Emissions from ships contribute significantly to the release of aerosols into the environment and have an adverse effect on climate, marine ecosystems, and public health (Sofiev et al., 2018). The emission characteristics of ships can be assessed through studies based on engine test benches. These measurements are carried out under controlled conditions, however, only few parameters can be varied due to complexity of the setup. The transfer to real emission scenarios is challenging since there are only a few comparative studies based on the sampling of real shipping traffic. Additionally, the regulatory framework has changed considerably in recent years resulting in a change of emission profile. Our study presented here attempts to close this gap and for the first time compares the emissions of an engine test bench with the real emission patterns found on open sea. Our inclusive approach combined a land-based localized 1-cylinder ship engine (ULtrafine particles from Trans-portation – Health Assessment of Sources, ULTRHAS) and data from a multi-week ship-based measurement expedition to characterize real emission patterns in the Baltic Sea (Tracing of ship Plumes and impact to sea water, PlumeBaSe). Both setups offer unique advantages of, on the one hand, known input parameters such as fuel, engine load and dilution, and on the other hand, a consideration of the complex marine aerosol background, influencing weather conditions and more diverse engine operations. The localized ship engine was run on global (0.5 % S) or sulfur emission control area (SECA, 0.1 % S) compliant fuels. Primary emission as well as standardized and controlled aged emission aerosol was investigated. To replicate the atmospheric aging process caused by oxidation during aerosol transport, a photochemical emission aging flow tube reactor (PEAR, Ihalainen et al., 2019) simulated atmospheric aging ranging from two to seven days. During the Baltic Sea expedition, the particulate emissions from more than 50 ships, mostly cargo vessels, were remotely probed based on different sampling scenarios. Physical PM characterization was realized by operating an airship and fast working boats directly in the fresh plume of the ships. The remote monitoring on the research base ship included fast particle size spectrometers, sampling of particulate matter (PM) and the use of a single particle mass spectrometer (SPMS). Volatile and semi-volatile organic compounds present in the PM samples were thoroughly characterized using comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC-TOFMS). The engine test stand allowed the sampling of sufficient sample quantities of PM to deeply characterize them chemically by GC×GC-TOFMS. Reproducible particle size distributions and individual particle data could also be determined for the limited number of operation scenarios. Through the applied probing scenarios in the expedition, the chemical and physical data from many ships could be mapped, reflecting the diverse real emission situations on one of the most frequently travelled waterways. The characterization of chemical loading of individual particles via the SPMS showed distinguishable MS patterns of ships using different fuels (Rosewig et al., 2023). GC×GC-TOFMS enabled the detection of a similar chemical pattern as observed from the SECA compliant fuel. Through this approach, we facilitate a thorough examination of the chemical and physical composition of current ship emissions by linking the results of our land-based case studies to real world exposure scenarios. PlumeBaSe is supported by the German (DFG, 471841824) and Czech Science Foundation (CSF, 22-03426L=). ULTRHAS is funded under the EU’s research and innovation programme Horizon 2020 (955390).    «

Emissions from ships contribute significantly to the release of aerosols into the environment and have an adverse effect on climate, marine ecosystems, and public health (Sofiev et al., 2018). The emission characteristics of ships can be assessed through studies based on engine test benches. These measurements are carried out under controlled conditions, however, only few parameters can be varied due to complexity of the setup. The transfer to real emission scenarios is challenging since there a...    »