Akirah Epps

This research explores the dynamics of atmospheric ammonia, (NH3​) in regions dominated by concentrated agricultural activity. By integrating satellite observations with chemical transport modeling, my research aims to characterize how NH3​ emissions influence aerosol chemistry and regional air quality.

As the leading producer of milk and dairy products in the U.S., California maintains an extensive landscape of concentrated animal feeding operations (CAFOs), primarily centered in the San Joaquin Valley. These facilities represent a dominant source of atmospheric ammonia (NH3​) emissions through animal housing, manure management, and land application. Despite its critical role in regional air quality and secondary aerosol formation, NH3​ remains difficult to quantify with high precision due to its high spatiotemporal variability. This research presents a multi-faceted approach to characterizing ammonia dynamics over California by integrating high-resolution satellite observations, chemical transport modeling, and localized dairy source data. By leveraging the Infrared Sounding Atmospheric Interferometer (IASI), we will oversample satellite observations to a 1km grid to identify emission hotspots. This integrated framework allows for a more robust assessment of how near-source ammonia influences aerosol acidity and hygroscopicity, ultimately aiming to provide a corrective layer for regional models to better represent the chemical impacts of California’s dairy industry.