Greenhouse gas (GHG)

These are gases that are responsible for creating a ‘greenhouse effect’ in the planet’s atmosphere (i.e., trapping heat from the sun in the atmosphere). The main greenhouse gases include: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), water vapour (H2O), and synthetic fluorinated gases (CFCs, HFCs, etc.).

Comment: water vapour is also a greenhouse gas. However, for the purposes of carbon accounting (for example, using the Greenhouse Gas Protocol approach), water vapour’s impact is considered indirect and not characterised as CO₂ equivalent, so it has been excluded from the above definition.

Carbon, Climate and Life Cycle Assessment

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