Overview
The climate implications of increased natural gas production and use, particularly substitution of coal by natural gas in the power sector has been hotly debated since 2011.Because natural gas combustion is associated with half the carbon dioxide (CO2) emissions of coal in the electric power sector, it is often assumed that a switch to natural gas power will result in lowered greenhouse gas emissions. However, this assumption does not account for methane emissions associated with producing natural gas and bringing that natural gas to market.The past several years have seen major changes both in our understanding of the importance of reducing methane emissions as a climate mitigation measure, and the significance of natural gas and petroleum systems as a source of atmospheric methane. Here, we review the current literature to provide the most up-to-date calculations for the climate impact and magnitude of methane emissions from modern natural gas and oil development.