Organic nitrate is a major contributor to fine particular matter (PM2.5) that affects Earth’s radiative balance, visibility, and environmental and human health. Atmospheric formation pathways of this particulate organic nitrate are ill-defined, however. In the current project, data collected during past field campaigns will be synthesized and analyzed to determine particulate organic and inorganic nitrate concentrations in PM2.5. This data will be used to constrain formation mechanisms in current atmospheric chemistry models which will help guide future research, improve predictive modeling of PM2.5, and inform nitrogen budget models.
Data obtained with High-Resolution Time of Flight Aerosol Mass Spectrometers (HR-ToF-AMS) during 15 US field campaigns between 2009 and 2016 will be exploited for particulate organic and total nitrate. To test and validate mechanisms of organic and inorganic nitrate formation, temporally and spatially matched 3-D atmospheric chemistry transport (GEOS-Chem) model simulations will be performed and compared with observed concentrations. The new dataset will be made publicly available for use by other groups to guide future studies and help constrain regional and global models beyond the GEOS-Chem community. The PI will perform this work as a Postdoctoral Research Fellow at the Massachusetts Institute of Technology while engaging diverse undergraduate students in research.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
