Monday, November 19, 2018

Peak Oil, 20 Years Later: Failed Prediction or Useful Insight?

Peak Oil by Campbell and Laherrere 1998

20 years ago, Colin Campbell and Jean Laherrere published an article on "Scientific American" that was to start the second cycle of interest on oil depletion (the first had been started by Hubbert in the 1950s). Their prediction turned out to be too pessimistic, at least in terms of the supply of combustible liquids, still growing today. Yet, it was a valuable warning of things to come, unfortunately ignored by decision-makers worldwide. 

The first cycle of interest in oil depletion was started by Marion King Hubbert in the 1950s. Although it provided successful predictions for the production of crude oil in the US, the interest in oil depletion waned in the 1980s. The same destiny of growth and decline awaited the second cycle, that went under the name of "peak oil movement" and that was generated in 1998 by a famous article published by Colin Campbell and Jean Laherrere on "Scientific American." 

Today, the second cycle is winding down and even mentioning the concept of "peak oil" is enough to be branded as a diehard catastrophist, unable to understand how the fracking revolution is leading us to a new age of prosperity under America's energy dominance. Yet, there are symptoms that the great peak could be finally arriving and - who knows? - a third cycle of interest in oil depletion could be starting. 

I published some considerations on this subject in an article that appeared on "Energy Research & Social Science" -- it is "open access" and you can find it at this link. After re-examining the story of the peak oil cycle, I conclude that there was no solid reason to reject the peak oil studies, as it was done starting in the mid 2000s. The reasons for the rejection were related more to the incompatibility of the peak oil concept with the (still) current economic views based on the idea that the depletion of natural resources is not -- and cannot be -- a constraint to economic growth. 

It will take time before some concepts percolate from biophysical economics into mainstream economics - if they ever will. In the meantime, humans continue to destroy the resources that make them live, running as fast as they can toward the Great Cliff. 

Here is an excerpt from my paper -- the conclusions

by Ugo Bardi
Energy Research & Social Science
Volume 48, February 2019, Pages 257-261

... Overall, we can say that, even though the role of non-conventional oil sources was not correctly evaluated and the date of the peak missed at the global level, the Hubbert theory produced correct predictions and, in general, a valuable warning of difficulties to come. So, there never were compelling reasons based on historical data to dismiss the peak oil idea as wrong or untenable. Nevertheless, this is what happened.


Peak Oil, Climate Change, and Limits to Growth – are related to each other and have in common the fact that the models on which they are based predict the unavoidable decline of the world’s economy or, at least, the impossibility for it to keep growing for a long time. This view easily leads to a “doomerish” vision of the future and the peak oil movement tended to regard peak oil as an apocalyptic watershed for humankind, an interpretation surely not based on anything that the model in itself could support. Perhaps in agreement with this millenaristic attitude, the peak oil movement mostly failed to generate a political proposal. This point is well described by Schneider-Matherson [10] who shows how the members of the movement tended to prepare for the event in individual terms, emphasizing local and personal resilience. In some cases, they adopted or proposed a survivalist strategy, including stocking food, guns, and ammunition in expectation of the imminent collapse. Needless to say, this attitude didn’t endear the movement to the mainstream decision makers.

We may therefore conclude that the peak oil predictions were considered incompatible with the commonly held views that see economic growth as always necessary and desirable and depletion/pollution as marginal phenomena that can be overcome by means of technological progress. That was the reason why the peak oil idea was abandoned, a victim of a “clash of absolutes” with the mainstream view of the economic system. In the clash, peak oil turned out to be the loser, not because it was “wrong” but mainly because it was a minority opinion. The future will bring new data and, with them, the concept of peak oil might regain popularity for a second time, just as it did for the first time with the 1998 work of Campbell and Lahérrere.

Sunday, November 11, 2018

Should we Prepare for a New World War? Answers from the Patterns of Past

 I know that I have crammed together too many ideas here: Tolstoy, St. Francis, critical phenomena, thermodynamics, and more,  - it is contrary to the rules of blog posts. But the centennial of the end of the Great War gave me the occasion to write something about how, in 1914, the European states sleepwalked into the Great War just like we may be doing nowadays. If the Great War couldn't end all wars as it was said to be able to do, the greater one that may be coming could actually do that, but in a very different way. The new war could lead to the extinction of humankind. So, what hope do we have? I don't know, but the first step to solving a problem is to understand it. So far, humans haven't learned anything much from the mistakes of the past but, who knows? Maybe one day they will.

