Glyoxal in the Po Valley, Italy as a tracer for tropospheric ozone and secondary organic aerosol

The Po Valley is one of the most polluted locations in Europe due to large anthropogenic emissions and frequent stagnation events. During June and July of 2012, the Madison Laser-Induced Phosphorescence instrument (Mad-LIP) measured glyoxal at the Pan-European Gas-AeroSOls-climate interaction Study (PEGASOS) ground site in San Pietro Capofiume, Italy. Glyoxal, formed via oxidation of volatile organic compounds (VOCs), has a lifetime of about two hours and is therefore a great tracer for the local tropospheric oxidative chemistry that also produces tropospheric ozone (O3). Glyoxal has also been proposed to significantly contribute to secondary organic aerosol (SOA), and other less volatile, oxidized compounds that may also contribute to SOA are formed by the same processes that form glyoxal. Data from this study will be compared to previous years at the measurement site and other field sites, both anthropogenic and biogenic in nature. Analysis will focus on glyoxal in the context of air mass source apportionment, and its role in the production of O3 and SOA.