Brace for Peak Impact

Image by Paul Brennan from Pixabay

Guilty as charged: my recent postings have been all about human population and when it might peak. I don’t mean to be a bore, but it’s an important topic connected to planetary limits, human impacts, ecological health, and the appealing prospect that a near-term peak may offer an earlier off-ramp for modernity. In the past, I have stressed the point (in a blog post from 2013 and later in a textbook chapter) that population per se isn’t the phenomenon of greatest concern, but its multiplication by resource usage. It’s the combination that launches us over the ecological cliff edge, commonly expressed by the I=PAT formula for impact on the planet.

In this post, I belatedly take my own advice and re-frame the population investigation in resource terms. Now that I have a demographic tool, I can ask questions relating to when we might hit peak power as a civilization. I use power (rate of energy use) as a proxy for all manner of resource dependencies, as energy usage correlates strongly with materials use and ecological impact. Plus, it is a readily-available measure.

So, given various assumptions about how fertility rates evolve regionally, and factoring in different models for regional survival rates and migration, when might we expect global resource use to peak and begin a decline? In tandem with this event, we might correspondingly expect peak industrial output, and peak rate of (accumulating) damage to ecological health—which includes our own health. In the U.N.’s standard demographic model, population does not peak until 2086 at 10.4 billion—largely bolstered by population growth in Africa, which the U.N. parameters indicate will climb to 4 billion by 2130 (we’ll see…). But, since Africa is by far the region with the lowest per-capita consumption, declines elsewhere could more than offset Africa’s population increases in terms of resource burden.

Enough speculation: let’s unleash the model and see what happens.

Regional Power

Our exercise starts with the following table that parallels Table 3.5 in Chapter 3 of my textbook:

Region Pop (B) kW/cap Power (TW)
Africa 1.49 0.5 0.8
Asia 4.79 1.8 8.6
Europe 0.74 4.9 3.6
Latin 0.67 2.2 1.5
N. A. 0.38 9.9 3.8
Oceania 0.05 5.4 0.3
World 8.12 2.3 18.5

Multiplying population (in billions) by the power per capita (in kW) gives terawatts (TW) of power. For the whole world, it comes to about 18.5 TW. [Note that the American regions in this table are defined differently than the continental divide employed in the textbook, in that “Latin” stands for Latin America (including Mexico) and the Caribbean, while Northern America is primarily the U.S. and Canada (see the Geographic Regions tab here for exact definitions).]

For simplicity, I hold the per-capita power usage at these values for the entire simulation. This isn’t insane, as the plot below shows global per-capita fossil fuel use being relatively flat since 1970 (right-hand plot; suggestive red curve), in contrast to the ever-climbing total power, at left. In truth, per-capita energy will more likely decline as fossil fuel availability wanes and other (associated) disruptions arise, possibly pulling the moment of peak power even sooner than the following projections suggest. Additionally, net energy peaks sooner than total energy when extraction/processing efficiency declines as easy resources are consumed first.

Fossil fuel use history and per-capita rate. It’s stacked, so that gas is 0.5 kW per person, not 2 kW. The red curve at right shows a relatively stable per-capita power since 1970.  The surge around 2005 is largely due to a major coal increase in China.

Anyway, holding per capita power flat is fine for the purposes of this exploration, since accuracy is unobtainable in such exercises.  We just want to provide some window into the situation, differentiating various outcomes at the decade scale.

U.N. Case

Let’s start with the vanilla U.N. assumptions and resulting projection. This is the one that peaks in 2086 at 10.4 billion people, with Africa still on the rise until about 2130. In the tables that follow, I list for each region (and the whole world) the year of peak power consumption and the associated value in terawatts.

