Vocabulary for Grades K-5

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Acid rain -The popular term used for wet and dry acid deposition

Acidic - A substance that has a pH less than 7.0.

Aerosols - Liquid particles suspended in the air.

Air pollution - Unwanted particles, mist or gases put into the atmosphere as a result of motor vehicle exhaust, the operation of industrial facilities or other human activity.

Air Quality Index (AQI)- The index used by the EPA and ODEQ to measure pollution in the air.  The AQI uses numbers, colors and words to describe how good or bad the air is. See Chapter 3: AQI Student Handout.

Air Quality Standards - The level of pollutants prescribed by regulations that are not be exceeded during a given time in a defined area.

• Ozone One-hour standard: 0.12 ppm. To obtain this standard, the daily maximum 1-hour average concentration measured by a continuous ambi ent air monitor must not exceed 0.12 ppm more than once per year, aver aged over 3 consecutive years.

• Ozone Eight-hour standard: 0.08 ppm. To obtain this standard, the 3-year average of the fourth highest daily maximum 8-hour average of continues ambient air monitoring data over each year must not exceed 0.08 ppm.

Alternative fuels - Substitutes for traditional liquid, oil-derived motor vehicle fuels like gasoline and diesel. Includes mixtures of alcohol-based fuels with gasoline, methanol, ethanol, compressed natural gas, and others.

Alternative Fuel Vehicle (AFV) - Motor vehicles that run on fuels other than petroleum-based fuels.

Ambient air- The atmosphere surrounding a body, open air.

Atmosphere - A complex and dynamic mixture of gases surrounding the earth.  The earth’s atmosphere is composed mainly of 78% nitrogen and 21% oxygen, with the remaining 1% in various other gases.

Attainment - An area considered to have air quality as good as or better than the national ambient air quality standards as defined in the Clean Air Act. An area may be an attainment area for one pollutant and a non-attainment area for others.

Biogenic emission - Biogenic emissions are VOC emissions found principally in forests and are the largest single source of VOCs in the U.S.

Biosphere - The zone at and adjacent to the earth's surface where all life exists; all living organisms of the earth.

Carbon dioxide -  A colorless, odorless, non-poisonous gas that is a normal part of the air. Carbon dioxide, also called CO2, is exhaled by humans and animals and is absorbed by green growing things and by the sea.

Carbon monoxide (CO) - A colorless, odorless, highly poisonous gas made up of carbon and oxygen molecules formed by the incomplete combustion of carbon or carbonaceous material, including gasoline. It is a major air pollutant on the basis of weight.

Chlorofluorocarbons (CFC’s)- these chemicals and some related chemicals have been used in great quantities in industry, for refrigeration and air conditioning, and in consumer products. CFCs and their relatives, when released into the air, rise into the stratosphere, where they take part in chemical reactions which result in reduction of the stratospheric ozone layer. The 1990 Clean Air Act includes provisions for reducing releases (emissions) and eliminating production and use of these ozone-destroying chemicals.

Climate- a general description of the average temperature and rainfall conditions of a region over a period of time.

Criteria pollutants- as defined by the EPA, six air pollutants that are the most widespread and harmful. They are: particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, and lead.

Energy- the ability to do work. Forms of energy include sunlight and the chemical bonds present in fuels.

Environment - The sum of all external conditions affecting the life, development and survival of an organism.

Fossil Fuel- Oil, coal, natural gas or their by-products. Fuel that was formed in the earth in prehistoric times from remains of living-cell organisms.

Global warming - An increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the Earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years.

Greenhouse effect - The warming of the Earth's atmosphere attributed to a buildup of carbon dioxide or other gases; some scientists think that this build-up allows the sun's rays to heat the Earth, while making the infra-red radiation atmosphere opaque to infra-red radiation, thereby preventing a counterbalancing loss of heat.

Greenhouse gases -Trace gases in the atmosphere that trap heat radiated from the sun and the earth and warm the earth. These gases are carbon dioxide (CO₂), methane (CH₄), nitrous oxides (NO_x), tropospheric ozone (O₃), and water vapor (H₂O). See greenhouse effect.

Infrared light- radiation of a longer wavelength than red light. It is invisible, but can be felt as heat.

Lead (Pb)- a heavy metal that is soluble in water and can be easily absorbed in the body, where it accumulates. One of the six criteria pollutants, it was commonly used in gasoline until it was banned in the 1980s.  

Mobile source - Any non-stationary source of air pollution such as cars, trucks, motorcycles, buses, airplanes, and locomotives.

National Ambient Air Quality Standards (NAAQS)- Standards established by EPA that apply for outdoor air throughout the country.

• Primary standards set limits to protect public health, including the health of “sensitive” populations such as asthmatics, children, and the elderly.

• Secondary standards set limits to protect the public welfare, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings.

