How many will we be? Are population estimates off the mark?

Feb 20, 2011
“Almost all of the growth in world population will occur in poor countries, particularly in Africa and South Asia,” says the Population Council’s John Bongaarts. “But larger investments in family planning right now would have a very beneficial impact on human welfare and any environmental issue we care about.” Credit: The Population Council Inc.

In 2011 the Earth's population will reach 7 billion. The United Nations (UN) reports that the total number of people will climb to 9 billion in 2050, peak at 9.5 billion, stabilize temporarily, and then decline. Despite the confidence with which these projections are presented, in an American Association for the Advancement of Science press briefing and presentation today the Population Council's John Bongaarts presents evidence that the actual population trajectory is highly uncertain.

What could happen depends on trends in fertility and —and both variables are complex and not easy to forecast.

With respect to fertility, some analysts assume that the very low levels of childbearing now prevailing in Southern and Eastern Europe, where women have fewer than two children on average, will continue in those countries and spread to other parts of the world. But scholars have different expectations of how rapidly and widely that trend will unfold. If fertility remains higher than the UN projects the world could exceed 10 billion in 2100.

In terms of mortality, pessimists say that life spans in developed countries are close to the biological limit. However, optimists predict that life expectancy will continue to rise very rapidly, exceeding 100 years before the end of this century. If the optimists are right, the world's population could also exceed 10 billion in 2100. This higher population scenario also has implications for the solvency of social security systems that provide income to the elderly.

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Population Council Vice President John Bongaarts discusses overpopulation. Credit: This interview was originally published on the New Security Beat, the blog of the Woodrow Wilson Center's Environmental Change and Security Program.

"Almost all of the growth in world population will occur in poor countries, particularly in Africa and South Asia," says Bongaarts. "But if we make much larger investments in family planning right now, the number of people could be closer to 8 billion. Such an investment would have a very beneficial impact on human welfare and any environmental issue we care about."

Population Council vice president and Distinguished Scholar John Bongaarts conducts research on a variety of population issues, including the determinants of fertility, population-environment relationships, the demographic impact of the AIDS epidemic, population aging, and population policy options in the developing world. He is a member of the U.S. National Academy of Sciences and served as chairman of the Academy's Panel on Population Projections.

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fuviss_co_uk
1 / 5 (3) Feb 20, 2011
"However, optimists predict that life expectancy will continue to rise very rapidly, exceeding 100 years before the end of this century."

This is optimistic ??

I am sure that they did not here about Ray Kurzweil and Aubey de Gray. In my opinion it is very likely that biological death will be the thing of the past in 2050,maybe even between 2030-2050, if the progress in science and technology will continue
Quantum_Conundrum
1 / 5 (3) Feb 20, 2011
This article doesn't discuss the fact that hydroponics and nano-technology will make food production and manufacturing several times more efficient over the next few decades.

However, I will say that it is alarming when we think about the consequences of the fact that Africa, which is so plagued by ignorance, genocide, and superstition, will be a continent with 3 billion people inhabiting it by 2100, while the U.S. and Europe continue to shrink in population.

Where are these people going to get handouts when the western world can no longer afford to just rescue them every time something goes wrong?

And yes, "realistically" nano-technology to prevent heart attacks and disease, etc, and the ability to re-grow organs will probably eventually increase average human life expectancy by at least a few decades, even by the time you consider some people will still die from "sudden" heart failures, etc, but with regular checkups and nano-tech, many will be extended several decades.
cubefox
3 / 5 (2) Feb 20, 2011
@fuviss_co_uk
I am sure that they did not here about Ray Kurzweil and Aubey de Gray. In my opinion it is very likely that biological death will be the thing of the past in 2050,maybe even between 2030-2050, if the progress in science and technology will continue


Sure progress will continue, but not as fast as you think. In the past, sci-fi authors and professional futurologists have overestimated most of the the technological progress in the future. Some developments have been underestimated, like size, price and processing speed of computers. But those are more or less exceptions. It has been proven that humans are natural optimists -- they tend to overrate their future.

cubefox
1 / 5 (1) Feb 20, 2011
@QC
[b]This article doesn't discuss the fact that hydroponics and nano-technology will make food production and manufacturing several times more efficient over the next few decades.[/b]

This ist not a "fact".

[b]inhabiting it by 2100, while the U.S. and Europe continue to shrink in population.[/b]
correction: The us population does not shrink, it grows.
Quantum_Conundrum
1 / 5 (1) Feb 20, 2011
@QC
correction: The us population does not shrink, it grows.


No, it doesn't. Without foreign adoption and immigration, half of it illegal, the U.S. would have had a negative over the past decade or so, and the trend continues.

The tendency of people to have one or two children is also going to produce a genetic bottleneck, as it takes around 2.1 per couple, even in modern times, for population to be self-sustaining.
astro_optics
1 / 5 (1) Feb 20, 2011
The only way to stop the population explosion is to take away the incentive. Stop the emigration to the west, stop the handouts, and help/teach the third world to be self sustaining!