Africa Asia Europe Latin N.A. Oceania World
2130 2056 2022 2055 2094 2109 2061
2.0 TW 9.6 TW 3.7 TW 1.6 TW 4.4 TW 0.4 TW 20.5 TW

So, while global population peaks in 2086 in this scenario, energy consumption peaks 25 years earlier. This is a convincing illustration that the two things have substantially different timing. Incidentally, for each region (but not the world as a whole), the year listed for peak power also coincides with peak population, as a single per-capita number is applied for the whole region.

U.N. with Flat Survival

Just as we freeze power per capita, we can freeze survival rates at today’s level. This is equivalent to saying that regional life expectancy neither rises nor falls into the future (keeping in mind that post-peak, the model becomes garbage as lots of things change). For reference, pre-COVID life expectancy in the U.S. was remarkably flat from 2010–2019 (peak was 2014; see plot below).

Data from the CDC:

COVID contributed to a significant dip, and the 2022 number is on a par with what it was 18 years earlier in 2004. In other words, a monotonic increase in life expectancy through the year 2100—as modeled by the U.N.—already seems broken and is not guaranteed to materialize. In perhaps yet another disconnect, the 2022 UN demographic projection model expects U.S. life expectancy to break 80 in 2025—somehow. Anyway, here’s what happens in the flat-survival scenario:

Africa Asia Europe Latin N.A. Oceania World
2100 2047 2021 2045 2050 2134 2048
1.6 TW 9.2 TW 3.7 TW 1.6 TW 4.0 TW 0.4 TW 19.7 TW

Now peak power pulls back another 13 years to occur before mid-century: not far away.

My TFR and Flat Survival

I have serious qualms about the U.N.’s apparent denial of nearly-ubiquitous downward trends in total fertility rate (TFR) over the last decade, as I first expressed here and further dissected here. The basic disconnect is that many countries around the world are exhibiting low and declining TFRs, but the U.N. model repeatedly fails to capture or anticipate this trend, imagining instead a quick rebound to higher (historically “normal”) TFR values that persistently fail to materialize in projection after projection as the years roll by and the declines stubbornly continue. Using the alternate TFR model I developed (introduced here), and keeping the “flat” survival model (locking at 2023 rates), this is the emerging story:

Africa Asia Europe Latin N.A. Oceania World
2075 2036 2021 2039 2036 2071 2036
1.2 TW 8.8 TW 3.7 TW 1.5 TW 3.9 TW 0.3 TW 19.0 TW

Now we’re just 12 years out from the global peak! Africa peaks late-century, still, but at a small total power that does little to shift the larger trend. Incidentally, using the U.N. model for monotonically increasing survival rates in combination with my alternate TFR model produces a peak in 2044.

My TFR and Reverse Survival

In a declining energy scenario and the attendant economic convulsions, it could make more sense to imagine a reversal of life expectancy as advanced medical care becomes less prevalent. The slow reversal model I employ is a mirror image, so that ten years from now it’s as it was ten years ago, etc.  Hey—as displayed above, life expectancy peaked in the U.S. in 2014 and is now where it was in 2004, so we’re already experiencing something qualitatively similar to this model.  Reflecting the U.N. survival models around the year 2023, we get this development:

Africa Asia Europe Latin N.A. Oceania World
2064 2034 2021 2035 2037 2055 2034
1.1 TW 8.8 TW 3.7 TW 1.5 TW 3.9 TW 0.3 TW 19.0 TW

The change from the previous case is not dramatic, because peak power is so close-at-hand that medical conditions don’t change drastically from the “flat” model in ten years’ time. Still, we’re down to a decade away from now!  The peak power in the last two cases is only a few percent higher than what we pump out today, so that life right now could pretty-much be what the peak feels like.  It’s that odd moment near the crest of the roller coaster, when the basic contours of the experience are about to change entirely.

As an aside, if you noticed and are concerned by the strange result that Northern America moves one year later by reversing the trend (and other counter-intuitive changes in earlier cases), it’s due to the fact that the “survival” model I extracted from U.N. projections simultaneously accounts for migration, so that the reversal in this case reflects an uptick in (past) immigration.

