Monday, July 9, 2018

Ugo Bardi

Climate Change as a Game of Russian Roulette. Ugo Bardi, Cassandra's Legacy. June 13, 2018.
In a science fiction story I read years ago, the protagonists live in the future and have forgotten what guns are. Then, someone finds a still working handgun and starts playing with it. As you may imagine, the results are tragic. 
Now, let's make a small exercise in epistemology. Suppose that you are one of the characters of that sci-fi story. You have never seen a gun before and you would like to understand what it is and what it does. Basically, there are two ways of approaching the question: the scientific/reductionist way and the Bayesian/evolutionary way. Let me explain these concepts. 
The scientific/reductionist way. You dismantle the unknown object and try to build a model of its inner workings. You note the mechanical system that makes a metal hammer hit on the chambers of a spinning drum. One of these chambers contains a brass cylinder partly filled with a mixture of chemicals that you can analyze. You find that the mechanical stress generated by the hammer may ignite the chemicals, producing high-pressure gases which might push an ogival chunk of some 100 g of lead through the front barrel at a speed of the order of 300 m/s. If you align the barrel with a human head, the effects of the chunk of lead passing through the brain would be hard to simulate, but they might involve serious damage. You conclude that it is, most likely, a weapon. 
The Bayesian/evolutionary way. You examine the gun and try to build a probability estimate based on empirical tests. You note a small lever at the bottom and proceed to pull, noting that it generates a clicking sound. You pull it a few more times: nothing happens as long as the hammer doesn't hit the loaded drum chamber (which you don't know about since you didn't dismantle the gun). Then, you conclude that it is probably a musical instrument. 
The difference in this approach shows mostly if you use the gun to play the Russian Roulette (*) with one bullet in a six-chambers drum. Then, after five "clicks" the frequentist would tell you, "pull the trigger one more time and you are dead." But the Bayesian would say (**), "since you tried five times and nothing happened, then you are reasonably safe if you try once more." 
Of course, these two viewpoints are extreme, there are plenty of intermediate ways to approach a problem, but they indicate how difficult it may be to deal with something unknown. And that's the big, big trouble with climate change. It is gigantic, enormous, complicated, and most likely dangerous. But we are like the characters of the science fiction story of the unknown gun: we have no direct past experience to rely upon. 
Without disparaging the Bayesian method, surely helpful in many cases, it may be a suicidal approach to use when dealing with something dangerous for which you have insufficient statistical data. That's the case of the Russian Roulette and also of climate change. 
There follows the question: do people think Bayesian of Frequentist? It is a controversial subject but, personally, I'd say that it makes sense to say that most people think Bayesian. That may be the reason why humankind has such a cavalier attitude toward the danger of climate change. The statistics we have on climate for the recent past don't tell us anything about the possibility of a true catastrophe. So, we might be tempted use a Bayesian approach to conclude that we have no reason to be worried - and the more time goes by without catastrophes occurring, the more this conclusion seems to be reinforced. After all, haven't we pulled the trigger of this thing you call "gun" already five times? It has to be harmless. 
Of course, the scientific/reductionist approach tells us otherwise when the climate system is analyzed and modelized. It tells us that the change may be extremely destructive - actually catastrophic. But that approach seems to be reserved for a small fraction of the population trained in the scientific method. There follows that humankind is playing the Russian roulette with the Earth's climate. And that might well end the way a Russian Roulette game must eventually end.

