Chemical Compounds in the Atmosphere

T. E. Graedel, Chemical Compounds in the Atmosphere, Academic Press, Inc., New York, 1978. 

Graedel, T. E. (1978). "Chemical Compounds in the Atmosphere." Academic Press, New York. 

Graedel TE. 1978. Chemical compounds in the atmosphere. New York, NY Academic Press, 256. 

As Chapter 10 discusses in detail, chemical compounds in the atmosphere are partitioned between the gas and particle phases (Pankow, 1987 Bidleman, 1988), and the phase in which a chemical exists in the atmosphere can significantly influence its dominant tropospheric removal process(es) and lifetime (Bidleman, 1988 Atkinson, 1996). Gas/particle partitioning has been conventionally described by the Junge-Pankow adsorption model that depends on the liquid-phase (or sub-cooled liquid-phase) vapor pressure, Pu at the ambient atmospheric temperature, the surface area of the particles per unit volume of air, 9, and the nature of the particles and of the chemical being adsorbed (Pankow, 1987 Bidleman, 1988). The fraction of the chemical present in the particle phase, ( ), depends on these parameters through an equation of the form (Pankow, 1987 Bidleman, 1988) ... 

Numerous observations of the content of chemical compounds in the atmosphere over different territories showed that there is undoubted evidence for their movements over large distances. Among the key moments of such studies the following results should be mentioned (Matthies and Scheringer, 2001 Kravtsov, 2002) ... 

Chemical-transport models (CTMs) simulate the formation, transport, and destruction of chemical compounds in the atmosphere. These models can be directly coupled to the general circulation models... 

The oxidizing properties of the troposphere have a strong influence on the lifetime of chemical compounds in the atmosphere, and hence on the probability for a molecule to reach the middle atmosphere. Most hydrocarbons, for example, including hydrogenated halocarbons, are efficiently destroyed by the OH radical in the troposphere before they can penetrate into the stratosphere. Compounds that are not oxidized in the troposphere (e.g., chlorofluorocarbons) or weakly oxidized (e.g., methane) reach the stratosphere more easily. 

Atmospheric chemistry deals with chemical compounds in the atmosphere, their distribution, origin, chemical transformation into other compounds, and finally, their removal from the atmospheric domain. These substances may occur as gases, liquids, or solids. The composition of the atmosphere is dominated by the gases nitrogen and oxygen in proportions that have been found invariable in time and space at altitudes up to 100 km. All other components are minor ones with many of them occurring only in traces. Atmospheric chemistry thus deals primarily with trace substances. 

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