Mixed Carbon Aerosol Properties in Houston, TX (TRACER-CAT): Role of chemistry in absorption, scattering, and humidification

This past summer, the DoE Atmosphere Systems Research (ASR) Tracking Aerosol Convection ExpeRiment (TRACER) intensive operation period occurred in Houston, TX. Los Alamos National Laboratory (LANL) collaborated with UC Davis on the Carbonaceous Aerosols Thrust (TRACER-CAT with the goal of characterizing absorbing aerosols in urban and industrial environments. During this campaign, we deployed a mobile laboratory with a suite of instruments recording optical, chemical, and physical properties of aerosols from the main TRACER site in La Porte, TX. In this presentation we will provide an overview of the aerosol chemical composition as measured by a Soot Particle Aerosol Mass Spectrometer (SP-AMS) and black carbon content reported by a Single Particle Soot Photometer (SP2). We relate these results to changes in black carbon absorption efficiency, single-scatter albedo, coatings, and the effect of humidification on these aerosol properties.