Five Things You Should Know About Collapse.  Bardi. May 15, 2018.
  1. Collapse is rapid. Already some 2,000 years ago, the Roman philosopher Seneca noted that when things start going bad, they go bad fast. It takes a lot of time to put together a building, a company, a government, a whole society, a piece of machinery. And it takes very little time for the whole structure to unravel at the seams. Think of the collapse of a house of cards, or that of the twin towers after the 9/11 attacks, or even of apparently slow collapses such as that of the Roman Empire. Collapses are fast, it is their characteristic.
  2. Collapse is not a bug, it is a feature of the universe. Collapses occur all the time, in all fields, everywhere. Over your lifetime, you are likely to experience at least a few relatively large collapses: natural phenomena such as hurricanes, earthquakes, or floods - major financial collapses - such as the one that took place in 2008 - and you may also see wars and social violence. And you may well see small-scale personal disasters such as losing your job or divorcing. Nobody at school taught you how to deal with collapse, but to cope with it you'd better learn at least something of the "science of complex systems."
  3. No collapse is ever completely unexpected. The science of complex systems tells us that collapses can never be exactly predicted, but that's not a justification for being caught by surprise. You may not know when an earthquake will strike but, if you live in a seismic zone, you have no justification for not take precautions against one - such as having emergency tools and provisions. The same holds for defending yourself and your family against thieves, robbers, and all sorts of bad people. And make plans for political unrest or financial troubles. You cannot avoid some collapses, but you can surely be prepared for them.
  4. Resisting collapses is usually a bad idea. Collapse is the way the universe uses to get rid of the old to make space for the new. Resisting collapse means to strive to keep something old alive when it could be a better idea to let it rest in peace. And, if you succeed for a while, you are likely to create an even worse collapse - it is typical. The science of complex systems tells us that the main reason for the steep "Seneca Collapse" is the attempt to stave it off. So, let nature follow its course and know that there some problems may be unsolvable but can be surely worsened.
  5. Collapse may not be a problem but an opportunity. Collapse is nothing but a "tipping point" from one condition to another. What looks to you like a disaster may be nothing but a passage to a new condition which could be better than the old. So, if you lose your job, that may give you the opportunity to seek a better one. And if your company goes belly up, you may start another one without making the same mistakes you did with the first. Even disasters such as earthquakes or floods may be an opportunity to understand what's your role in life, as well as give you a chance to help your family and your neighbors. The Stoic philosophers (and Seneca was one) understood this point and told us how to maintain one's balance and happiness even in the midst of difficulties.

Saving the World: Top-down or Bottom-up? Bardi. April 9, 2018.

