Showing posts with label population. Show all posts
Showing posts with label population. Show all posts

Saturday, 2 January 2021

Collapse you say? Part 4: growth, overshoot and dieoff

Nature's Ice Sculptures Along Lake Huron

On the rare occasions when the subject of collapse comes up in polite conversation, a kollapsnik like me is liable to get responses like: "Collapse you say? Surely not!" Thus the title of this series of posts. But I've found that responding with "Surely yes!" isn't very effective (as well as sounding rather childish). The pandemic this year (2020) has got some people thinking a bit more, but most still expect things to get back to normal any day now.

So in this series of posts I've been talking about what collapse is and why I think the our civilization has been slowly collapsing for several decades and will continue doing so. This in the hope of laying out the facts clearly enough that just about anyone should be able to recognize the seriousness of the situation.

In the last two posts(Part 2, Part 3), I looked at problems with the inputs to and outputs from our civilization, and pointed out a number of issues, any one of which alone should be cause for great concern. And taken together, well....

Now I think it is time to have a look inside the box labeled "Industrial Civilization". When you look around you from within this civilization, you are confronted with a complex and confusing sight, of which I don't have any sort of complete understanding. But there are some aspects which bear more directly on collapse than others, and I'll have quite a bit to say about them in the next few posts.

The problems we've looked at so far—resource depletion, declining surplus energy, climate change, overshoot and decreasing carrying capacity—all seem to be a result of the ongoing growth of our civilization, both population growth and growth in affluence. So you would think we'd be making a serious effort to get growth under control, maybe even initiate "degrowth", in order to cope with these problems. And yet, over the last few decades economic growth has come to be seen as a necessity. If you paid attention to election speeches, you'd conclude that the most pressing problem we face is maintaining and further stimulating such growth, not preventing it. It seems to me that this obsession with growth is a built in feature (dare we say a fault) of our civilization.

To more clearly understand our impact on the planet—our footprint—we need to review the subjects I touched on at the end of my last post: eco-system services, carrying capacity, and overshoot. Eco-system services are things like breathable air, potable water, a reliable climate and moderate weather, arable soil, grasslands, forests and the animals living on/in them, waters and the fisheries they provide, and so on. And also important, though I neglected to mention it in my last post, is the ability of the eco-system to (within limits) absorb and process our waste products. All these things are available to us free of charge and we simply could not do without them.

It is reasonable to call the rate at which the eco-system can supply those services to us its "carrying capacity". The portion of those services that the human race uses can be called our "footprint"—the impact we have as we walk upon this planet.

According to the Wikipedia article on carrying capacity, credible estimates of carrying capacity range from 4 to 16 billion humans, with a median around 10 billion. The literature I've read on carrying capacity and dieoff typically talks about us currently being at around 165% of the planet's carrying capacity. If such estimates were made when our population was around 7 billion, then the carrying capacity was a little over 4 billion. That's at the low end of the range of estimates, which seems prudent. Using the high or even median estimates would lead us to do nothing in the belief that everything is OK and may well continue to be OK. Instead, we should be setting ourselves up to run well below carrying capacity, allowing us to live on this planet without damaging it and with a comfortable margin to allow for unforeseen circumstances.

Being over carrying capacity is called being in overshoot, and it leads to collapse. Some of the extra over 100% comes from consuming non-renewable resources, and some of it comes from using renewable resources at greater than their replacement rate, so that they too are irreversibly consumed. This means that we are actually reducing the carrying capacity of the planet and digging ourselves into an ever deeper hole. Certainly judging from the resource depletion and pollution (mainly climate change) problems we're currently experiencing, it seems that we are indeed in overshoot, and the condition of the ecosphere is definitely worsening.

If we are to solve the problems caused by our overshoot we need not just to reduce our impact below the current carrying capacity of the planet, but rather to go below the smaller carrying capacity that will be left by the time we get to where we are aiming. Further, since it is a big planet with different conditions in different places, we can't just look at global averages, but must consider impact versus carrying capacity on a region by region basis. This to avoid being fooled if we are lucky enough to live in an area that is not as yet hard hit. In much of Europe and North America, it seems we are currently being fooled.