The centennial of the end of the Great War is a good occasion to rethink a little about wars: why, how, and when wars occur and if there is any hope to stop blindly walking along a path taking us to the possibility of the complete annihilation of humankind. It is a question that has been posed many times and never satisfactorily answered. Perhaps the first to try to answer it was Leon Tolstoy in his “War and Peace” novel, (1867), where he wondered how it could be possible that a single man named Napoleon could cause millions of men to move all together eastward with the purpose of killing other men whom they had never met and they had no reason to hate.

Tolstoy was not a scientist, he operated on the basis of experience and intuition. But, just like Darwin understood the laws of genetics by experience and intuition, Tolstoy understood the laws of social networks. In War and Peace, he wrote:

The combination of causes of phenomena is beyond the grasp of the human intellect. But the impulse to seek causes is innate in the soul of man. And the human intellect, with no inkling of the immense variety and complexity of circumstances conditioning a phenomenon, any one of which may be separately conceived of as the cause of it, snatches at the first and most easily understood approximation, and says here is the cause.”

“And so there was no single cause for war, but it happened simply because it had to happen”

Tolstoy had grasped the concept that war is not the result of mad dictators giving orders to their followers. It is not even a rational struggle for resources or for money, although that factor plays a role. It is just something that happens beyond the human capability of controlling it, or even of understanding it.

One century after Tolstoy, statistics had advanced to the point that a quantitative analysis of the war phenomenon became possible. The British meteorologist and physicists Lewis Fry Richardson (1881-1953) applied the concept to the frequency and the size of human wars and more in general to what he called “deadly quarrels.” Richardson found that wars are random phenomena, unpredictable and unrelated to almost anything else: they just happen.

More recent work confirmed the early analysis by Richardson, finding that wars follow "power laws." Some recent work we did with my coworkers Martelloni and Di Patti confirms this result over a time scale of some 600 years and worldwide (preliminary results, to be published soon). It is a subject that I already discussed in an earlier post.

Power laws are typical "emergent phenomena" that take place in complex systems. They are the result of the dissipation of accumulated energy that occurs not gradually but in bumps. The quintessential system that behaves in this way is the "sandpile" that Per Bak used as a representation of the condition that he called "self-organized criticality." Fascinating in a mathematical model, these bumps can be deadly in the real world. Earthquakes, landslides, avalanches and more phenomena involving natural disasters tend to occur following power laws.

These results confirm Tolstoy's intuition: wars are not the result of ideologies, religions, mad rulers, or the like. They emerge out of a social network as a result of the way the system is connected. That doesn't mean there are no causes for wars: they are the result of accumulated capital that needs to be dissipated in some way. Wherever there is an unbalance in the accumulation of capital, the excess will spill from the more endowed side to the less endowed one. In a sense, war is the offspring of capitalism, but capitalism is just another emergent phenomenon of complex societies. In short, wars are not caused by a lack of resources, they are caused by an excess of resources.

When a new world war will start can't be exactly predicted -- it is like for earthquakes. Nobody can say exactly where and when a major earthquake will take place, but we know that there is a certain probability for it to occur in seismic zones and, sooner or later, it will. The same seems to be valid for wars. So, the fact that the start of wars can't be exactly predicted doesn't mean we can't see that today we are running at full speed toward a new one. If the trend of the past 600 years continues to hold, there is a larger than zero probability that we'll see a new conflagration that could surpass of an order of magnitude -- or perhaps more than that -- the second world war in terms of destruction and number of victims.

Could we do something to avoid that outcome? We have to look at the basics: if wars are like earthquakes, they are a thermodynamic phenomenon that dissipates accumulated energy. In the case of earthquakes, there is nothing we can do to avoid the movement the Earth's tectonic plates and the accumulation of energy at the faults that separate them. In the case of wars, the accumulated energy to be dissipated is in the form of capital, in a general sense of money, riches, population, resources, etc. Can we avoid the accumulation of capital? Not so easy in a society that sees the accumulation of riches as a good thing to be encouraged in individuals as well as in entire societies.

So, is it our destiny to see the end of humankind in a series of clouds of radioactive smoke? Perhaps. But I would also like to add something more: the cycle of energy dissipation in the form of war is something that we can approximately measure only for a period of existence of humankind of a few centuries in the past. And this was a period of economic expansion, eventually propped up by the availability of fossil fuels. Once we cross over the peak of this great historical cycle, many things could change and capital might be more difficult to accumulate. That would change many things, perhaps also the probabilities of major wars to occur.