Although plots of these model results aren’t ridiculously instructive, let’s have one anyway, including regional contributions.  Dominant Asia largely sets the pace, as can also be appreciated in some of the tables above.

Global and regional energy demand in the model projection.

Actually, this plot just gave me a bit of Déjà Vu. Within the first month of starting Do the Math, I put up a post pointing out that data on U.S. energy usage was starting to roll under the exponential curve, but that it was too early to tell whether it was heading for leveling-out or powering-down. The curve above (for the world) is firmly in the power-down camp based on demographic projections. This isn’t a post on peak oil, but in some ways amounts to the same phenomenon of declining power, by a different mechanism: not one of the scenarios I had considered for bringing about the peak of fossil fuel use.  The real world will surprise you like that!

Africa Rising

While most of the world has TFR falling faster than the U.N. models reflect, this may not be true for Africa. What if Africa is recalcitrant in its fertility decline, dropping more sluggishly than the U.N. projections? Setting aside biophysically-rooted skepticism I expressed last week, let’s see how the story changes if we keep the alternate TFR model for most of the world, but allow fertility decline in Africa to be slower than the UN case, as in the following plot.

Modified TFR with slow Africa: solid is data; dashed used for the model; dotted is U.N. projections.

Africa Asia Europe Latin N.A. Oceania World
2082 2034 2021 2035 2037 2055 2034
1.5 TW 8.8 TW 3.7 TW 1.5 TW 3.9 TW 0.3 TW 19.0 TW

This change results in Africa’s population peak moving out 18 years from the previous scenario and adding another 0.75 billion people to its peak (to 2.9 billion in this reversing-survival case). Meanwhile, the global population peak only moves from 2040 to 2043 (not shown in tables).  But the global peak in power did not move in year or magnitude. That’s because Africa has the smallest per-capita resource footprint of all the regions—by a significant amount—so that prolonged growth on its part does not hold much sway over the global story in terms of resource peak.

Power, not the People!

The main point of all this is that concern about population growth tends to be motivated by concern over the impacts on Earth and/or resource availability—not over the raw number of people. In this context, the date of peak-people-number may turn out to be less significant than the date of peak rate of resource exploitation. Some of the scenarios above put this within 10 years! I’m surprised. Are you surprised?

Because energy is a decent proxy for the scale of the global economy: extractive activities, industrial output, transportation, agricultural production, construction—and all the other things we do with energy—a global peak in power output likely corresponds to a global peak in the industrial scale of modernity and its economy. Wow. And that may happen in the next decade. Hold on to your hats!

Let’s throw up again a plot of the doubled-resources run from the Limits to Growth 30-year update (best match to data thus far):

World3 model from the Limits to Growth 30 year update.

I wasn’t at all trying to match this result, but damn! Looks like a peak in industrial output and population around 2040. Food per capita is at an all-time high about now, in their model. By 2050, we should know if the model has anything to it. That’s a “short” 25 years from now, but it must have seemed a distant eternity beyond comprehension in 1972. An important distinction between Limits to Growth and demographic projections: LtG is a systems model, tracking a whole host of fundamental drivers.  Demographic models tend to be narrow extrapolations based on past trends and some guesswork (idealization) as to future evolution of trends, but not attempting to dynamically model the entire interconnected system.

Is Post-Peak Bad News?

John Michael Greer offers context on what declining population could mean in a recent essay titled An Unfamiliar World. Economic growth has heretofore been entirely in the context of growing population, and not by coincidence. More people translates to more demand, more jobs, more houses, more retail, more cars, more energy, and all the rest. Fewer people translates to…

This must seem like dire news to an economist, but it may be just what the living world (to which we belong!) needs to move closer to balance and functionality. Bad news for Team Cancer, but good news for the whole organism—Team Life. And to be clear, I’m not calling humans the cancer and advocating eradication. Before being afflicted with cancerous cultural norms, humans operated within an ecological context. Pancreatic cancer does not mean that the pancreas is inherently bad—just that an unfortunate development changed its essential character and how it interacts with the whole organism. Note that a successful cancer is bad news even for itself, as it dies upon killing its host, without ever passing its genius to a future version of itself. The more “successful” it is, the worse the outcome—just as for modernity. Let’s rediscover what it is to be non-cancerous humans as integral actors in “right relationship” with the rest of the community of life.  Everyone would be healthier for it.

