Evaluation of cruise ships emissions in the Mediterranean basin: The case of Greek ports

In this article a bottom-up methodology based on in-port ships activity has been applied to calculate exhaust pollutant values (NOx, SO2, and PM2.5) during moving/maneuvering and while hoteling for international cruise ship journeys to and from 18 ports of Greece during 2013. The estimated emissions were analyzed in terms of gas species, seasonality, and activity. In terms of the total in-port inventory for cruise shipping, NOx is dominant (2487.9 tons), followed by SO2 and PM2.5 (995.3 and 121.3tons respectively), while the total emissions of greenhouse gases (GHG) were 124,767.8tons CO2-eq (for CO2, N2O, and CH4). Emissions during hoteling corresponded to 89.2% of total, and significantly outweighed those produced during the vessels' maneuvering activities (10.8% of total). Seasonality was found to play a major role, as summer emissions and associated impacts are more profound. In almost all major ports, an extension of the tourism season to October and November has been observed, leading to increased autumn emissions. The estimated inventory indicates the necessity of measures for careful control over the emissions produced by cruise ships in port cities through effective environmental policy making.