Of course, you don't need a lot of capital accumulating in order to have a war -- we know that tribal societies are far from being peaceful. But tribal wars, at least, don't take with them the whole Earth's ecosystem. It is, after all, something that St. Francis had already discovered long ago at the individual level: material poverty can make you a better person if you willingly accept it. It took a thousand years before someone (Aurelio Peccei among the first) that inequality among nations is the mother of all wars. Could the human society embrace "Lady Poverty" as Francis did? Would that avoid wars or, at least, the kind of apocalyptical wars that could be waged today? We cannot say, but perhaps a dim glimmer of hope remains even in this dark period.

Thursday, November 8, 2018

Will we Ever be Able to End Wars? How the Wise are Confused

One hundred years after the end of the war that was to end all wars, the First World War, we still don't understand what wars are, why we fight wars, why we can't stop fighting them. We are surrounded, it seems, by things we don't understand: why do people fight wars? Why are wars so commmon? Why can't we find a way to stop them? Why people still fall for the most obvious propaganda tricks?

Below, you can find an excerpt from the 1980 book by David Wilkinson, "Deadly Quarrels" that starts with a list of the various theories put forward in modern times to explain how peace could be attained. Still perfectly valid today, the list highlights the confusion pervading the attempts to put an end to war. It reminds the 200+ theories that Demandt reports for the reasons of the fall of the Roman Empire. More than that, it reminds of Paul of Tarsus (Corinthians 1) when he says "God hath chosen the foolish things of the world to confound the wise." And this is war, a foolish thing that keep confounding us.

From "Deadly Quarrels" by David Wilkinson, 1980 (*)

The most common way of contributing to the debate over war causation and peace strategy has been to assert some definite theory, to show how it fits current circumstances, and to deduce immediate practical conclusions. If we follow this public debate, we may expect to be told that war is a consequence, for instance, of wickedness, lawlessness, alienation, aggressive regimes, imperialism, poverty, militarism, anarchy, or weakness. Seldom will any evidence be offered. Instead the writer is likely to present a peace strategy that matches his theory of war causation. We shall therefore learn that we can have:

  • Peace through morality. Peace (local and global) can be brought about by a moral appeal, through world public opinion, to leaders and peoples not to condone or practice violence, aggression, or war, but to shun and to denounce them.
  • Peace through law. Peace can be made by signing international treaties and creating international laws that will regulate conduct and by resorting to international courts to solve disputes.
  • Peace through negotiation. Peace can be maintained by frank discussion of differences, by open diplomacy, by international conferences and assemblies that will air grievances and, through candor and goodwill, arrive at a harmonious consensus.
  • Peace through political reform. Peace can be established by setting up regimes of a nonaggressive type throughout the world: republics rather than monarchies; democratic rather than oligarchic republics; constitutionally limited rather than arbitrary, autocratic regimes.
  • Peace through national liberation. Peace can be instituted only through the worldwide triumph of nationalism. Multinational empires must be dissolved into nation-states; every nation must have its own sovereign, independent government and all its own national territory, but no more.
  • Peace through prosperity. Peace requires the worldwide triumph of an economic order that will produce universal prosperity and thereby remove the incentive to fight. Some consider this order to be one of universal capitalism, or at least of worldwide free trade; others hold it to be some species of socialism, reformist or revolutionary, elitist or democratic.
  • Peace through disarmament. Peace can be established by reducing and eventually eliminating weapons, bases, and armies, by removing the means to make war.
  • Peace through international organization. Peace can be established by creating a world political organization, perhaps even a constitutional world government resembling national governments, to enforce order and promote progress throughout the world.
  • Peace through power. Peace can be maintained by the peaceable accumulation of forces, perhaps overwhelming, perhaps preponderant or balancing or adequate-sufficient to deter, defeat, or punish aggression.

Much current talk on war and peace amounts to no more than high-handed assertions that my chosen theory is right, and all others therefore are evidently wrong.

(*) Wilkinson's "Deadly Quarrels" is a discussion of the studies performed by Lewis Fry Richardson from the 1930s to his death in 1953. Richardson was one of the first researchers who tried to put forward a quantitative theory of war. With my coworkers Gianluca Martelloni and Francesca Di Patti, we are re-examining the statistical patterns of war. We are finding, unfortunately, that Richardosn was basically right: wars are a random phenomenon similar to earthquakes and avalanches -- very hard both to predict and to stop. 