Our footprint (impact) is expressed in the following equation: I=PAT.

"I" stands for impact, or footprint, which is the product of three factors:

  • "P", which stands for population.
  • "A", which stands for affluence, or consumption of resources.
  • "T", which stands for technology, and is included in the hope that improving technology can reduce our impact

We seem determined to do whatever it takes to increase "I", no matter how negative the results. Is this because of something inherent about human beings, or the way we organize ourselves, or the circumstances we find ourselves in? Or perhaps all three combined together?

In the rest of this post and the following one we'll look at this from the viewpoint of our growing population. In future posts we'll look at the role affluence and technology play in our problems.

But first I think we need to understand something about the mathematics of growth. In cases where the rate of growth is related to the size of what's growing, growth is "exponential". If you chart such growth on a graph, it looks something like this:

Figure 1, The Exponential Function

This is the kind of growth you get with a compound interest savings account, where even if the interest rate stays the same, the balance in the account increases dramatically over time. It is convenient to look at exponent growth in terms of the doubling rate, the amount of time it takes for that bank account to double. A rule of thumb is to divide 70 by the percent growth rate per year, and that gives you the approximate doubling period in years. If you are lucky enough to get 10% interest, your savings will double in 7 years. At 5% interest it takes 14 years to double and at 1% interest, it takes 70 years to double.

What may not be clear from Figure 1 is the degree to which the curve takes off as it moves to the right. Growth is very slow at first until we reach the "knee" of the curve, then it goes right through the roof, so to speak. A great deal has been said about how exponential growth is counter-intuitive for most people. Here is a short (not quite two minutes) YouTube video about the subject. If you have a little more time (11 minutes), this video goes deeper into it.

But in the physical world, growth consumes resources, which are only available at a certain maximum rate and can a only support so large a population. At some point the rate of growth starts to decrease and the curve levels off rather than continuing upwards. So the exponential curve doesn't really give us a very good picture of how growth actually works. For that we need to look at the logistic function.

Figure 2, The Logistic Function

Of course the logistic function assumes a constant supply of whatever it takes to support a population, so that the right side of the curve levels off and stays flat. Again, the real world doesn't exactly work like that. In the real world it is possible to go into overshoot, and over consume resources so that the rate at which the system can supply them is reduced. This results in something like the curve shown below.

Figure 3, Overshoot and Dieoff

The population in this case is of some sort of simple organism with a more or less fixed consumption rate per individual, and a growth rate determined by the availability of food. I have chosen to show the worst case scenario where the population we are considering declines to zero because of decreased carrying capacity and the rest of the ecosystem is so badly damaged by the overshoot that it dies out as well.

Fortunately, this is not necessarily the case—as the population goes into dieoff it eventually goes below even the reduced the carrying capacity of the environment and quits damaging the environment. The environment, if the damage is small enough, may be able to recover, even if the species that was in overshoot doesn't. If it recovers enough before the population under consideration goes extinct, that population may be able to recover as well, something like this:

Figure 4, Overshoot, Dieoff and Recovery

What happens as time progresses off the right end of the graph varies. The population may go into overshoot again, then die off and recover, and this may be repeat on an ongoing basis. Or, at any point along the way, a dieoff could lead to extinction. In any case the idea that there is a "balance of nature" that would cause the population to level out just below the carrying capacity is largely bogus. Things are always changing and don't stay balanced forever, or even for very long.

So now that we've looked at growth in general, we need to look in detail at the growth of the human population of this planet. Because human populations can change their growth rates, their levels of consumption and even the carrying capacity of their environment, this is complex, and I'm going to devote the whole of my next post to the subject. In short, though, based on the ideas of carrying capacity, overshoot and our capacity for growth, I am not in the least dissuaded from my predictions of collapse,"dieoff" in the language we've been using in this post.

This has turned out to be quite a short post, mainly because I have split it in two and saved the slightly longer second half for next time. So, there is room here for a couple of graphics about carrying capacity and ecological footprint.

