The atmospheric carbon cycle

It can be seen that the great majority of carbon is cycled in the atmosphere as carbon dioxide. Thus, although the oxidation of CO provides an important sink, the process does not supply an important C02 source. It follows from the data given that the residence times of methane, carbon monoxide and carbon dioxide are 5.0 0.25 and 5.2 years, respectively. 

Atmospheric pathways of carbon compounds. Sote. CH4 released by paddy fields isconsidered biogenic 

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Approximately 1% of the atmospheric carbon cycle is maintained by methane (Ehhalt, 1974). Global background levels of CH4 are estimated at... 

Understanding heterogeneous chemistry (4) the structure of natural organic matter (2) air sources and characterization of toxics (1) speciation of toxic metals (1) smokestack emissions beyond SOx and NOx (1) chemical sources of toxicity of fine particulate matter (PM2.5) (1) environmentally persistent free radicals (1) understanding of greenhouse gases in the atmosphere (carbon cycles and sinks)... 

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