Understanding air pollution begins with knowing what air consists of. The air is composed of approximately 78% nitrogen and 21% oxygen, plus minute amounts of several other gases: argon, carbon dioxide, neon, methane, helium, krypton, hydrogen, and xenon (Lide, 1997). The earthÆs atmosphere is composed of four layers: the troposphere, stratosphere, mesosphere, and thermosphere. The troposphere, the densest layer of atmosphere, starts at the earthÆs surface and extends upwards 5-9 miles. The troposhere is the region of virtually all weather. The stratosphere starts just above the troposphere and goes up 31 miles. This layer, which includes the ozone layer, is drier and less dense than the troposphere. The mesosphere starts just above the stratosphere and extends to 53 miles high, with temperatures falling as low as 93¦ Celsius. The thermosphere, or upper atmosphere, starts just above the mesosphere and extends to 372 miles high. Temperatures increase in conjunction with an increase in altitude and can go as high as 1,727¦ Celsius (ôEarthÆs Atmosphere,ö 1995).
The air can be polluted by primary and secondary pollutants. Primary air pollutants are emitted directly into the air from a particular source. Carbon monoxide, for example, enters the air as a byproduct of combustion. Secondary air pollutants are formed in the atmosphere as a result of chemical reactions involving primary air pollutants, as with ozone formed by photochemical smog (ôAir Pollutionö).
Since Norway is a relatively clean country, producing very little of its own pollution, the best solution for eliminating nitrogen oxides from manufacturing lies in addressing pollution problems in the countries of origin. The United Kingdom (UK) is a major contributor to NorwayÆs pollution, so an international agreement with the UK would be the most useful remedy for addressing NorwayÆs air pollution. If the UK were to significantly reduce its emissions...