Table of Contents
- Population and the Future
- Resource Depletion
- Nature & Animals
- Other Effects
- Stopping Population Growth
- End Notes
Population and the Future
The world faces a number of serious threats in the next century that could spell disaster on an unprecedented scale. The vastness of this scale is due to the shear number of people on planet earth, and will thus result in a disproportionately large capacity for death and suffering. By one estimate the number of political deaths in the twentieth century was a staggering 262 million1. With the current (2013) world population at 7.1 billion2, all it would take is a 4% death rate from catastrophe to exceed that number. I believe this to be a distinct possibility.
Each of the potential threats to the future has its own specific cause. However, in addition to putting a greater number of people at risk, population growth exacerbates every one of these causes. I will discuss each of these in brief below, but first, let us consider the history of population growth. When historical world population is visualized graphically, the image is astounding3. From the dawn of humanity, world population grew slowly until about the mid-1700’s, where it reached a level of about 800 million. Since that time, which roughly coincides with the beginning of the industrial revolution, population has exploded nearly tenfold.
What is the future of population growth? The U.N. 2010 population projections list three possible scenarios, corresponding to low, medium, and high growth4. The high growth scenario predicts that population will continue to grow linearly, reaching a staggering value of 16 billion by 2100. The low growth scenario predicts that population growth will magically and suddenly start to slow, doing an-about face by 2040, with population actually falling thereafter. My guess is that neither of these is correct. What is most likely to happen is that population will continue to grow, as predicted by the high growth scenario, until the threats facing the world are exacerbated to the point that they precipitate a crisis. This crisis will then cause an abrupt and very unpleasant drop in world population.
Many of the world’s developed populations are actually in decline, but since world population is still growing, it is clear that growth in developing countries more than compensates for this loss. This disparity of growth rates is in some ways good, since per capita resource consumption in developing countries is much lower than in developed countries. However, this does not absolve population growth from culpability. There are plenty of threats to our future that are still being exacerbated by growth of developing nations, and the economies in many of these nations, such as China and India, are growing rapidly, along with their per capita resource consumption.
With the exponential growth of world population has come a corresponding growth in resource consumption. The propensity for economic advancement to accelerate this consumption rate beyond simple population growth is fortunately tempered somewhat by efficiencies gained through technological progress. Nonetheless, the world will face a number of severe resource shortages in the coming decades. Technological innovations may alleviate some of these shortages, but not all, and some of these technologies also will greatly exacerbate environmental problems.
The most celebrated resource shortage is that of crude oil from traditional sources. By some estimates the discovery of traditional oil reserves peaked in the world around 1970. Production from these sources most like has already peaked5. Meanwhile, population growth and economic advancement, especially in Asia, will continue to accelerate the demand for these fuels. Fortunately, the world has staved off great economic disruptions by a variety of means, including efficiency gains and discovery of alternative fossil fuel sources, such as vast natural gas reserves, coal, and non-traditional oil sources such as shale and tar sands.
These alternative sources may well be able to satisfy world demand for fossil fuels at least for the remainder of the century, but at tremendous environment cost. There are potentially vast reserves of natural gas in offshore methane hydrates. However, these hydrates must be harvested with a very high degree of efficiency, as release of methane, an extremely potent greenhouse gas, into the atmosphere would greatly exacerbate global warming6. The environmental impact of coal mining and use are well known. Fracking of oil shale7 and bulk harvesting of tar sands8 are expected to have serious local environmental impact. Also, for each unit of energy that these sources of oil provide, much more CO2 is released into the atmosphere due to the very high energy costs of extracting these fuels, thus accelerating the affects of global warming.
Fresh water is another resource that faces severe shortages in the future. These shortages will obviously be regional, but many areas, including low-income nations, will be extremely vulnerable to water scarcity9. Even areas in developed nations face threats. Many groundwater levels, including the level of the famous Ogallala Aquifer in the mid-west US, have dropped continuously during the twentieth century and continue to drop10. In some areas, such as southern Florida, levels have dropped so much that the aquifers face saltwater intrusion, which would render them useless11. An obvious solution to fresh water shortage is distillation of salt water, but distillation requires an tremendous amount of energy, making it both very expensive and environmentally undesirable.
