The Age of Limits

by Orren Whiddon
First published
in 2006

“To those who followed Columbus and Cortez, the New World truly seemed incredible because of the natural endowments. The land often announced itself with a heavy scent miles out into the ocean. Giovanni da Verrazano in 1524 smelled the cedars of the East Coast a hundred leagues out. The men of Henry Hudson’s Half Moon were temporarily disarmed by the fragrance of the New Jersey shore, while ships running farther up the coast occasionally swam through large beds of floating flowers. Wherever they came inland they found a rich riot of color and sound, of game and luxuriant vegetation. Had they been other than they were, they might have written a new mythology here. As it was, they took inventory.”

Frederick Turner


Hydrocarbon and Natural Resource Depletion. Global Warming and Climate Change. Population Maximum. Debt Economics and Globalism. Water Wars and Permanent Drought. The Age of Limits. Peak Everything.

Over the past two decades these issues have moved from the discussion of specialists, into public consciousness and policy discourse. It would seem that we are facing “The Perfect Storm” of separate global problems, when in fact they are symptoms of a unifying core issue.

As a species we have developed a “kit bag” of social and technical strategies that has expanded from its historical European origins to become, since World War II, the consensus adaptation of global society. These strategies are based on the scientific exploitation of natural resources to the end of increasing the physical wealth accessible by humans, and as such we have been enormously successful. We have purposefully engineered the exponential growth of world population and industrial output through our ability to convert stored geological resources into the “living stuffs” required and desired by our species. As basic measures of that exponential growth, our world population has almost doubled to 7 billion in the past 40 years and the sheer mass of physical “living stuff” we have produced and consumed in that 40 year period is greater than that produced in all of our preceding human history.

In popular culture, this growth has been heralded as a triumph of global free markets and technical innovation. A rising tide that has increased the physical well being of an ever-increasing world population. And so it has. 

But environmental systems scientists have pointed out a simple and profound truth. That while nature has many biological processes that experience periods of exponential growth, it has no examples of growth without limit. In biological systems, all examples of exponential growth encounter ultimate limits immutably defined by the original physical resources in place.

If the rate of resource consumption exceeds the rate of replenishment, the population of the system is said to be in “Over Shoot” of the system's “Carrying Capacity.” If that population is also in a period of exponential growth, it can only experience a sudden “Die Off” of population levels, before reaching a much smaller level where consumption is in again balance with available resources.

The cold reality of the exponential function when applied to our species growth, is that we have already maximized the production levels of all the worlds finite physical resources to serve our experiment of global industrial culture. There are no remaining super-giant oil fields to be discovered, no new iron or phosphate mines to be opened, no continental river systems still to be exploited for the irrigation of deserts. One half of all the hydrocarbons consumed in the history of human kind have been consumed in the past 25 years. Per capita global grain stocks have fallen from 180 days supply, to 50 days supply in those same 25 years.

As a biological system in overshoot, we are now encountering the physical limits that will define the end of our species period of exponential growth, and the subsequent decline to a sustainable, zero growth future. 

A common theme of Indigenous and Earth Based Spirituality is that “We are all part of the Web of Life. We are all Connected.” On its surface this may seem a platitude, but for the world wide industrial culture of today it is a fundamental physical truth. Life is truly a Circle, with no beginning and no ending. And to live is to exist within the Circle, and to be constrained by its bounds.

Our consumer culture protests that our technology makes us an exception to natural law. But we are in fact living creatures making up a biological system, and we are an indivisible part of the web of life. Although god-like in our power, we remain subject to the same balance of forces as the proverbial Foxes and Rabbits, or the less poetic but even more illustrative yeast culture in a Petrie dish. We have followed the universal imperative of all life to exploit a vast base of resources deposited over geological time scales. And as all life will, we have used those resources to expand our numbers, to fill every ecological niche, to take advantage of every energy flow available to us. We are life and we have cast a wide web indeed.

