Category Archives: Limits

Species Restoration & Policy Resistance

I’ve seen a lot of attention lately to restoration of extinct species. It strikes me as a band-aid, not a solution.

Here’s the core of the system:

speciesReintroCritters don’t go extinct for lack of human intervention. They go extinct because the balance of birth and death rates is unfavorable, so that population declines, and (stochastically) winks out.

That happens naturally of course, but anthropogenic extinctions are happening much faster than usual. The drivers (red) are direct harvest and loss of the resource base on which species rely. The resource base is largely habitat, but also other species and ecosystem services that are themselves harvested, poisoned by pollutants, etc.

Reintroducing lost species may be helpful in itself (who wouldn’t want to see millions of passenger pigeons?), but unless the basic drivers of overharvest and resource loss are addressed, species are reintroduced into an environment in which the net gain of births and deaths favors re-extinction. What’s the point of that?

If the drivers of extinction – ultimately population and capital growth plus bad management – were under control, we wouldn’t need much restoration. If they’re out of control, genetic restoration seems likely to be overwhelmed, or perhaps even to contribute to problems through parachuting cats side effects.

speciesReintro2This is not where I’d be looking for leverage.

Fixed and Variable Limits

After I wrote my last post, it occurred to me that perhaps I should cut Ellis some slack. I still don’t think most people who ponder limits think of them as fixed. But, as a kind of shorthand, we sometimes talk about them that way. Consider my slides from the latest SD conference, in which I reflected on World Dynamics,

It would be easy to get the wrong impression here.

Of course, I was talking about World Dynamics, which doesn’t have an explicit technology stock – Forrester considered technology to be part of the capital accumulation process. That glosses over an important point, by fixing the ratios of economic activity to resource consumption and pollution. World3 shares this limitation, except in some specific technology experiments.

So, it’s really no wonder that, in 1973, it was hard to talk to economists, who were operating with exogenous technical progress (the Solow residual) and substitution along continuous production functions in mind.

Unlimited or exogenous technology doesn’t really make any more sense than no technology, so who’s right?

As I said last time, the answer boils down to whether technology proceeds faster than growth or not. That in turn depends on what you mean by “technology”. Narrowly, there’s fairly abundant evidence that the intensity (per capita or GDP) of use of a variety of materials is going down more slowly than growth. As a result, resource consumption (fossil fuels, metals, phosphorus, gravel, etc.) and persistent pollution (CO2, for example) are increasing steadily. By these metrics, sustainability requires a reversal in growth/tech trend magnitudes.

But taking a broad view of technology, including product scope expansions and lifestyle, what does that mean? The consequences of these material trends don’t matter if we can upload ourselves into computers or escape to space fast enough. Space doesn’t look very exponential yet, and I haven’t really seen credible singularity metrics. This is really the problem with the Marchetti paper that Ellis links, describing a global carrying capacity of 1 trillion humans, with more room for nature than today, living in floating cities. The question we face is not, can we imagine some future global equilibrium with spectacular performance, but, can we get there from here?

Nriagu, Tales Told in Lead, Science

For the Romans, there was undoubtedly a more technologically advanced  future state (modern Europe), but they failed to realize it, because social and environmental feedbacks bit first. So, while technology was important then as now, the possibility of a high tech future state does not guarantee its achievement.

For Ellis, I think this means that he has to specify much more clearly what he means by future technology and adaptive capacity. Will we geoengineer our way out of climate constraints, for example? For proponents of limits, I think we need to be clearer in our communication about the technical aspects of limits.

For all sides of the debate, models need to improve. Many aspects of technology remain inadequately formulated, and therefore many mysteries remain. Why does the diminishing adoption time for new technologies not translate to increasing GDP growth? What do technical trends look like when measured by welfare indices rather than GDP? To what extent does social IT change the game, vs. serving as the icing on a classical material cake?

Are there limits?

