Influence of ship emissions on ozone concentrations around coastal areas during summer season

The influence of ship emissions on ozone (O3) concentrations in a coastal area (CA) including Busan port, Korea was examined based on a numerical modeling approach during a high O3 episode. The analysis was performed by two sets of simulation scenarios: (1) with ship emissions (e.g., TOTAL case) and (2) without ship emissions (e.g., BASE case). A process analysis (PA) (the integrated processes rate (IPR) and integrated reaction rate (IRR) analyses) was used to evaluate the relative contributions of individual physical and chemical processes in O3 production in and around the CA (e.g., sites of Dong Sam (DS) and Dae Yeon (DY)). The model study suggested the possibility that pollutant gases emitted from the ships traversing Busan port can exert a direct impact on the O3 concentration levels in the CA. Largest impacts of ship emissions on the O3 concentrations were predicted at the coast (up to 15 ppb) and at inland locations (about 5 ppb) due to both the photochemical production of pollutant gases emitted from the ships and meteorological conditions. From the PA, the photochemical production of O3 (P(O3)) due to ship emissions in the CA was found to increase by a mean of 1.5 ppb h−1 (especially by ≥10 ppb h−1 at the DS site) during the day.