Figure 5, Biocapacity and Ecological Footprint

This an interesting and possibly misleading graph, which compares the carrying capacity (biocapacity) of various countries with their consumption, on a per capita basis. The units on the vertical axis are "global hectares per capita, Gha".The Wikipedia article on GHA is a short and informative read. Here is one central paragraph:

"Global hectares per person" refers to the amount of production and waste assimilation per person on the planet. In 2012 there were approximately 12.2 billion global hectares of production and waste assimilation, averaging 1.7 global hectares per person. Consumption totaled 20.1 billion global hectares or 2.8 global hectares per person, meaning about 65% more was consumed than produced. This is possible because there are natural reserves all around the globe that function as backup food, material and energy supplies, although only for a relatively short period of time. Due to rapid population growth, these reserves are being depleted at an ever increasing tempo. See Earth Overshoot Day

To understand what I mean by misleading, take a look at Canada, the country where I live. The graph might make it seem that we are doing fine, since we have a large biocapacity compared to our population. but our per capita consumption (ecological footprint) at 7 Gha is among the highest in the world.

Figure 6, Footprint in terms of "Planets"

Another way of looking at footprint is to calculate how many planets like Earth it would take if everyone on Earth today lived like they do in a certain country. As is so often the case, Canada is left out of Figure 6, but a little calculation using the numbers in Figure 5, leads me to believe that if everyone lived like we do in Canada, we'd need around 4.4Earths. I find that quite a sobering idea.


Links to the rest of this series of posts, Collapse, you say?

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Friday, 16 June 2017

Collapse Step by Step, Part 2: End Points

Kincardine Harbour and Lighthouse, June 16, 2017

In a recent post I talked about how we can expect the collapse of our civilization to be slow and bumpy—uneven geographically, unsteady chronologically and unequal socially. But I was deliberately vague about what's going to happen first, where collapse will go from there and where it will end up. I suspect many of my readers found this rather unsatisfying—I know I did. In this and my next few posts I'll be getting down to the "nitty-gritty" details of collapse.

Number one on that list is that collapse is already happening, and has been since the early 1970s, when oil production in the continental United States peaked and America's shiny new world empire began to crumble.

We'll get back to that soon, but today I want to talk about the end point of the process. Or rather, I should say "end points", since I don't expect things will decline to the same level across the whole planet. Allowing for that, where will we be when collapse is complete and the dust has settled? That's hard to say for several reasons.

First, there is no such thing as a "natural state" to return to. Our hunter-gatherer ancestors were not living in harmony with nature, indeed nature doesn't live in harmony with itself. Nature, and human society within it, are dissipative structures—never in balance, relying on inputs of energy and materials to maintain them in a steady state. Death is the only real equilibrium state such structures have access to, and even after death decay continues to change things.

For the last few hundred years, the energy bonanza of fossil fuels has propelled our civilization to hitherto unheard of heights, a "steady" state chiefly characterized by growth. Collapse will entail a significant energy decline as we give up fossil fuels and nuclear fission as energy sources. We'll be left with solar energy, including its indirect forms (biomass, wind and falling water), and in a few locations things like geothermal and tidal energy, to the extent that we have the wherewithal to access them.

The quantity and quality of energy available will determine, among other things, the kind of energy infrastructure that can be built and maintained. And the kind of energy infrastructure we can support will determine the quantity and quality of energy that will be available. When everyone in a group is struggling just to get enough food to stay alive, there aren't enough spare manhours to work on energy projects beyond obtaining food itself, our most basic energy source. But as things periodically get better, a few tinkerers will have time to get some previously abandoned infrastructure working again. So I expect there will be a good deal of bouncing up and down as this dissipative system works its way toward a new, more or less steady state determined by the lower availability of energy. And because there are different amounts of energy and materials available in different areas, they will end up in different states.

Second, climate change also makes it hard to predict what things will be like when the collapse dust settles. There is a significant lag built into climate change and even after we quit adding CO2 to the atmosphere it will take decades at least before the warming process stops and begins to reverse. It will possibly be hundreds or even thousands of years before things reach a new normal. In the meantime, the climate will keep changing and behaving erratically. So it is hard to say which parts of the world and how much of it will be able to support human life. Even the level of energy use and technology in areas where people do live will be effected by changing climate.

