greenhouse gas

/ˌgrinˈhaʊs gæs/

/ˈgrinhaʊs gæs/

Other forms: greenhouse gases; greenhouse gasses

A greenhouse gas acts like a blanket for the Earth, trapping heat by absorbing radiation and keeping our planet warm.

A gas must contribute to the greenhouse effect to be classified as a greenhouse gas. Gases like carbon dioxide, methane, and nitrous oxide allow sunlight to enter the atmosphere but prevent some heat from escaping, similar to the way a greenhouse functions. While necessary for keeping Earth warm, an excess amount of greenhouse gases in the atmosphere can contribute to climate change, affecting both local and global temperatures.

Definitions of greenhouse gas

1. noun

   a substance in the air that warms a planet by trapping heat
   synonyms: greenhouse emission

   types:

   CFC, chlorofluorocarbon

   a fluorocarbon with chlorine; formerly used as a refrigerant and as a propellant in aerosol cans

   CO2, carbon dioxide, carbonic acid gas

   a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis

   HFC, hydrofluorocarbon

   a fluorocarbon emitted as a by-product of industrial manufacturing

   PFC, perfluorocarbon

   a powerful greenhouse gas emitted during the production of aluminum

   sulfur hexafluoride, sulphur hexafluoride

   a colorless gas that is soluble in alcohol and ether; a powerful greenhouse gas widely used in the electrical utility industry

   HCFC, hydrochlorofluorocarbon

   a fluorocarbon that is replacing chlorofluorocarbon as a refrigerant and propellant in aerosol cans; considered to be somewhat less destructive to the atmosphere

   blackdamp, chokedamp

   the atmosphere in a mine following an explosion; high in carbon dioxide and incapable of supporting life

   Freon

   any one or more chlorofluorocarbons (or related compounds) that are used as an aerosol propellant, organic solvent, or refrigerant

   type of:

   gas

   a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely