Population Growth, Industrialization, Technology, and the Environment

John Pottage

Human population growth was relatively slow for most of human history. Within the past 500 years, however, the advances made in the industrial, transportation, economic, medical, and agricultural revolutions have helped foster an exponential, "J-shaped" rise in human population (Southwick, Figure 15.1, p. 160). The statistics associated with this type of growth are particularly striking: "Human beings took more than 3 million years to reach a population of 1 billion people...The second billion came in only 130 years, the third billion in 30 years, the fourth billion in 15 years, the fifth billion in 12 years..." (Southwick, p. 159). As human population has grown, there has been simultaneous growth within the industrial sector. Both of these increases have greatly contributed to environmental problems, such as natural resource depletion, ecosystem destruction, and global climate change. Also linked with the increasing human population are many social problems, such as poverty and disease. These issues need to be addressed by policy makers in the near future in order to ensure the survival and sustainability of human life.

One of the major effects of the huge population increase has been the depletion of natural resources and the destruction of ecosystems. In the 1960's, theorist Paul Ehrlich predicted that, given the skyrocketing figures of human population, the amount of food produced would not grow at a fast enough rate for human survival (Professor Carr Everbach, personal communication). He predicted mass starvation and death by the year 2000 as the result of uncontrolled population growth. Clearly, this did not occur. Ehrlich did not foresee the advancements made in fertilizer and farming technologies that have enabled humans to greatly increase food production to sufficient levels.

Though Ehrlich was ultimately incorrect in his hypothesis of mass human starvation, he was correct to view the necessary increase in food production as problematic. As more and more land is needed for agricultural purposes, several natural resources are being exhausted. Furthermore, ecosystems are being systematically destroyed in order to support the growing population. The necessary minerals that give soil its fertility are constantly under threat of depletion by over-farming, though new fertilizer technology has lessened this problem somewhat. Difficulties are also occurring as some farmers search for new agricultural locations. This problem is most evident in the destruction of tropical rainforests. The large-scale clear cutting of rainforest, practiced in many parts of South America, has potentially eliminated a significant number of species that depend on the forests for survival. Humans might be able to reap benefits from these unknown species, such as treating certain diseases. Unfortunately, these benefits will remain unrealized with the elimination of large tracts of rainforest. The systematic destruction of large areas of forest can also potentially have severe climatic effects. Some scholars believe that the burning of large Australian forests by ancient homo sapiens brought about world climate shifts many thousands of years ago (NPR, 2002). It is very difficult to understand and predict the entire range of possibilities brought about by an event such as rainforest destruction. Humans would therefore be wise to proceed with caution when choosing the methods for obtaining greater agricultural production.

With the increase in population, there has also been a dramatic increase in industrial productivity. In particular, the burning of fossil fuels, such as coal and oil, have had significant negative effects on the environment. Fossil fuels, an excellent source of high energy, support a significant portion of our industrial activities, such as powering vehicles, factories, and power plants. Unfortunately, these resources are finite. Once humans have exhausted the earth of all its sources of oil and coal, we will need to find alternative sources of energy. This fact by itself is not necessarily problematic. Proponents of the "tech fix" believe that humans will always find a new solution to whatever problem is encountered. Thus, new technologies have been developed that aid our search for fossil fuels, allowing humans to uncover vast new sources of oil. Other possible "tech fixes" include discovering and perfecting new sources of energy such as nuclear power (fusion or fission), solar power, wind power, or water power.

