Methane has important implications for climate change, particularly in the near term. Two key characteristics determine the impact of different greenhouse gases on the climate: the length of time they remain in the atmosphere and their ability to absorb energy. Methane has a much shorter atmospheric lifetime than CO2 (around 12 years compared with centuries for CO2), but it is a much more potent greenhouse gas, absorbing much more energy while it exists in the atmosphere. There are various ways to combine these factors to estimate the effect on global warming; the most common is the global warming potential (GWP). This can be used to express a tonne of a greenhouse-gas emitted in CO2 equivalent terms, in order to provide a single measure of total greenhouse-gas emissions (in CO2-eq). The Intergovernmental Panel on Climate Change (IPCC) has indicated a GWP for methane between 84-87 when considering its impact over a 20-year timeframe (GWP20) and between 28-36 when considering its impact over a 100-year timeframe (GWP100). This means that one tonne of methane can be considered to be equivalent to 28 to 36 tonnes of CO2 if looking at its impact over 100 years. In addition to its climate impacts, methane also affects air quality because it is an ingredient in the formation of ground level (tropospheric) ozone, a dangerous air pollutant. 
Why focus on methane emissions from oil and gas?......It is important to tackle all sources of methane emissions arising from human activity, but there are reasons to focus on emissions from oil and gas operations. First, although emissions also come from coal and bioenergy, oil and gas operations are likely the largest source of emissions from the energy sector. Second, our analysis shows clear scope to reduce them cost-effectively. Unlike CO2, methane – the main component of natural gas – has commercial value: the additional methane captured can often be monetised directly, and this is typically easier in the oil and gas sectors than elsewhere in the energy sector. This means that emissions reductions could result in economic savings or be carried out at low cost. Our scenario projections also suggest that oil and, particularly, natural gas will play important roles in the energy system for many years to come, even under strong decarbonisation scenarios such as the IEA Sustainable Development Scenario. Gas can play an important supporting role in energy transitions by replacing more polluting fuels; it may also deliver services that are difficult to provide cost-effectively with low-carbon alternatives, such as peak winter heating, seasonal storage, or high temperature heat for industry. However, fulfilling this role requires that adverse social and environmental impacts are minimised: immediate and major reductions in methane emissions are central to this.....read on   https://www.iea.org/reports/methane-tracker-2021/methane-and-climate-change