Synopsis: This project will focus on measurements of atmospheric variability in coastal areas, using various in-situ and remote sensing sensors. Specifically, one of the objectives is to deploy sensors at fixed locations across coastal regions, as well as onboard research vessels and moving platforms, to assess spatial and temporal (diurnal and seasonal) dynamics in atmospheric traces gases (NO2 and O3) over estuarine and coastal waters, as well as across the land-ocean interface. Measurements will be performed in coastal regions characterized by different levels of atmospheric pollution, including the Chesapeake Bay estuary. Results will be compared with measurements of atmospheric nitrogen pollution performed as part of NOAA ARL (Air Resources Laboratory) field activities.