Ground-level ozone
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Ground-level ozone, also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere, with an average concentration of 20–30 parts per billion by volume, with close to 100 p
Seasonal average vertical columns of tropospheric ozone in Dobson units over the period 1979 to 2000. In June to August, photochemical ozone production causes very high concentrations over the East Coast of the US and China.
Particulate matter
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Particulate matter or particulates are microscopic particles of solid or liquid matter suspended in the air. The combination of particulates and air is called an aerosol. Sources of particulate matter
PM2.5 and PM10 compared with a human hair in a graphic from the Environmental Protection Agency
Excavator (a type of heavy equipment commonly used at construction sites and roadworks) demolishing the remnants of the pre-war Postal Train 0880Station (Dworzec Pocztowy) at Jerozolimskie Avenue, Poland
Horizon and layers of the atmosphere as seen from NASA Earth Observatory: troposphere (darkest), tropopause (brown), stratosphere (gray), mesosphere, thermosphere, and exosphere (blues). Colors are due to the dominant gases and particles in each layer.
Air pollution measurement station in Emden, Germany