chapter 19 air pollution

Aerosols

The tiny particles or droplets suspended in the atmosphere that can affect climate and human health

Air Pollutants

Substances in the air that can harm humans, other organisms, or the environment

Natural Pollutants

Air pollutants that come from natural sources, like volcanic eruptions, wildfires, or dust storms

Anthropogenic Pollutants

Pollutants produced by human activity, such as car emissions or industrial smoke

Troposphere

The lowest layer of the atmosphere, where weather occurs and most air pollution is found

Stratosphere

The atmospheric layer above the troposphere; contains the ozone layer that protects Earth from UV radiation

Hydroxyl Radical

A reactive molecule in the atmosphere that helps break down pollutants and greenhouse gases

Industrial Smog

Air pollution resulting from burning coal and fossil fuels, producing smoke mixed with fog

Photochemical Fog

Pollution caused when sunlight reacts with vehicle emissions, forming smog with ozone and other compounds

Temperature Inversion

A weather condition where warm air traps cooler air near the ground, preventing pollutants from dispersing

Primary Pollutants

Pollutants directly emitted from sources like cars, factories, or volcanoes

Secondary Pollutants

Pollutants that form in the atmosphere when primary pollutants react chemically, like ozone (O3)

Ozone (O3)

A gas composed of three oxygen atoms; protects against UV in the stratosphere but can be a pollutant at ground level

Chlorofluorocarbons (CFCs)

Human-made chemicals once used in refrigerants and aerosols that deplete stratospheric ozone

pH

A scale (0–14) measuring how acidic or basic a substance is; lower pH = more acidic

Acid Precipitation

Rain, snow, or fog with pH lower than 5.6, caused by sulfur dioxide (SO2) and nitrogen oxides (NOx) in the atmosphere

Acute Exposure

Short-term exposure to a pollutant that can cause immediate health effects

Chronic Exposure

Long-term exposure to a pollutant, which can cause gradual health effects over time

Carcinogenic Pollutants

Pollutants capable of causing cancer, such as benzene or asbestos

Clean Air Act of 1970

U.S. federal law designed to regulate air emissions from stationary and mobile sources and protect public health and the environment