APES Vocab 2 - Ecological Footprint

Troposphere

The lowest layer of the Earth’s atmosphere, where weather occurs and most air pollution builds; extends up to about 10-12 km.

Stratosphere

the second atmospheric layer, located above the troposphere; contains the ozone layer that absorbs harmful UV radiation.

Mesosphere

The third atmospheric layer, above the stratosphere; coldest layer, where meteors burn up

Thermosphere

the outermost atmospheric layer; very thin air, absorbs high-energy radiation, and contains the auroras

primary pollutant

A pollutant released directly into the air from a source (e.g., CO, SO₂, NOx, VOCs).

secondary pollutant

A pollutant formed in the atmosphere from chemical reactions of primary pollutants (e.g., ozone, acid rain).

air pollution

The presence of harmful substances in the air that negatively affect human health, ecosystems, or climate.

carbon dioxide (CO2)

A greenhouse gas produced naturally and by human activities like burning fossil fuels; major driver of climate change.

carbon monoxide (CO)

A colorless, odorless gas produced by incomplete combustion; dangerous because it reduces oxygen transport in blood.

mercury (Hg)

A toxic heavy metal released mainly from coal burning and waste incineration; bioaccumulates in aquatic food chains.

particulate matter (PM)

Tiny solid or liquid particles in the air (like dust, soot, smoke) that can lodge in lungs and cause respiratory illness.

volatile organic compounds (VOCs)

Carbon-based chemicals that easily evaporate into the air (e.g., gasoline vapors, paint fumes); key in forming photochemical smog.

sulfur dioxide (SO2)

A gas from burning coal/oil and volcanic eruptions; causes respiratory problems and acid rain.

sulfuric dioxide (H2SO4)

A strong acid formed when SO₂ reacts with water vapor; major component of acid rain.

nitrogen oxides (NOx)

Gases formed from high-temperature combustion (cars, power plants); contribute to smog and acid rain.

acid deposition (acid rain)

Rain, snow, or dust that has a low pH due to sulfuric and nitric acids from SO₂ and NOx emissions.

industrial smog

Grayish smog made of sulfur compounds, particulates, and water vapor; common in coal-burning cities.

photochemical smog

Brownish smog formed when sunlight reacts with NOx and VOCs, producing ozone and other secondary pollutants.

clean air act

U.S. law that regulates emissions of air pollutants and sets standards for air quality.

criteria air pollutants

Six common pollutants regulated by the EPA: CO, Pb, SO₂, NO₂, O₃ (tropospheric ozone), and PM.

ozone (O3)

A molecule of three oxygen atoms; good in the stratosphere (protects from UV), harmful in the troposphere (lung irritant, smog).

ozone layer

The stratospheric zone rich in ozone that absorbs most of the Sun’s harmful UV-B radiation.

stratospheric ozone

“Good” ozone high in the atmosphere that protects life from UV rays.

tropospheric ozone

“Bad” ozone near the ground, a secondary pollutant formed in smog that harms lungs and plants.

scrubbers

Devices installed in smokestacks that use water or chemicals to remove sulfur dioxide and other pollutants.

electrostatic precipitators

Air pollution control devices that use electrical charges to remove particulate matter from smokestack emissions.

catalytic converter

Car exhaust device that reduces NOx, CO, and VOC emissions by converting them into less harmful gases (N₂, CO₂, H₂O).

vapor recovery nozzle

Gas pump attachment that captures gasoline vapors during fueling to prevent them from escaping into the air.

municipal solid waste (MSW)

Everyday trash and garbage from homes, schools, and businesses.

open land fill

Unregulated waste dump where trash is piled up; prone to pollution, pests, and toxic leaks.

sanitary landfill

Engineered waste site designed with liners and leachate collection to reduce environmental contamination.

e-waste

Discarded electronic devices (phones, computers, TVs) that often contain toxic metals like lead and mercury.

recycling

The process of collecting, processing, and reusing materials (like paper, metals, plastics) to reduce waste and conserve resources.