Another resource that is being depleted rapidly is arable land. Cities were founded near the best farmlands because that is where the first population centers formed. As modern cities expand outward to accommodate growing populations, these farmlands are paved over and are removed from the world arable stock. Climate change and other human activities cause desertification, which also eliminates arable land. This affect is most prevalent in developing nations12. Soil degradation is a similar process that degrades and reduces arable lands13. Fortunately, to date, the green revolution has helped sustain crop yields despite this trend. Genetic engineering technologies should continue to help in this regard. However, the ability for agriculture to continue to feed the world is far from certain, especially given the world’s finite supply of phosphorous.
Phosphorous is a key ingredient in artificial fertilizers, the primary reason for the green revolution. Estimates of phosphorous reserves range from a 50 to 200 year supply. However, there are no synthetic ways of creating phosphorous, and no substitutes for it in fertilizer14. Therefore, once these reserves are depleted, the advances of the green revolution will suddenly disappear, crop production will dramatically drop, and with it, the world’s food supply.
Nature & Animals
Homo sapiens is an animal that evolved on this earth like all others, and thus we require the same natural resources that all other life requires. As our population grows exponentially, so do our needs, and our continuous search for new resources, especially land, puts us into competition with the natural world. When humanity and nature are at odds, invariably nature looses.
As population expands and existing arable lands are lost or depleted, natural habitat is destroyed to create new farmland. This process is especially relevant in developing countries in the tropics, where rain forests are cleared by burning. Not only does this process release large mounts of CO2 into the atmosphere, thus accelerating global warming, but these newly cleared lands are poor for farming, and thus are quickly depleted. This creates a continuing cycle of burning and depletion. Since rainforests are among the most diverse and productive of all environments, this process produces a devastating loss of natural habitat and biological diversity. It is estimated that nearly 60% of prehistoric tropical forests are gone. Roughly 5-10% of species in these environments are lost every decade15. Rainforests are the worst-case example of a process that is unfolding all over the world, as growing human populations slowly encroach on, and destroy, natural habitats.
Feeding 7+ billion people is a daunting task, and tastes in developed countries covet large quantities of animal protein. The need to meet this demand economically has led to “factory” farming techniques that are extremely inhumane to farm animals16. The scale of this suffering is immense and largely hidden from the view of the public. As human populations continue to grow, and developing nations continue to demand a higher standard of living, the extent of these practices and the corresponding suffering can only be expected to grow, too.
Technology and regulations have helped to greatly reduce the potential threats of pollution. Indeed, modern cities are much cleaner than they were at the beginning of the industrial revolution. Nonetheless, threats from pollution still exist. One is the rapidly growing variety of new chemicals that are manufactured every year. This problem is not caused by population growth, so I will not dwell on it, but I do speculate that it contributes to our ever-increasing cancer rates17. Developing countries are not fortunate enough to have the technology and regulations that the developed world enjoys, and thus pollution remains a threat there, and it does grow with population.
Perhaps the most vexing type of pollutants are greenhouse gases. These gases, such as CO2, are not toxic, so they are not pollutants in the traditional sense. However, human population growth, and the corresponding consumption of fossil fuels, has caused the release of so much of these gases that their shear volume in the atmosphere is altering the earth’s climate. As Bill McKibben wrote in The End of Nature, the human population, and along with it, the affects of human activities, has grown so much that there is no longer such a thing as “nature”. We affect and alter the entire planet is some way, and therefore in some way everything is now artificial18.
Rapidly growing human populations provide an experimental breeding ground for disease. Furthermore, our close proximity in many urban areas, along with the modern ability to travel to anywhere in the world within a few hours, is a disaster waiting to happen. It is well known that we are overdue for an outbreak of a new, deadly strain of influenza19. What worries me the most is the possible emergence of an altogether new virus. Imagine the havoc that would be wrought by a virus that is as deadly as a hemorrhagic fever virus, has a long incubation period, is highly contagious, and resists traditional immunology techniques like AIDS!
All of the problems listed above that are caused by population growth lead necessarily to political instability. The poverty and despair found in poor countries with high population growth rates leads to political and religious dogma, which in turn causes civil strife, terrorism, and war. The apparent correlation between poverty and population growth rates seems to lock these countries into a state of permanent degeneration. The single best possible thing that could happen to these countries would be to somehow stabilize their population growth rates, allowing them to stabilize politically, too, and therefore advance.
Stopping Population Growth
Unfortunately, there is no easy solution to the problem of population growth. One of the main reasons for this is the existence of the cycle of poverty and growth described above. Somehow, this cycle must be broken. Fortunately, it is clear that a high standard of living tends to suppress population growth, so if the standard of living in developing countries could be raised, their population growth rates would be correspondingly lowered. Unfortunately, a higher standard of living will accelerate the rate of global resource consumption, exacerbating the problems described above.
