Preface. This post has two articles about overshoot, the actual crisis, not climate change which is just one of about a dozen symptoms (biodiversity loss, topsoil erosion, fresh water depletion, etc) that we’ve exceeded Earth’s carrying capacity. Yet all of our planning and discussion relentlessly and only focuses on CO2, and so as our little ship approaches the edge of overshoot we’ll be woefully prepared, making it much worse.

Alice Friedemann  www.energyskeptic.com  Author of Life After Fossil Fuels: A Reality Check on Alternative Energy; When Trucks Stop Running: Energy and the Future of Transportation”, Barriers to Making Algal Biofuels, & “Crunch! Whole Grain Artisan Chips and Crackers”.  Women in ecology  Podcasts: WGBH, Planet: Critical, Crazy Town, Collapse Chronicles, Derrick Jensen, Practical Prepping, Kunstler 253 &278, Peak Prosperity,  Index of best energyskeptic posts

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Book Review of  Bottleneck: Humanity’s Impending Impasse, by William R. Catton, Jr.  Reviewed by George Mobus in The Oil Drum.

In Catton’s book, Bottleneck: Humanity’s Impending Impasse, Catton doesn’t mince words: we can’t evade the worst any longer.  Civilization is going to collapse.  The main reason is not just how big the changes are, it’s the RATE of CHANGE.  We are destroying the world so rapidly across so many resources  we can neither adapt or mitigate the problems.  We’re past the point of no return.

One reason this happened is that we got too specialized in our division of labor, which has led to dehumanization and isolating us from each other.  Many see other people as instruments to be used to further our own ends.

Humans, like all animals, have a biological dictate to maximize their access to energy. For humans this meant learning to control fire, making clothing, building shelters, the invention of tools and agriculture. It culminated in the discovery of fossil fuels that allow modern humans incredible power over their environment. Catton renames a the people in developed countries who consume massive amounts of fossil fuels Homo colossus, who can use machines that do orders of magnitude more work than a human can do with muscle power. This is done by burning carbon which produces CO₂ and returns fossil carbon deposits to the atmosphere and oceans after sequestration for millions of years. It’s the rapidity with which this is happening which leads Catton to conclude that we can’t put the brakes on for this train. You can try but you won’t stop in time to avoid a crash.

Unfortunately for mankind, there are now far too many of Homo colossus in the global population. And the damage is done. NASA climatologist James Hanson has claimed that the concentration of CO₂ in the atmosphere should not be over 350 parts per million (ppm) in order to avoid calamitous climate shifts. But we are already at 400ppm and climbing.

Catton sees an impending threat from the fact that we are going to run out of this magical fuel one day.  When that happens what becomes of Homo colossus? Indeed what happens to Homo sapiens? Even though peoples in developing and underdeveloped nations don’t burn the fuels directly, they still rely on the developed world for aid produced by burning those fuels.

Catton bases his analysis on the idea of carrying capacity. Fossil fuels have artificially boosted the carrying capacity of earth for human occupancy (if you ignore the damage we’ve done to other species). We are in overshoot, the theme of his previous book. We are like the cartoon character, Wile Coyote, racing off a cliff in futile pursuit of the Roadrunner, suspended mid air until he realized his predicament; then it was too late and he would fall. When the fossil fuels are effectively used up, what will replace them? As things stand now, there simply is no realistic or viable alternative energy source that could scale up to the level needed by modern civilization in time to take over the job. Once again, it’s the rate of change that gets us.

In spite of continued pie-in-the-sky thinking by even engineers and scientist who should know better, no one has shown how real time solar energy in all of its many forms (thermal, photovoltaic, wind, even hydroelectric) will ever match the power in fossil fuels. These came from ancient photosynthesis over millions of years compressed and cooked into a convenient package over more millions of years. The scope of concentration is literally unimaginable (apparently) yet very serious people dream of capturing current solar influx and replacing fossil fuels with it. They may be serious but they are also dreamers or delusional. While in theory, the total daily influx of solar energy to the earth would provide many times over what we need to sustain our current civilization and provide development for the lesser developed nations, our systems of capture would have to cover gigantic areas of the planet. Our energy storage and distribution systems would have to be radically redesigned and rebuilt. And all of this comes just as we recognize the impacts of declining net energy from fossil fuels; those fuels being needed to subsidize the building of all that energy infrastructure.

