Emissions of ammonia in the UK, mostly from agriculture, are an increasingly important source of air pollution, specifically PM_2.5. There are no direct controls on ammonia sources and emissions are challenging to quantify. In this presentation, I will talk about work conducted in my group to quantify UK ammonia emissions using satellite observations and the GEOS-Chem chemical transport model and to evaluate bottom-up estimates of ammonia emissions from the national emissions inventory. We find spatial consistency between top-down and bottom-up estimates, but the bottom-up inventory may underestimate emissions by ~40% and misses a seasonal summer peak in emissions in regions in the UK dominated by dairy cattle farming. This has implications for our ability to model PM_2.5 and to constrain other PM_2.5 precursor emissions due to the complex relationship between secondary inorganic aerosol components. Our results also suggest that the UK may be out of compliance with Gothenburg protocol ammonia emissions targets.

Bio: Eloise is an Associate Professor in the Department of Geography at UCL. She obtained her PhD from Daniel Jacob’s research group at Harvard on a Fulbright scholarship. She is a recipient of an ERC Starting grant to address uncertainties in chemistry in the upper troposphere using satellite observations, aircraft and the GEOS-Chem model. Eloise also leads the Atmospheric Composition and Air Quality research group at UCL that investigates the effects of humans on atmospheric composition at local, regional and global scales.