Identifying strategies to reduce diesel particulate matter levels in cities

Diesel emissions are ubiquitous around the world and adversely impacts human and environmental health. One of the primary pollutants of concern from diesel combustion are the solid particles formed as a byproduct of the combustion diesel fuel, known as diesel particulate matter. In regions where there is significant transport of goods, such as port cities, emissions from trucks, ships and trains can raise ambient levels of diesel particulate matter above health standards. We studied diesel emissions in Portland, Oregon USA, a mid-sized port city through a combination of source testing/evaluation, ambient monitoring and modeling (CALPUF) to produce a validated model of ambient diesel particulate matter. Similar work is starting in Rotterdam, Netherlands. Through our model we were able to identify policies that can be used to reduce emissions and ambient concentrations of diesel particulate matter. We collaborated with a state regulators and community groups identify mitigation strategies to model. For example, we modeled the potential effect of electrification of trucks and the use of cleaner diesel construction equipment. In addition, we were able, through modelling, to explore the impact of shipping distribution centers, an emerging and growing source of diesel emissions within cities in an era of on-line shopping. Validated modeling can improve understanding of the drivers of elevated levels of diesel particulate level as well as identify potential mitigation strategies.

Keywords: Air pollution, diesel emissions, diesel particulate matter, air pollution monitoring, air pollution modeling