Our present cancerous economy is not geared to handle the switch to a decline phase gracefully. Investment relies on the notion that tomorrow will be bigger than today. What does a generations-long contraction scenario look like to investors? The mattress starts to look pretty good as a place to stash cash. The question—whose answer we can’t know yet—is: how quickly and turbulently will the economic chemotherapy proceed, and can the organism survive the treatment or is the cancer too invasively suffused throughout? One ray of hope here is that each newborn is not yet infected with cultural maladies, so that real change can begin as soon as the culture recognizes its folly and tries something different—allowing the irredeemably afflicted members to fade out in a natural, slow progression.

The Stadium

At the risk of inducing metaphorical whiplash, I have also used some form of the following metaphor to paint the picture as I previously imagined it developing: Crowds flock to fill a stadium to witness a spectacular event. They aren’t sure exactly what it is they’re going to see, but word-of-mouth promises that it will be amazing. It turns out that the grand spectacle is the collapse of the stadium—entirely due to the size of the gathered crowd.

That’s how I perceived the tragic irony of having the most-ever people on the planet suffer the worst-ever event: an event brought on precisely because of so many people: a self-fulfilling tragedy that maximizes total suffering as if by dastardly design. I saw it as an unwitting and inevitable trap. Population would heedlessly grow until it hit a wall and broke its nose. And the wall.

In light of the potential for an early peak due to rapid fertility declines underway in the resource-hogging (“developed”) world, I wish to modify the stadium metaphor: fewer people came than expected, and began thinning out before triggering utter collapse.

Now, the stadium (modernity) was never built on principles of sustainability, so it inevitably crumbles anyway, and it still has substantial crowds putting a load on it, at great risk to themselves and others. But instead of wholesale catastrophic collapse that takes almost everyone down with it, smaller-scale asynchronous crumblings are confined to regions. Questions: Is it still tragic and does it still involve human suffering of an unprecedented scale? Very probably: that can’t be helped at this point, unfortunately. Is it as bad as a full-scale collapse brought on by unrelenting growth of the crowd? Surely not. I’ll take whatever sliver of good news I can get!

I should point out that the mere presence of the stadium has crushed and extinguished many species who did nothing wrong, but didn’t stand a chance. Going forward, the stadium will continue to harm others (and humans) both by its existence and during the uncooperative process of its crumbling. In other words, humans are not the only ones to suffer for its being built and for its self-destruction. Moreover, it makes no sense to pretend that harm to the community of life does not also harm humans—being that we are a part of the community, not separate from it.

Let’s face it: the stadium was never a good idea. It’s been really amazing and cool in a number of ways, but never “of this world” in the sense that it had no contextual support from ecological, biophysical, or evolutionary history, and thus was never vetted for sustainability (long-term success). It’s a short-lived stunt.

The fortunate development could be that ticket sales wane as youngsters already brought into the stadium see the cracks and decide not to invite more youngsters—ignoring the panicked old-guard who hold unshakable faith that this grand event is going to turn out to be amazing in a spectacularly good way if only the young folks would share their faith and invite more people.  Meanwhile, perhaps some within the stadium will quietly find the exits and others will manage to survive the Great Crumbling to swear off stadium life forever more.

Bonus: Video!

I made a video on the topic!

