AP Environmental Science Unit 7 - Atmospheric Pollution

AP Environmental Science Unit 7 - Atmospheric Pollution

Clean Air Act (1970)

Clean Air Act (1970)

Legislation that identified 6 criteria air pollutants that the EPA is required to set acceptable limits for, monitor, and enforce.

Sulfur Dioxide (SO2)

Air pollutant released from coal combustion that contributes to respiratory irritation, smog, and acid precipitation.

Nitrogen Oxides (NO and NO2)

Air pollutant released from combustion of fossil fuels and biomass that leads to respiratory irritation, tropospheric ozone formation, and acid precipitation.

Carbon Monoxide (CO)

Air pollutant released from incomplete combustion that is lethal to humans and contributes to the formation of tropospheric ozone.

Particulate Matter (PM)

Solid or liquid particles suspended in the air, released from fossil fuel and biomass combustion, that can cause respiratory irritation and smog.

Tropospheric Ozone (O3)

Air pollutant formed through the photochemical oxidation of nitrogen oxides, causing respiratory irritation, smog, and plant damage.

Lead (Pb)

Air pollutant released from metal plants and waste incineration that is a neurotoxicant and damages the nervous systems of humans.

Primary Air Pollutants

Pollutants emitted directly from sources such as vehicles, power plants, factories, or natural sources.

Secondary Air Pollutants

Pollutants formed through the transformation of primary pollutants in the presence of sunlight, water, and oxygen.

Photochemical Smog

Smog formed when primary pollutants, such as nitrogen oxides and volatile organic compounds, react with sunlight, leading to the formation of tropospheric ozone and other photochemical oxidants.

Thermal Inversion

Atmospheric condition where a cooler air mass becomes trapped near the Earth's surface, preventing the dispersion of air pollutants.

Acid Rain

Precipitation that has a lower pH due to the presence of nitric and sulfuric acids formed from the reaction of nitrogen oxides and sulfur dioxide with oxygen and water in the atmosphere.

Noise Pollution

Any noise at a high enough volume to cause physiological stress or hearing loss, often caused by construction, transportation, industrial activity, or domestic activity.

Urban Heat Island Effect

Phenomenon where urban areas have higher surface and air temperatures compared to surrounding suburban and rural areas due to lower albedo and less evapotranspiration.

Acid Deposition

The process by which acid rain falls onto the Earth's surface, leading to soil and water acidification and negative impacts on plants, animals, and aquatic ecosystems.

Limestone

A natural base that can neutralize acidic soil and water by reacting with hydrogen ions, moving the pH closer to neutral.

CAFE Standards

Corporate Average Fuel Economy standards that regulate the fuel efficiency of vehicles, aiming to reduce emissions of pollutants that contribute to acid rain.

Natural Sources of Air Pollutants

Sources such as lightning strikes, forest fires, combustion of biomass, and volcanic activity that release pollutants into the atmosphere.

PM10

Particulate matter with a diameter of less than 10 micrometers, including dust, pollen, ash, and mold, which can irritate the respiratory tract and cause inflammation.

PM2.5

Particulate matter with a diameter of less than 2.5 micrometers, primarily from combustion sources, that can travel deep into the lungs and cause respiratory issues.

Indoor Air Pollutants

Substances that are released into the air indoors and can have negative effects on human health.

Developing Countries

Nations that have lower levels of industrialization and economic development compared to developed countries.

Biomass Fuels

Subsistence fuels such as wood, manure, and charcoal that are commonly used for cooking and heating in developing countries.

Commercial Fuels

Fuels such as coal, oil, and natural gas that are supplied by utilities and commonly used in developed countries.

Particulate Matter (PM)

Tiny particles suspended in the air that can be harmful to human health when inhaled.

Asbestos

A long, silicate particle that was previously used in insulation and has been linked to lung cancer and asbestosis.

Carbon Monoxide (CO)

A colorless, odorless gas that is produced by incomplete combustion and can be lethal to humans in high concentrations.

Volatile Organic Compounds (VOCs)

Chemicals used in various home products that easily vaporize and can irritate the eyes, lungs, and bronchioles.

Radon Gas

A radioactive gas released by the decay of uranium that can enter homes through cracks in the foundation and is a leading cause of lung cancer.

Dust and Mold

Natural indoor air pollutants that can worsen respiratory conditions such as asthma and bronchitis.

Lead

A toxic metal that can be found in old paint and water pipes and can cause damage to the central nervous system, especially in children.

Reduction of Air Pollutants

Strategies and measures to decrease the amount of air pollutants released into the atmosphere.

Clean Air Act

Legislation that allows the Environmental Protection Agency (EPA) to set acceptable levels for air pollutants and monitor emissions from facilities.

Pollution Credits

Credits earned by companies that reduce emissions below acceptable levels, which can be sold to companies that exceed those levels.

CAFE Vehicle Standards

Standards that require vehicle manufacturers to work towards making more fuel-efficient vehicles to reduce air pollutants.

Vapor Recovery Nozzle

A nozzle used during refueling that captures hydrocarbon VOCs released from gasoline fumes, reducing air pollution.

Catalytic Converter (CC)

A device required on all vehicles after 1975 that converts harmful gases such as NOx and CO into less harmful substances.

Crushing Limestone

A method used to reduce SO2 emissions from coal power plants by mixing crushed coal with limestone before combustion.

Fluidized Bed Combustion

A combustion process that uses jets of air to increase efficiency and reduce emissions, particularly NOx.

Wet and Dry Scrubbers

Devices used to remove pollutants from emissions, with dry scrubbers targeting NOx, SOx, and VOCs, and wet scrubbers targeting PM as well.