Methane is a powerful greenhouses gas with a 100-year global warming potential 28-36 times that of CO2. Measured over a 20-year period, that ratio grows to 84-87 times (IEA, Methane Tracker 2021).
About 60% of global methane emissions are due to human activities. The main sources of anthropogenic methane emissions are the oil and gas industries, agriculture (including fermentation, manure management, and rice cultivation), landfills, wastewater treatment, and emissions from coal mines. Fossil fuel production, distribution and use are estimated to emit over 120 million tonnes of methane annually.
Methane is the primary component of natural gas, with some emitted to the atmosphere during its production, processing, storage, transmission, distribution, and use. It is estimated (IEA, 2022) that more than 260 billion cubic metres (bcm) of natural gas is lost annually to venting, leakage, and flaring, resulting in substantial economic and environmental costs.
Coal is another important source of methane emissions. Coal mining related activities (extraction, crushing, distribution, etc.) release some of the methane trapped around and within the rock. Methane is emitted from active underground and surface mines as well as from abandoned mines and undeveloped coal seams.
The geological formation of oil can also create large methane deposits that get released during drilling and extraction. The production, refinement, transportation and storage of oil are all sources of methane emissions, as is incomplete combustion of fossil fuels. No combustion process is perfectly efficient, so when fossil fuels are used to generate electricity, heat, or power vehicles these all contribute as sources of methane emissions.
Despite methane’s short residence time, the fact that it has a much higher warming potential than CO2 and that its atmospheric volumes are continuously replenished make effective methane management a potentially important element in countries’ climate change mitigation strategies. As of today, however, there is neither a common technological approach to monitoring and recording methane emissions, nor a standard method for reporting them.