Information on How People Affect the Environment

Throughout recorded history, man's advancements greatly improved the quality and ease of life. The Industrial Revolution, for instance, lessened physical burdens and produced more products, machines and previously unheard-of luxuries than ever before. Those life-changing advancements, however, also left an indelible impact on the environment, which continues to be stressed by greed, waste and carelessness.

Historical Perspectives

• Although man had an immediate impact on his environment, it did not globally manifest itself into a problem until the onset of the Industrial Revolution around 1750. It was then that man's disregard for his environment negatively impacted it because of his greed. By the 1960s that impact caused concerned scientists to investigate the dangers to the earth's ozone layer. They ultimately identified a hole in that layer above the Antarctic in 1982 and another one over the Arctic in 1988. In 1970 the United States government became sufficiently alarmed about the dangers to the environment that it formed the Environmental Protection Agency (EPA). Four years later the Save Drinking Water Act was passed, and by 1982 the EPA had created a superfund of money that it set aside to clean up harmful waste sites throughout the country.

Environmental Pollution

• DDT was introduced after World War II as the most effective pesticide of the day. After it washed into the soil and migrated into streams and rivers where plants and animals absorbed it with disastrous results, however, it quickly became a landmark pollutant that was banned from further use. Plants and animals died at alarming rates from the ingestion of DDT even after it was banned. The chemical's residuals left behind in the soil continue to plague us today. The environment stays stressed through man's dumping of pesticides, herbicides, waste products and innumerable amounts of harmful products.

Deforestation and Desertification

• The National Geographic Society (environment.nationalgeographic.com) estimates that approximately 30 percent of the earth's surface is covered by forests. It claims that massive deforestation clears areas the size of Panama every year and that at that rate all rain forests will have disappeared within the next 100 years. Large logging corporations harvest trees for a never-ceasing demand for wood, while farmers "slash and burn" forests for their cultivation needs. National Geographic researchers estimate that 70 percent of land animals and plants will die when their forest habitats are gone. They believe that lost forest canopies will then let the sun bake and dry the soil and allow the water to return more quickly to the atmosphere. The critical role of absorbing greenhouse gases will also be lost when the trees are gone. At its worst, deforestation will lead to desertification, with a final destruction of the productive soil.

Climate Changes

• The combustion of coal, gas and oil over the past two centuries has accumulated large amounts of carbon dioxide in the earth's atmosphere. Carbon dioxide absorbs the sun's heat and is necessary to maintain habitable temperatures on earth. An excess of it, however, called the "enhanced greenhouse effect," increases the surface temperature of the earth and causes dramatic environmental changes if it is not checked in time. A rise of only 5.4 degrees Fahrenheit in the earth's average annual temperature will dry up the planet's prairies sufficiently to make them unsuitable for agriculture, according to abheritage.ca. It will melt enough of the polar ice caps to increase the oceans' volumes to flood the world's sea coasts by several feet of water. NOAA (National Oceanic and Atmospheric Administration) and NASA (National Air and Space Administration) have charted the earth's average temperature increase over the last 100 years to be already 1.2 to 1.4 degrees Fahrenheit.

Species Endangerment

• Man's contribution to species extinction far exceeds the rate of historical extinction caused by natural phenomena, with the notable exceptions of the mass extinctions at the end of the Paleozoic and Mesozoic eras. Over-hunting and over-fishing for food and trophies endangers wildlife on every continent to the point of forcing many species into extinction. An unbalance between predator and prey can further be exacerbated with man's interjection of foreign species to attempt an amelioration of the problem.