Quantification of global methane sources and sinks

In a recent publication in Nature Geoscience, an international expert team including Martin Heimann of MPI-BGC recalculated global methane budgets from the past 30 years, using a combination of atmospheric measurements and results from chemical transport models, ecosystem models, climate chemistry models and inventories of anthropogenic emissions. The inferred budgets show a substantial decadal variability which can be traced to changes in the different CH4 sources and sinks. The renewed increase in global methane levels after 2006 is most probably due to increased emissions from natural wetland emissions and from fossil fuel mining, e.g. exploitation of natural gas from shale formations (natural gas fracking).
Three decades of global methane sources and sinks, Nature Geoscience, 6, 813-823, Publication