Methane (CH4) is an important greenhouse gas in the atmosphere. The methane emission budget has a sizeable anthropogenic contribution, which makes methane the most important non-CO2 greenhouse gas released from anthropogenic activities. Methane emissions play a key role in hydroxyl consumption, thus contributing to complex interactions central to atmospheric chemistry and climate. Reduction of CH4 emissions can provide quick and cost effective cuts in global warming, but requires a sound understanding of the different anthropogenic sources. Although the total global CH4 budget is relatively well understood, the contributions of individual sources to CH4 emissions are poorly constrained. Anthropogenic methane emissions in Austria are largely based on Tier 1 bottom-up scaling and urban emission sources are subject to significant uncertainty. In collaboration with the JRC Ispra, we propose a holistic top-down approach to constrain methane emissions on the local to urban scale based on eddy flux observations of methane along with a suite of additional chemical markers.
IAO Flux Tower in Innsbruck