Monday, November 5, 2018

Epistemology of a Dying Empire: Can Growth Last Forever?

Recently, Michael Liebreich published an article titled "The Secret of Eternal Growth." I have been mulling over in my head if it is appropriate to spend time discussing one more mishmash of legends, including the one that's by now a classic, the "errors" that the Club of Rome is said to have made with the 1972 report, "The Limits to Growth." Eventually, I decided that it was worth a post, not so much because the post by Liebreich is especially wrongheaded or silly, but because it illustrates one basic point of our civilization: who, and how, takes decisions? On which basis?

In the end, I think we have a problem of epistemology, the question of the nature of knowledge. In order to make decisions, you have to know what you are doing -- at least in principle. In other words, you need some kind of "model" of reality in order to be able to act on it. It was Jay Forrester, the father of system dynamics and the originator of the "Limits to Growth" report who pointed out that, (World Dynamics, 1971, p. 14)

Everyone uses models all the time. Every person in his private life and in his community life uses models for decision making. The mental image of the world around one, carried in each individual’s head, is a model. One does not have a family, a business, a city, a government, or a country in his head. He has only selected concepts and relationships that he uses to represent the real system.

And the big question is where these "selected concepts" come from. My impression is that the mind of our leaders is a jumble of ideas and concepts grafted from haphazard messages that come from the media. Our leaders use no quantitative model to take their decision, only whim and feelings. This is how an idea such as MAGA came about.

The point is that there seems to exist a certain convergence of ideas and concepts in the mediasphere. Somehow, a consensus tends to appear and it is reinforced by repetition. This is how the world's leadership tends to assume the existence of some self-evident truths, such as that economic growth is always good.

The article by Liebrich is a good example of this process. We have an article written by someone who is influential: he is senior contributor at Bloomberg, and also an engineer. What is most disheartening about it is how it is based on half-baked ideas, superficial interpretations, half-truths, and legends. Just as an example, we read in the article that:

. . . a group of concerned environmentalists calling themselves the Club of Rome invited one of the doyens of the new field of computer modelling, Jay Forrester, to create a simulation of the world economy and its interaction with the environment. In 1972 his marvellous black box produced another best-seller, Limits to Growth (iv), which purported to prove that almost every combination of economic parameters ended up not just with growth slowing, but with an overshoot and collapse. This finding, so congenial to the model’s commissioners, stemmed entirely from errors in its structure, as pointed out by a then fresh-faced young economics professor at Yale, William Nordhaus.

Note how Liebrich provides a reference to the "Limits to Growth" book, but none for the supposed "pointing out of the errors in its structure" by the "fresh-faced" William Nordhaus. The reality is that Nordhaus wrote a paper criticizing Forrester in 1973 and Forrester responded to it with another paper, defending his approach. It is perfectly legitimate to think that Nordhaus was right and Forrester wrong, but you can't say that that the purported "errors" in the model are an established fact. I discussed this story in my book, "The Limits to Growth Revisited" and in a recent post on "Cassandra's legacy." Basically, Liebrich reported a legend without bothering too much about verifying it.

There is much more in Liebrich paper that can be criticized in terms of mistakes, personal attacks, misinterpretations, and more (see also another critical assessment by Tim Jackson). But the point is how ideas are thrown into the mediasphere and there they float, to be picked up by human minds as flu viruses flow in the air. Here, Liebreich's thesis is likely to have a certain influence because it is so cleverly presented: basically it tells us that you can eat the pie and still have it. It tells people that humankind can keep growing while reducing its impact on the ecosystem. It is like telling a heroin addict that heroine is good for health and it is OK to continue using it because technological progress will make it possible to get the same kick - or even more kick - from a lower dose. That is what a heroin addict likes to hear, but it won't work in the real world.

The same is true for our leaders and for all of us. We tend to make choices on the basis of what we like, not on how things stand. The sickness of the Empire, in the end, is just bad epistemology.

(h/t Anders Wijkman and Nora Bateson)

Sunday, November 4, 2018

One Hundred Years Ago: the end of the war that should have ended all wars.

The front cover of the book I published this year dedicated to the memory of a forgotten hero of the Great War, Armando Vacca. He fought for peace as much as he could, to the point that he had to give his life for a cause he had fought against. He died as a martyr for his Christian faith on the Carso mountains on July 21st, 1915.