So it’s not global this or peak whatever that is the problem. They are symptoms. In fact they are the correctives that Nature is applying in order to bring the global system back into balance. It’s not a problem to be “solved,” as much as it is recognizing that we as individuals, as well as our global industrial culture, are subject to the universal life processes of growth, sustain, decay and release. Like the Foxes, the Rabbits and Yeast; our industrial species has expanded its numbers beyond the carrying capacity of the resource base and has been in a formal condition of ecological overshoot for decades. Nature will always act to bring an out of balance system back into balance, though the end point of balance may be far removed from the origin. We are now beginning to experience the means through which natural processes are returning our system to balanced sustainability, though these means may strike us as unpleasant, if not brutal.

Hydrocarbon and Natural Resource Depletion. Global Warming and Climate Change.  Population Maximum. Debt Economics and Globalism. Water Wars and Permanent Drought. The Age of Limits. Peak Everything.

To overshoot means to go too far, to grow so large so quickly that limits are exceeded. When an overshoot occurs, it induces stresses that begin to slow and stop growth. The three causes of overshoot are always the same, at any scale from personal to planetary. First, there is growth, acceleration, rapid change. Second, there is some form of limit or barrier, beyond which the moving system may not safely go. Third, there is a delay or mistake in the perceptions and the responses that try to keep the system within its limits. The delays can arise from inattention, faulty data, a false theory about how the system responds, deliberate efforts to mislead, or from momentum that prevents the system from being stopped quickly.”

- Limits to Growth, The 30 Year Update -
- Donella Meadows, 2004

ln biological systems, access to resources drives, and limits, population growth. We can gain rough insight into the past timing of environmental over shoot and the onset of future decline and die off by examining the metrics of three interrelated measures of our own exponential growth. Liquid Petroleum Production, World Grain Stocks and World Population.


  • In 2009 world liquids production is about 32 billon barrels a year (Gb/a). 25 years earlier, 1985 production was 22 Gb/a. 1960 production was 8 Gb/a. 1935 production was 2 Gb/a.
  • One half of all petroleum produced has been consumed in the past 25 years.
  • Land based conventional petroleum constitutes 75% of global production, reached peak production in 2005 and is now declining at about 4% a year.
  • Deep Sea, Arctic and Natural Gas Liquids are 25% of global production, 10% of global reserves and will see steep decline rates after they reach peak production.

Petroleum production growth was purely exponential until the 1980s at which point production growth rates began leveling off, having presently reached essentially peak production and zero growth. Population growth rates have remained exponential, as they are literally “fueled” by hydrocarbons and the physical wealth that hydrocarbons make possible in every other area of resource extraction and wealth production.

Nowhere is this relationship more apparent than in the surge of per capita grain in storage that occurred after the development of the Green Revolution of the 1960s. Here food crops were specifically developed for their enhanced ability to transform the caloric content of petroleum derived synthetic fertilizers into human usable calories. The application of this technology was matched by the era’s exponential growth of petroleum production to produce a window of population growth unconstrained by its classic limit, available food.


  • Expressed as days of carrying capacity for global population, world grain stocks steadily decreased after World War II, declining to about 60 days capacity in the early 1970s.
  • The “Green Revolution” of food crops engineered to metabolize petroleum derived synthetic fertilizers temporarily arrested this decline.
  • Grain Carrying Capacity peaked in 1985 at 130 days per person and in 25 years has declined to 50 days per person

Since its introduction the Green Revolution has produced year by year increases in absolute quantities of food production, but those increases have been linear, not exponential. When overlayed by the food requirements of an exponentially increasing population, the amount of stored food available for each person reached a maximum of 130 days supply in the mid
1980s and has since fallen to less than 50 days per person supply in 2009. Additionally, the absolute quantities of food production are now reaching a plateau constrained by the availability of arable land and synthetic fertilizers. It should be noted that this plateau in total food production and fall in per capita grain storage is in relationship to the declining growth and current plateau in petroleum production. It is very likely that grain in storage per person will precipitously fall as world petroleum production enters its period of terminal decline.


