Aerosol Interactions Between The Surface And The Atmosphere

Atmospheric aerosols play a major role in regional atmospheric chemistry and air quality, while on a global scale, aerosol processes continue to represent the largest source of uncertainty related to climate change. An important aspect of understanding the role of aerosols in these areas is to document the vertical exchange of aerosols with the surface in both urban and rural landscapes since the vertical exchange represents important sources and sinks of aerosols on regional and global scales. In this dissertation, investigation of aerosol dynamics is described for three separate field studies. First, urban eddy covariance flux measurements were made from a building rooftop in Mexico City using a quadrupole aerosol mass spectrometer (Q-AMS) to determine the fluxes of aerosol species to/from the urban landscape. Second, conditional sampling of fine particles in updrafts and downdrafts was performed above a pine forest in Colorado using a thermal desorption chemical ionization mass spectrometer (TD-CIMS) to investigate the relative strengths of sources and sinks for speciated aerosol in a forest environment. Third, the aerosol and gas phase pollutant patterns, measured in Boise, ID during wintertime inversion conditions, were analyzed with respect to the daily evolution of the planetary boundary layer depth and surface meteorological conditions. This dissertation describes the methods used for each of the three studies and summarizes the analysis of the results.