a dense, discolored radiation fog containing large quanities of soot, ash, and gaseous pollutants such as sulfur dioxide and carbon dioxide, responsible for human respiratory ailments. Most industrialized nations have implemented legislation to promote the use of smokeless fuel and reduce emission of toxic gases into the atmosphere.

a contraction of smoke and fog; colloquial term used for photochemical fog, which includes ozone and other contaminants; tends to be a brownish haze.

A petrochemical haze caused primarily by the reaction of hydrocarbons and NOx with sunlight.

Smog is a mixture of fog and chemical pollutants.

A combination of the words “smoke” and “fog”; it has come to mean a polluting substance that remains suspended in the air. Smog can be made up of a variety of matter, such as aerosols, ozone, car exhaust, and sulfurous compounds, and can also aggravate medical conditions such as asthma or other breathing difficulties.

mixture of aerosols and chemical pollutants in the lower atmosphere, usually found over urban areas

Traditionally, a mixture of smoke plus fog. Today, the term "smog" has the more general meaning of any anthropogenic haze. Photochemical smog involves the production, in stagnant, sunlit atmospheres, of oxidants such as O3 by the photolysis of NO2 and other substances, generally in combination with haze-causing particles.

Originally a combination of smoke and fog but now used to describe other mixtures of pollutants in the atmosphere. See industrial smog, photochemical smog.

General term for the air pollution that comes from smoke and fog.

A low-lying perceptible layer of polluted air. The word was coined to mean a noxious mixture of smoke and fog.

A mixture of gases and aerosols generated from a variety of sources. Smogs have a damaging effect on respiratory organs of people. Most smog is attributed to the exaust from automobiles and from the discharge of industrial processes.

Smog (contraction for 'smoke fog') is a fog in which smoke or other forms of atmospheric pollutant have an important part in causing the fog to thicken, and have unpleasant and dangerous physiological effects.

A commonly used term for pollution caused by complex chemical reactions involving nitrogen oxides and hydrocarbons in the presence of sunlight. Ozone is a key component of smog. Smog-forming chemicals come from a wide variety of combustion sources and are also found in products such as paints and solvents. Smog can harm human health, damage the environment, and cause poor visibility. Major smog occurrences are often linked to heavy motor vehicle traffic.

The entrapment of pollutants in still air or fog. Photochemical smog occurs in the troposphere where sunlight causes chemical reactions in a smog, one effect of which is the generation of ozone.

A mixture of pollutants, primarily ground-level ozone (product of chemical reactions in the air involving volatile organic compounds, nitrogen oxides, and sunlight). Smog can harm humans and the environment and can cause poor visibility.

Mixture of particulate matter and chemical pollutants in the lower atmosphere, usually over urban areas.

smoky fog that hangs in the atmosphere as a result of burning fossil fuels with impurities, which can originate from the exhaust pipe of your car.

An atmospheric condition in which visibility is reduced due to air pollution that contains high levels of particulates or photochemical oxidants.

Originally a mixture of smoke and fog. Now, air pollution produced by the reaction of hydrocarbons and nitrogen oxides in the presence of sunlight. It is mainly made up of ozone.

a mixture of emissions from fossil fuels, chemical vapors, and particles combined (hydrocarbons and nitrogen oxides) with sunlight and oxygen in the air. Smog is mostly made up of ozone.

A visible haze caused primarily by particulate matter and ozone.

Air pollution. This word is a combination of "Smoke" and "Fog".

a mixture of smoke and fog; a natural fog contaminated by industrial pollutants.

Literally a contraction of "smoke" and "fog"; the colloquial term used for photochemical fog, which includes ozone and numerous other contaminants. Smog is usually adds a brownish haze to the atmosphere.

A combination of smoke and other particulates, ozone, hydrocarbons, nitrogen oxides, and other chemically reactive compounds. Under certain weather conditions they may produce a murky brown haze that causes harmful health effects. The primary source of smog in California is motor vehicles.

a term that combines the words "smoke" and "fog," coined originally in Los Angeles to characterize a visible combination of smoke and fog. Photochemical smog is the result of the interaction between nitrogen oxides and hydrocarbons

Aerosol air pollution, including dispersed liquids and solids having diameters less than about 2 micrometres.

Go to Environmental Molecules Fog that has become mixed and polluted with smoke.

The term used to describe the combination of smoke and fog in the stagnant air of London; now often applied to photochemical pollution products or urban air pollution of any kind.

A fog containing fumes, or a photochemical haze caused by the action of ultraviolet radiation on hydrocarbons and NOx from automobile exhaust.

Generally considered only photochemical air pollution. Originally meant a combination of smoke and fog.

Fog that has become mixed with smoke to form a type of pollution that adversely affects human health and the environment.

Smog is air pollution mainly consisting of ozone and nitrogen oxides, which creates a visible brownish haze (particularly in cities in the summer). Smog can cause breathing problems and greatly reduces visibility in the air. Power plants and vehicles are major causes of smog. Learn more about smog from the U.S. Environmental Protection Agency.

literally, the words "smoke" and "fog" combined; the colloquial term used for photochemical fog, which includes ozone and numerous other contaminants. It tends to provide a brownish haze to the atmosphere.