Several people have pointed out Erle Ellis’ NYT opinion, Overpopulation Is Not the Problem:

MANY scientists believe that by transforming the earth’s natural landscapes, we are undermining the very life support systems that sustain us. Like bacteria in a petri dish, our exploding numbers are reaching the limits of a finite planet, with dire consequences. Disaster looms as humans exceed the earth’s natural carrying capacity. Clearly, this could not be sustainable.

This is nonsense.

There really is no such thing as a human carrying capacity. We are nothing at all like bacteria in a petri dish.

In part, this is just a rhetorical trick. When Ellis explains himself further, he says,

There are no environmental/physical limits to humanity.

Of course our planet has limits.

Clear as mud, right?

Here’s the petri dish view of humanity:

I don’t actually know anyone working on sustainability who operates under this exact mental model; it’s substantially a strawdog.

What Ellis has identified is technology.

Yet these claims demonstrate a profound misunderstanding of the ecology of human systems. The conditions that sustain humanity are not natural and never have been. Since prehistory, human populations have used technologies and engineered ecosystems to sustain populations well beyond the capabilities of unaltered “natural” ecosystems.

Well, duh.

The structure Ellis adds is essentially the green loops below:

Of course, the fact that the green structure exists does not mean that the blue structure does not exist. It just means that there are multiple causes competing for dominance in this system.

Ellis talks about improvements in adaptive capacity as if it’s coincident with the expansion of human activity. In one sense, that’s true, as having more agents to explore fitness landscapes increases the probability that some will survive. But that’s a Darwinian view that isn’t very promising for human welfare.

Ellis glosses over the fact that technology is a stock (red) – really a chain of stocks that impose long delays:

With this view, one must ask whether technology accumulates more quickly than the source/sink exhaustion driven by the growth of human activity. For early humans, this was evidently possible. But as they say in finance, past performance does not guarantee future returns. In spite of the fact that certain technical measures of progress are extremely rapid (Moore’s Law), it appears that aggregate technological progress (as measured by energy intensity or the Solow residual, for example) is fairly slow – at most a couple % per year. It hasn’t been fast enough to permit increasing welfare with decreasing material throughput.

Ellis half recognizes the problem,

Who knows what will be possible with the technologies of the future?

Somehow he’s certain, even in absence of recent precedent or knowledge of the particulars, that technology will outrace constraints.

To answer the question properly, one must really decompose technology into constituents that affect different transformations (resources to economic output, output to welfare, welfare to lifespan, etc.), and identify the social signals that will guide the development of technology and its embodiment in products and services. One should interpret technology broadly – it’s not just knowledge of physics and device blueprints; it’s also tech for organization of human activity embodied in social institutions.

When you look at things this way, I think it becomes obvious that the kinds of technical problems solved by neolithic societies and imperial China could be radically different from, and uninformative about, those we face today. Further, one should take the history of early civilizations, like the Mayans, as evidence that there are social multipliers that enable collapse even in the absence of definitive physical limits. That implies that, far from being irrelevant, brushes with carrying capacity can easily have severe welfare implications even when physical fundamentals are not binding in principle.

The fact that carrying capacity varies with technology does not free us from the fact that, for any given level of technology, it’s easier to deliver a given level of per capita welfare to fewer people rather than more. So the only loops that argue in favor of a larger population involve the links from population to increase learning and adaptive capacity (essentially Simon’s Ultimate Resource hypothesis). But Ellis doesn’t present any evidence that population growth has a causal effect on technology that outweighs its direct material implications. So, one might much better say, “overpopulation is not the only problem.”

Ultimately, I wonder why Ellis and many others are so eager to press the “no limits” narrative.

Most people I know who believe that limits are relevant are essentially advocating internalizing the externalities that comprise failure to recognize limits, to guide market allocations, technology and preferences in a direction that avoids constraints. Ellis seems to be asking for an emphasis on the same outcome, technology or adaptive capacity to evade limits. It’s hard to imagine how one would get such technology without signals that promote its development and adoption. So, in a sense, both camps are pursuing compatible policy agendas. The difference is that proclaiming “no limits” makes it a lot harder to make the case for internalizing externalities. If we aren’t willing to make our desire to avoid limits explicit in market signals and social institutions, then we’re relying on luck to deliver the tech we need. That strikes me as a spectacular failure to adopt one of the major technical breakthroughs of our time, the ability to understand earth systems.

