This project will deploy the In Situ Airborne Formaldehyde (ISAF) instrument on the NOAA WP-3D aircraft during the AEROMMA field campaign, and use formaldehyde measurements to examine the emissions and fate of VOCs in urban environments. Formaldehyde (HCHO) plays a central role in atmospheric oxidation processes as both a product of VOC oxidation and a source of oxidants. AEROMMA measurement priorities include detailed VOC speciation, and HCHO is a key component of the VOC pool. This study will enhance our ability to predict air quality now and in the future as a function of increasing urbanization and rising temperatures. Chemically detailed observations during AEROMMA alongside HCHO observations will be key to interpreting future high-resolution satellite-based HCHO observations, extending the impact of the AEROMMA project well beyond the spatial and temporal scales of the field campaign. The ultimate goal is to improve our understanding of VOC oxidation and thereby improve the air quality models used in policy decisions.