Third, social organization will degrade as collapse progresses and do so in chaotic and unpredictable ways.

Having said all this, I am still feeling adventurous and I think there are some things that can be predicted—that are obvious enough that even an old tradesman like me can make them out.

Population

It's my guess that the human population will settle out at around a few hundred million. This may seem odd to many of my readers.

The UN's population experts say that our population will be between 9 and 10 billion by the middle of the century and then, due to the ever spreading demographic transition things will peak out between 10 and 11 billion before the end of the century. But this assumes that we will find a way not just to feed all these people, but to bring them prosperity in order to lower the birth rate. It's nothing but a dream.

The most realistic estimates I read say we are already in overshoot to the tune of 150%—that would mean paring our 7.5 billion back below 5 billion to get out of overshoot. The demise of oil based agriculture and large scale international shipping will reduce the number of people that our planet can support to a significantly lower number, I suspect around 2 billion. But we must also remember that climate change and various other eco-disasters are going to reduce the planet's carrying capacity even further, and thus I say a few hundred million if things go moderately well. I would be surprised to see the population settles out to more than 1 billion and shocked if it was less than 10 million.

There's nothing really special about these numbers—I certainly don't think there is any such thing as an ideal number of people. Like any successful species, we will always tend to maximize our numbers as far as our environment allows. But with a damaged planet and the high quality, easily accessible fossil fuels gone, there will only be so much we can do.

OK, clearly I'm talking about a significant decline in population. Where are all those extra people going to go?

We are going to see further lowering of birth rates in the developed world, especially as the economy continues to contract and people get discouraged as they did in Russia following the collapse of the USSR. Then we'll see rising death rates, first in the developing world and finally everywhere. Things will fall below the new, reduced carrying capacity and then recover, bouncing up and down a few times until a more or less steady state is reached.

Famine, pandemic and war will all contribute to this. But we tend to forget that we are all going to die anyway, at some point. If that schedule gets moved forward somewhat it can make a big difference and not just to the individual. Over a period of generations even small decreases in birth rate or increases in death rate can make for large changes in population.

In some areas, including, but not limited to the Middle East, sub-Saharan Africa and the American Southwest, desertification will continue and eventually take the decline in population all the way to zero. That is not just due to lack of water, but also due to extremely high temperatures, not so much on average but in the form of heat waves.

Similarly, due to rising sea level and more frequent and violent storm surges, much of the area currently near sea level will be submerged and people will be forced to move inland to higher elevations. In developed areas (and there are a great many of them near sea level) every effort will be made to stave off the rising seas, to hang on as long as possible, but due to economic contraction, energy decline and continued rising seas, those effort will eventually fail.

Unreliable weather will make most ways of life more difficult than they are now. It's tempting to say that rural people who are still engaged in various forms of subsistence agriculture will simply carry on as at present. And that will be true, where the climate co-operates. Where it doesn't they too will be forced to migrate to in search of greener pastures.

Some countries import much of their food, and couldn't switch over to growing it even if they desperately needed to. They are faced with a crisis when the price of food goes up and will be faced with an even larger one when oil supply problems make international transportation prohibitively expensive or downright unfeasible.

Migration, whether it is spurred by climate, economics or conflict will be the defining feature of the next few decades and will itself be the source of much conflict. Even the most welcoming of countries will eventually be overwhelmed with refugees, who will back up into ever growing refugee camps behind various choke points. Of course, some will not make it as far as the camps and for some of those who do, the camps will eventually prove to be death traps.

It is also pretty clear to me that large cities with many millions of people, that rely on modern transportation systems to supply them with the necessities of life, are not going to be viable. They will fall apart in various unpleasant ways and we'll end up living in much smaller communities.

Energy

Some of the energy end points here are pretty easy to predict: we won't end up getting any significant amount of energy from fossil fuels and none from nuclear fission. I don't believe we'll ever achieve nuclear fusion as a practical power source, and if we do, we won't hang on to it for long.

