As Night Closes by

Plenty of books in the 1970s and early 1980s applied the lessons of ecology to the future of industrial civilization and picked up at least part of the bad news that results. Overshoot was arguably the best of the lot, but it was pretty much guaranteed to land even deeper in the memory hole than the others. The difficulty was that [William R.] Catton’s book didn’t pander to the standard mythologies that still beset any attempt to make sense of the predicament we’ve made for ourselves; [...] he explained how industrial civilization was cutting its own throat, how far past the point of no return we’d already gone, and what had to be done in order to salvage anything from the approaching wreck.

The core of Overshoot, which is also the core of the entire world of appropriate technology and green alternatives that got shot through the head and shoved into an unmarked grave in the Reagan years, is the recognition that the principles of ecology apply to industrial society just as much as they do to other communities of living things. It’s odd, all things considered, that this is such a controversial proposal. [...] human societies are as subject to the laws of ecology as they are to every other dimension of natural law.

Let’s start with the basics. Every ecosystem, in thermodynamic terms, is a process by which relatively concentrated energy is dispersed into diffuse background heat. Here on Earth, at least, the concentrated energy mostly comes from the Sun, in the form of solar radiation—there are a few ecosystems, in deep oceans and underground, that get their energy from chemical reactions driven by the Earth’s internal heat instead. Ilya Prigogine showed some decades back that the flow of energy through a system of this sort tends to increase the complexity of the system; Jeremy England, a MIT physicist, has recently shown that the same process accounts neatly for the origin of life itself. The steady flow of energy from source to sink is the foundation on which everything else rests. The complexity of the system, in turn, is limited by the rate at which energy flows through the system, and this in turn depends on the difference in concentration between the energy that enters the system, on the one hand, and the background into which waste heat diffuses when it leaves the system, on the other. 

 

Simple as it is, it’s a point that an astonishing number of people—including some who are scientifically literate—routinely miss. [...] one of the core reasons you can’t power a modern industrial civilization on solar energy is that sunlight is relatively diffuse as an energy source, compared to the extremely concentrated energy we get from fossil fuels. [...] Nature has done astonishing things with that very modest difference in concentration. People who insist that photosynthesis is horribly inefficient, and of course we can improve its efficiency, are missing a crucial point: something like half the energy that reaches the leaves of a green plant from the Sun is put to work lifting water up from the roots by an ingenious form of evaporative pumping [...] all told, a green plant is probably about as efficient in its total use of solar energy as the laws of thermodynamics will permit.

That said, there are hard upper limits to the complexity of the ecosystem that these intricate processes can support. You can see that clearly enough by comparing a tropical rain forest to a polar tundra. The two environments may have approximately equal amounts of precipitation over the course of a year; they may have an equally rich or poor supply of nutrients in the soil; even so, the tropical rain forest can easily support fifteen or twenty thousand species of plants and animals, and the tundra will be lucky to support a few hundred. Why? The same reason Mercury is warmer than Neptune: the rate at which photons from the sun arrive in each place per square meter of surface.

Near the equator, the sun’s rays fall almost vertically.  Close to the poles, since the Earth is round, the Sun’s rays come in at a sharp angle, and thus are spread out over more surface area. The ambient temperature’s quite a bit warmer in the rain forest than it is on the tundra, but because the vast heat engine we call the atmosphere pumps heat from the equator to the poles, the difference in ambient temperature is not as great as the difference in solar input per cubic meter. Thus ecosystems near the equator have a greater difference in energy concentration between input and output than those near the poles, and the complexity of the two systems varies accordingly.

All this should be common knowledge. Of course it isn’t, because the industrial world’s notions of education consistently ignore what William Catton called “the processes that matter”—that is, the fundamental laws of ecology that frame our existence on this planet—and approach a great many of those subjects that do make it into the curriculum in ways that encourage the most embarrassing sort of ignorance about the natural processes that keep us all alive.

A human society is an ecosystem.  Like any other ecosystem, it depends for its existence on flows of energy, and as with any other ecosystem, the upper limit on its complexity depends ultimately on the difference in concentration between the energy that enters it and the background into which its waste heat disperses. (This last point is a corollary of White’s Law, one of the fundamental principles of human ecology, which holds that a society’s economic development is directly proportional to its consumption of energy per capita.)  Until the beginning of the industrial revolution, that upper limit was not much higher than the upper limit of complexity in other ecosystems, since human ecosystems drew most of their energy from the same source as nonhuman ones: sunlight falling on green plants.

