Impact of ship emissions at a high receptor point in the port of Naples

The influence of in-port ship emissions of gases and particulate matter concentrations was studied in the port of Naples, the third port of Italy. The CO, NO, NO2, NOX, O3, SO2, PM10, and PM2.5 concentrations were continuously measured in May–June 2021 at a height of about 20 m from ground level to better monitor the plumes released by ship funnels. AIS data were used to obtain detailed calendars of ship activities. The impact of ship emissions in hotelling conditions was studied by splitting the port area into radial sectors, with the receptor point at the centre, grouping all docks belonging to the same sector and generating patterns of the conditional bivariate probability function. The results show the important contribution of passenger ships to NOX and SO2 concentrations at the receptor point and downwind urban area and their limited impact on PM10 and PM2.5. For PM10 and PM2.5, the results show a significant contribution of other sources external to the port and a possible contribution of commercial ships