Seasonal Variation of Biogenic and Anthropogenic VOCs in a Semi-Urban Area Near Sydney, Australia

摘要: Volatile organic compounds (VOCs) play a key role in the formation of ozone and secondary aerosol, two most important air pollutants Sydney, Australia. Despite their importance, there are few available VOC measurements area. In this paper, we discuss continuous GC-MS 10 selected VOCs between February (summer southern hemisphere) June (winter 2019 semi-urban area natural eucalypt forest Sydney metropolitan fringe. Combined, isoprene, methacrolein, methyl-vinyl-ketone, α-pinene, p-cymene, eucalyptol, benzene, toluene xylene tri-methylbenzene provide reasonable representation variability total biogenic (BVOC) anthropogenic (AVOC) loading Seasonal changes environmental conditions were reflected observed BVOC concentrations, with summer peak 8 ppb, dropping to approximately 0.1 ppb winter. Isoprene, its immediate oxidation products methacrolein (MACR) methyl-vinyl-ketone (MVK), dominated concentrations during early autumn, while monoterpenes comprised larger fraction Temperature solar radiation drive seasonal variation BVOCs. Observed levels MACR MVK atmosphere closely related variations temperature photosynthetically active (PAR), but chemistry meteorology may more for monoterpenes. Using nonlinear model, explains 51% PAR 38% variation. Eucalyptol monoterpene (contributing ~75%), p-cymene (20%) α-pinene (5%) also present. AVOCs maintain an average concentration ~0.4 slight decrease autumn–winter. The low AVOC indicate relatively small influence, generally occurring when (rare) northerly winds transport emissions measurement site. site is influenced by domestic, commercial vehicle emissions. Our can be explained as listed NSW inventory thereby act independent validation inventory. We conclude that atmospheric composition seasons variable consider formulating pollution control policies over given influence sources summer, autumn