Modelling of Biogenic Volatile Organic Compounds Emissions Using a Detailed Vegetation Inventory Over a Southern Italy Region

Abstract

Biogenic Volatile Organic Compounds (BVOC) play a key role in ozone-forming reactions and are precursors of secondary organic aerosols that absorb and scatter the atmospheric radiation, affect precipitations by acting as cloud condensation nuclei and increase PM concentrations affecting thus the human health. Therefore, it is important to develop models that can accurately estimate such emissions. BVOC emissions show wide variability depending on the distributions of plant species, their emission potentials and seasonal behavior. This work presents further developments of Plant-Specific Emission Model (PSEM) and its application over Campania region (Southern Italy) considering a detailed recognition of tree species, natural vegetation, and agricultural land performed at a very high spatial resolution (200 m). Its BVOC emissions were compared with those provided by Model of Emissions of Gases and Aerosol from Nature (MEGAN, v2.04) evidencing significant differences, particularly for isoprene. Such emissions were further used to feed a Chemical Transport Model (CTM) applied over the Vesuvius area, where vertical profiles of BVOC concentrations were measured by tethered balloon soundings. The comparison between the observed and predicted BVOC concentrations evidenced the capability of the developed model to estimate the biogenic emissions and highlighted the relevance of an accurate inventory of the vegetation.