Update: Gene Bellinger replicated this in InsightMaker. Replication is a great way to force yourself to think deeply about a model, and often reveals insights and mistakes you’d never get otherwise (short of building the model from scratch yourself). True to form, Gene found issues. In the last diagram, there should be a link from population to output, and maybe consuming should be driven by output rather than capital, as it’s the use, not the equipment, that does the consuming.

There’s just enough time

In response to the question, “is there still time for a transition to sustainability,” John Sterman cited Donella Meadows,

The truth of the matter is that no one knows.

We have said many times that the world faces not a preordained future, but a choice. The choice is between different mental models, which lead logically to different scenarios. One mental model says that this world for all practical purposes has no limits. Choosing that mental model will encourage extractive business as usual and take the human economy even farther beyond the limits. The result will be collapse.

Another mental model says that the limits are real and close, and that there is not enough time, and that people cannot be moderate or responsible or compassionate. At least not in time. That model is self-fulfilling. If the world’s people choose to believe it, they will be proven right. The result will be collapse.

A third mental model says that the limits are real and close and in some cases below our current levels of throughput. But there is just enough time, with no time to waste. There is just enough energy, enough material, enough money, enough environmental resilience, and enough human virtue to bring about a planned reduction in the ecological footprint of humankind: a sustainabil­ity revolution to a much better world for the vast majority.

That third scenario might very well be wrong. But the evidence we have seen, from world data to global computer models, suggests that it could conceivably be made right. There is no way of knowing for sure, other than to try it.

Global modeling & C-ROADS

At the 2013 ISDC, John Sterman, Drew Jones and I presented a plenary talk on Global Models from Malthus to C-ROADS and Beyond. Our slides are in SDS 2013 Global Models Sterman Fid Jones.pdf and my middle section, annotated, is in SDS 2013 Global+ v12 TF excerpt.pdf.

There wasn’t actually much time to get into Malthus, but one thing struck me as I was reading his Essay on the Principle of Population. He identified the debate over limits as a paradigm conflict:

It has been said that the great question is now at issue, whether man shall henceforth start forwards with accelerated velocity towards illimitable, and hitherto unconceived improvement, or be condemned to a perpetual oscillation between happiness and misery, and after every effort remain still at an immeasurable distance from the wished-for goal.

Yet, anxiously as every friend of mankind must look forwards to the termination of this painful suspense, and eagerly as the inquiring mind would hail every ray of light that might assist its view into futurity, it is much to be lamented that the writers on each side of this momentous question still keep far aloof from each other. Their mutual arguments do not meet with a candid examination. The question is not brought to rest on fewer points, and even in theory scarcely seems to be approaching to a decision.

The advocate for the present order of things is apt to treat the sect of speculative philosophers either as a set of artful and designing knaves who preach up ardent benevolence and draw captivating pictures of a happier state of society only the better to enable them to destroy the present establishments and to forward their own deep-laid schemes of ambition, or as wild and mad-headed enthusiasts whose silly speculations and absurd paradoxes are not worthy the attention of any reasonable man.

The advocate for the perfectibility of man, and of society, retorts on the defender of establishments a more than equal contempt. He brands him as the slave of the most miserable and narrow prejudices; or as the defender of the abuses of civil society only because he profits by them. He paints him either as a character who prostitutes his understanding to his interest, or as one whose powers of mind are not of a size to grasp any thing great and noble, who cannot see above five yards before him, and who must therefore be utterly unable to take in the views of the enlightened benefactor of mankind.

In this unamicable contest the cause of truth cannot but suffer. The really good arguments on each side of the question are not allowed to have their proper weight. Each pursues his own theory, little solicitous to correct or improve it by an attention to what is advanced by his opponents.