Come On: Capitalism, Short-termism and the Destruction of the Planet. A new Report from the Club of Rome. By Ernst von Weizsaecker and Anders Wijkman - Book Review by Ugo Bardi.
Nearly half a century has passed since the publication, in 1972, of the first – and still the most famous – report of the Club of Rome, “The Limits to Growth.” That first report was heavily criticized but, nowadays, it is turning out that it had correctly identified the main lines of the trajectory that the human industrial society was to follow and is still following. To the authors of this report and to their mentor, Jay Forrester, goes the merit of having identified for the first time the critical problem that we are facing nowadays, that of “overshoot”, exceeding the limits that the planetary ecosphere can sustain and forcing humankind to a return within the limits that could be painful or even disastrous. 
Today, the Club of Rome keeps following its tradition of studying the long-term prospects of humankind facing the twin challenges of resource depletion and climate change. The latest report of the Club on these matters is “Come On” by Anders Wijkman and Ernst Von Weizsacker, published with Springer in 2017, in occasion of the 50th anniversary of the foundation of the Club. 
Clearly, this is a book which has been thoroughly planned and carefully created. The text is divided into three parts: 1) A review of the currently unsustainable trends, 2) A review of how to look at the situation 3) A discussion of solutions designed to avoid disaster. It is a sort of Aristotelian syllogism structure. 
The first part, the review of the current trends, is – in my opinion – the best part of the book. It is a well thought-out review which doesn’t shun from facing some politically unnameable subjects, such as that of overpopulation and of the need to stop its growth. The unsustainable nature of the current agricultural system is also discussed in detail here. This section is also an excellent summary of the results of the first version of “The Limits to Growth” and how the scenarios of that early work have played out in our world. The “Come on!” here, refers to how obvious all this should be, but it isn’t in the current debate. 
The second part of the book is a review of the theories and models currently used to understand the situation in which we find ourselves. This section provides a description of religious views of the relation of humankind with the world, starting with the Pope’s encyclical letter “Laudato si” and then moves to a detailed criticism of the current economic theories. It includes also a very interesting section on the moral imperative of change and on the need of a “new enlightenment” rather than a “new rationalism.” It is correctly recognized that a purely rational choice is often framed in a short-term vision and it may lead to effects opposite to those intended. 
In this second section, the “Come On” is referred to the need of not sticking to outdated but still current philosophies, especially in economics. It is what the authors call a "mind shift," that we may describe in terms of the often mentioned (although probably apocryphal) quote by Albert Einstein, "we cannot solve problems with the same thinking that created them.” This is the context in which the quest for a new enlightenment should be seen. A fundamental element of this vision is the circular economy, returning to the ecosystem what we took from the ecosystem. It is a concept that's making inroads in the debate, but much work remains to be done to make it real and not just an empty slogan. 
Finally, the third part of the book. This is the most ambitious section, indeed it is as long as the first two summed together. It is also the most difficult and complex: what to do, in practice? Here, the authors face a problem that has affected the Club’s analysis over the past 50 years: who should act to save humankind from destruction? 
The initial attitude of the Club on this point was heavily influenced by the personality of the Club’s founder, Aurelio Peccei. In the 1960s, Peccei had developed a vision that saw humankind as an ekklesia, a gathering of free and equal citizens of the world. As a consequence, the Club tended to propose actions that were to be agreed upon by all the citizens of the Earth by means of a democratic process. It was a top-down vision, in the sense that it implied that the choices made by the people were to be enforced by some kind of world government, or at least by an association of all the existing governments. 
As we all know, this approach has not worked. Peccei was misunderstood and the Club of Rome was accused of planning a world dictatorship and all sorts of nefarious actions, including even a new holocaust designed for population control. It was all false. As you can read in my book "The Limits to Growth Revisited," it was just propaganda, but it turned out to be effective in demonizing the Club of Rome and protecting the special interests of various lobbies. But then, what to do? 
50 years after that first report, the authors of “Come On” describe a different approach, basically focused on the “bottom-up” strategy. This choice appears most clearly in the third section of the book, which is dedicated to practical, implementable solutions, such as agro-ecology, the blue economy, regenerative urbanization, benign investments, and much more. The basic idea is always the same: do not force people not to do something with laws coming from a government (top-down). Encourage them to choose to do something for their own benefit (bottom-up). 
For instance, instead of forcing people to emit less CO2, encourage them to use technologies which don’t emit it and that make people save money. Or help people seeing the economic advantages of waste recycling. Or show them how they can save money by using the public transportation system instead of private cars. Here, the "Come on" statement refers to pushing people to overcome their inertia and stop sticking to their old ways simply because they never thought there were other ways of doing the same things. 
The third chapter goes on for about 100 pages and I won’t try to summarize it here – it is surely worth reading for the wealth of ideas it carries. But will this approach work? The answer remains unclear. If we compare the "top-down" and the "bottom-up" approaches, we see that neither has done much to stop the ongoing unsustainable trends. Decades of attempts of setting up top-down international treaties to reduce, for instance, the overexploitation of resources has brought very little in terms of results - for instance, the CO2 emissions keep increasing. On the other hand, the bottom- up approach is successful in some areas, but not with most people. Just as an example, it would seem strange that people buy the expensive and useless vehicles called "SUVs." It is not a rational choice, one feels like telling SUV owners something like "come on, why are you wasting your money in this way?" Yet - today - about one car in three sold in Western countries is an SUV. The fact that some people choose to use bicycles, instead, doesn't change the situation. 
All this doesn't mean that the world is not changing, just that it is not changing fast enough (and this can be quantitatively demonstrated). It means, also, that we have to keep pushing for the change to occur in the right direction. Probably, neither a purely bottom-up nor a purely top-down approach can save humankind. We need an integrated approach. The "Come on" book is a step in the right direction.

