CLIMATE 2

Greenhouse Gas

A gas that absorbs radiation at specific wavelengths within the spectrum of radiation (infrared radiation) emitted by the Earth's surface and by clouds, subsequently emitting infrared radiation from a level where the temperature is colder than the surface.

Carbon Dioxide (CO2)

The principal anthropogenic greenhouse gas produced by fossil fuel combustion, land-use conversion, and cement production, with a baseline Global Warming Potential (GWP) of 1 and an atmospheric concentration rising from 278,000 ppbv (pre-industrial) to 358,000 ppbv (1994).

Methane (CH4)

A greenhouse gas generated from fossil fuels, rice paddies, waste dumps, and livestock, possessing an atmospheric lifetime of 12.2 +- 3 years and a 100-year GWP of 21. 

Nitrous Oxide (N2O)

A long-lived greenhouse gas produced from agricultural fertilizers, industrial processes, and fuel combustion, possessing an atmospheric lifetime of 120 years and a 100-year GWP of 310.

CFC-12 (CCl2F2)

A synthetic chlorofluorocarbon used as liquid coolant and in foams, with an atmospheric lifetime of 102 years and a GWP of 6,200–7,100.

HCFC-22 (CHClF2)

A hydrochlorofluorocarbon used as a liquid coolant, with an atmospheric lifetime of 12.1 years and a GWP of 1,300–1,400.

Perfluoromethane (CF4)

A perfluorocarbon gas emitted during aluminum production, with an atmospheric lifetime of 50,000 years and a GWP of 6,500.

Sulphur Hexafluoride (SF6)

An inorganic fluorinated dielectric gas with an atmospheric lifetime of 3,200 years and a 100-year GWP of 23,900.

Radiative Forcing

The net change in the planetary energy balance (measured in W/m^2) caused by anthropogenic or natural drivers of climate change.