Some (chiefly climate change deniers) will point to coal as an energy source with centuries of supply left. But a closer look shows that peak coal is nearer than we think, and much of the remaining coal is of low quality—not a good source of surplus energy. No doubt there will be a surge in coal use as the availability of oil and natural gas diminishes, but then the same thing will happen with coal.

We'll be solar powered again, as we were for all but the last bit of our history and all of our prehistory. And most of that will be solar power in its indirect forms: biomass (including food), wind and falling water. Solar photovoltaics and large electricity generating wind turbines will be beyond the reach of the available technology for almost everyone. Even solar thermal energy will be quite rare because of the amount of glass required. Sure, you can get the kind of thermal energy required for large scale glass making from charcoal or probably even from wood gasification. But if heat is what you need that solar power installation for, it would be better to use the biomass directly instead.

In most areas human and animals muscles, powered by food, will once again will be the main source of mechanical energy. These will be supplemented by wind mills and waterwheels. Only rarely will there been enough fuel of any sort available to burn in heat engines. Burning biomass will be the main source of heat. And overall there will be much less energy available than we have access to today, perhaps by a factor of 10. That's on the average, of course. My background with Ontario's electrical utility leads me to think it may be possible to do much better than this in a some areas, harnessing falling water to generate electricity using fairly simple technology. Such set ups have quite a high EROEI, producing generous amounts of surplus energy. This is what got the province of Ontario off to its start in the late 1800s and early 1900s as Canada's industrial heartland. Admittedly, the thermal energy cost of steel reinforced concrete is such that large dams won't be feasible, but there are quite a number of locations around the world where hydro power can, and frequently has been, developed with relatively small and simple civil engineering projects.

Keeping such projects running or refurbishing them after they have been shut down or abandoned for a while will be much easier than the development process that went on in the 1800s.

Technology

When people hear about my interest in collapse, they frequently ask, "How far down do you think we'll go?" They are thinking in the sense of what historical level of development will we descend to.

But it is overly simplistic to say that we'll "go back" to a certain period in the past.

Things have changed since then and you simply can't go back. The environment in particular has been damaged in ways that would make many historical lifestyles unfeasible. There is much to be said for the hunter/gatherer lifestyle, for instance, but it requires a high level of skill and detailed knowledge of the area one is living in, things that very, very few of us have or could learn quickly if we suddenly needed them. And stocks of wild game and food plants have been depleted so much in most areas that hunting and gathering simply isn't feasible.

On the other hand, unlike our ancestors, we already know that a great many things are possible. Even if we find them temporarily beyond our reach, re-acquiring them will be much easier than developing them from scratch was in the first place. Where collapse has been fairly complete it will still be possible to salvage many useful things—knowledge, tools and materials. Where collapse is less devastating we'll keep many things working for a long time even if we've lost the ability to recreate them from scratch. And because our population will be much lower, there will be a great deal of left over stuff per capita and, I suspect, a brisk business in refurbishing and repurposing that stuff.

Remember, I've been saying I expect a slow collapse, taking several decades. That's slow compared to what some expect to happen, but pretty quick if you're think in terms of, for example, how long steel exposed to the elements takes to turn to rust. I've heard people saying that in twenty years after a fast collapse all the iron on the planet will have rusted away to nothing and survivors would be using stone tools. From my own personal experience with farm machinery abandoned in the open, I can say that even after fifty years all that has happened is the formation of a patina of rust on any part thicker than a few millimeters. Unprotected sheet metal goes fairly fast, but thicker sections are more durable. Since people will start collecting scrap metal and storing it out of the weather, it seems clear to me that our civilization will leave a legacy of refined metals that should supply post-collapse metal workers with most of what they need for the next few centuries.

So, we'll see some strange mixtures of different technological levels. I expect we'll see even the few remaining post-collapse hunter/gathers using tools made of iron instead of stone.

The limiting factor will be energy. The level of technology that can be supported is determined by the decisions you make about what to do with the surplus energy you have available to you. Note that's not energy, but surplus energy. Problems with low quality hydrocarbons, diffuse and intermittent sunlight, unpredictable wind and so forth mean that we'll have much less surplus energy than we have today. Given the unpredictable climate and weather that we'll be coping with, we'll probably make some fairly conservative decisions—a full belly comes first, especially if you are working hard, and most of us will be.