Can we move to renewables fast enough? March 10, 2018.
Just a few years ago, there was ground to be optimistic about the energy transition. Renewable energy production showed a robust growth and the same happened for investments. If the trend could have continued, renewables would have swamped away fossil fuels easily and seamlessly. 
Instead, something went wrong in 2012. The growth of investments stalled, it went up and down for a few years and, by now, it is clear that it has plateaued. Investments in renewable energy are not growing and we don't know if they will ever restart growing. 
While it is true that the prices of renewable energy are going down, at these investment rates it is clear that we can't go through the transition fast enough to comply with the Paris targets. Possibly, we won't even be able to replace fossil fuels before they become too costly to produce. This is the result that myself and my coworkers Csala and Sgouridis obtained two years ago. According to our calculations, humankind would need to invest at least ten times as much, likely much more, in terms of energy to go through the transition fast enough. 
In his talk, Gregor Semeniuk showed other estimates confirming that the investment rates in renewables are not sufficient for what we need to do. The gist of his presentation was that if governments don't intervene, the transition will not happen fast enough. He showed several examples of past transitions which took place mainly because they were driven by the resources provided by the state.You can find the hugely interesting paper on these matters by Mazzucato and Semieniuk on "Technological Forecasting and Social Change" and also more material at this link
There remains the fundamental problem: how do we increase investments in renewable energy? Our faith in the free market is not helping us in this issue.

What if we could REALLY convince the public that climate change is a threat? Feb. 5, 2018.
Maybe one day some really gigantic-awful-horrible-monstrous-humungous climate related disaster will hit us. And that, at that moment, people will stop playing the boiling frog and will be forced to admit that climate change is real and we have to do something about that.

Unfortunately, plenty of gigantic-horrible-etc. disasters have already hit us, but the public doesn't seem to have taken notice. But never mind, we might be hit by the really big one. And, if it happens, do you think people will come to the scientists and tell them "we are so sorry, now we understand you were right all along"?

I have the impression that it will be rather something like what you see in the clip, below. It will be something like what the woman says, "God is going to destroy this Earth and there is nothing you silly scientists can do about that with all your scientific blah-blah."

And I have this terrible feeling that she may be right.


How Big a Disaster Can Climate Change Be? Feb. 2, 2018.

Above, you can see an image from the paper by Marsicek et al., just appeared on Nature. It shows a reconstruction from pollen records of the temperatures of the past 10,000 year or so, the "Holocene," for North America and Europe. Note the black squares, showing how fast temperatures have been growing during the past 50 years or so. 
As all reconstructions of the past, this one has to be taken with some caution, but it fits well with the various "hockey sticks" that research continues to produce despite the attempts to discredit both the science and the scientists who work in this field. So, we can assume these results to be reasonably reliable. Then, we can note a few interesting things. 
1. What we call "civilization" arose and continued to exist during a period of relatively constant temperatures, that is, during the past 5000 years or so. During this period, the oscillations in the graph are never more than about half a degree. That's probably not a coincidence. Agriculture and civilization come together and it is unlikely that agriculture could have been developed for wildly oscillating temperatures and rapidly varying climates 
2. Civilizations seem to grow and collapse because of internal factors - the fall of empires doesn't seem to be correlated to climate change. For instance, you can look in the graph for the data corresponding to the fall of the Roman Empire, between 2000 and 1500 years ago. Temperatures are flat, at most cooling a little. It is a point that I already made on the basis of another set of data specific for the region occupied by the Roman Empire. These more detailed data show a cooling period in Europe, but after the fall of the Empire.

3. Some relatively intense oscillations in the curve appear at about 3000 years bp, which corresponds to the collapse of the Late Bronze Age civilization. This might support the interpretation by Eric Cline who sees climate as a concause of the collapse. Maybe, but can a whole civilization collapse abruptly as the result of a temperature change of just a couple of tenths of degrees? Personally, I tend to think the opposite. That is, the modest temperature change of the Late Bronze Age has been triggered by the collapse of the Mediterranean civilization of that time.

