In complying with the emission limits imposed in the frame of the Sulphur Emission Control Areas (SECAs), ships are currently mandated to use fuel oil with strictly limited sulphur content or use exhaust scrubbers that, in the case of open-loop operation, can discharge a significant volume of acidic seawater. At the same time, atmospheric emissions of PM, SOx, NOx, CO, BC, and ammonia from the ship exhaust stack still represent a potentially important environmental burden, both in terms of atmospherically dispersed plumes, as well as pollutants deposited and absorbed by the oceanic environment through the plume-water interface. The EMERGE project aims to quantify the effect of these interactions, both under current conditions and future mitigation regimes, on the atmospheric and oceanic environment. In the frame of the project, a coupled atmospheric-oceanic modelling framework was developed for simulating the combined emission and dispersion of air and water plumes in the wake of scrubber-equipped vessel. In the present work, a sensitivity study on the shipping emissions is presented by applying the coupled models in a baseline emissions case for the Piraeus port area, part of the Eastern Mediterranean EMERGE case study.