Unit II. The Problems of Air Pollution.

“It all depends on you and me. If we see the world as a living organism of which we are a part—not the owner, nor the tenant; not even a passenger—we could have a long time ahead of us and our species might survive for its “allotted span.” It is up to us to act personally in a way that is constructive. The present frenzy of agriculture and forestry is a global ecocide as foolish as it would be to act on the notion that our brains are supreme and the cells of other organs expendable. Would we drill wells through our skins to take the blood for its nutrients?”

James Lovelock, scientist

Before you read

· Do you agree with the idea given in the quotation of this unit?

· What manifestations of air pollution do you feel every day?

· When do you think the problem of air pollution appeared?

As you read Text 1

· Which paragraphs contain the following information?

AThe first negative impact of air pollution humans got.

BThe definition of atmosphere.

CThe definitionof air pollution.

DNaturalsources of air pollution.

ENotable examples of natural air pollution.

F Man-made sources of air pollution.

Text 1. The Matter of the Problem.

The Background in Brief.

Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99.9% nitrogen, oxygen, water vapor and inert gases. Human activities can release substances into the air, some of which can cause problems for humans, plants, and animals.

Humans probably first experienced harm from air pollution when they built fires in poorly ventilated caves. Since then we have gone on to pollute more of the earth's surface. Until recently, environmental pollution problems have been local and minor because of the Earth's own ability to absorb and purify minor quantities of pollutants. The industrialization of society, the introduction of motorized vehicles, and the explosion of the population, are factors contributing toward the growing air pollution problem. At this time it is urgent that we find methods to clean up the air.

The primary air pollutants found in most urban areas are carbon monoxide, nitrogen oxides, sulfur oxides, hydrocarbons, and particulate matter (both solid and liquid). These pollutants are dispersed throughout the world's atmosphere in concentrations high enough to gradually cause serious health problems. Serious health problems can occur quickly when air pollutants are concentrated, such as when massive injections of sulfur dioxide and suspended particulate matter are emitted by a large volcanic eruption.

While man-made air pollution does present health hazards, natural sources of air pollution can be equally dangerous at times. These sources include dust picked up by wind erosion, the emission of methane by livestock, and smoke from wildfires. Volcanic eruptions are perhaps the largest single source of air pollution, natural or man-made, that humans have ever dealt with. These can produce clouds of abrasive volcanic ash and other harmful substances such as chlorine and sulfur.

Air pollution results from a variety of causes, not all of which are within human control. Dust storms in desert areas and smoke from forest fires and grass fires contribute to chemical and particulate pollution of the air. The source of pollution may be in one country but the impact of pollution may be felt elsewhere. The discovery of pesticides in Antarctica, where they have never been used, suggests the extent to which aerial transport can carry pollutants from one place to another. Probably the most important natural source of air pollution is volcanic activity, which at times pours great amounts of ash and toxic fumes into the atmosphere.

Most notably, the eruption of Indonesia’s Mount Tambora in 1815 sent such a huge amount of noxious gases and particulate matter into the atmosphere, that much solar energy was effectively blocked from reaching the earth’s surface. As a result, widespread famines were suffered worldwide in 1816. Brown and red snows were also seen in Europe, due to the presence of volcanic ash in the atmosphere. A killing frost in July of 1816 also led to massive crop failures in the northeastern United States, leading to colloquial references to 1816 as “The Year Without a Summer,” and “Eighteen Hundred And Froze To Death.”

The atmosphere is a complex, dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.

Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or damages the natural environment, into the atmosphere. Thus, air pollution can be defined as any harmful material that is present in the earth’s atmosphere. It is aggravated because of four developments: increasing traffic, growing cities, rapid economic development, and industrialization. The Industrial Revolution in Europe in the 19th century saw the beginning of air pollution as we know it today, which has gradually become a global problem.

The causes of air pollution, therefore, are many and highly varied. Some sources are natural, such as volcanism or forest fires started by lightning, while others are brought about by human activity, such as the burning of fossil fuels. While the earth does have built-in mechanisms for getting rid of air pollution, it is usually better for all living things to reduce the amount of pollutants released into the air to begin with.

Some other sources of air pollution are man-made. The burning of petroleum products is a very common cause of air pollution, especially in metropolitan areas. This pollution comes from chemical factors present when these fuels combust. When hydrocarbons such as gasoline are burned, they produce carbon dioxide and water vapor. Incomplete combustion leads to carbon monoxide also being created as a byproduct.

After you read Text 1

· Complete the following sentences according to the context:

1. The first negative impact of air pollution humans got when they ……………

2. The primary air pollutants of urban areas are dispersed ………. in …………

3. Natural sources of air pollution include ……………………………………...

4. The source of pollution may be in one country but …………………………..

5. Air pollution is the ………………….. that cause ……………………………

6. Air pollution is aggravated because of ……………………………………….

As you read Text 2

· Choose the words from the text to complete this summary of the text.

Pollution needs to be considered … and … our homes, offices, and schools, therefore it is divided into so called … and … air pollution.