Views: 4357

28 thoughts on “Brace for Peak Impact

  1. At first glance, a simplistic notion: How can people of whatever grouping you have used, feed themselves? The "Limits to Growth" chart shows peak food now, and Africa imports about 80% of the food needed. The broader systems analyses would seem, then, to suggest that population "growth" will not go the ways described. Further, to suggest that "surplus" human beings [common term used too readily to avoid purposeful analyses] will of course migrate to Europe and North America merely because they are "surplus" in their native regions neglects the facts stated by so many migrant persons that they have no prospects in their native countries for both political and environmental disparagement that they need to leave behind or perish.
    So much more complicated indeed!

  2. What would you put the odds of the stadium lasting for another century or two, or even for another few centuries (still an extremely short period of time, as you've often pointed out)? What you put the odds of the crowd continuing to grow – perhaps after first shrinking, or perhaps not – during that time?

    • Well, I don't know. Perhaps it's not a single answer. How long did the Colosseum in Rome last? The answer is ill-defined, as some of it still stands today. This seems like a credible path for the modernity stadium as well: large sections will crumble at different times, while some remnants will be very stubborn.

      As for a turnaround? Certainly it seems that at some point in the future we'll see some sort of rebound (extinction otherwise). But if a fossil fuel infrastructure is not preserved through the reduction phase, I wouldn't bet on it rising to anything close to today's population. Birth rates may well go up a lot, but perhaps hand-in-hand will be infant mortality and pared-down survival rates. So hard to say, though.

      • Interesting. Would it be too much of me to ask if you could dedicate a blog post to outlining scenarios showing what, within the realm of plausibility, the actual peak population could be, or the actual maximum maintenance of the 'stadium' in large parts of the world could be. Forgive me if you've already done this elsewhere – I've read many of your posts and much of your book, but not all. Could we plausibly ever hit 20 billion people, for example? Could we plausibly ever continue modernity for billions of people for another several centuries, for example?

        • I don't believe I can satisfy on this front, other than to say that the peak could plausibly be as low as 8.5 billion, and (in my mind) likely below 9 billion (see for details, and subsequent posts). I don't think of the stadium as maintainable in the long run, therefore to be abandoned. I suppose it is conceivable that some pared-down modernity could persist for centuries (I can't rule it out), but it seems implausible and also probably bad news for the sixth mass extinction (therefore us).

  3. It's hard to see how this interconnected global economy and civilisation can have some parts crumbling whilst others go on for decades longer. Modernity is only as strong as its weakest link, surely?

    However, I don't think there is any evidence for hope that humans will discover a simpler, less impactful way (mind you, at 8-10 billion, "less impactful" would have to be zero impact). If some alien observers were looking at us, they would see humans acting in the same way as all other species, accessing/consuming resources as quickly as they can. If humans could somehow constrain their consumption then those aliens would see an anomaly in one species and wonder what happened. Whether humans could willingly reduce that consumption to a level that we humans could describe as "sustainable" (able to be sustained indefinitely) seems sadly in doubt.

  4. Since you employ John Michael Greer, who is profound in his analyses on population dynamics, sustainability, history of civlizations, in his esoteric discussion, the Stadium isn't "a bad idea" as such, but just a necessary phase this world goes through.

    In our individual human view we may see the suffering and destruction of our civilization, in the deep time look on the world, it is another disruptive event, there have been many, making way for a new world.

    I notice in all these 20th/21th century books the frequent use of "we" as humanity, as kind of a universal human society, and "we must" as an idea of humanity acting in lockstep, solving problems on a grand scale.

    A feature of globalisation. Given that pretty much all civilizations deemed themselves center of the universe with a universal morality, the whole of humanity has never acted like a bee hive, rather a dynamic swarm of societies and sub-societies, down to the individual and small groups like families and local communities.

    I can see nothing like a "we" here.

    In an esoteric view, the wisdom to see beyond one's own instincts is in any way a logical step in our spiritual evolution, always concerning some of the present humans alive, but never the majority.

    Thus what we are seeing is individually for us a tragedy, a catastrophe, something so foreseeable yet unstoppable, but seen from deep time, a necessity in an ever changing cosmos, that was never meant to be paradise, never meant to be static and blissfully so.