A local alteration in the atmosphere caused by human activity; mainly an urban problem that is often due to pollutants produced by fuel combustion.

A mixture of pollutants, consisting principally of ground-level ozone that is produced by chemical reactions in the air involving smog-forming chemicals. A major portion of smog-forming chemicals comes from the burning of petroleum-based fuels such as gasoline.

Smog is formed in the Earth's lower atmosphere, near ground level, when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants, and other sources react chemically in the presence of sunlight. Ninety per cent of all smog found in urban areas is made up of ground-level ozone-the same chemical found in the stratosphere. In large enough quantities, ground-level ozone can cause respiratory problems in humans and other animals, and damage to plants and building materials.

Brown summer haze that intermittently forms over some cities. It is comprised of ground-level ozone (nitrogen oxides, volatile organic compounds and fine particulates).

Term applied to a fog accompanied by pollution from industrial sources. Also applied to the haze of fine particles and gases over cities.

A combination of the words "smoke" and "fog"; in Georgia we use the term to describe the pollutants most prevalent here: ground-level ozone and particle pollution.

Air pollution associated with oxidants. (See: photochemical 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. source — any place or object from which pollutants are released. A source can be a power plant, factory, dry cleaning business, gas station, or farm. Cars, trucks, and other motor vehicles are sources, and consumer products and machines used in industry can be sources too. (See also stationary sources and mobile sources).

A combination of smoke and other particulates, ozone, hydrocarbons, nitrogen oxides, and other chemically reactive compounds which, under certain conditions of weather and sunlight, may result in a murky brown haze that causes adverse health effects. Under normal operating conditions, snowmobiles do not cause smog.

A discoloured haze that is a combination of airborne particles, gases, and chemicals (ground-level ozone) that together affect our health and our natural environment.

Mixture of vapors, gases and particles that often appears as a yellowish-brown haze in the air. Smog can be created by natural processes (such as forest fires and volcanoes) or human activities (such as the burning of fossil fuels).

A noxious mixture of air pollutants: including gases and fine particles that can often be seen as a brownish-yellow or greyish-white haze. The key components are airborne particles and ground-level ozone. Particularly vulnerable are the elderly, those with existing heart or lung disease and small children. Try to avoid using your vehicle and when buying your next vehicle, make sure it is fuel-efficient and low polluting.

Smog is a portmanteau constructed from the words "smoke" and "fog," and it is used in our times to refer to heavy air pollution. Generally, smog is created when two types of pollutants (nitric oxides from engine exhaust, and volatile organic compounds from paint, pesticides and solvents) mix together under sunlight to form ozone. Not only does smog look like a hideous brown cloud looming over urban areas, it also causes serious respiratory distress, especially in children and the elderly. In an attempt to reduce smog, state governments have passed laws that define the acceptable amount of pollution that an automobile can produce, and smog tests are used to determine whether cars, trucks or SUVs are in compliance.

Air pollution, light brown colour, containing ground-level ozone, nitrogen oxides and other compounds.

a natural fog made heavier and darker by smoke and chemical fumes

A combination of smoke, ozone, hydrocarbons, nitrogen oxides, and other chemically reactive compounds which, under certain conditions of weather and sunlight, may result in a murky brown haze that causes adverse health effects. The primary source of smog in California is motor vehicles.

Air pollution caused by a mixture of smoke and fog.

A general term used to describe the irritating haze produced by photochemical reactions in the atmosphere.

Pollution formed by the interaction of pollutants and sunlight (photochemical smog), usually restricting visibility, and occasionally hazardous to health.

a mixture of air pollutants, principally ground-level ozone, produced by chemical reactions involving smog-forming chemicals. See also haze.

a mix, in the air, of smoke and chemicals with fog

A mixture of smoke and fog generally used as an equivalent of air pollution, particularly associated with oxidants.

Fog having a high pollution content.

pollution from cars and factories that mixes with the air and produces dirty air that is harmful to plants, animals, and humans..... return

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 comes 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 (weather condition in which warm air is trapped close to the ground instead of rising). 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.

a term used to describe many air pollution problems. Smog is a contraction of smoke and fog; in California, it describes the irritating stagnant haze resulting from the sun's effect on pollutants in the air

air polluted by chemicals, smoke, particles, and dust

Dirty fog produced by air pollution in cities, and often occurring beneath a temperature inversion. The action of sunlight can produce photo-chemical smog.

The visible haze that results when sunlight reacts with air pollution.

A photochemical haze caused by the action of solar ultraviolet radiation on atmosphere polluted with hydrocarbons and oxides of nitrogen.

currently used as a synonym for general air pollution; it was originally created by combining the words smoke and fog.

The irritating haze resulting from the sunâ€(tm)s effect on certain pollutants in the air, notably those from automobile exhaust. See Photochemical Process. Also a mixture of fog and smoke.

A combination of particulate matter, ground-level ozone and other chemical pollutants which can reduce visibility and have other harmful effects.