Measurement report: Inland ship emissions and their contribution to NO_x and ultrafine particle concentrations at the Rhine

Abstract

Abstract. Emission plumes of around 4700 ship passages were detected between March 2021 and June 2022 in the Upper Rhine Valley in Worms, Germany. In combination with ship-related data recorded via the automatic identification system (AIS), the plume composition of individuals ships was analyzed, and it was possible to quantify their contribution to the overall emission load. To obtain an integral picture of inland ship emissions, nitrogen oxide (NOx = NO + NO2) and carbon dioxide (CO2) measurements in the gas phase were combined with detailed particle-phase measurements including particle number concentration (PNC), particle size distribution (PSD) from 5 nm to 10 µm, particulate matter (PM1 and PM2.5), ultrafine particle fraction (UFP, diameter < 100 nm) and aerosol black carbon (BC). One measuring station was located inside a bridge directly above the navigation channel and was especially helpful in deriving emission factors under real-world driving conditions for the fleet on the Upper Rhine. The other station was situated on a riverbank at about 40 m distance to the shipping lane and was thus representative of the exposure of people working or living close to the Rhine. Inland ships contributed 1.2 µg m−3 or 7 % on average to the local nitrogen dioxide (NO2) concentration at the bridge above the shipping lane. NOx concentrations were increased by 10.5 µg m−3 (50 %), PNC by 800 cm−3 (10 %), PM1 by 0.4 µg m−3 (4 %) and BC by 0.15 µg m−3 (15 %). On the riverbank a NOx increase of 1.6 µg m−3 (8 %) and an NO2 increase of 0.4 µg m−3 (3 %) were observed. More than 75 % of emitted particles were found in the UFP range with a geometric mean particle diameter of 52±23 nm. Calculated emission factors (25–75 percentiles) were 26–44 g kg−1 of fuel for NOx, 1.9–3.2 g kg−1 for NO2, 0.3–0.7 g kg−1 for BC, 0.9–2.3 g kg−1 for PM1 and (1–3) × 1015 kg−1 for PNC, with a large variability observed from ship to ship. Relating these values to ship-specific parameters revealed the importance of engine characteristics, i.e., vessels using old motors with low revolutions per minute (rpm) caused comparably high emission factors for both NOx and PNC. A comparison with emission regulation limits set by the Central Commission for the Navigation of the Rhine (CCNR) and the European Union (EU) showed that – within the uncertainty of our calculation method – mean energy-dependent emission factors under real-driving conditions were slightly exceeding those under controlled laboratory conditions. The results from this study underline the importance of long-term measurements with high temporal resolution to reliably estimate the contribution of inland shipping to air pollution in cities along heavy traffic waterways and to monitor a potential future emission reduction when modernizing the fleet.

Identification and detection of high NO x emitting inland ships using multi-source shore-based monitoring data

“…In terms of ship size, as shown in figure 7(b), larger vessels exhibit higher NO x emission rates compared to smaller vessels. This is because larger vessels typically feature engines with higher power to provide the necessary propulsion and maneuvering capabilities, as confirmed by Eger et al (2023).…”

“…Kurchaba et al (2023) proposed a method for detecting anomalous NO 2 emitting ship using TROPOMI satellite data and machine learning, which does not prioritize high emitters but rather focuses on deviant emitters. In recent years, there has been a growing emphasis on the NO x emissions from ships, particularly the high emitters operating on inland waterways (Eger et al 2023, Topic et al 2023. Since the establishment of the inland ECA in the Yangtze River in 2020, which imposed restrictions on the sulfur content in ship fuels, emissions of SO 2 and PM 2.5 have seen a significant reduction (Zhang et al 2022a, Anastasopolos et al 2023.…”

A Global Analysis of Emissions, Decarbonization, and Alternative Fuels in Inland Navigation—A Systematic Literature Review

“…In their study, Eger et al [37] investigated emissions from inland shipping along the Rhine River, specifically in the vicinity of Worms, Germany, offering valuable insights into real-world emissions factors and their potential impact on air quality. The research covers a comprehensive range of pollutants, including NOx, PM, PNC, UFP, PM1, and BC, utilizing peak analysis algorithms and AIS data to assess the monthly contributions of shipping to atmospheric pollution [37]. Key findings include variable emission levels influenced by wind conditions, the predominance of ultrafine particles (UFP), and the dependence of emissions on engine characteristics such as age, power, and RPM [37].…”

“…The research covers a comprehensive range of pollutants, including NOx, PM, PNC, UFP, PM1, and BC, utilizing peak analysis algorithms and AIS data to assess the monthly contributions of shipping to atmospheric pollution [37]. Key findings include variable emission levels influenced by wind conditions, the predominance of ultrafine particles (UFP), and the dependence of emissions on engine characteristics such as age, power, and RPM [37]. Moreover, the study highlights the potential for significant emission reductions through the adoption of modern engine technologies, emphasizing the importance of fleet modernization for improving air quality along heavily frequented waterways.…”

Integrating continuous pollutant measurements with time-lapse photography to evaluate inland vessel surroundings' influence on wheelhouse indoor air quality

“…Sensor-based monitoring campaigns measuring air quality within the enclosed environment of inland ship wheelhouses provide a wealth of information [1,2]. They give an insight what pollutants a ship emits [3][4][5][6][7][8][9] and how they infiltrate in the wheelhouse [10,11]. However, the absence of explicit event labels poses a significant obstacle to understanding the underlying drivers of pollution dynamics.…”