One Hundred years ago, on Nov 4th, 1918, the Great War, also known as the First World War, ended for Italy with Austria-Hungary surrendering. The war would last a few more days on the Western front. I think it is appropriate to celebrate this day with some words of a beautiful song by Eric Bogle, "The Green Fields of France."

Ah, young Willie McBride, I can't help wonder why
Do those that lie here know why did they die
And did they believe when they answered the call
Did they really believe that this war would end war?

For the sorrow, the suffering, the glory, the pain
The killing, and the dying was all done in vain...
For, young Willie McBride, it all happened again
And again, and again, and again, and again

Eric Bogle –The Green Fields of France

Sunday, October 28, 2018

The Seneca Rebound: why Growth is Faster after Collapse. Explaining the European World Dominance

Lisbon: the monument to the European sailors of the age of explorations, starting with the 15th century. What made Europeans so successful in the task of conquering the world? My interpretation is that it was the result of periodic "Seneca Collapses" of the European population which made it possible to accumulate resources that would then be available to propel the European expansion. It is an effect that may be called the "Seneca Rebound" that makes growth faster after a collapse.

The Middle Ages are sometimes referred to as the "Dark Ages" -- this is mostly untrue, but it is not wrong to apply this term to the early Middle Ages, called also the "Late Antiquity"(1). According to some estimates, in 650 AD the European population had shrunk to a historical minimum of some 18 million people, about half of what it had been during the high times of the Roman Empire. If you think that today the European population is estimated to be as more than 700 million people, it is almost impossible for us to imagine the Europe of the early Middle Ages: it was a minor appendage of the Eurasian continent, a poverty-stricken place, nearly empty of people, where nothing happened except for the squabbles of local warlords fighting each other.

Yet, a few centuries later, the descendants of the inhabitants of this backward peninsula of Eurasia embarked in the attempt of conquering the world and were successful at that. By the 19th century, practically all the world was under the direct or indirect control of European countries or of their American offspring, the United States. How could it happen?

The conventional explanation for the European ruling of the world has to do with factors related to the "white man's burden", a term invented by Rudyard Kipling in 1899. According to this interpretation, the European domination was a sort of manifest destiny generated by the superior qualities -- genetic or cultural -- of the European people in terms of being smarter, more laborious, better organized, driven by their Christian faith, and the like. In comparison, the populations of the rest of world were lazy, disorganized, uncultured, and in the grip of superstitions.

Maybe, but the idea that the Europeans conquered the world because they are smarter than the others is not supported by any data. Europeans may find it flattering, but it is an ad hoc interpretation that doesn't help us understand much of what led to the European world dominance. I have been scratching my head on this question for quite a while, until I stumbled into the graph below, showing two drastic "Seneca Collapses" of the European population. The term "Seneca Collapse" indicates a situation where the decline of a complex system is faster than its growth.

Graph from William E Langer, "The Black Death" Scientific American, February 1964, p. 117 -- note how growth is faster after the collapse than it was before. This is what I call the Seneca Rebound.

Note first of all that the data are uncertain and not all authors see the population drop in the European population to have been as drastic as Langer does. But there is a general agreement that a drastic collapse of the European population took place starting in mid 14th century AD. The collapse is often attributed to the spread of the "black death," a continent-wide epidemics of plague. In reality, there were several factors that led the European population to crash down so badly, including famines and a widespread economic crisis. In a complex system it always is difficult to establish a clear-cut chain of causes and effects: when the system crashes, many factors collapse together. The population crash plague that hit Europe in mid 17th century was less drastic, but also associated with a new outburst of the plague. These two Seneca Collapses followed the one I already mentioned, when the Roman Empire collapsed during the 6th-10th centuries AD.

There is a common element of these three collapse: the remarkably rapid recovery that followed. Let's describe that in more detail.

The first collapse (from the 5th to the 8th century). After the fall of the Western Roman Empire, Europe started recovering and soon it was able to mount military attacks against neighboring regions. The first crusade started in 1095 and for some three centuries successive waves of European armies attacked the region we call today the Middle East, succeeding in creating a number of European kingdoms in the area. The result was, ultimately, a failure and the European crusades and the European Middle Eastern kingdoms withered with the mid-14th century.

The Second collapse (mid-14th century). The population crash was brutal, but as soon as Europe started recovering, a new phase of expansion started: it was the age of exploration that we may consider to have started with the discovery of the island of Madeira in 1430 and then proceeding with a remarkable burst of explorations that lasted for about a century from mid 15th century to mid 6th. This burst included Columbus' travel of 1492 and the start of the gradual expansion of Europeans in Africa and in the Americas.

