Clean Air

Air pollution

Air pollution is the presence of substances in the air that are harmful to humans, other living beings or the environment. Pollutants can be gases, like ozone or nitrogen oxides, or small particles like soot and dust. Both outdoor and indoor air can be polluted.

Atmosphere of Earth

The atmosphere of Earth consists of a layer of mixed gas that is retained by gravity, surrounding the Earth's surface. It contains variable quantities of suspended aerosols and particulates that create weather features such as clouds and hazes. The atmosphere serves as a protective buffer between the Earth's surface and outer space. It shields the surface from most meteoroids and ultraviolet solar radiation, reduces diurnal temperature variation – the temperature extremes between day and night, and keeps it warm through heat retention via the greenhouse effect. The atmosphere redistributes heat and moisture among different regions via air currents, and provides the chemical and climate conditions that allow life to exist and evolve on Earth.

clean

Adjective

1. Free of dirt, filth, or impurities (extraneous matter); not dirty, filthy, or soiled.
2. Of metal, having relatively few impurities.

Noun

1. A removal of dirt.
2. The first part of the event clean and jerk in which the weight is brought from the ground to the shoulders.

air

Symbol

1. ISO 639-3 language code for Airoran.

Noun

1. The substance constituting Earth's atmosphere: a gaseous mixture of nitrogen, oxygen, and various trace gases.
2. The substance of the atmosphere seen as an agency of freshness.