Why is population an important topic?
The human race has an enormous impact on this planet! We control and modify the Earth more than any other species. How do we meet the needs of human beings and also preserve Earth's finite resources, biodiversity, and natural beauty? This is the fundamental question of our time, and the challenge is becoming more problematic as we add more people. Meanwhile, in every locality, it's important to know how fast population is growing, so that we can build sufficient sewers, roads, power plants, and schools.
Do we know exactly how many people there are in the world today?
No. There are so many people on this planet that counting them up, exactly, is impossible. However, experts believe there are more than 6.8 billion people in the world today. This is a fairly reliable estimate. World population in 2000 was 2 times greater than it was in 1960, 4 times greater than 1900, and 10 times greater than 1700. After growing very slowly for tens of thousands of years, world population has grown very rapidly in the last few centuries and continues to do so.
How fast is the world's population growing?
In terms of net gain (births minus deaths), we are adding over 200,000 people to this planet every day, or 140 EVERY MINUTE. That equates to 70 million more people every year, about the same as the combined population of California, Texas, and New York. Although we have made encouraging progress in slowing the growth rate, any rate of growth is unsustainable in the long term, so we must stabilize population soon for the good of future generations.
Are there any parts of the world where population is not growing?
Yes. Roughly speaking, populations are holding stable (zero population growth) in Australia, Japan, and Western Europe. Populations are decreasing somewhat in Russia and some Eastern European countries. Growth in several southern African countries has slowed due to higher death rates because of AIDS. But population is growing either rapidly or very rapidly in every other part of the world right now, including India, Pakistan, Nigeria, the Democratic Republic of Congo, Bangladesh, Uganda, the United States of America, Ethiopia and China. In other words, population has stabilized where about 1.2 billion people live and is still increasing very rapidly where 4 billion people live -- those who can least afford it. Result: the annual net gain of over 70 million people!
I've heard some say the world population crisis is over and that it's not a problem anymore. Is this true?
No, absolutely not. First of all, 6.8 billion people may well be too many already. Cornell University professor David Pimentel's research shows that about 2 billion people is the number the planet can sustainably support, if everyone consumes the same amount of resources as the average European (which is less than the average American). Secondly, U.N. experts predict that world population will increase for at least the next 50 years, with a "most likely" prediction of 9 billion people by the year 2050. There probably will be additional growth beyond that.
There's no doubt that the worldwide average number of children per woman has come down over the last 50 years -- from more than 5 to less than 3 -- but: (1) the current average is still well above replacement level, which would be 2.1 children per woman, and (2) the number of women having children is about TWICE what it was in 1960. There is also huge "demographic momentum," since half the world's population is age 24 or younger -- either having children now, or poised to have them in the next 10 to 15 years -- so that any changes we make today may not have a visible effect until a generation has passed!
Finally, people are living longer all over the world and will continue to do so, with a resultant slowdown in death rates. Thus, there's a big imbalance in the birth to death ratio: currently about 5 births for every 2 deaths worldwide.
So much of the world is still empty space -- can't people just move to less crowded places?
A lot of that space isn't empty: vast tracts of farmland are necessary to feed the people who live in cities and towns, and forests are necessary to produce wood and oxygen. Much of the land that hasn't been settled by people simply isn't habitable: it's too dry, too cold, or too rocky. Besides, the people who are most overcrowded are struggling to exist on less than a dollar a day... they don't have the money to move!
The United States and other countries with low birth rates let in millions of immigrants each year. Doesn't this act as a "safety valve" to relieve the population pressure of the faster-growing countries?
Not really. Think of it this way. Each year the U.S. currently allows about a million people to immigrate legally (And another 500,000 to a million come in illegally.) But each year most countries of the developing world add almost 70 million more people to their numbers, net gain! The one to two million coming into the U.S. hardly make a dent to relieve the crushing problems created by the almost 70 million more people into these resource stressed countries -- each year!
If we continue letting in as many immigrants for the next 50 years as we have for the past 25, we will absorb only about 4 percent of the population growth from the less-developed countries! Although migration can greatly improve the lives of the immigrants themselves, it is not an effective way to relieve the population growth of the countries they come from.
I've heard that as population growth slows, countries like the U.S. are going to have to support increasing numbers of dependent elderly people. Don't we need to have more kids and increase immigration so that we'll have enough workers to support all these retired people?
No. First of all, people are dependent in their retirement years for only a fraction of the time they're dependent in their childhood. Right now retirement lasts only half as long as the dependent period before a young person enters the workforce. If trends continue, it may decrease to a third or even a quarter of that youthful dependency. So children are far more expensive to the economy than the elderly! Secondly, population growth has to stop sooner or later, so bringing in more people is not a long-term solution. The long-term solution is to restructure our system so that we don't need a constant influx of more people. The sooner we stop the increase in numbers, the more intact we leave our resource base for our children of the future.
What do you mean by "humane" population stabilization?
Population continues increasing because the death rate worldwide dropped much farther than the birth rate. Of course no one wants to see death rates rise. That would be an unthinkably inhumane way to stop population growth!