The Third Collapse (mid-17th century). In this case, the collapse was not so drastic as the first two and it didn't really stop Europeans from expanding. But, with the restart of population growth, Europe saw a new phase of economic growth which ushered the age of coal and, with it, the "age of divergence" when Europe truly conquered the rest of the world and started thinking of themselves as carrying the "white man's burden."

So, there is clearly a pattern here: the expansion of the European social system didn't go on smoothly, but in bursts. Over some two millennia, the European population grew from a few tens of millions up to the current 700 million people. In the process, it underwent at least three major crashes but, every time, it restarted growing. This bumpy expansion trajectory is typical of complex systems which tend to show what I call the "Seneca Effect," cycles of slow growth and fast collapse.

Europe, intended as a social system, is a complex system and it does tend to show the Seneca behavior. It is the result of the combination of resource depletion and pollution. Before the fossil fuel age, society had two main natural resources to exploit: fertile soil and forests. Both tend to be overexploited, that is destroyed faster than they can regrow. Forests are cut faster than trees can regrow and the fertile soil is eroded and washed to the sea faster than it can reform. The decline of agriculture not only puts an end to population growth, it causes it to collapse ruinously as an effect of famines and epidemics. The loss of the revenues from forests typically weakens the state and the result is internecine wars which, of course, hasten the collapse. Both wars and epidemics can be seen as forms of pollution and the final result is what I call the Seneca Effect: a decline which is much faster than growth.

But there is life after the Seneca Collapse. The disappearance of a large fraction of the population frees some previously cultivated land for forests to regrow. Then, when the population starts re-growing, people find the new forests as a near-pristine source of wood and -- once cut -- of fertile soil, and the cycle restarts. The new cycle may grow faster than the earlier one because society still remembers the social structures and the technologies of the previous cycle. This is the "Seneca Rebound" -- growth may be faster after collapse. You can see the Seneca Rebound in the curves made by Langer for Europe. Note how growth is faster after the collapses than it was before. This is because, I think, the Europeans had kept the social and technological structures they had developed before the crash -- there was no need, for instance, to re-develop their ship-making technology (3). So, they could exploit more effectively the resources that the collapse had freed.

Then, Forests are the basic resource needed to conquer the world and the Europeans exploited them effectively. Trees provide the wood for ships and the charcoal made from wood provides the material needed to make steel for weapons. Not for nothing, it was said that England had conquered an empire with ships of wood and men of iron.

But how was it that the Europeans were so much better than others at exploiting their forests? As always, success is a question of timing, opportunities, and luck. On the opposite side of the Mediterranean, the Arab civilization was socially and technologically as sophisticated as the European one - perhaps more - but their climate didn't allow forests to grow fast enough to avoid rapid overexploitation (2). The American civilizations we call "pre-Columbian" had forests, but they hadn't yet developed the technologies of steel and of oceanic ships -- they also lacked horses for transportation and as a military weapon. The Chinese, instead, had the technologies and also the forests and, indeed, they embarked in a parallel phase of explorations.

During the 12th-13th centuries an outbreak of the same plague that had affected Europe caused a decline in the Chinese population, that was followed - possibly as a consequence - by the Mongol invasion which led to the fall of the Song dynasty. When the Chinese economy experienced its own Seneca Rebound, the age treasure voyages started in the early 1400s, during the Ming dynasty, in a period when the population had restarted growing. (4)

China population trends according to a reconstruction published by Columbia University.

But the Chinese stopped their exploration phase and retreated within their borders. So, the Europeans found no competition in their worldwide expansion and that was the origin of the history we know.

These considerations are qualitative, but I think there is something in the idea of the "Seneca Rebound" as an engine that propels civilizations forward in bursts. If this is the case, if the world's civilization goes through a new Seneca Collapse, as it is likely to happen, will it restart expanding afterward?  If we manage to avoid that the coming crash is so bad that we lose the knowledge we accumulated over several centuries and that climate change doesn't erase humankind as a species, we may well restart expanding using renewable energy -- this time into space. Why not?


(1) If you are interested in the late antiquity period, and you can read Italian, you should read "L'Impero Globale" a recent book by Alessia Roberta Scopece who finds many parallels that age and our modern Globalization.