But once we have electricity, all sorts of manufacturing possibilities open up. Decisions will have to be made about how much of a society's available surplus should be put into setting up the infrastructure necessary to produce electricity and what kind of manufacturing to pursue. Many of these areas where hydroelectric power is available may be able to retain a level of technology roughly equivalent to the early 1900s, for a few million people all told.

Some will no doubt be surprised by what they see as my overly optimistic outlook. There is a large part of our population for whom most technology is essentially magic—they just have no idea how it works or how to make it work if it was broken and they had to fix it on their own. For them, moving down to anything short of our current level of technology is a total collapse. When things start to break down these folk will be out of luck.

But there are many other people who do have a pretty good grasp of how one or more areas of technology work and how to keep them working. As long as you don't have your heart set on the latest high tech toys, it really isn't that hard.

Do I think anyone will be able to hang onto or recover the ability to manufacture semiconductors, computers and possibly even an internet of some sort? The kind of worldwide manufacturing network we have today is not absolutely necessary to attain to scaled down versions of this sort of technology. But I think it is fair to say that it will be rare if attainable at all, and concentrating on this sort of technology will probably prove to be a mistake.

What we'll need to adopt is "appropriate tech"—technology that is small-scale, decentralized, labor-intensive instead of energy intensive, energy-efficient, environmentally sound, and locally autonomous (not critically dependent on materials or tools that cannot be made or salvaged locally).

"Local" and "decentralized" come up in this discussion because transportation without fossil fuels will be much more arduous than it is today.

There are a number of other technology related areas that are big enough subjects for another post and will have to wait until then:

  • How will we manage to feed ourselves when fossil fuel based agriculture is no longer possible? There is no doubt in my mind that, with a sufficiently small number of people to feed, this will be possible.
  • What will be the future of medicine? One thing I am sure of is that even though many people will turn to alternative medicines, they will not be any more effective than they ever have been. In other words, not at all.
  • Genetic engineering has the potential to be very useful in the kind of future that lies ahead of us. I know, I've said this before. It's soon time I explained what I mean and why I am not afraid of genetically engineered organism that are intended to be beneficial. Coming soon in another post.... Of course, there is also the possibility that GE will be weaponized, and that's another story altogether.

Many people are concerned about the legacy of toxic hazards (chemical, biological and nuclear) that modern technology is leaving to future generations. This is mainly a result of fear and misinformation, which often takes the form of a monotonic view of toxicity. That is, the fear that if something is toxic in large doses, it will eventually prove to be toxic in even the tiniest doses, given long enough exposure. The scientific consensus simply doesn't support this, telling us instead that the dose determines the poison. Many things people are afraid of, including radiation and pesticides, are quite harmless in small doses and the levels allowed by current regulations include a ridiculously large margin for safety.

Social Organization

In many ways the level of social organization retained during a collapse is a better indicator of the degree of collapse than the level of technology.

I think it is clear that there will be much less organization, and that it will be in simpler in nature and less centralized. Another major defining feature of the years ahead (along with migration) will be the breakup of various political and economic federations, until the remaining political entities are small enough that they can hope to work with the existing transportation, communication and information infrastructure and the limited energy available to power it.

Many writers, when talking about collapse, fall into pipe dreams about their favorite political and social systems rising to a higher level of prominence that they currently enjoy, and the ideologies that they oppose falling on hard times. I find this quite improbable.

There will be a greater degree of isolation between communities than we have today and a lack of the wherewithal for these communities to force their ideas on others. Because of this, "dissensus" will be easier to do than it is today and many different approaches will be tried. This is a good thing—there is a chance that at least some of these approaches will be successful adaptations to the new conditions.

Having said all this about the end points of collapse, I should make it clear that the paths we'll take to get there are anything but straightforward—they will have some interesting twists and turns that I think most people aren't expecting. That will be a recurring theme in my next few posts.


Links to the rest of this series of posts:
Political Realities / Collapse Step by Step / The Bumpy Road Down

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