    That is reserved for eternity and infinity, in an occult reading, the infinite source of all finite existence.

    John Michael Greer does not stop there, he gives a lot of practical advice of how to deal with a time like ours as an individual, both mentally and in terms of actual actions, mostly concerning down-scaling to a more humble existence for still aflluent westerners like me.

    He offers a lot of consolation and in a way, optimism despite the obvious vanity of existence.

    In this respect and as I see it, wishing for a global society to reach a sustainable steady state is a hopeless endeavour, however historic societies experiencing regional ecological collapse have indeed often learnt to sustain ecological for a much longer time than urban civilizations, Australia before European Discovery being one example, quite profound ecological management of the land.

  5. Immigration and consequent population increase is a hot topic in the UK because we have a General Election coming up on 4 July and it is debated almost daily. We have a continual flow into the UK of legal and illegal immigrants, refugees and economic migrants, amounting to net immigration of 685,000 last year (immigrants minus emigrants). I believe you have a similar situation in the US. We already import 46% of our ready-to-eat food, and also import large quantities of fertilisers, fossil fuels, pesticides and herbicides which allow us to grow the remaining 54%. It is questionable whether we can continue to sustain this level of immigration, or even continue to feed the population we already have if the flow of imports falters.

    However, politicians don't like "doing the math" and prefer vague promises and soundbites. So there is no mention in the party manifestos of any figures for optimum or maximum level of immigration, size of overall population or food imports, just vague promises to "bring migration numbers down to sustainable levels" or similar. I've examined some of the election issues in greater detail in a recent blog post.

    • Since you're in the UK, you might find Chris Smaje's writings on the subject of food self-sufficiency interesting:

      In my opinion he's a very thoughtful writer who has a clear view of planetary limtis, just like Mr. Murphy, but he's also done a lot of useful work to show that the simplistic "fossil fuels = more food" and industrial farming narratives are too easy. Or as he puts it, the fact that the UK has to import half its food is more of a political choice than an agricultural or technical issue. In any case, I highly recommend his writings to the readership here as a useful supplement to our host's blog.

  6. "Bad News for Team Cancer" – Haha! You had me laughing this morning!

    Tom I love your work! I could praise you for all your great analysis, but today thanks for the chuckle.

    It's intriguing how your population estimates align closely with peak fossil fuel production growth. I'm not sure which will cause the greatest impact, but both seem to lead to a similar future pathway for civilization. There is no doubt some relationship between the two. I tend to think that declining net energy is driving TFR and ultimately dictating the population curve.

    • Since electricity is a small fraction of total power demand, and many activities are not given to electrification, I have a hard time seeing nuclear relieving fossil fuel decline. It's like your shoes are wearing out and someone offers you snowshoes as a substitute. Thanks?

  7. Interesting. With the peak of modernity near and the end of this iteration of modernity inevitable, I have to wonder about climate change. Specifically, how much warmer will Earth become after the end of modernity?

    This question is complicated by permafrost, which contains about 1500 gigatons of carbon (, twice the amount in the atmosphere today. On a warming planet, it will melt. If the long dead plant matter rots, CO2 and methane will be released, causing further warming.

    I'm asking this question because I think Antarctica has enough fossil fuel reserves to kickstart a second attempt at modernity. If the continent becomes warm enough, it will be settled by people using technology, making a second industrial civilization inevitable. Such an attempt would have even more disastrous consequences.

    • The problem is that we climbed the ladder empirically. The reserves in Antarctica aren't enough to do that again – and with what? All the resources we apply energy to, are doing the 'next-worst' trajectory thing too. So they'd be well down the entropy track, pollution too.

