" \"tendency_of_X\" means derivative of X with respect to time. The construction \"atmosphere_moles_of_X\" means the total number of moles of X in the entire atmosphere, i.e. summed over the atmospheric column and over the entire globe. The chemical formula for xylene is C6H4C2H6. In chemistry, xylene is a generic term for a group of three isomers of dimethylbenzene. The IUPAC names for the isomers are 1,2-dimethylbenzene, 1,3-dimethylbenzene and 1,4-dimethylbenzene. Xylene is an aromatic hydrocarbon. There are standard names that refer to aromatic_compounds as a group, as well as those for individual species." . . . "tendency of atmosphere moles of xylene" . "Climate and Forecast (CF)" . .