What metric is used to quantify the global warming potential of a greenhouse gas relative to carbon dioxide over a specific timeframe?

The metric used to quantify the global warming potential of a greenhouse gas relative to carbon dioxide over a specific timeframe is called the Global Warming Potential (GWP). Global Warming Potential (GWP) is a relative measure of how much heat a greenhouse gas traps in the atmosphere compared to carbon dioxide (CO2). It is calculated over a specific timescale, typically 20 years, 100 years, or 500 years. The GWP of CO2 is defined as 1, and the GWPs of other greenhouse gases are expressed as multiples of the GWP of CO2. For example, methane (CH4) has a GWP of 25 over a 100-year timeframe, meaning that one kilogram of methane traps 25 times more heat than one kilogram of CO2 over 100 years. The GWP depends on several factors, including the gas's radiative efficiency (how effectively it absorbs infrared radiation) and its atmospheric lifetime (how long it remains in the atmosphere). Gases with high radiative efficiency and long atmospheric lifetimes have higher GWPs. GWPs are used to compare the climate impacts of different greenhouse gases and to develop policies for reducing greenhouse gas emissions. For instance, policies aimed at reducing methane emissions can have a significant impact on mitigating climate change due to methane's relatively high GWP over shorter time horizons.