(2) The destruction of the Middle Eastern and North African forests may have been irreversible, as I note in this post of mine. (h/t Steve Kurtz)
(3) Nor there was any need to reinvent luxury and, with the rebound, Middle Ages ladies started dressing like high fashion models, as I describe in this post.

(4) Another reconstruction of the Chinese population is shown below, from an article dealing with the same question as this one -- they arrive to completely different conclusions, but it is normal. 

Thursday, October 25, 2018

Why is Overpopulation Ignored by the Media? The Reasons of a Historical Failure

Some people think there exists a conspiracy that prevents the media from ever mentioning the charged word, "overpopulation." Conspiracies do exist but, in this case, my impression is that population is such a charged issue simply because it has to do with the fact that we are all humans and discussing about reducing population touches some inner mechanisms of our psyche that we feel uncomfortable about.

But there is more to that: the real problem with overpopulation is that most decision makers lack the concept of "overshoot,"  a view that didn't exist in the study of social systems until Jay Forrester introduced it in the 1960s.If you don't understand overshoot, at best you can understand that there are limits to population, but you can't understand that population could exceed the limits and crash down ruinously with the deterioration of the agricultural system that feeds it.

The lack of a the concept of overshoot may well be what leads the concerned and the unconcerned to minimize the problem. Many people seem to think that the "demographic transition," the reduction in fertility observed in most rich nations of the world, will spread over all humankind and stabilize the world's population at a sustainable level without any need for governments to intervene to force lower birth rates.

Almost certainly, it is too late for that: we should have started decades ago. But only China implemented a serious policy birth control -- for the rest of the world it was a historical failure.

In the discussion, below, Bernard Gilland discusses the problems we will face in the attempt of stabilizing the human population mainly in terms of the degradation of the agricultural system in its dependence on non-sustainable resources. It is not the only problem, with climate change potentially able to do even more damage to agriculture. At the same time, the many young people in poor countries will push population onto a still growing trajectory. If these two tendencies, population growth and agricultural decline, crash against each other, the result might well be a Seneca Cliff for the world's human population.

A sustainable global population -and why we cannot achieve it

Guest Post by Bernard Gilland

In the period 1975 – 2018, world population increased at an average of 83 million per year, and reached 7.6 billion in 2018. The increase in 2017 was the difference between approximately 145 million births and 62 million deaths. Despite population growth, the global average daily food supply per person rose from 2440 kilocalories in 1975 to 2940 kilocalories in 2015 (1). However, over 800 million people are undernourished and 300 million adults are obese.

Cereals are the most important crops for food and feed; globally, 45 percent of the cereal production is consumed by humans, and 35 percent by livestock. The remainder is used for industrial purposes, including ethanol, beer, whisky and vodka. The rise in world cereal production since the 1960s is mainly due to two technological advances. The first was Haber-Bosch ammonia synthesis, in which atmospheric nitrogen is fixed as ammonia (containing 82 percent nitrogen) which plants utilize for protein formation. Production of Haber-Bosch ammonia began in 1913, but did not begin to rise rapidly until the 1960s. The second advance was the Green Revolution that began in the mid-1960s, after agronomist Norman Borlaug had bred varieties of dwarf wheat that give higher yields in response to heavier applications of nitrogen, phosphorus and potassium fertilizer, pesticides and irrigation. The breeding and use of semi-dwarf rice and hybrid maize paralleled that of wheat.

The most striking achievement of chemical agriculture is the maize yield in the U.S., which rose from 2.5 tonnes per hectare (40 bushels per acre) in 1950 to 11.0 tonnes per hectare (175 bushels per acre) in 2016. The global cereal yield rose from 2.81 tonnes per hectare in 1992-96 to 3.91 tonnes in 2012-16 (2). Linear extrapolation of the 1992 - 2016 yield trend (52.3 kg per hectare per year) gives a yield of 5.73 tonnes per hectare in 2050. If the population in 2050 is taken as 9.85 billion (3), and the harvested cereal area remains 718 million hectares (as in 2016), production per person in 2050 would be 420 kg, 10 percent above the 2016 level of 382 kg; the uncertainty is about 10 percent either way. Assuming that the global average cereal yield without using nitrogen fertilizer is 1.6 tonnes per hectare, and that fertilizer increases grain yield by 30 kg per kg nitrogen applied, the global average nitrogen application on cereal crops, 80 kg per hectare in 2015, would be approximately 140 kg per hectare. If the incremental yield-nitrogen ratio rises to 35 by 2050, the nitrogen application would be 120 kg per hectare.

