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humanity_and_the_environment.docxThe Industrial Revolution has empowered mankind to dominate nature; it also made man dependent on technology and natural resources. We have it in our power to create a new world and destroy it at the same time. We are forced to confront the dilemma of economic and technological progress and environmental and ecological adversity.
God forbid that we should give out a dream of our own imagination for a pattern of the world. ~ Francis Bacon, 1626
I know of no safe responsibility of the ultimate powers of the society but the people themselves; and if we think them not enlightened enough to exercise their discretion, the remedy is not to take it from them, but to inform their discretion. ~ Thomas Jefferson, 1820.
Early Problems
Small scaled environmental problems existed long before the Machine Age when coal burning became relevant. Early pollution came from dust, wood smoke, animal manure and other things. Odors from garbage, sewage and industries such as smelting or tanning also fouled the air.
Water pollution was one of the problems early societies faced. It was largely localized in a sewer system, but more often sewage was left in the street. Lead poisoning was another major problem. Lead was commonly used in early societies and lead poisoning was common. For instance, the upper class Romans used lead-sweetened wine and grape pulp (as a condiment). The problems were so serious that in 80 C.E.the Roman Senate had to pass a law to protect water stored during dry periods so it could be released for street and sewer cleaning.
Air Pollution
Air pollution is defined as any substance in air that could, in high enough concentration, harm human, animals, vegetation, or material. Pollutants may include almost any natural or artificial composition of matter capable of being airborne. They may be in the form of solid particles, liquid droplets, gases, or in combination thereof.
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Beijing Smog 2005 |
Air Pollution -- New York City |
Generally, they fall into two main groups:
1. those emitted directly from identifiable sources
2. those produced in the air
Pollution produced in the air is caused by interaction between two or more primary pollutants, or by reaction with normal atmospheric constituents, with or without photo activation. Exclusive of pollen, fog, and dust, which are of natural origin, about 100 contaminants have been identified and fall into the following categories: solids, sulfur compounds, volatile organic chemicals, nitrogen compounds, oxygen compounds, halogen compounds, radioactive compounds, and odors.
It is evident that, the increased emission of harmful substances to the atmosphere has caused damage to the environment, human health, and quality of life. Air pollution makes people sick -- it causes breathing problems and promotes cancer -- and it harms plants, animals, and the ecosystems in which they live. Some air pollutants return to earth in the form of acid rain and snow, which corrode statues and buildings, damage crops and forests, and make lakes and streams unsuitable for fish and other plant and animal life.
Pollution is changing the earth's atmosphere so that it lets in more harmful radiation from the sun. At the same time, our polluted atmosphere is becoming a better insulator, preventing heat from escaping back into space and leading to a rise in global average temperatures. Scientists predict that the temperature increase, referred to as global warming, will affect world food supply, alter sea level, make weather more extreme, and increase the spread of tropical disease.
Acid Rain
Acid rain is precipitation which has been rendered (made) acidic by airborne pollutants. It is a type of air pollution that is formed when oxides of sulfur and nitrogen combine with atmospheric moisture to yield sulfuric and nitric acids, which may then be carried long distances from a source before they are deposited by rain. This pollution may also take the form of snow, fog, or a dry form of precipitation. The major cause of acid rain is the industrial emissions. Studies released by the U.S. government in the early 1980s, strongly implicated industries as the main source of acid rain in Eastern United States and Canada.
Acid rain has been blamed for many environmental damages, including eroding structures, injuring crops and forests, and threatening or depleting life in freshwater lakes. Originated during the Industrial Revolution, the problem of acid rain has been growing ever since. The severity of its effects has long been recognized in local settings, exemplified by the spells of acid smog in heavily industrialized areas. The widespread destructiveness of acid rain, however, has become more evident only in recent decades. In 1984, for example, environmental reports indicated that almost half the trees in Germany's Black Forest had been damaged by acid rain. The Northeastern United States and Eastern Canada have also been particularly affected by this form of pollution.
Global Warming
The Earth's climate, which has been relatively stable during the past 10,000 years is now changing. The Earth's surface temperature this century is as warm or warmer than any other century during the past 600 years; the Earth's surface temperature has increased by about one degree Fahrenheit over the last century; and the last few decades have been the hottest this century.
Although there is broad agreement that human activity, particularly the burning of fossil fuels, has reached a degree of influencing climate, there is no consensus view over how much and how fast the climate will warm. Scientists warn that elevated global temperatures could result in coastal flooding and the shifting of major climatic zones and may have serious implications for agricultural productivity.
Since 1850 there has been a mean rise in global temperature of approximately 1 Celsius degree (approximately 1.8 Fahrenheit degrees) and a 28 percent rise in carbon dioxide levels. While most scientists link this temperature rise to the increase in carbon dioxide levels, other scientists argue that this temperature rise could just be part of a natural fluctuation; such fluctuations have been recorded for tens of thousands of years and operate in short-term as well as long-term cycles. The potential consequences of global warming are so great that many of the world's top scientists have urged immediate action and have called for international cooperation on the problem.
Climate models project that the global mean surface temperature could increase another 1.5 to 6.5 oF by 2100: a rate significantly faster than observed changes over the last 10,000 years. Sea level is projected to increase by another 15 - 95 cm by 2100. While the incidence of extreme temperature events, floods, droughts, fires and pest outbreaks is expected to increase in some regions, it is unclear whether there will be changes in the frequency and intensity of tropical storms, cyclones, and tornadoes.
In summary, human-induced climate change is an important new stress, particularly on ecological and socioeconomic systems that are already affected by pollution, increasing resource demands, and non-sustainable management practices; most ecological and socioeconomic systems are sensitive to both the magnitude and rate of climate change; successful adaptation to climate change depends upon technological advances, institutional arrangements, availability of financing and information exchange; and developing countries are more vulnerable to climate change than developed countries.
The Greenhouse Effect
It is understandable that some greenhouse gases occur naturally in the atmosphere, while others result from human activities. Naturally occurring greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, and ozone.
Global Warming is an increase in the earth's temperature due to the use of fossil fuels and certain industrial and agricultural processes leading to a buildup of "greenhouse gases" (mainly carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, and water vapor) in the atmosphere. Since 1896 it has been known that these gases reduce the escape of the earth's infrared radiation into space and thus function to maintain the earth's relatively warm temperature. This is called the greenhouse effect.
Our human activities, however, add to the levels of most of these naturally occurring gases: Carbon dioxide is released to the atmosphere when solid waste, fossil fuels (oil, natural gas, and coal), and wood and wood products are burned. Methane is emitted during the production and transport of coal, natural gas, and oil. The atmospheric concentration of carbon dioxide has increased by about 30% since the Industrial Revolution in England around the 1750s because of the combustion of fossil fuels and changes in land- use practices.
What Are Emissions Inventories?
We track the gases that we release into the atmosphere in emission inventories. An emission inventory is an accounting of the amount of air pollutants discharged into the atmosphere.
It is generally characterized by the following factors:
· chemical or physical identity of the pollutants included
· geographic area covered
· institutional entities covered
· time period over which emissions are estimated
· types of activities that cause emissions
