Reconciling the global methane budget

There is still a gap between our bottom-up accounting of methane emissions and top-down measurement of methane concentrations in the atmosphere. If we add all methane emissions estimated through data inventories and models, the estimate of global methane concentrations is larger than the growth in methane concentrations. Isotope signatures suggest that the majority of the recent increase in atmospheric methane might be of biogenic origin. This highlights the need for better accounting and reporting of methane emissions and further research on the fate of methane in the atmosphere. The project will look at methane sources and sinks, at agricultural and wetland emissions, as well as fugitive emissions from fossil fuel infrastructure, including the breakdown of methane in the biosphere, to refine our understanding of the global methane budget.

Richard is Professor and Director of the Primary Industries Climate Challenges Centre (www.piccc.org.au), a joint research initiative between the University of Melbourne and Agriculture Victoria. He is a science advisor to the Australian, New Zealand and UK governments, and the UN FAO and European Union, on climate change adaptation, mitigation and policy development in agriculture.