The one bit of good news is that residents in developing countries are aware of this cycle. There is a demand in these countries for contraception that is currently unmet20. Therefore, developed countries should make it a top policy priority to help developing countries meet this need. There should also be an emphasis on education there, to ensure that an understanding of the benefits of contraception continue to spread. The current global emphasis on free trade should continue, in order to help raise the standards of living in these countries. We can only hope that global population can be stabilized before resource depletion becomes a serious threat.
Edward O. Wilson’s book, The Future of Life, describes in great detail the threats that humanity faces in the coming decades21. Everyone should read this book in order to know what their children and grandchildren will be facing. As Wilson writes, “For every person in the world to reach the present U.S. levels of consumption with existing technology would require four more planet earths”22. We had better get control of human population growth now, before all of our standards of living are reduced to far below their current levels, or worse, the world faces a crisis whose scale is unprecedented in history.
- “20th Century Democide”, University of Hawaii, URL=<http://www.hawaii.edu/powerkills/20TH.HTM>.
- “U.S. and World Population Clock”, United States Census Bureau, URL=<http://www.census.gov/popclock/>.
- See, for example, “Population Numbers, Projections, Graphs and Data”, SUSPS, URL=<http://www.susps.org/overview/numbers.html>.
- “World population”, Wikipedia, URL=<http://en.wikipedia.org/wiki/World_population>.
- Kunstler, J.H., The Long Emergency, Grove Press, New York, 2005.
- Lefebvre, Ben, “Critics Warn of Environmental Hazards in Extracting Methane Hydrate”, The Wall Street Journal, July 28, 2013, URL=<http://online.wsj.com/article/SB10001424127887323664204578610370550437906.html>.
- “Environmental impact of hydraulic fracturing in the United States”, Wikipedia, URL=<http://en.wikipedia.org/wiki/Environmental_impact_of_hydraulic_fracturing_in_the_United_States>.
- Dyer, Simon, “Environmental Impacts of Oil Sands Development in Alberta”, The Oil Drum, September 22, 2009, URL=<http://www.resilience.org/stories/2009-09-22/environmental-impacts-oil-sands-development-alberta>.
- “Human Appropriation of the World’s Fresh Water Supply”, The University of Michigan, January 4, 2006, URL=<http://www.globalchange.umich.edu/globalchange2/current/lectures/freshwater_supply/freshwater.html>.
- “Ogallala Aquifer”, Wikipedia, URL=<http://en.wikipedia.org/wiki/Ogallala_Aquifer>.
- Paquet, Anna, “Biscayne Aquifer – Saltwater Intrusion”, University of Florida, URL=<http://iml.jou.ufl.edu/projects/spring04/paquet/saltwaterintrusion.html>.
- “Desertification”, Wikipedia, URL=<http://en.wikipedia.org/wiki/Desertification>.
- “Soil retrogression and degradation”, Wikipedia, URL=<http://en.wikipedia.org/wiki/Soil_retrogression_and_degradation>.
- “Peak phosphorus”, Wikipedia, URL=<http://en.wikipedia.org/wiki/Peak_phosphorus>.
- “Facts About Rainforests”, The Nature Conservancy, October 6, 2011, URL=<http://www.nature.org/ourinitiatives/urgentissues/rainforests/rainforests-facts.xml>.
- This is well documented in Singer, Peter, Animal Liberation, Harper Collins, New York, 1975.
- Barron, Jon, “Growth of Cancer”, The Baseline of Health Foundation, February 21, 2011, URL=<http://www.jonbarron.org/article/growth-cancer>.
- McKibben, Bill, The End of Nature, Random House, New York, 1989.
- Patterson, Michael M., “The Coming Influenza Pandemic: Lessons From the Past for the Future”, J Am Osteopath Assoc, Vol. 105 No. 11 (November 1, 2005), pg. 498-500, URL=<http://www.jaoa.org/content/105/11/498.full>.
- “Family Planning Strategy Overview”, Bill & Melinda Gates Foundation, URL=<http://www.gatesfoundation.org/What-We-Do/Global-Development/Family-Planning>.
- Wilson, Edward, O., The Future of Life, Vintage Books, New York, 2002.
- Ibid, pg. 23.