Atmospheric Pollution Answers

Sources include vehicle exhaust, factories and power plants, burning wood or fossil fuels, construction dust, agricultural chemicals, wildfires, and volcanic eruptions.

A possible long-term effect is chronic respiratory disease, such as asthma or COPD, and an increased risk of heart disease or lung cancer.

Primary pollutants are emitted directly from sources, such as soot, carbon monoxide, and sulfur dioxide. Secondary pollutants form in the atmosphere through chemical reactions involving primary pollutants, such as ground-level ozone and acid rain. Secondary pollutants are often more harmful because they can be highly reactive, although either type can be dangerous.

The troposphere contains the breathable air and weather that support life. The stratosphere's ozone layer absorbs harmful ultraviolet radiation, and the thermosphere absorbs much high-energy solar radiation and helps protect Earth. The troposphere is likely the most important for life because organisms depend directly on its air, water vapor, and moderate conditions.

Naturally occurring components of air can be pollutants when they are present in unusually high concentrations or in the wrong location and cause harm to human health, other organisms, or the environment.