Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker <i>Amundsen</i> from the <i>Polar 6</i> aircraft platform

Abstract

Abstract. Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols) campaign, the plume dispersion and gas and particle emission factors of effluents originating from the Canadian Coast Guard icebreaker Amundsen operating near Resolute Bay, NU, Canada, were investigated. The Amundsen burned distillate fuel with 1.5 wt % sulfur. Emissions were studied via plume intercepts using the Polar 6 aircraft measurements, an analytical plume dispersion model, and using the FLEXPART-WRF Lagrangian particle dispersion model. The first plume intercept by the research aircraft was carried out on 19 July 2014 during the operation of the Amundsen in the open water. The second and third plume intercepts were carried out on 20 and 21 July 2014 when the Amundsen had reached the ice edge and operated under ice-breaking conditions. Typical of Arctic marine navigation, the engine load was low compared to cruising conditions for all of the plume intercepts. The measured species included mixing ratios of CO 2 , NO x , CO, SO 2 , particle number concentration (CN), refractory black carbon (rBC), and cloud condensation nuclei (CCN). The results were compared to similar experimental studies in mid-latitudes.Plume expansion rates (γ ) were calculated using the analytical model and found to be γ = 0.75 ± 0.81, 0.93 ± 0.37, and 1.19 ± 0.39 for plumes 1, 2, and 3, respectively. These rates were smaller than prior studies conducted at mid-latitudes, likely due to polar boundary layer dynamics, including reduced turbulent mixing compared to midPublished by Copernicus Publications on behalf of the European Geosciences Union. 7900 A. A. Aliabadi et al.: Ship plume intercept using aircraft in the Arctic latitudes. All emission factors were in agreement with prior observations at low engine loads in mid-latitudes. Ice-breaking increased the NO x emission factor from EF NO x = 43.1 ± 15.2 to 71.6 ± 9.68 and 71.4 ± 4.14 g kgdiesel −1 for plumes 1, 2, and 3, likely due to changes in combustion temperatures. The CO emission factor was EF CO = 137 ± 120, 12.5 ± 3.70 and 8.13 ± 1.34 g kgdiesel −1 for plumes 1, 2, and 3. The rBC emission factor was EF rBC = 0.202 ± 0.052 and 0.202 ± 0.125 g kg-diesel −1 for plumes 1 and 2. The CN emission factor was reduced while ice-breaking from EF CN = 2.41 ± 0.47 to 0.45 ± 0.082 and 0.507 ± 0.037 × 10 16 kg-diesel −1 for plumes 1, 2, and 3. At 0.6 % supersaturation, the CCN emission factor was comparable to observations in mid-latitudes at low engine loads with EF CCN = 3.03 ± 0.933, 1.39 ± 0.319, and 0.650 ± 0.136 × 10 14 kg-diesel −1 for plumes 1, 2, and 3.

Particulate trimethylamine in the summertime Canadian high Arctic lower troposphere

“…State parameters and meteorological measurements were made using an AIMMS-20 from Aventech Research Inc. Detailed information on measurement principles and instrument calibrations are given in and Aliabadi et al (2016b). In order to provide information about the chemical composition of single aerosol particles, the ALABAMA (Aircraft- based Laser Ablation Aerosol Mass Spectrometer; Brands et al, 2011) was deployed on the Polar 6 during NETCARE 2014.…”

“…Reactive trace gases were measured via a second PTFA inlet line. Further detailed information on the inlet and sampling strategy can be found in , Willis et al (2016), Burkart et al (2017) and Aliabadi et al (2016b).…”

Monitoring of compliance with fuel sulfur content regulations through unmanned aerial vehicle (UAV) measurements of ship emissions

“…Several studies have suggested inferring FSC by monitoring ship emissions and then identifying ships with excessive FSC. According to the available literature, these approaches include optical methods (lidar; Fan et al, 2018; differential optical absorption spectroscopy (DOAS); Seyler et al, 2017;UV camera; or "sniffing" methods (Balzani Lööv et al, 2014;Beecken et al, 2014). Optical methods analyze the variation of the light properties after interaction with the exhaust plume and allow, if the local wind field is known, operators to determine the emission rate of SO 2 .…”

“…Optical methods analyze the variation of the light properties after interaction with the exhaust plume and allow, if the local wind field is known, operators to determine the emission rate of SO 2 . The simultaneous measurement of CO 2 and SO 2 emissions on a routine basis with these systems is unrealistic at the moment (Balzani Lööv et al, 2014). Thus, the amount of fuel burned at the time of measurement is unknown and has to be estimated via modeling to calculate the FSC.…”

Ship plumes in the Baltic Sea Sulphur Emission Control Area: Chemical characterization and contribution to coastal aerosol concentrations

“…Other methods include e.g. measurements on laboratory engine emissions (Anderson et al, 2015;Kasper et al, 2007;Lyyränen et al, 1999;Petzold et al, 2010) or measurements on board or following a sailing ship, intersecting the emission plume (Chen et al, 2005;Murphy et al, 2009;Petzold et al, 2008;Aliabadi et al, 2016;Lack et al, 2011). However, while these methods can provide detailed knowledge on fresh emissions from a specific ship, they do not give information about the variety of particle properties between different ships, how the plume evolves during transport 45 in the atmosphere, human exposure over land areas, and these methods can be more cost-intensive.…”