an area characterized by air with common qualities. Compare Watershed.

a body of air bounded by topography and meteorology in which a contaminant, once emitted, is contained for a reasonable period of time.

A geographic area that shares the same air.

A geographical area where local topography and meteorology limit the dispersion of pollutants away from the area.

A geographical area that shares the same air mass due to topography, meteorology and/or climate. As such, pollutants emitted into this area may interact or increase in concentration. It typically forms an analytical or management unit

The area of land over which airborne pollutants can travel to reach a particular river, lake, bay or other body of water. The Chesapeake Bay’s airshed is 570,000 square miles, stretching north to Cana [..]

A subset of air basin

An area designated by a regional council or unitary authority for the purposes of managing air quality and gazetted by the Minister for the Environment

a term denoting a geographical area of which, because of topography, meteorology, and climate, shares the same air (see Air Basins)

An area where emitted pollutants may interact or increase in concentration. The delineation of an airshed may be influenced by topographic features such as a land:water interface.