The success of the Green Revolution created three major ecological problems:

1. Globally, about half the applied nitrogen is taken up by the crop plants; the remainder volatilizes in the form of ammonia and nitrous oxide (a powerful greenhouse gas) or leaches to groundwater, resulting in eutrophication (the formation of algae) in rivers, lakes and coastal waters; this creates “dead zones” in which fish cannot live.

2. Applying nitrogen, phosphorus and potassium fertilizer to crops changes the balance between these nutrients and those needed in small or trace amounts; the latter include calcium, sulphur, magnesium, iron, manganese, copper, zinc, cobalt, boron and selenium.

3. Approximately 40 percent of global irrigation water is obtained by pumping groundwater from tube wells; this has resulted in the depletion of aquifers and the lowering of groundwater levels, thereby contributing 0.4 mm to the global sea level rise of 3.4 mm per year (4).

As population growth increases the need for fertilizer, it follows that population reduction would ultimately solve the ecological problems. Unfortunately, human nature is such that global population reduction is not feasible. The reasons for this are given in the following.

In 1950, France had a population of 42 million and 20 million hectares of arable land, i.e. 2 persons per arable hectare. The nitrogen fertilizer application on cereals was negligible, and cereal production per person was about 400 kg per year, slightly higher than the present world average. If the ratio of population to arable land were 2 persons per hectare on the world’s 1.6 billion arable hectares, world population would be 3.2 billion. Reducing world population to this size would mean reducing the global average fertility rate (currently 2.5 children per woman) to 1.5 by 2050 and holding it at that level until 2200. The proportion of the population in the 65+ age-group would rise to 35 percent. Such a drastic change in the age distribution would mean raising the pensionable age to 70 years or more.

Adopting and enforcing a population limit for each country would be an insurmountable obstacle, as Charles Galton Darwin pointed out in 1952 (5). To lower the global average to 2 inhabitants per arable hectare, countries such as Canada, Russia, Australia and Argentina would not be required to reduce their populations, but would not be permitted to reach 2 inhabitants per arable hectare; they would be obliged to have a grain surplus for export to countries that need grain imports. China and India would each have to reduce its population to roughly 300 million; the combined population of the two countries would then be 20 percent of the world population instead of the present 35 percent (6). The relative population reductions in Japan and Egypt, which have 30 and 33 inhabitants per arable hectare respectively, would be much greater (6).

The population of China is projected to peak at 1.45 billion around 2030 and decline to one billion by 2100. This is partly a result of the so-called one-child policy launched in 1979 (in reality a 1.5-child policy). It was replaced by a two-child limit in 2016, but the fertility rate remains 1.6. Japan has a population of 126 million and a fertility rate of 1.4; the population is projected to decline to 102 million in 2050 and 60 million in 2100. These projected long-term declines are likely to be halted by pro-natalist policies based on the advice of growth-obsessed economists who believe that population decline results in a shortage of labour. A world population peak of at least 10 billion is almost inevitable, and this would make 70 percent of the world’s population dependent on Haber-Bosch ammonia. This is not sustainable, but there is no solution in sight. As a sustainable population cannot be attained by fertility decline alone, a mortality rise is highly probable. We can only guess when.

Bernard Gillan is an independent researcher with a degree in Engineering, based in Copenhagen, Denmark. He is the author of several papers on demography and population


1. FAOSTAT data.

2. World Bank data.

3. Population Reference Bureau. World population data sheet 2018.

4. Konikov, L.F. 2011. Contribution of global groundwater depletion since 1900 to sea-level rise. Geophysical Research Letters, 38; L17401.

5. Darwin, C.G. 1952. The next million years. Hart-Davis, London.

6. Lionos, T.P., A. Pseiridis. 2016. Sustainable welfare and optimum population size. Environment, Development and Sustainability, 18(6), 1679 - 1699. According to the authors, the optimum population of the world is 3.1 billion, and the populations (in millions) of the ten most populous countries are:

China 253, India 341, United States 326, Indonesia 88, Brazil 156, Pakistan 43, Nigeria 79, Bangladesh 17, Russia 249, Japan 9.2. The figure for Egypt is 7.4.


Ugo Bardi is a member of the Club of Rome and the author of "Extracted: how the quest for mineral resources is plundering the Planet" (Chelsea Green 2014). His most recent book is "The Seneca Effect" (Springer 2017)