population explosion

According to the US census bureau, there were an estimated 1 million people on the planet in 10,000BC. Apparently since that time the human population has increased continuously until the present day. That seems a bit suspicious to me, but so be it. The rate of growth has also increased continuously and there is only one period of significant deceleration. That happened in the 1,000 year window centered around year 1.

In 10,000BC , it took an estimated 1,000 years or 10 centuries for the population to double. There are some minor fluctuations in the estimates but these are probably due to the guesswork involved. By 1,000BC we have an estimated 50 million individuals roaming around. Then the population suddenly starts doubling in approximately 500 years or five centuries. By year 1 we have 170 million people or just 30 million shy of the projected 200 million. And here we see the only noticeable drop ever. It takes another 600 years for the population to reach 200 million.

Starting around 600 the rates accelerate once again. 650 years later we have 400M. Then 550 years later we have 800M and 105 years after that we have 1,600M or 1.6 billion. We are now in 1905 and the doubling rate keeps shrinking. 65 more years until we hit 3.2 billion, then 40 years until we hit 6.4. Luckily, the Census predicts that it will now take 44 years (a whopping 4 extra) for the rate to grow by 50%. You could say, whew, finally!

So what is behind this incredible explosion? It appears that two factors were key. Both involve access to new sources of power and energy. One is the switch from manual and horse-driven labor to machinery and the second is the discovery and wide-spread use of oil. There is little doubt that the so-called "green" revolution is responsible for the biggest boost of all. Clearly what matters most is how much food we can produce. More food equals more people.

Unfortunately our food production system is unsustainable in the long run. It is a system whereby we input almost 10 times as much energy -from oil- as we get out. We get the 10 fold extra by burning through an energy source that took hundreds of millions of years to accumulate. And we are going through it in 100's of years. Clearly something is out of whack here.

When the oil industry gleefully reassures us that we are many decades away from peak oil, we may end up feeling relief. The gas-guzzler crowds feel vindicated that once again, the doomsday prophets have failed. But ask yourself this simple question. If we are decades (or even centuries for that matter) away from reaching peak oil, shouldn't we be scared shitless? We are talking about a resource that took 100's of millions of years to get to its current state, and we have been using it for what? 100 years? And we are within a few tens or hundreds of years of depletion?

One thing is for sure, the population graph won't level off nicely like the US census predicts. It may soon start looking like the stock market of the year 2,000. Except that this time around it won't be virtual or paper losses on the way down. It will be real people.