BIO 121 Chapter 13 Vocab


the layer of gases that surrounds Earth


the lowest layer of the atmosphere, air movement drives planet's weather


The second-lowest layer of Earth's atmosphere.

Ozone layer

Protective layer in atmosphere that shields earth from UV radiation.

convection circulation

less dense warm air rises and creates vertical currents- as it rises into areas of lower atmospheric pressure it expands and cools, once it cools it descends and becomes denser and replaces the rising warm air


the state of the atmosphere at a place and time as regards heat, dryness, sunshine, wind, rain, etc.


Describes typical patterns of atmospheric conditions in a location over years, decades, centuries, or millennia

temperature inversion

atmospheric condition in which warm air traps cooler air near the earth's surface

Inversion layer

the band of air in which temperature rises with altitude

Air pollutants

gases and particulate material added to the atmosphere that can affect climate or harm people or other organisms

air pollution

the release of air pollutants

Outdoor air pollution

Air pollution outside of living or working spaces, especially buildings.

primary pollutants

Pollutants released directly from a source

secondary pollutants

pollutants that are formed by the combination of primary pollutants in the atmosphere.

residence time

The amount of time a substance spends in the atmosphere

Clean Air Act

Set emission standards for cars, and limits for release of air pollutants

Carbon Monoxide

A colorless, odorless gas that occurs as a by-product of fuel combustion that may result in death in poorly ventilated areas

sulfer dioxide

Colorless gas with pungent odor. a gas produced by coal burning which increases the acidification of rain water

Nitrogen oxides

Major source is auto exhaust. Primary and secondary effects include acidification of lakes, respiratory irritation, leads to smog and ozone. Reduced using catalytic converters.

Volatile Organic Compounds (VOCs)

carbon-containing compounds that pass easily into the vapor phase

Particular matter

Composed of solid or liquid particles small enough to be suspended in the atmosphere


A heavy metal that enters the atmosphere as a particular pollutants


chemically convert or physically remove pollutants before they leave smokestacks

Criteria pollutants

pollutants judged to pose especially great threats to human health

nitrogen dioxide

a foul-smelling reddish brown gas, produced primarily by the incomplete combustion of fuel, that contributes to smog and acidic deposition.

Tropospheric ozone

a secondary pollutant created by the reaction of nitrogen oxides and volatile carbon-containing chemical in the presence of sunlight


General term for an unhealthy mixture of air pollutants that can accumulate as a result of fossil fuel combustion, generally over industrial regions or urban areas with heavy automobile traffic

Industrial smog

found in cities that burn large amounts of coal

photochemical smog

Forms when sunlight drives chemical reactions between primary pollutants and atmospheric compounds

ozone-depleting substances

human-made chemicals that destroy ozone


human-made compounds derived from simple hydrocarbons in which hydrogen atoms are replaced by halogen atoms such as chlorine, bromine, or fluorine

Chlorofluorocarbons (CFCs)

Type of halocarbons that are useful as refrigerants

Ozone hole

A thinning of stratospheric ozone that occurs over the poles during the spring

Montreal protocol

phase out of ozone depleting substances.

acid deposition

Deposition of acidic or acid-forming pollutants from the atmosphere onto Earth's surface

Acid rain

acid deposition that takes place through rain

atmospheric deposition

The wet or dry deposition on land of a wide variety of pollutants, including mercury, nitrates, organochlorines, and others.

indoor air pollution

Occur in workplaces, schools, and homes. Outweighs those from outdoor air pollution