Kang Sun, Research Assistant Professor, University at Buffalo
Ammonia (NH3) and methane (CH4) have similar molecular structures and are both critical trace constituents of the Earth’s atmosphere. Ammonia is the dominant atmospheric alkaline species that neutralize sulfate and nitrate to form secondary inorganic aerosols, a significant component of PM2.5. Methane is a potent greenhouse gas and responsible for at least a quarter of the warming occurring today. Significant uncertainties exist in the state-of-the-art emission inventories for both ammonia and methane, necessitating more observations and further understanding to reconcile the conflicts between bottom-up and top-down approaches. This presentation will highlight the research efforts to quantify the concentrations and emissions of ammonia and methane over a range of spatial and temporal scales. Eddy covariance flux measurements, vehicle-based mobile measurements, and a data-driven approach to estimate emissions using satellite products from CrIS, IASI, and TROPOMI will be presented and compared with bottom-up inventories.