- Greenhouse gas: carbon dioxide, methane, and other gases whose effect is
to inhibit the radiation into space of longer-wavelength heat from
the surface of the earth.
- Gross or higher calorific value: heat released in
combustion of a unit quantity of fuel, including latent heat of
vaporisation of water in products of combustion (contrast NCV).
See table of gross calorific
values of assorted fuels