      No, a re-boot is not likely. A bumpy triaging descent is more likely; financial collapse and war are the wildcards. (Few cross into what happens to the debt currently held – which makes heroic assumptions about what's left…. (If faith in that underwrite – essentially if folk realise that money is not the 'store of wealth' they assumed it to be , and pull the plug a la 2007/8 – collapses, so does global trading. Ans shortly thereafter, almost everything else). War, of course, can turn nuclear..
      Extraction of fossil energy away down there, will be a rung too high on the ladder, from where they'll have fallen.

      • I think we might be talking about different things. I envision an Antarctic reboot occurring well after this industrial civilization has completely collapsed, with settlers of the formerly glaciated continent utilizing resources once covered by kilometers of ice.

        Antarctica has large, though poorly constrained, amounts of coal in the transantarctic mountains ( along with scattered deposits across the rest of the continent. Furthermore, Russia reportedly found 511 billion barrels of oil off the Antarctic coast. ( I agree that these deposits are highly uneconomical today because any mining effort will have to contend with extremely difficult logistics and glacial ice. But on a world ravaged by climate change 1000 years from now, where all the world's ice has melted, Antarctica will be dangerously green.

        • Interesting to see someone bring this up. I've thought for a while this would be a great premise for a deindustrial novel, but I'm not sure how relevant it is to our predicament in the real world. First, how sure can we be about potential fossil fuel reserves in Antarctica?

          And even if we assume they exist, like you say yourself, we're talking centuries or millennia before anyone could build a civilization down there. In a thousand years, won't most of the worst effects of our current climate spike have abated anyway? If nothing else, industrial civilization will be long gone and people will have adapted to the new world. So if someone were to try for a new industrial revolution in Antaractica, they'd be starting from more or less a blank slate, not adding to our current problems. Or: I'd think the biosphere can recover quite a bit in a millennium or two. Plus, even granting all this, I doubt that one continent has enough fuels for a second globe-spanning industrial civilization.

          (Also note the very value-laden language: "ravaged"? There's nothing intrinsically "better" about the 1960-1990 temperature normal, it's just what the current biosphere is adapted to and the basis for our civilization. Moving away from it will certainly ravage the latter, but the planet itself has been much hotter and cooler and will be fine with time. And of course, in a thousand years +4.5C or whatever will be the normal for anyone living then, not an aberration)

          Finally, it's not at all sure anyone alive by then would know fossil fuels exist, or think to exploit them. See the old chestnut about Rome never having an industrial revolution etc. Personally I tend to think industrialism and the whole infinite expansion thing might be a quirk of Western/European/Faustian/whatever you prefer to call it-culture that won't necessarily happen in another time and place even if the resources are theoretically there.

        • Yes, the climate is changing. 1000 years from now, the only thing that seems certain is that modernity will have ended (at last). Without extra CO2 from IC, the climate may begin to cool and stablize… who knows? Ok, there appears to be a correlation between CO2 emissions and warming, but modelling such a large, complex system as long-term global climate might be beyond humans.

  8. As always, projecting current trends onto future data is fraught with problems. I don't see how one can predict fecundity in the face of phase reversals of most curves that we have only seen going up and to the right.

    I note that the World3 model shows an increase in birth rates after the collapse of both industrial output and food production, which may come as a surprise.

    But this is something I expected once we pass peak power or peak energy or peak oil or whatever one wants to call it.

    It's probably safe to assume that such governments that survive won't be able to afford "programs" any longer, such as universal health care and universal pension. And also that we'll all be intimately involved with our food supply.

    Currently, children are an economic liability, kept going as a sort-of hobby. But under the coming conditions, children may once again become an economic asset.

    I see women returning to breeding their slave labour force and retirement plan, probably in the next decade or two. And thus, population pressure will still be there even as carrying capacity, technology, and affluence all go down.

    I've been doing some family genealogy work lately. It wasn't that long ago that families of 7+ children were common, and that infant mortality took about one out of five.

    A reversion to the mean is inevitable, once this one-time energy blip passes!

    • I agree that the downside of the curve changes the scene entirely so-as to make any projections meaningless, and I have said so several times (calling it garbage by 2100, for instance). But the peak and turnover might be more confidently predicted based on trends that are less likely to suddenly change in the next ten years.

