows when, or where, that 6-billionth person will be born. But population experts agree that the 6-billion mark was or will be reached within a few months before or after Oct. 12, 1999.
While the number of people inhabiting the Earth continues to grow and put inordinate stresses on its natural resources, demographers agree that the pace is slowing substantially.
The United Nations now projects that as more people move to urban areas and choose to have fewer children, population will peak at about 10 billion.
“Many people would be surprised to learn that the growth rate is declining. People think it’s out of control, that population is growing like cancer,” said Thomas Buettner, a demographer who is the U.N.’s population affairs officer.
“But if you look hard, you see many signs that not only suggest the possibility--but are backed by some very solid science--that stabilization will occur . . . or go into the negative.”
Under one of three scenarios developed by U.N. demographers, the number of people on the planet could begin dropping in 50 years. The more likely scenario, they say, is in about 200 years.
But population increase is far from over.
In a handful of African nations, each woman on average raises seven children--fewer than their mothers but still enough to drive up global averages. Another 78 million people inhabit the world every year--almost entirely in poor, developing nations--adding the equivalent of a new city the size of San Francisco every three days. As the population rises, ever-increasing portions of the Earth’s resources are consumed and the quality of life is altered.
One-sixth of the human population lacks what U.N. Population Fund Executive Director Nafis Sadik calls the “elements of human dignity--clean water, enough food, secure housing, basic education and health care.”
Impact on Environment
Population lies at the root of many of the world’s most pressing environmental problems, said Carl Pope, executive director of the Sierra Club. Urban air pollution, depleted drinking water, global warming, rain forest destruction and species extinction are among the problems that can be linked in part, he says, to too many people sharing resources in an unsustainable way.
“As population grows, all these people will eat food, drink water and consume wood products and fossil fuels,” Pope said. “So a decline in the population rate is very, very important because we are undergoing a major league collapse of our renewable resources.
“How many people can the resources of the planet, and the needs of other species, sustain in reasonable prosperity? I suspect 6 billion is probably already too many, and 6 billion is a lot less than 10 billion,” he said.
The latest billion was reached more rapidly than at any time in history--it took only a dozen years. Yet the population is now growing by only 1.3% per year--considerably slower than the 2% peak in the late 1960s--and the U.N. projects it will most likely slow to 0.3% in 2050.
War, recession, famine, political overthrows and epidemics can all alter birth and death rates. Demographers don’t even try to forecast these unforeseeable events. Instead, they look country by country and develop projections of how fertility is likely to change given the social and cultural structure.
The United Nations, which has gauged population in this manner since 1947, seems to be on target. Back around 1970, it was predicted the 6-billion mark would be reached right around now, Buettner said.
“No one can really forecast the future of population. What’s more important is what has happened in the last few years, and indeed, population growth rates and fertility rates have all come down faster than anyone projected,” said Robert Engleman, vice president for research at Population Action International, a U.S.-based group working on slowing population growth.
Some researchers, like those at Worldwatch Institute, a Washington, D.C., think tank, believe that as death rates rise and birthrates drop in poor nations, population will start declining even more rapidly than the U.N. projects.
The number of babies per woman has dropped so consistently that the U.N. a year ago revised its estimate: The world will grow by 78 million people a year rather than the 86 million recorded between 1985 through 1990.
Rising death rates are responsible for a modest part of the slowdown. The AIDS epidemic, especially in Africa, has caused life expectancy to drop much more than anyone predicted. Brian Halweil, a staff researcher at Worldwatch, said depletion of water supplies in the Nile River basin is so severe that the region’s explosive growth is likely to end as deaths rise.
But experts say decisions by individuals to have smaller families, and to delay their pregnancies, are the primary factors putting the brakes on the population surge.
From 1950 through 1955, women on average had nearly twice as many children as they do today--five, compared with today’s 2.71. In Mexico, the average family size has dropped since 1965 from seven children to 2.5.
“We have virtually no country anymore that has not started at least a modest fertility decline,” Buettner said.
The U.N.’s Sadik tells of meeting a woman in China who has only one child even though she lives in an area where the nation’s one-child rule does not apply. Her in-laws are pressing her to have more children, but she told Sadik she wanted to wait until after her family could afford another sheep.
Her decision is not much different from that of a woman in Manhattan who wants to wait until she can afford a larger apartment, said Corrie Shanahan, a spokeswoman for the United Nations Population Fund.
Urbanization and wider access to birth control are the main reasons women can make the choice to have fewer children. As people move from rural farm areas to urban ones, they need fewer hands to help with manual labor. Also, more women have paying jobs and greater access to education, contraception and family planning--all factors that usually lead to fewer children and a later start in pregnancies.
Populations Shift as Birthrates Change
Even in some rural countries, such as Bangladesh, parents are choosing to have fewer children because land is scarce and their offspring have to split the acreage handed down.
Demographers say that if women on average have fewer than 2.1 children each, generations are not replacing themselves. But the current global birthrate remains 30% higher, at 2.71 children per woman.
Nearly all developed countries--including the United States, all of Europe and most of eastern Asia--have birthrates below the level that sustains their current population size.
But developing countries bring up the average. In Yemen, for example, each woman averages 7.6 children, the highest rate in the world. Even there, however, the rate is declining.
The rapid birthrate decline in developed nations has caused major shifts in population. Africa, in the last two years, became larger than Europe. Two out of every five people live in India or China.
How quickly the population stabilizes will be largely up to the world’s 1 billion teenagers. Environmental activists and the U.N. Population Fund say they need wider availability of family planning and contraception.
Birth control, though, remains controversial for some cultures and religions. For example, the Catholic Church, although it now supports some family planning education efforts, remains opposed to contraception and abortion.
As birthrates drop, some fear that people and their governments could become complacent, believing that population growth is taking care of itself.
“What really isn’t clear is whether governments will continue to make the progress they have made in providing reproductive care. If they don’t, fertility decline could be stalled,” Engleman said.
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World Population Profile
Fertility rates--the number of children per woman--are declining in every nation around the world, even though women in some countries are still averaging seven children apiece. For birth rates to stabilize, women on average must have fewer than 2.1 children.
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Current global rate: 2.71
United States: 1.99
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* Ten highest fertility rates
Yemen: 7.60
Somalia: 7.25
Uganda: 7.10
Afghanistan: 6.90
Nigeria: 6.84
Angola: 6.80
Malawi: 6.75
Mali: 6.60
Burkina Faso: 6.57
Ethiopia: 6.30 *
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* Ten lowest fertility rates
Spain: 1.15
Romania: 1.17
Czech Republic: 1.19
Italy: 1.20
Bulgaria: 1.23
Latvia: 1.25
Slovenia: 1.26
Greece: 1.28
Estonia: 1.29
Germany: 1.30
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* U.N. Population Predictions for 2050
The U.N. predicts that the world’s population is most likely to grow from today’s 6 billion to 8.9 billion by 2050. The current annual rate of population growth is 1.3%, but under all scenarios developed by U.N. demographers, that rate would slow considerably by 2050.
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High scenario
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10.7 billion people
0.86% annual growth
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Medium scenario
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8.9 billion people
0.34% annual growth
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Low scenario
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7.3 billion people
0.23% annual loss
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Source: United Nations Population Division, State of World Population Report, 1999
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