  • World population in 1985 was about 5 billion and in 25 years has increased to 7 billion.
  • The UN medium case predicts a 25 year increase to 9 billion in 2035

These three measures provide an easily illustrated example of the interactive mechanisms of growth within a global industrial society, and they apply equally well to other core resources such as water, metal ores and mined agricultural phosphorus. As a biological system in the terminal phase of exponential growth we have been in a formal condition of ecological over shoot of global carrying capacity for decades. While petroleum production peaks in the near term, Green Revolution driven per capita grain stocks will continue to decline, that decline accelerated by continued population growth. At some point the trend lines will converge and we will enter the endpoint of all exponential biological growth. Decline and Die Off.


As a species, we have evolved to heavily discount future consequences in favor of the “low hanging fruit” of immediate gain. For a culture whose operational time scales are compressed to quarterly profit statements and four year election cycles, considerations of systemic change on the time scale of decades requires a profound shift in paradigm. It is an open question whether our governmental and social mechanisms can adapt behaviors to mitigate the decline in time to minimize damage to planetary ecological systems and to more humanely manage the impacts upon ourselves and our fellows. It can reasonably be argued that we are already well past the time in our history when, through the application of prescient governmental policy, we could mitigate some form of future global die off. If so, then certainly that window closed in the 1970s.

Ignoring that the effects of global warming, fresh water depletion and debtor economics can only accelerate the onset of decline; and confining ourselves to the relationships between petroleum, food and population; we can make an educated guess of our future time line. In 25 years a best case is that global petroleum production would be two thirds of todays peak levels. In 25 years the UN’s best case population estimate is for 8 billion persons. And if we make the very optimistic assumption that per capita grain stocks will decline at the same rate at which they increased during the Green Revolution, they will cross the zero line in about 25 years. Afterwards, the deluge.

These considerations are dire. They are also completely within the natural behavior of biological systems. The biological system of which we are a part is not a problem, but a process. A process of adaptation, chance and change.

Those of us in the West are the inheritors of the culture that invented the means of exponential growth through the exploitation of stored geological resources. And in North America we are by fortunate chance endowed with still to be exploited natural resources and a legacy of already  physically embodied “living stuff” created by our past industrial expansion. That is not to say  that the adaptations we will be forced to make over the coming decades will be easy, they most assuredly will be incredibly difficult. Standing at the zenith of The Age of Carbon Man, we have that much farther to fall. But it may be that we will avoid wide spread population die off while adapting to life with a vastly diminished resource footprint.

For most of the world's population no such cushion exists. Through economic globalization they have abandoned their traditional farming practices and the population limits those practices enforced, to chase the Ephemera of western industrial culture. Now completely dependent upon petroleum derived systems of agriculture and occupying increasingly marginal ecological niches; any permanent downturn in the availability of net resources will result in sudden crash, catastrophic change and population die off.

Morally, we must recognize that we North Americans are 5% of the world's population consuming 20% of its resource base. This ratio of resource dominion will not continue into the future, simply because resources have limits and producing regions in crisis will retain more of their limited production in support of their own populations. But it is likely we will use our power to maintain our relative position of dominance in consumption, and it is irreducible that any resource applied to maintaining our much higher standard of living is a resource denied to another. Our cultures continued consumption hastens the approach of the exponential maximum, with first effects to be suffered by those who, paradoxically, consume less.

At the other extreme, resources intentionally allocated to sustain the global wealth creation model, and maintain those populations at greatest risk, will have the end effect of promoting further increases in population, as well as accelerating global rates of resource depletion and planetary environmental degradation. These positive feedback loops prior to reaching exponential maximum will increase the ultimate numbers of people culled in global die off and the virulence of the natural mechanisms that emerge. In essence, the harder we work to postpone global die off, then the more devastating will be its eventual consequences, the greater will be the ecological damage sustained by the planet and the longer will be the recovery to ultimately sustainable population levels.

In this new Age of Limits we are presented with a moral choice, for which there is no moral answer.

Directions for the Journey

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Classic Authors
Limits to Growth: The 30-Year Update
-Donella Meadows 1974-2004
-William R. Catton 1982
The Collapse of Complex Societies
-Joseph Tainter 1990
The Party’s Over
-Richard Heinberg 2003
-Jared Diamond 2005
Reinventing Collapse
-Dmitry Orlov 2006
Plan B 3.0: Mobilizing to Save Civilization
-Lester R. Brown 2008