A case study into the measurement of ship emissions from plume intercepts of the NOAA ship Miller Freeman

摘要: Abstract. Emissions factors (EFs) for gas and sub-micron particle-phase species were measured in intercepted plumes as a function of vessel speed from an underway research vessel, the NOAA ship Miller Freeman, operating medium-speed diesel engine on low-sulfur marine oil (fuel sulfur content ~0.1% by weight). The fuel use conforms to MARPOL limit within emission control areas set take effect 2015 California-specific limits 2014. For many species, EFs determined using multiple measurement methodologies, allowing assessment how well different techniques agree. total PM (PM1) was dominated particulate black carbon (BC) organic matter (POM), with average POM / BC ratio 1.3. Consideration ratios observed here literature studies suggests that laboratory in-stack methods may overestimate primary relative those emitted plumes. Comparison four indicates careful attention must be paid instrument limitations biases when assessing EFBC. Particulate sulfate (SO42−) extremely small particles Freeman inefficient cloud condensation nuclei (CCN), even at high super saturations, consistent very overall particle sizes. All methodologies consistently demonstrate mass basis) PM1 mass, decreased slowed. Particle number approximately constant across change, shift towards smaller being slower speeds. gas-phase CO formaldehyde (HCHO) both increased slowed, while NOx SO2 constant.