Memo to Earth: Expect 11 Billion People by 2100

July 11th was World Population Day, an annual event begun by the United Nations to build awareness about population growth and its impacts. The news in this 25^th year of the event is discouraging.

The UN last month announced upwards revisions of earlier growth projections made just two years ago. In only a dozen years, world population – now at 7.1 billion – is estimated to reach 8.1 billion. The prior projection was 8 billion. For perspective, adding another 100 million people to the planet is equivalent to adding the current population of the Philippines.

In other words, it’s a whole lot of people.

By 2050, the estimate is 9.6 billion people – up from 9.3 billion – and by 2100, the world population is expected to reach 11 billion – up from the prior projection of 10.1 billion.

The difference between 11 billion and 10.1 billion – 900 million – is almost equivalent to adding the combined populations of today’s third through sixth most populated countries (the United States, Indonesia, Brazil and Pakistan).

So projections point to another 3.9 billion people in less than a century. It took all of human history to reach a world population of 4 billion in 1975, and we’re headed towards adding that amount of people in just a few decades.

Scary. Staggering. Almost incomprehensible.

Some have pointed out that this extreme growth will be in regions that are least prepared to handle it. This includes sub-Saharan countries, Indonesia, Pakistan and the Philippines. I’ll argue that we all are in this together, and we will all feel this growth acutely and painfully. Collectively we will be unprepared. Problems rarely stay “self contained.” There’s a spillover effect. Where possible, people move to flee dire situations looking for better opportunities.

Where have the perceived better opportunities been in recent decades? Migrants have flooded Europe and the United States – regions which for a variety of reasons have failed to impose any limits to growth. Of course the world has experienced movements of people for centuries, but the scale at which migration occurs now is unprecedented, several hundred million moving across national borders in recent decades.

I think of the line, “Water finds its own level,” and wonder where our level is. Will we multiply like yeast, filling all the space, until we have a mass die-off?

Oh, why so negative, some might ask? (Or, per the Joker, “Why so serious?”) We have technology that will meet the demands, these folks will say.

Why? Because the numbers show nothing but persistent growth. Why? Because there’s no history of any true global commitment to sustainability. And, the technological gains we have made (the green revolution in agriculture, for example) have been eroded through more population growth.

While humanity’s predicament looks particularly grim, it is possible (maybe not probable, but possible) to chart another course if we step up to the challenge. To economist Lester Thurow’s comment, low population growth is required to improve quality of life, an idea that gets more traction in some countries than others.

Recently population activist Mark O’Connor threw his hat into Australia’s political realm through the Stable Population Party, stating,

     “Every nation has both a right and responsibility to keep its population in balance with its resources. The notion that you can grow forever is crazy economics.”

More O’Connors are needed.