Wither Human Population?

(This is a repost of an original essay here.)

Tue, 02/09/2010 - 06:15 — Greyzone

From the February 6, 2010 discussion at TAE, people were asking about timelines and population targets. This post is an attempt to answer that question in slightly more detail. An in-depth look at this topic could cover multiple volumes.

Ecologically, when you see an overshoot situation, the lower end of dieoff tends to be over 70% of total population. But homo sapiens is in extreme overshoot. Where we are on the curve is like a test tube full of yeast right before the crash. Extreme overshoots very typically see dieoffs in the range of 90%-99%.

Because of weapon systems, resource scarcity, arable land issues, water issues, etc., I expect the world in aggregate will experience something close to a 96% dieoff. That would leave about 300 million living worldwide, which is still pretty far over the average population of homo sapiens for most of out 200,000 years of history. Prior to agriculture global hunter-gatherer population was probably between 10-20 million.

I expect this dieoff to occur in steps over the next 100 to 120 years. If the Greater Depression persists as long as a decade, we may finally see human population stabilize and then begin to drop as early as 2020. If the Greater Depression ends sooner, we may still see total population push towards the 8 billion mark by 2040 and then begin its turn.

But population does not exist in a vacuum. This population was made possible by industrial civilization, which itself was made possible by massive resource extraction and destruction of biosphere all around the world. As infrastructure becomes too expensive to maintain, population that is dependent on that infrastructure is likely to begin dieing off.

At TAE Zander asked specifically about Scotland. Scotland historically had a population under 1 million for centuries because that is all that the land there could sustain. Sustaining 5 million is going to be hard. On the plus side, rising rates of infant mortality plus deaths of older people over the next 40 years is likely to reduce Scotland's population to under 3 million and perhaps under 2.5, which means the subsequent downturn to 1 million over the following 80-90 years should not be nearly so harsh as in the rest of the world.

In the US, for example, population is likely to continue rising even in the face of the Greater Depression, just more slowly than before. Yet the US is far more dependent on its technological systems than, say, Mexico. A large part of the US west of the Mississippi is only habitable at current densities due to a multitude of technologically based water systems. Los Angeles, for example, housed only a few thousand residents in a harsh desert landscape prior to redirecting water flows from the mountains to LA. When the systems supporting those water flows begin to fail, place like Los Angeles will become deathtraps for millions.

In fact, early migration in the US during the infrastructure collapse phase is likely to be towards the Great Lakes, one of the largest collections of freshwater in the world. Ironically, that migration is likely to result in the ecological death of those same lakes, ultimately killing even more people.

Barring climate change, some parts of the US west of the Mississippi should be able to sustain agricultural communities but population densities in those places is also still too high for the current population. Western Washington and Oregon could do better than much of the rest of the western US, but the same reasons that give those areas an advantage are likely to attract excess population, resulting in worse overshoot locally. Eastern Texas and Arkansas are not bad but in such close proximity to high population urban centers that they are likely to be destroyed as a side effect of the collapse of those same urban centers.

Regarding Africa, I expect Africa will see massive dieoff as well. Much of Africa's population density is enabled by industrial civilization, even if it's not as nice as North America or Europe. Hominid hunter-gatherer populations in central Africa over the last few million years have never amounted to more than a few million at the very best and mostly in the few hundred thousand typically. Africa's population may not fall quite that far, but it will make a good run at it.

The ecological disaster around you is an artifact of "modern" capitalist, growth-oriented, debt-centric civilization. I place that word "modern" in quotes because I tend to favor free markets myself, but on a far more local level and without resorting to debt based infinite growth systems. Historically humans have avoided debt based systems and instead financed any growth when needed from savings. And growth was not always the primary goal either.

But now we come to the crossroads where debt-based civilization can no longer sustain itself. And in reaching this crossroads, we find that not only is the financial system going down, but the effects from the financial system are going to take down large segments of the biosphere with it.

The future for human survivors is going to largely be a scavenger's future, possibly for several centuries. We will lack the infrastructure to deploy technologies to recover the last of the oil, underneath 15,000 feet of water and another 10,000-20,000 feet of undersea salt dome. Instead, survivors will be forced to get along on what they can create within their local communities and much of that will be driven by what can successfully be scavenged from the wreckage of industrial civilization.

The most typical dieoff I've seen given population curves that look as ridiculous as our own is in the 98-99% range. In choosing a 96% dieoff I admit to holding some small hope that a few humans will manage to adapt to changing circumstances faster than expected. The time frame is the same as for any dieoff within a population that is in extreme overshoot, from 1 to 4 generations total.

To put this in context, during WWII, when global population was under 2 billion and we killed over 200 million human beings, global population still rose. Now think about what a shrinking population means and the kind of world that means around you. Any single one of you who believes that you have no duty to defend your own lives by whatever means possible may as well just line up to be slaughtered when it begins. There will be no government to protect you. You will find yourselves once again in the same situation that mankind has been in for most of its entire existence - dependent on self, family, and tribe for survival. And nothing you can do is going to stop this from happening to you, your children, and/or your grandchildren.