Not much has changed in 200 years.

While much of the criticism of Limits to Growth remains completely spurious, and even its serious critics mostly failed to recognize that Limits discussed growth in material rather than economic/technological terms, I think the SD field missed some opportunities for learning and constructive dialog amid all the furor.

For example, one of the bitterest critics of Limits, William Nordhaus, wrote in 1974,

Economists have for the most part ridiculed the new view of growth, arguing that it is merely Chicken Little Run Wild. I think that the new view of growth must be taken seriously and analyzed carefully.

And he has, at least from the lens of the economic paradigm.

There are also legitimate technical critiques of the World3 model, as in Wil Thissen’s thesis, later published in IEEE Transactions, that have never been properly integrated into global modeling.

Through this failure to communicate, we find ourselves forty years down the road, without a sufficiently improved global model that permits exploration of both sides of the debate. Do exponential growth, finite limits, delays, and erosion of carrying capacity yield persistent overshoot and collapse, or will technology take care of the problem by itself?

Do social negative feedbacks achieve smooth adjustment?

I’m rereading some of the history of global modeling, in preparation for the SD conference.

From Models of Doom, the Sussex critique of Limits to Growth:

Marie Jahoda, Chapter 14, Postscript on Social Change

The point is … to highlight a conception of man in world dynamics which seems to have led in all areas considered to an underestimation of negative feedback loops that bend the imaginary exponential growth curves to gentler slopes than “overshoot and collapse”. … Man’s fate is shaped not only by what happens to him but also by what he does, and he acts not just when faced with catastrophe but daily and continuously.

Meadows, Meadows, Randers & Behrens, A Response to Sussex:

The Sussex group confuses the numerical properties of our preliminary World models with the basic dynamic attributes of the world system described in the Limits to Growth. We suggest that exponential growth, physical limits, long adaptive delays, and inherent instability are obvious, general attributes of the present global system.

Who’s right?

I think we could all agree that the US housing market is vastly simpler than the world. It lies within a single political jurisdiction. Most of its value is private rather than a public good. It is fairly well observed, dense with negative feedbacks like price and supply/demand balance, and unfolds on a time scale that is meaningful to individuals. Delays like the pipeline of houses under construction are fairly salient. Do these benign properties “bend the imaginary exponential growth curves to gentler slopes than ‘overshoot and collapse’”?

Kansas legislators fleece their grandchildren

File under “this would be funny if it weren’t frightening.”

HOUSE BILL No. 2366

By Committee on Energy and Environment

(a) No public funds may be used, either directly or indirectly, to promote, support, mandate, require, order, incentivize, advocate, plan for, participate in or implement sustainable development.

(2) “sustainable development” means a mode of human development in which resource use aims to meet human needs while preserving the environment so that these needs can be met not only in the present, but also for generations to come, but not to include the idea, principle or practice of conservation or conservationism.

Surely it’s not the “resource use aims to meet human needs” part that the authors find objectionable, so it must be the “preserving the environment so that these needs can be met … for generations to come” that they reject. The courts are going to have a ball developing a legal test separating that from conservation. I guess they’ll have to draw a line that distinguishes “present” from “generations to come” and declares that conservation is for something other than the future. Presumably this means that Kansas must immediately abandon all environment and resource projects with a payback time of more than a year or so.

But why stop with environment and resource projects? Kansas could simply set its discount rate for public projects to 100%, thereby terminating all but the most “present” of its investments in infrastructure, education, R&D and other power grabs by generations to come.

Another amusing contradiction:

(b) Nothing in this section shall be construed to prohibit the use of public funds outside the context of sustainable development: (1) For planning the use, development or extension of public services or resources; (2) to support, promote, advocate for, plan for, enforce, use, teach, participate in or implement the ideas, principles or practices of planning, conservation, conservationism, fiscal responsibility, free market capitalism, limited government, federalism, national and state sovereignty, individual freedom and liberty, individual responsibility or the protection of personal property rights;

So, what happens if Kansas decides to pursue conservation the libertarian way, by allocating resource property rights to create markets that are now missing? Is that sustainable development, or promotion of free market capitalism? More fun for the courts.

