Abstract for presentation at 14th IUAPPA World Congress

Over the past decade, numerous studies, mostly in North America and Europe, have shown that predicting and mitigating tropospheric ozone formation is a complex process involving many variables, the most significant of which are the two chief precursors, VOC’s and NO_x. Literature has shown that typically two thirds of these two precursors arise from vehicular and biogenic (BVOC) emissions. Yet, South African (SA) emission inventories traditionally focus attention almost exclusively on industrial emissions.
Vegetation emissions currently utilise an outdated land use/cover file together with a plant species database that includes less than 10% of the SA plant species, contains mostly USA and European emission factors, and does not take into consideration the local adaptation of SA plants to climatic conditions. Similarly, acquiring sufficient vehicular traffic data to enable accurate emission estimates in SA is equally problematic, but essential in terms of their impact on ozone formation.
Remote sensing is increasingly being utilised to complete these knowledge gaps. Emission inventories were updated using remote sensing and recursive simplex optimisation iterative modelling studies. Highlights of these results and photochemical modelling results will be presented.