Atmospheric layers are characterized by differences in chemical composition that produce variations in temperature.

The troposphere (14k jpeg) is the atmospheric layer closest to the planet and contains the largest percentage of the mass of the total atmosphere. It is characterized by the density of its air and an average vertical temperature change of 6 degrees Celsius (C) per kilometer.

Temperature and water vapor content in the troposphere decrease rapidly with altitude. Water vapor plays a major role in regulating air temperature because it absorbs solar energy and thermal radiation from the planet's surface. The troposphere contains 99 % of the water vapor in the atmosphere. Water vapor concentrations vary with latitudinal position. They are greatest above the tropics, where they may be as high as 3 %, and decrease toward the polar

While the best way of reducing acid rain is to lower emissions, much effort is being directed at tackling the symptoms of acid rain. For example, large quantities of lime are added to lakes to neutralise acid.

Table 1: Major pollutants in our air

Photochemical smog is formed on still days when the sun shines on air containing volatile organic compounds (VOCs) and oxides of nitrogen. Volatile organic compounds include hydrocarbons, as well as alcohols, aldehydes and ethers. VOCs in the air arise mainly from automotive fuels and industrial solvents. Chemical reactions driven by sunlight and involving VOCs and oxides of nitrogen form ozone - a gas harmful to humans, animals and plants.

Some topics in this essay:
Atmospheric Structure, Particles Motor, Melbourne Australian, Studies CSIRO, Protective Ozone, Air Pollution, Friedrich Schonbein, Atmosphere Earth, Day Atmosphere, Effects Carbon, acid rain, water vapor, air pollution, motor vehicles, sulfur dioxide, ultraviolet radiation, earth's surface, photochemical smog, air quality, carbon monoxide, burning fossil fuels, motor vehicles industry, particles motor vehicles, rain-water slightly acidic, radiation planet's surface,