The humane way is for birth rates to drop and balance with today's lower death rates. Repeated studies in countries all around the world show that the longer children stay in school, the fewer children they will have. Smaller families can provide more resources for each child, and entire nations benefit when they have fewer children to drain their limited, declining resources. So education is the key to humane population stabilization.
Another highly successful educational approach involves the use of specially-created soap operas, both on TV and radio, that communicate -- even to illiterate people -- the benefits of having fewer children. These special soaps are currently running on every continent (except Antarctica) and are having an incredible impact to help reduce people's expectations about their "desired family size."
Our mission at World Population Balance is education because education is the key!
Many of the statistics on this page come from the Executive Summary of World Population Prospects, 2004 Revision.
I've heard people say that we could support far more humans on this planet than we've got right now, given improvements in modern technology. Is this true?
There's a lot more to it than just discussing how many people we could cram onto the planet. What about the quality of human life? What is the role of the human race? Should we keep trying to grow and artificially modify this planet more and more? Should we keep using up many precious resources faster than they can be replenished, leaving little or nothing for our great-grandchildren? Should we keep trying to test the limitations of natural resources, hoping that technology will continue to get ever more efficient? From a biological, ethical, and philosophical standpoint, it is far better for us to stabilize our own growth and preserve wilderness and wildlife. Wouldn't future generations want us to do that?
Are the world's resources really all that finite? For instance, I've heard we've got more than enough food for everyone on this planet.
Human food production capabilities are impressive, with U.N. data indicating almost one ton produced per capita per year, worldwide. However, much of this food never goes directly into the mouths of humans. Much grain, for instance, gets fed to livestock or is used for industrial applications or non-nutritious products like soft drinks. Also, there is a lot of rotting and spoilage, worldwide. More disturbing is the estimate that perhaps half the world's people are malnourished to one degree or another. (Humans need at least 40 different nutrients for good health). Production is not the only challenge. Distribution, warfare, poverty, transportation problems, and corruption play major roles, as well. All these problems have often been exacerbated -- if not caused -- by rapid population growth. These enormous challenges will become even more pronounced as we add more people!
Meanwhile, the environmental impacts of producing food are staggering: huge amounts of soil erosion and salinization (one third of the world's food is produced on irrigated land); deforestation; and resources used for fuel, fertilizer, pesticide, seed, etc. There are pollution and biodiversity problems caused by farm chemicals, as well. About a third of the world's land area is currently devoted to agriculture, but three quarters of that farmland is considered "poor" soil, and much is constantly declining to lower and lower quality. If we add more people, we'll ultimately need more farmland, and there's no more farmland available.
What about water resources? If freshwater supplies become tight, won't we just desalinate salt water from the ocean?
Fresh water, or lack thereof, could be the biggest single resource problem that the human race faces over this century. (The total supply of water in the Earth's biosphere remains constant, but most of it exists as saltwater in the oceans.) The U.N.'s report on global ecosystems (known as PAGE) rates the ecological health of world freshwater resources as "grim," with China, India, the Middle East, and Africa facing particularly severe crises. The southern U.S. will also face increasing shortages. Human activities currently use about half of the world's freshwater flow.
Desalinization technology exists and is currently being used in some Middle East countries. Tampa Bay is the first American city to desalinate water. It is expensive, and it uses up many other precious resources (including oil from finite supplies) in the process. And it poses additional transportation costs for areas that are far away from a coastline. The much bigger problem may be damage to biodiversity and ecosystems in coastal estuaries. More humans means ever-greater water demands, not just for household use but for agriculture, industry, and recreation.
Give me a quick rundown on the world energy situation. So what if we run out of petroleum? Won't we just find other energy sources?
Probably. After all, petroleum and cars represented a "solution" to the huge problem of horse manure in big cities a hundred years ago. But one thing's for sure: no energy source will be problem-free when it's used on a scale massive enough to meet the needs of billions and billions of humans. Meanwhile, people want new energy sources to be convenient, economical, safe, and practical. Even when technology accomplishes that, it still takes years for consumers to break away from existing "habits"- just as it's taking years to wean us away from fossil fuels and toward wind, solar, and fuel cells. Meanwhile, people in the developing world burn huge amounts of biomass, mostly wood and crop stalks. More people will mean more demand for energy, regardless of where they are located, and will increase the dilemmas we face. We'll have to artificially modify our ecosystems more and more. The sooner we stabilize our population, the better for our energy options and environmental impact.
Won't sending humans into space solve the population problem on Earth?
The resources it takes to send just eight or nine people into space right now are enormous! It takes massive teams of people and resources to accomplish this feat every several months. But we continue to add over 200,000 people a day to the world's population, net gain! It is highly doubtful that any time soon we will "solve" the world's population growth problem by sending over a million people into space every week!
At present, Earth is our "spaceship" -- and a very beautiful and fertile one at that, but it is one that is under tremendous ecological strain. There seem to be no other planets in our vicinity of space that could provide air, water, soil, and biodiversity in a manner readily useable by humans.