Global shipping releases significant amounts of pollutants such as SO2 and PM2.5, which has led to a gradual tightening of regulations in the recent past. In order to reduce emissions and improve air quality, the International Maritime Organization (IMO) has progressively reduced the sulphur content in fuels to a global level of 0.5 % and 0.1 % in Sulphur Emission Control Areas (SECA) such as the Baltic Sea. Ships sailing in the Baltic Sea are only allowed to use low-sulphur fuels or exhaust gas after treatment systems. Sophisticated measuring systems are required to monitor compliance with these regulations at sea and in coastal waters. Here we present an approach for remote detection and characterization of particulate matter from ship exhaust plumes by shore-based measurements using single particle mass spectrometry (SPMS). Our study reports the results of a field campaign conducted in the port of Rostock, Germany, at 1-3 km distance from passing ships. Other studies have shown the high sensitivity of SPMS for iron and other transition metals (V/Fe/Ni) in single particles in the size range of 0.2 - 2.5 μm (Passig et al. 2020). Based on laser desorption ionization (LDI) and resonance-enhanced multiphoton ionization (REMPI) using both a KrF excimer laser (λ = 248 nm) and CO2 laser (λ = 10.6 μm), particles from the combustion of heavy fuel oil (HFO) and other marine fuels such as marine gas oil (MGO) are analysed (Anders et al. 2023). Due to the high sensitivity of SPMS to particles from ship exhaust gases, analyses can be carried out from distances of up to several kilometres, with monitoring stations located at land or on dedicated vessels (Rosewig et al. 2023). Utilizing standard particle counters (SMPS + CPC), rapid changes in particle number concentration and size distribution indicating possible ship exhaust plumes were observed. To qualitatively characterize the chemical signatures of ambient particles (0.2–2.5 μm), single-particle mass spectrometry (SPMS) was applied. The method’s high sensitivity and selectivity to transition metals and polycyclic aromatic hydrocarbons (PAH) in individual particles made it possible to distinguish between different marine fuels even against the urban background aerosol, Figure 1. Based on automated pattern recognition, a real-time analysis is feasible (Wang 2024). With this field study we show that the principle of single aerosol particle measurement in combination with standard physical measurement methods such as the condensation particle counter (CPC) and the scanning mobility particle sizer (SMPS) can be a powerful method for remote detection, monitoring and characterization of ship exhaust particles. This research was funded by the Federal Ministry for Economic Affairs and Climate Action by the project SAARUS (grant number 03SX483D) and by dtec.bw – Digitalization and Technology Research Center of the Bundeswehr (projects “LUKAS” and “MORE”). dtec.bw is funded by the European Union – NextGenerationEU.    «

Global shipping releases significant amounts of pollutants such as SO2 and PM2.5, which has led to a gradual tightening of regulations in the recent past. In order to reduce emissions and improve air quality, the International Maritime Organization (IMO) has progressively reduced the sulphur content in fuels to a global level of 0.5 % and 0.1 % in Sulphur Emission Control Areas (SECA) such as the Baltic Sea. Ships sailing in the Baltic Sea are only allowed to use low-sulphur fuels or exhaust gas...    »