Attempt to estimate historical methane emissions from the oil and natural gas sector

The worldwide operating petroleum industry is considered as one of the major contributors to global anthropogenic methane emissions. However, not only absolute numbers of methane emissions from oil and natural gas production and distribution vary greatly in different global inventories, also the relative contribution of the oil and the gas sector is under discussion. In different studies, the majority of methane emissions are assigned either to natural gas or to the oil sector. For the climate emission origins are of course irrelevant, however, for the climate budget of natural gas usage it is important to know which emissions are attributable to natural gas and what number is related to oil production with its associated natural gas.

Here we use the Federal Institute of Geosciences and Natural Resources’ (BGR) worldwide database on natural oil and gas production and consumption, dating back to 1900, and compare it to global bottom-up methane emission inventories. We will present and discuss several regression approaches that fit the global data reasonably well. In addition, methane emissions of country groups are compared to natural oil and gas production and consumption data. This study finds that the emission factors that relate to gas production released during oil and gas extraction likely vary over the time and across different production areas in the world.