Perhaps this is all just a misguided attempt to make the Montana legislature look sane by comparison.

h/t Bloomberg via George Richardson

Zombies in Great Falls and the SRLI

The undead are rising from their graves to attack the living in Montana, and people are still using the Static Reserve Life Index.

The SRLI calculates the expected lifetime of reserves based on constant usage rate, as life=reserves/production. For optimistic gas reserves and resources of about 2200 Tcf (double the USGS estimate), and consumption of 24 Tcf/year (gross production is a bit more than that), the SRLI is about 90 years – hence claims of 100 years of gas.

How much natural gas does the United States have and how long will it last?

EIA estimates that there are 2,203 trillion cubic feet (Tcf) of natural gas that is technically recoverable in the United States. At the rate of U.S. natural gas consumption in 2011 of about 24 Tcf per year, 2,203 Tcf of natural gas is enough to last about 92 years.

Notice the conflation of SRLI as indicator with a prediction of the actual resource trajectory. The problem is that constant usage is a stupid assumption. Whenever you see someone citing a long SRLI, you can be sure that a pitch to increase consumption is not far behind. Use gas to substitute for oil in transportation or coal in electricity generation!

Substitution is fine, but increasing use means that the actual dynamic trajectory of the resource will show greatly accelerated depletion. For logistic growth in exploitation of the resource remaining, and a 10-year depletion trajectory for fields, the future must hold something like the following:

That’s production below today’s levels in less than 50 years. Naturally, faster growth now means less production later. Even with a hypothetical further doubling of resources (4400 Tcf, SRLI = 180 years), production growth would exhaust resources in well under 100 years. My guess is that “peak gas” is already on the horizon within the lifetime of long-lived capital like power plants.

Limits to Growth actually devoted a whole section to the silliness of the SRLI, but that was widely misinterpreted as a prediction of resource exhaustion by the turn of the century. So, the SRLI lives on, feasting on the brains of the unwary.

What a real breakthrough might look like

It’s possible that a techno fix will stave off global limits indefinitely, in a Star Trek future scenario. I think it’s a bad idea to rely on it, because there’s no backup plan.

But it’s equally naive to think that we can return to some kind of low-tech golden age. There are too many people to feed and house, and those bygone eras look pretty ugly when you peer under the mask.

But this is a false dichotomy.

Some techno/growth enthusiasts talk about sustainability as if it consisted entirely of atavistic agrarian aspirations. But what a lot of sustainability advocates are after, myself included, is a high-tech future that operates within certain material limits (planetary boundaries, if you will) before those limits enforce themselves in nastier ways. That’s not really too hard to imagine; we already have a high tech economy that operates within limits like the laws of motion and gravity. Gravity takes care of itself, because it’s instantaneous. Stock pollutants and resources don’t, because consequences are remote in time and space from actions; hence the need for coordination. Continue reading

The neo-cornucopians, live from planet Deepwater Horizon

On the heels of the 40th anniversary of Limits to Growth, the Breakthrough crowd is still pushing a technical miracle, just around the corner. Their latest editorial paints sustainability advocates as the bad guys:

Stop and think for a moment about the basic elements of the planetary boundaries hypothesis: apocalyptic fears of the future, a professed desire to return to an earlier state of nature, hypocrisy about wealth, appeals to higher authorities. These are the qualities of our worst religions, not our best scientific theories.

Who are these straw dog greenies, getting rich and ruling the world? Anyway, I thought the planetary boundaries were about biogeophysical systems, appealing to “higher authority” in that the laws of physics apply to civilizations too. Ted Nordhaus doesn’t believe it though:

To be sure, there are tipping points in nature, including in the climate system, but there is no way for scientists to identify fixed boundaries beyond which point human civilization becomes unsustainable for the simple reason that there are no fixed boundaries.

The Breakthrough prescription for the ills of growth is more growth: Continue reading