It is this lack of inherent wisdom that will keep us, has kept us, from doing the right things to prevent the impending impasse. Catton’s ‘Prognosis for Humanity’, page 206, is alarming.

…with great reluctance and regret, I am compelled to doubt that we can confidently hope to avoid a serious “crash” as the focal human experience of the 21st century—envisioned also as our species having to pass through an ecological “bottleneck”.

This is by far the most explicit statement of what we would call doom of any author in the popular book trade. There have been many writers, especially in the blogosphere, who have expressed similar conclusions. But I have yet to see a writer of some eminence such as Catton go all out and claim that the end is near. Unfortunately, I happen to agree with him.

The question for me is: Will humanity come through this bottleneck with a gene pool competent to meet the challenges of a changed world AND have a stronger native capacity for sapience, for wisdom? Assuming some remnant of humanity does survive, that is no guarantee that our descendants will go on to evolve a better ability to make good, long-term judgments in that future world. Nor are we guaranteed that they will be able to reconstruct anything like modern technology-based society in order to re-achieve a species fitness allowing them to survive and thrive in the very long run.

I have to applaud Catton for writing so honestly about what he has concluded. Every other author of books on end-of-the-world scenarios at least offers that if we would only come to our senses… the world won’t end. William Catton does not do this. Sorry for the spoiler but you should know in advance. Thus this probably isn’t a book easily digested by everyone, even though I think everyone who believes themselves to be a critical thinker should read it.

The reviewer is an Associate Professor of Computing and Software Systems at the University of Washington Tacoma. He is currently on sabbatical leave studying biophysical economics and energy-related issues at the State University of New York, Environmental Sciences and Forestry in Syracuse NY. His blog is Question Everything at: http://questioneverything.typepad.com

Hooke, R; Martin-Duque, J.F. 2012. Land transformation by humans: A Review.  Geological Society of America.

Prognosis for the Future

Looking ahead a few decades, land suitable for agriculture will likely continue to diminish as

• urban areas expand
• soil is degraded
• fertile soil is washed down rivers and blown away 10 times faster than it is replaced (Montgomery, 2007)
• water tables decline in areas dependent on groundwater for irrigation (Gleick, 1993)
• Foreseeing a shortage of arable land, global investors are, in fact, buying huge tracts in Africa and South America (De Castro, 2011).

Despite foreseeable future technological developments, agricultural productivity is likely to decrease as

1. the supply of phosphate for fertilizer decreases (Rosmarin, 2004)
2. petroleum (used to run farm machinery and as feedstock for fertilizer) becomes more expensive and less available
3. pollution adversely affects pollinators, plant growth, and predators that control agricultural pests (Peng et al., 2004; supplemental data, Sec. H [footnote 1])
4. climate changes.

Will Earth be able to support the projected 2050 population of 8.9 billion?

Wackernagel et al. (2002) estimate that, as of 1978, the land area needed to grow crops, graze animals, provide timber, accommodate infrastructure, and absorb waste sustainably, has already exceeded Earth’s available area, and that as of 2002, we needed 20% more land than is available. If this is the case, we are in a period of overshoot.

Overshoot

Overshoot occurs when populations exceed the local carrying capacity. An environment’s carrying capacity for a given species is the number of individuals “living in a given manner, which the environment can support indefinitely” (Catton, 1980, p. 4). Only a population less than or equal to the carrying capacity is sustainable.

A sustainable population is one that (i) consumes renewable resources at a rate less than the rate at which they are renewed; (ii) consumes non-renewable resources at a rate less than the rate at which substitutes can be found; and (iii) emits pollution at a rate less than the capacity of the environment to absorb the pollutants (Daly, 1991, p. 256).

It is axiomatic that, on a finite planet, there is a limit to growth. The question is, “Are we now bumping up against that limit?”

Several observations suggest that, with our present lifestyles, we are, indeed, now living in a state of overshoot.

We struggle to supply the food needed by the present population. Groundwater tables are declining. Our way of life is based on non-renewables like fossil fuels, phosphates, and ores, accumulated over millions of years, with no clear plan for adequate substitutes once natural sources are exhausted. We discard many chemicals (e.g., CO₂, N, plastics) faster than they can be absorbed by the environment.

