Modeling and Analysis of Tropospheric Aerosol Sources, Processes, and Effects

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

This project is directed at understanding the role of ion-induced nucleation as a mechanism for new particle formation in the troposphere. This effort involves the development of a unique microphysics code that simulates a size-resolved multicomponent aerosol system via a unified collisional mechanism involving both neutral and charged particles down to molecular sizes. The model will be used to provide new analyses of existing field measurements, through case studies, sensitivity tests, and model/data intercomparisons. These studies will involve the use of air mobility spectra, which are introduced in this context for the first time. These data are useful for studying the initial stages of aerosol formation under tropospheric conditions. This work will elucidate the pathways to particle nucleation over a range of environmental conditions, and will identify mechanisms that are in accord with a variety of field measurements. We will use these results to formulate empirical relationships between nucleation rates and ambient conditions (precursor gas concentrations, background particle surface areas, local ionization rates, temperature, relative humidity, etc.).