Though the "tech fix" argument provides many possible solutions for the problem of resource depletion, industrialization has had other significant negative effects on the environment. The burning of fossil fuels has substantially increased the amount of carbon dioxide in the atmosphere (Quay, 2002). These increases in carbon dioxide have, in turn, brought about increases in global warming: heat from the sun that enters the earth's atmosphere is prevented from leaving by so-called "greenhouse gases," of which carbon dioxide is a major example. The retained heat has brought about significant increases in the temperature of the earth's global climate (Hansen, et. al, 2002). The effects of global warming have the potential to be disastrous. Polar ice caps could begin to melt, leading to an increase in the water level of the oceans, and the subsequent flooding of coastal areas. The temperature of the oceans could rise, leading to the destruction of the many forms of marine wildlife that can only survive within a restricted temperature range. The shifts in climate could also negatively impact trees and plant wildlife, as these species are unable to swiftly travel the large distances necessary to accommodate the climate change. Though these problems could be solved by human intervention, such as transportation of marine and plant wildlife to their appropriate climates, there is little evidence to suggest that humans are prepared for or willing to undertake these activities. The loss of trees to climate change would be especially problematic, as it would exacerbate the problem of global warming. One major source of carbon dioxide uptake from the atmosphere is the trees and plants that use it for photosynthesis. Elimination of a significant number of plant species would result in rising levels of carbon dioxide, and, subsequently, increased global warming.

The large increase in population has also had several negative social effects that interact with technology and the environment. The greater population has necessarily brought about greater consumption of natural resources, as more people demand food, shelter, and material goods. Such high consumption of goods is associated with increased levels of pollution (Southwick, p. 160). For example, as more people drive cars, demand for oil, as well as air pollution levels, increase. There have also been increases in poverty. Southwick points out some very sobering statistics on world conditions: "One out of five people in the world, including one out of three children under the age of five, is hungry or malnourished. One out of five people has inadequate housing...One out of three people have poor health care and not enough fuel to cook food or keep warm. One out of four adults cannot read or write. Over a billion people are seriously ill with preventable infectious diseases, including malaria, tuberculosis, schistosomiasis, trypanosomiasis, and filariasis" (Southwick, p. 160). As technology has advanced to help cope with rising population numbers, many jobs have been eliminated, particularly within the domain of unskilled or manual laborers. For example, computer operated machinery has often been the replacement for humans on assembly lines at automobile factories. This technology is necessary in order to accomodate the growing demand for automobiles world wide, yet it has simultaneously brought about the unemployment of the people who used to manually assemble the parts of a car. As a result of the increasing unemployment and poverty, cities have suffered overcrowding and homelessness. Overcrowding has also helped spread infectious diseases, as dense population conditions allow these diseases to thrive. These are just a few of the many social and environmental effects of human population increase and technological advance.

Despite the widespread negative effects of human population increase and industrial growth such as resource depletion, ecosystem destruction, global warming, and poverty increase, humans have met with many successes in solving or lessening some of these problems. "Green chemistry" practices have sought to reduce chemical pollution and provide cleaner methods of industrial production (Poliakoff, et. al, 2002). Governmental policy regarding the use of CFC's has significantly reduced the size of the ozone hole (Kerr, 2002). Finally, technological advances and education programs on birth control have begun to dramatically slow the birth rates of industrialized countries, and stem overall population growth (Wattenberg, 2003). Researchers must continue to search for new, environmentally safe methods of sustaining the burgeoning human population before these problems reach the threshold of catastrophe.


Hansen, J., Ruedy, R., Sato, M., & Lo, K. (2002). "Global Warming Continues." Science, 295, 275.

Kerr, R. A. (2002). "A Brighter Outlook for Good Ozone." Science, 297, 1623-5.

NPR Radio Broadcast, March 17, 2002. http://discover.npr.org/features/feature.jhtml?wfId=1140067

Poliakoff, M., Fitzpatrick, J. M., Farren, T. R., & Anastas, P. T. (2002). "Green Chemistry: Science and Politics of Change." Science, 297, 807-810.

Quay, P. (2002). "Ups and Downs of CO2 Uptake." Science, 298, 2344.

Southwick, C. H. (1996). "Chapter 15: Human Populations." Global Ecology in Human Perspective. Oxford University Press, 159-182.

Wattenberg, B. J. (March 8, 2003). "It Will Be a Smaller World After All." New York Times: Editorial/Op-Ed Section.

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last updated 3/31/03