4. Note how some much touted events of the past - for instance the "Medieval Warm Period" - appear as just minor perturbations in the curve. Overall, it seems that the effect of human activity on climate has been marginal until the age of fossil fuels
5. According to Ruddiman, the relative stability of the past 8000 years or so is the result of the release of greenhouse gases produced by human agriculture. This is the phenomenon which prevented the earth system to return to a new ice age. It is possible, but it seems to me at least unlikely that a system can be stabilized by two opposite strong perturbations (the other one is the effect of the Milankovitch oscillations)

6. There is no obvious correlation of this long term trend with what we know of the Sun's output. There has been a lot of speculation that the past temperature oscillations have been related to variations of the Sun's output -- the "Maunder Minimum" is an example of that. But if these variations have an effect, it is truly minimal. It can only be within the oscillations of the curve which don't exceed a few tenths of degree. 
7. The increase in temperatures during the past 50 years or so has been simply stunning. In a sense, these sudden temperature changes are not unusual in the earth's history (the problem for biological species is to survive them). But, in this case, it is so fast that it has probably no equals in the whole geological history of the planet. It is a disaster ongoing. Will civilization survive? Will humankind survive? Will anything alive today survive? Who can say?



A Seneca Collapse for the World’s Human Population? July 16, 2018.


By Ugo Bardi (a similar version has appeared in 2017 on "The Journal of Population and Sustainability")

1. Introduction

The world has enough for every man's need, but not enough for every man's greed.” Gandhi
 
While Gandhi's observation about greed remains true even today, it may not be so for the ability of the world to meet every man's need. Gandhi is reported to have said that in 1947 when the world population was under 2.5 billion, about one-third of the current figure of 7.5 billion. And it keeps growing. Does the world still have enough for every man’s need? 
It is a tautology that if there are 7.5 billion people alive on planet earth today there must exist sufficient resources to keep them alive. The problem is for how long: a question rarely taken into account in estimates purportedly aimed at determining the maximum human population that the Earth can support. 
The problem of long-term support of a population can be expressed in terms of the concept of “overshoot,” applied first by Jay Forrester in 1972 [2] to social systems. The innovative aspect of Forrester's idea is that it takes the future into consideration: if there is enough food for 7.5 billion people today, that doesn’t mean that the situation will remain the same in the future. The destruction of fertile soil, the depletion of aquifers, the increased reliance on depletable mineral fertilizers, to say nothing of climate change, are all factors that may make the future much harder than it is nowadays for humankind. The problems will be exacerbated if the population continues to grow. 
So, will the human population keep growing in the future as it has in the past? Many demographic studies have attempted to answer this question, often arriving at widely different results. Some studies assume that population will keep growing all the way to the end of the current century, others that it will stabilize at some value higher than the present one, others still that it will start declining in the near future. Few, if any, studies have taken into account the phenomenon of rapid decline that I have termed “Seneca Effect” (or “Seneca Collapse”) [3]⁠, from a sentence written during the 1st century AD by the Roman philosopher Lucius Annaeus Seneca. 
The Seneca Collapse is a phenomenon affecting complex systems where strong feedback relationships link the elements of the system to each other. Biological communities where predators and their prey are linked to each other are a good example of these systems. The Seneca Effect describes a situation in which the feedbacks of the system act together to generate a rapid decline of some of the stocks (populations) of the system. The typical “Seneca Curve” (or "Seneca Cliff") is shown in the figure below



Figure 1. A typical “Seneca Curve” calculated by means of system dynamics. It shows how decline can be faster than growth  
In the following, I'll list a series of examples showing that the Seneca Curve is relatively common in biological systems, including for historical human population. The possibility of an upcoming Seneca Cliff affecting humankind in the near future is real....
... 
4. Conclusion

All biological populations need food and are affected by predation. Wild populations have no internal mechanisms to plan ahead and the result is normally what we call “overshoot,” where the population grows over the limits which the resources can sustain over a long time and finally collapses. The result is population curves which take the typical "Seneca Shape" described in [3]
The future of the world’s human population may well be described in similar terms, that is decline caused by overshoot, predation, or birth control. Of the three, predation could take the form of a microbial infection spreading all over the world and killing a substantial fraction of the human population. Another likely effect is overshoot, especially in terms of the decline of the world's agriculture or, more simply, to the loss of the capability of the globalized economic system to deliver it worldwide.


In Support of a Physics-Based Energy Transition Planning: Sowing Our Future Energy Needs. Ugo Bardi & Sgouris Sgouridis, Economics and Resource Quality. December 2017.

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