Characteristics and sources of submicron aerosol and trace gases in the Port of Busan, Korea

Coastal urban areas of Busan are exposed to pollution sources from port activities such as ship traffic, internal vehicular traffic, and cargo handling equipment, which pose harm to human and environmental health. Emission from port related activities potentially contribute to the degradation of local air quality. To characterize the air quality in the Port of Busan, seasonal monitoring of submicron aerosol particles and gaseous pollutants was performed from February November 2020. Chemical compositions of the non-refractory submicron aerosol (NR-PM1) was measured by means of an Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS). Trace gases (NO, NO2, SO2, O3, CO, and CO2) and volatile organic compounds (VOCs) were analyzed using air quality measurement system (AQMS) and selected ion flow tube mass spectrometry (SIFT-MS), respectively. NR-PM1 was dominated by organic aerosols (48%), followed by sulfate (26%), nitrate (13%) and ammonium (11%), and chloride (1%). Positive matrix factorization analysis was then conducted on the high-resolution organic mass spectral data set. Three OA components in summer season were identified, including a hydrocarbon-like (HOA), semi-volatile oxygenated organic aerosol (SV-OOA) and low-volatility oxygenated organic aerosol (LV-OOA) components. The influence of the meteorological conditions (namely atmospheric stability and wind direction) was first evaluated, and the most critical conditions for pollutants dispersion were identified. Port of Busan area was responsible for the source of pollutants over the surrounding urban area with sea breeze circulations in summer that transported pollutants downwind into neighboring cities. This study described the measurements obtained on atmospheric meteorology and dynamics, emissions of gases and fine particles, sources and concentrations of VOCs, photochemistry, ambient particulate matter, aerosol radiative properties, and port area plume characteristics.