Global warming potential compares the time-integrated radiative forcing of equal-mass emission pulses of a greenhouse gas and carbon dioxide, over a stated time horizon . It is not an instantaneous temperature ratio, and its numerical value depends on the horizon and included chemical and climatic responses.
For a gas pulse with unchanged greenhouse gas radiative efficiency and decay , its integrated forcing through is proportional to . Comparing two such lifetimes at fixed carbon-dioxide reference gives the ratio of these two factors. A fractional lifetime increase is not generally the same fractional GWP increase at finite .
A global warming potential compares equal-mass pulses. If is the greenhouse gas radiative efficiency per ppb, an emitted mass produces a mixing-ratio increment inversely proportional to molar mass . For two gases with exponential pulse removal, their GWP ratio at horizon is . The common carbon-dioxide reference integral cancels. Comparing only the per-ppb coefficients would instead compare unequal emitted masses.
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Global warming potential (GWP) is a measure used to compare the ability of different greenhouse gases to trap heat in the atmosphere over a specific time period, relative to carbon dioxide (CO₂). It provides a common unit to assess the impact of various gases on global warming. Key points about GWP include: 1. **Time Frame**: GWP is typically calculated over a 100-year period, although 20-year and 500-year timeframes are also used for certain analyses.