Nitrogen oxides- gases that form when nitrogen and oxygen combine, such when fossil fuels are burned at high temperatures or when lightning strikes.

Non-attainment area- Area that does not meet one or more of the National Ambient Air Quality Standards for the criteria pollutants designated in the Clean Air Act.

Ozone (0₃)- a colorless gas made of three oxygen atoms.

• Stratospheric ozone is formed when ultraviolet (UV) radiation breaks apart O₂ and is important in blocking most harmful UV radiation from reaching the surface of the Earth.

• Ground-level ozone is a pollutant, a major component of smog. It is formed when nitrogen oxides react with sunlight and volatile organic compounds. 

Particulate matter- 1. Fine liquid or solid particles such as dust, smoke, mist, fumes, or smog, found in air or emissions. 2. Very small solids suspended in water; they can vary in size, shape, density and electrical charge and can be gathered together by coagulation and flocculation.

Peat - Peat is a renewable, natural, organic material of botanical origin and commercial significance.  In industry, peat is used primarily as a filtration medium to remove toxic materials from process waste streams, pathogens from sewage effluents, and deleterious materials suspended in municipal storm-drain water.  In its dehydrated form, peat is a highly effective absorbent for fuel and oil spills on land and water.

Photosynthesis - the process of converting light energy to chemical energy and storing it in the bonds of sugar. This process occurs in plants and some algae (Kingdom Protista). Plants need only light energy, CO₂, and H₂O to make sugar.

Precipitation- any form of moisture that condenses in the air and falls to the ground as rain, snow, sleet, etc.

Primary pollutants- air pollutants that are emitted directly into the atmosphere as a by-product of fuel combustion.

Reid vapor pressure - Its a measure of the vapor pressure of a given gasoline at a temperature of 100 degrees Fahrenheit. The higher the pressure, the greater the tendency to vaporize.

Secondary pollutants- air  pollutants that are formed in the atmosphere from the chemical reactions of primary pollutants or other pollutants.

Smog- a mixture of pollutants, principally ground-level ozone, produced by chemical reactions in the air involving smog-forming chemicals. A major portion of smog-formers come from burning of petroleum-based fuels such as gasoline. Other smog-formers, volatile organic compounds, are found in products such as paints and solvents. Smog can harm health, damage the environment, and cause poor visibility. Major smog occurrences are often linked to heavy motor vehicle traffic, sunshine, high temperatures, and calm winds or temperature inversion. Smog is often worse away from the source of the smog-forming chemicals, since the chemical reactions that result in smog occur in the sky while the reacting chemicals are being blown away from their sources by winds.

State Implementation Procedures (SIPs)- a detailed description of the programs a state will use to carry out its responsibilities under the Clean Air Act. State implementation plans are collections of the regulations used by a state to reduce air pollution. The Clean Air Act requires that EPA approve each state implementation plan. Members of the public are given opportunities to participate in review and approval of SIPs.

Stationary source - A fixed-site producer of pollution, mainly power plants and other facilities using industrial combustion processes.

Stratsophere-the layer of air that extends from about 7 to 31 miles above the earth's surface. As the stratosphere rises, the temperature increases gradually to about 32^oF. Clouds rarely form in this layer.

Sulfur dioxide- one of the six criteria pollutants, formed from burning sulfur-containing compounds, such as coal and metal refining.

Troposphere- the lowest and densest part of the earth’s atmosphere, extending from the Earth’s surface to about 7 miles in altitude. It is where life resides and where most weather changes occur.

Ultraviolet light- radiation with a wavelength shorter than violet light and with more energy. It is invisible to humans, but the increased energy can result in damaged tissues.

Urban heat island - On warm summer days, the air in urban areas can be 6-8°F hotter than its surrounding areas.  The higher temperatures in urban heat islands increases air conditioning and raises pollution levels.  Causes of the "heat island effect" include dark surfaces--that absorb more heat from the sun--and less vegetation that would provide shade and cool the air.

Visible light- the part of the spectrum that can be seen by humans.

Volatile organic compounds (VOCs)- major air pollutants present in the atmosphere as vapor such as hydrocarbon fragments and evaporated organic compounds such as paint, gasoline, and cleaning solutions. They are a major component in the formation of smog.

Water cycle- Water never stops moving. Snow and rain fall to the earth from clouds. The rain and melted snow run downhill into rivers and lakes, sometimes crashing over waterfalls. Eventually the water flows into the ocean. During evaporation, the water turns from liquid into gas, and moves from oceans and lakes into the atmosphere where it forms clouds. Then the cycle begins all over again.

Water vapor- small particles of water that are suspended in the atmosphere.

Weather- the state of the atmosphere with respect to heat or cold, wetness or dryness, calm or storm, clearness or cloudiness.