Are we still on track for 9 billion people on Earth in 2050?

Some population experts are now wondering if an often-cited number – 9 billion people by the year 2050 – is big enough.

I was born in 1951. So I remember walking into public places and not having to stand in line.

We were so innocent then. Things changed quickly in my town, which soon became a city, with one person ahead of you in line suddenly becoming 5 people, or 50 people. Changing attitudes about customer services contributed, too, as did many the tech companies that moved to the U.S. sun belt, bringing their employees. Now – in the same town where I’ve lived all these decades – we all wait more or less patiently in line everywhere, in banks, stores, movie theaters, airports, to straighten out your cell phone bill or just to buy a hot dog at the park. For me, the phenomenon of standing in lines is a personal marker of population growth – a powerful remembered contrast from the 1950s and 60s.

In the 1960s, Earth had only 3 billion inhabitants. Now global population numbers are on track to reach 7 billion in 2011, just 12 years after reaching 6 billion in 1999, according to the Population Reference Bureau of Washington D.C.

Have you experienced a shift in population where you live? Do you have personal memories of a less populated world?

If you do, maybe you wonder what ordinary things around us will change in ways we don’t expect, as more and more people come to inhabit the Earth. True, U.S. population isn’t expected to grow as much as other places on the planet. The most growth is expected in Africa and Asia, where three-quarters of the world’s current population already live.

Our human population is growing larger. And, according to a recent article by Robert Engelman of the Worldwatch Institute, the population growth rate has held steady in recent years. That sounds like a good thing, but it may not be. This steady growth has surprised demographers, who’d been expecting the rate of growth to decrease. According to Engelman, some population experts are now wondering if an often-cited number – 9 billion people by the year 2050 – is big enough.

Prior to this – during the 1990s – the rate of population growth was decreasing. We have these ‘rate of’ conversations in our office frequently, because they can be confusing. It’s not that there are fewer people being born – not at all. We’re talking about a growth rate, that is, the rate at which new humans are being added to the planet’s total population each year. That rate was decreasing. Now it’s not. Engleman says that, in the 1990s, the number of new humans added to global population each year fell from nearly 90 million people to less than 80 million. Since 1999, however, the number has fallen to only about 79 million people added to Earth’s total population each year. So you can see that rate of population growth has been more or less constant in this century, contrary to the expectations of demographers.

The most often quoted population number of 9 billion by 2050 comes from the United Nations Population Division. As Engleman points out in his article, the U.N. doesn’t predict. Instead, it projects, or makes conditional assessments based on current population numbers, age structure of humans around the world, and trends and reasonable assumptions about the future. These U.N. projections suggest a range for global population in 2050, from slightly less than 8 billion to slightly more than 11 billion. Now it sounds to me as if Engelman is suggesting that we may be headed for the higher end of that range, rather than the lower end.

Engelman believes there are two population-related trends that may be related to the current growth rates . First, he says, global assistance for family planning services – contraceptives plus information on how to use them safely and effectively – in poor countries is falling significantly. Second, ironically, there have been major boosts in recent years among the largest health donors in spending to address the HIV/AIDS pandemic. I’ll leave it to you to contemplate the connection of these two trends with the leveling off of population growth rates, or you can read more in Engelman’s article.

Meanwhile, the Danish Aging Research Center at the University of Southern Denmark just announced a study suggesting that most babies born today will live 100 years. I don’t know enough about the U.N. studies to know how often they re-calculate their projections or how recent their longevity data are, but the wildcard of humans living longer also seems important, to say the least.

Today, according to the U.S. Census Bureau population clocks we human souls number 6,788,426,733. I checked this number several times while writing this post, and it’s shocking to see how fast it changes. Go ahead. Check it for yourself now. That’s because, according to WikiAnswers, there are 255 babies born every minute in the world.

WikiAnswers used population data from 2007 to calculate their babies/minute rate. Due to the leveling out of population growth in the past several years … it’s likely that rate still stands.

If I live to be 100, I’ll make it to the year 2050. I have to admit, I’m very very curious about what the world will be like then, and committed to learning as much as I can about the intricacies of our burgeoning human population on this little Earth.

Most Babies Born Today Will Live 100 Years, Scientists Say

2009 World Population Data Sheet

Deborah Byrd