Comparison of Biomass Burning Signatures From Controlled Laboratory Fires With Burning Events Observed in Polluted Urban Environments of Mexicali and Mexico City

A Proton Transfer Reaction Mass Spectrometer (PTR-MS) and an Aerosol Mass Spectrometer (AMS) were used to measure the gas phase VOCs and fine particle compositions, respectively, associated with biomass burning in a series of controlled laboratory biomass fire experiments during project FLAME (Missoula Fire Lab 2007) and three separate field campaigns, Mexico City 2003, 2006 and Mexicali 2005. For the laboratory fire experiments, a quantitative comparison of the biomass burning tracer species such as acetonitrile and hydrogen cyanide in the gas phase to particulate levoglucosan and the biomass burning organic aerosol (BBOA) fraction is presented as a function of fuel type. Using the relationships derived from the laboratory experiments, specific time intervals were identified during the field campaigns when biomass burning plumes were mixed into the polluted urban plumes and the relative contributions of different emission sources are evaluated.