The discoveries that made it possible to turn fossil fuels into mechanical energy transformed that equation completely. The geological processes that stockpiled half a billion years of sunlight into coal, oil, and natural gas boosted the concentration of the energy inputs available to industrial societies by an almost unimaginable factor, without warming the ambient temperature of the planet more than a few degrees, and the huge differentials in energy concentration that resulted drove an equally unimaginable increase in complexity. Choose any measure of complexity you wish—number of discrete occupational categories, average number of human beings involved in the production, distribution, and consumption of any given good or service, or what have you—and in the wake of the industrial revolution, it soared right off the charts. Thermodynamically, that’s exactly what you’d expect.

The difference in energy concentration between input and output, it bears repeating, defines the upper limit of complexity. Other variables determine whether or not the system in question will achieve that upper limit. In the ecosystems we call human societies, knowledge is one of those other variables. If you have a highly concentrated energy source and don’t yet know how to use it efficiently, your society isn’t going to become as complex as it otherwise could. Over the three centuries of industrialization, as a result, the production of useful knowledge was a winning strategy, since it allowed industrial societies to rise steadily toward the upper limit of complexity defined by the concentration differential. The limit was never reached—the law of diminishing returns saw to that—and so, inevitably, industrial societies ended up believing that knowledge all by itself was capable of increasing the complexity of the human ecosystem. Since there’s no upper limit to knowledge, in turn, that belief system drove what Catton called the cornucopian myth, the delusion that there would always be enough resources if only the stock of knowledge increased quickly enough.

That belief only seemed to work, though, as long as the concentration differential between energy inputs and the background remained very high. Once easily accessible fossil fuels started to become scarce, and more and more energy and other resources had to be invested in the extraction of what remained, problems started to crop up. Tar sands and oil shales in their natural form are not as concentrated an energy source as light sweet crude—once they’re refined, sure, the differences are minimal, but a whole system analysis of energy concentration has to start at the moment each energy source enters the system. Take a cubic yard of tar sand fresh from the pit mine, with the sand still in it, or a cubic yard of oil shale with the oil still trapped in the rock, and you’ve simply got less energy per unit volume than you do if you’ve got a cubic yard of light sweet crude fresh from the well, or even a cubic yard of good permeable sandstone with light sweet crude oozing out of every pore.

It’s an article of faith in contemporary culture that such differences don’t matter, but that’s just another aspect of our cornucopian myth. The energy needed to get the sand out of the tar sands or the oil out of the shale oil has to come from somewhere, and that energy, in turn, is not available for other uses. The result, however you slice it conceptually, is that the upper limit of complexity begins moving down. That sounds abstract, but it adds up to a great deal of very concrete misery, because as already noted, the complexity of a society determines such things as the number of different occupational specialties it can support, the number of employees who are involved in the production and distribution of a given good or service, and so on. There’s a useful phrase for a sustained contraction in the usual measures of complexity in a human ecosystem: “economic depression.”

The economic troubles that are shaking the industrial world more and more often these days, in other words, are symptoms of a disastrous mismatch between the level of complexity that our remaining concentration differential can support, and the level of complexity that our preferred ideologies insist we ought to have. As those two things collide, there’s no question which of them is going to win. Adding to our total stock of knowledge won’t change that result, since knowledge is a necessary condition for economic expansion but not a sufficient one: if the upper limit of complexity set by the laws of thermodynamics drops below the level that your knowledge base would otherwise support, further additions to the knowledge base simply mean that there will be a growing number of things that people know how to do in theory, but that nobody has the resources to do in practice.

Knowledge, in other words, is not a magic wand, a surrogate messiah, or a source of miracles. It can open the way to exploiting energy more efficiently than otherwise, and it can figure out how to use energy resources that were not previously being used at all, but it can’t conjure energy out of thin air. Even if the energy resources are there, for that matter, if other factors prevent them from being used, the knowledge of how they might be used offers no consolation—quite the contrary.

That latter point, I think, sums up the tragedy of William Catton’s career. He knew, and could explain with great clarity, why industrialism would bring about its own downfall, and what could be done to salvage something from its wreck. That knowledge, however, was not enough to make things happen; only a few people ever listened, most of them promptly plugged their ears and started chanting “La, la, la, I can’t hear you” once Reagan made that fashionable, and the actions that might have spared all of us a vast amount of misery never happened. -- John Michael Greerref