Green·house Gas ['grEn-"haus 'gas]. Any gas that absorbs infra-red radiation in the atmosphere. Greenhouse gases include water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halogenated fluorocarbons (HCFCs) , ozone (O3), perfluorinated carbons (PFCs), and hydrofluorocarbons (HFCs).

water vapor,

carbon dioxide (CO2),

methane (CH4),

nitrous oxide (N2O),

halogenated fluorocarbons (HCFCs) ,

ozone (O3),

perfluorinated carbons (PFCs), and

hydrofluorocarbons (HFCs).