      The LtG models showed both birth and death rates increase as population declined (death rates increasing faster than birth rates), which certianly feels plausible to me. But do bear in mind that the conditions relevant to your genealogy project were not "the mean" at all, but in the context of an earlier stage of modernity. Reversion to 20,000 BC seems more plausible to me than reversion to 1700, although it might well traverse 1700-style practices along the way.

  9. Tom, I just watched your newest video. Excellent. Are you aware of this 2023 'recalibration' of the LtG World3 model? In the video you reference the 2005 update. I'm not sure, but this one seems more recent. I think it seems to support the conclusions you are making.

    • Yes, I was pointed to this a little while back. It also came up in the comments on my (re-posted) at Resilience, and I responded thusly (copied here verbatim):

      I had seen this. A few unsettling mysteries: the recalibration shows industrial output falling sharply after 2020, down about 20% by now (already falsified); persistent pollution is much delayed, and does not correlate to the rate of resource use (which they modeled just as fossil fuels, so I'd expect pollution to go like the rate of FF use). In their comparisons to empirical data (Figs 4 and 5), their recalibration is farther from data than either BAU or BAU2 (e.g., population peaking at 7.5 billion–falsified), leaving me scratching my head and wondering if they use the word "recalibration" the same way I do.

  10. Looking at the various peaks discussed here there are two others I think are interesting.
    1) Peak knowledge. When does the current industrial civilization (ic) reach peak knowledge. So much of our knowledge comes from the development of better instruments to probe reality. At some point soon the current ic cannot afford to develop or even maintain cutting edge infrastructure like the JWST and Hubble telescope.
    2) Peak capability. Related to 1 but different. This could be something like the maximum space lift capacity or maximum computer power.

  11. I'm really curious what you think about the developments in AI and where this will go given peak power.
    (I'm just personally curious because so many around me are projecting into the future about AI and what it will/can do.)
    I read the WaPo article yesterday about the massive electricity demands for AI, and in particular, what that is doing to demands in my state of Washington. My own utility is pushing hard for developing "renewables" here in my county because they are so worried about rolling blackouts due to increased demand (not just from AI, but from population growth and all that goes with it, plus the steady removal of coal fired power plants from the grid).
    Anyway, given the massive amounts of electricity required by AI and other industries that aren't always on the grid (i.e. they can have separate power stations to supply just the data centers, for instance, but often pull from the grid as backup), I'm curious how that fits in with projections for the future. Thanks.

    • I know this isn't the thrust of your question, but I'll first point out that—although possibly wrong—I'm not too bothered about AI. My experience with it is that it's pretty mediocre, which is enough to cause trouble, but not enough to dominate our world. Large-language models are a really great parlor trick that may be nearly topped out and is a dead-end in terms of a more general intelligence (see and

      That said, AI will be employed by mediocre folks around the world (a step up for them) to drive the modernity machine even harder. So it seems like a net harm, for sure (and as you point out a huge energy hog). As to that, it might be by coincidence that the scale of AI-driven energy demand is close to renewable output, so that it sucks all that "green" energy to make the world worse (like today, but more so). At this point, I'm beginning to think that the demographic trends pull the plug on capitalist economies, and AI will be one of many casualties because it depends on a provision that will be increasingly hard to supply.

      • Thank you. I agree with you. The numbers for supplying AI with energy are just eye-popping, but of course it remains to be seen whether that materializes. When there's a LONG waiting list for "renewable" energy projects to get on the grid, I can see more companies building out their own energy supplies, which is what the WaPo article described, adding (unfortunately) to the overall destruction caused by the constant demand for more energy. And building all those chips & CPUs, along with the computers, data centers, cooling systems, etc. add to the burden, too. So ultimately, it seems that AI will just speed up (how much? yet to see) the path to collapse.

Comments are closed.