When the number of individuals exceeds the carrying capacity, overuse of the environment sets up forces that, after a delay, first reduce the standard of living and then eventually the population (Catton, 1980, p. 4–5). Initiation of the correction may be manifested by stagnant or negative economic growth rates, by famine and/or water shortages, by increases in disease resulting from undernourishment (Pimentel et al., 2007), and by increases in conflict. Sound familiar? Fifty-four nations with 12% of the world’s population experienced economic declines in per capita GDP from 1990 to 2001 (Meadows et al., 2004, p. xiv; World Bank, 2003, p. 64–65). Famine, disease, and conflict are frequently in the news.

Cropland

The rate of change in area of cropland and pasture has decreased in the last few decades. Projected into the future, these trends suggest a peak and then a decline in the areas of both. Let’s focus on cropland, because that is the land use for which data are most robust and the one of most concern, given our swelling population. At least 3 trends are contributing to the decline in the rate of increase in cropland:

1. Urban area is increasing, commonly at the expense of agricultural land. Between 2000 and 2030, worldwide, the loss of agricultural land to urbanization may be as much as ~15,000 km² annually (Döös, 2002).
2. There is a dearth of additional land suitable for agriculture. Of Earth’s land area, 70% to 80% is unsuitable for agriculture owing to poor soils, steep topography, or adverse climate (Fischer et al., 2000, p. 49; Ramankutty et al., 2002). About half of the rest is already in crops (Table 1), and a large fraction of the other half is presently under tropical forests that beneficially take up CO₂. Tropical-forest soil loses fertility rapidly, once cleared.
3. Some existing agricultural land has deteriorated so much that it is no longer worth cultivating. As of ca. 1990, soils on nearly 20 Mkm² of land, or ~40% of the global agricultural land area, had been degraded (Oldeman et al., 1991, p. 28). Of this, over half was so degraded that local farmers lacked the means to restore it.

Partially offsetting these trends may be increases in efficiency of farming and food distribution. Rudel et al. (2009), however, could not find correlations that supported this hypothesis.

Solutions

If we are in a state of overshoot, here are some ways to bring the human impact on Earth back to sustainability:

1. Reduce demand. Demand can be reduced by improving building insulation or mandating energy-efficient vehicles and appliances. Recycling reduces demand for primary materials. Tempering our impulse to buy things that we don’t really need or of which we will soon tire also reduces demand.

2. Develop technological solutions. Existing technology can mitigate our impact. Adoption of efficient building and farming practices limits degradation, and ecological restoration can partially reverse it (Rey Benayas et al., 2009). Technological breakthroughs are also possible. Simon (1996) argued that a larger population increases the likelihood of spawning the brain power needed to achieve such breakthroughs. But without well-fed bodies, brains don’t function well.

Our technological skills have enabled us to support an ever increasing population. They have also exacerbated some problems. Use of oil as an energy source in agriculture has increased efficiency, but at the expense of leaving us presently dependent on a non-renewable resource. Mechanical well drilling and pumping facilitate irrigation, but now ground-water tables are dropping unsustainably (Gleick, 1993). Given present usage, more than half of the U.S. High Plains aquifer will likely last for 50 to 200 years, but significant parts will be exhausted in <~25 years while others are already effectively spent (Buchanan et al., 2009). Use of bioengineered wheat in Punjab, India, and rice in Bali, Indonesia, increased crop yields, but also led to a variety of economic, pest, and health problems (Tiwana et al., 2007, p. xxii–xxiii; Lansing, 1991, p. 110–117).

3. Reduce the population. Increasing the availability of health care, education, and microfinancing, particularly for women in developing countries, reduces fertility. Reduced fertility reduces poverty, because available resources are distributed among fewer people. Couples worldwide can be urged to have only two children and to delay having them so there will be fewer people on Earth at any one time. These steps would first slow population growth and then lead to a long-term decline.

Reducing demand is a critical component of the solution, but in itself is not sufficient, given the magnitude of the problem. Technological progress, particularly in the energy field, is essential, but we also think it unwise to bet too heavily on unspecified future breakthroughs. Reducing and eventually reversing population growth needs to be a large part of the solution. Eventually, difficult decisions will have to be made about the size of an optimum population and how to achieve it.

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