“The future ain’t what it used to be.”
There’s no doubt that an ever-increasing global population plays a big part in global warming and climate change. More people means more land to live on, more land for crops, and more livestock for food. Clearing all this land and the construction, agriculture and livestock that go along with it generate a lot of greenhouse gas emissions. As the global population increases and as technology continues to progress with populations either living according to first-world standards or at least trying to, the emissions per person steadily increase as well.
According to the United Nations, on October 31, 2011 we reached a global population of seven billion people and it’s currently estimated that we are fast approaching 7.5 billion less than six years later. With more births than deaths, the number continues to climb. Our species has had many ups and downs in population over the centuries, but ever since the plague finished doing its damage around 1350—leaving us with about 370 million human beings at that point—our numbers have been steadily rising. Better sanitation, antibiotics, vaccination, and modern medicine (especially pertaining to childbirth) have all led to less premature deaths than we used to experience. Before modern medicine, a couple needed to plan for about five children simply to keep the population count neutral. Those days are long gone.
And slowly but surely, women’s rights are steadily improving around the world. There is certainly room for improvement in many parts of the globe, but ensuring that women are educated and able to be part of the workforce, and that they have control over their own bodies with respect to family planning have contributed substantially toward the steady decline in birth rates seen all over the world in the last fifty years. Only the poorest war-torn nations continue to have higher birth rates, in part to offset the higher mortality rates those countries still continue to experience.
Since birth rates are declining, might we ever expect to reach a plateau in the rising global population? Even if the number of people continued to climb indefinitely, a plateau would be forced on us at some point. Resources like food grow linearly, but populations grow exponentially. It was this observation by the economist Thomas Malthus that helped Charles Darwin formulate his theory of evolution. Since consumers are in competition for these limited resources, the fittest tend to survive. Despite us living on a very large planet, Earth’s resources are undoubtedly limited.
But the United Nations Population Division has predicted we will reach a plateau even if one isn’t forced on us by limited resources. By 2050 it’s anticipated our population will likely reach a peak of about ten billion people. The math here is actually pretty easy to understand so you can see how they arrived at that number.
Right now there are roughly two billion children alive under the age of 15 and that number isn’t expected to change very much in coming years because the birth rate is anticipated to remain close to where it is at present. There are another two billion people alive between the ages of 15 and 30. It’s closer to one billion people alive between the ages of 30 and 45, one billion between 46 and 60, and one billion over the age of 60. It’s easy to see why the population is climbing because there are two billion people in the 0-15 age group and they are being replenished at a steady rate, but only one billion people aged 60 and older that are approaching the end of their lives and dying.
With time, the one billion in the 30 to 45 age group will be replaced by the two billion in the 15 to 30 group. Another fifteen years later, they’ll move into the 45 to 60 group, and so on. If every year the base group of children on the planet remains steady at two billion, then each of the age groups listed will eventually have about two billion people in them. Five groups of two billion people each makes for a total of about ten billion.
Obviously there are a lot of assumptions being made here, but it seems reasonable for us as a species to plan for a growing population of perhaps ten billion or so in the coming decades. Those people need energy, and it would be so much better if we could give it to them with renewable sources contributing little or no emissions rather than continuing to focus on fossil fuels. We’re already past peak oil in many sources on the planet, looking to use less accesible sources now such as offshore drilling or the Alberta tar sands. And mining for coal is reaching absurd levels, removing mountaintops in some instances. (And don’t even get me started on fracking!)
If we could find a way to cope with ten billion people on this planet and provide them with the standards of living that we all need (although not necessarily the standards some more excessive and conspicuous individuals might want), then we might—just might—have a chance to make it through this global challenge.
That’s the way we need to start thinking about tackling the problems our planet is facing. Looking to where we’re headed in the future and planning for it, rather than simply continuing on with business-as-usual because it’s easier and more profitable for a select few in the present day.
Future generations will never forgive us if we don’t.