Development of Advanced Aerosol Instrumentation

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According to the World Health Organization, outdoor and indoor air pollution was estimated to cause ~7.2 million premature deaths worldwide per year in 2016, primarily due to exposure to particulate matter (PM), which causes cardiovascular and respiratory disease, and cancers. Air pollution is the largest environmental cause of disease and premature death in the world. Air pollution is responsible for more deaths than a high-sodium diet, obesity, AIDS, tuberculosis, malaria, alcohol, tobacco, road accidents, child and maternal malnutrition, or war and all forms of violence. The Canadian Government estimates 14,400 Canadians die from the effects of air pollution each year and the annual economic cost of the effects of air pollution is ~$8 billion. Furthermore, the Intergovernmental Panel on Climate Change states that soot (carbonaceous PM) plays a major role in global climate forcing and the impacts of climate change "include alteration of ecosystems, disruption of food production and water supply, damage to infrastructure and settlements, morbidity and mortality". The negative effects of PM can be reduced through technological advancements and regulations. However, these reductions are not possible without instruments to quantify PM emissions and understand their properties. The primary focus of my research has been developing novel aerosol instruments and techniques to quantify emissions and understand the effect PM has on health and climate so that appropriate environmental policies and regulations can be developed. The goals of this Discovery Grant are to develop and use new analytical techniques in two important research areas, namely: low-cost PM sensor calibration and the climate impact of soot. i) Low-cost PM sensor calibration - Given that air pollution is a major global problem, there has been a recent explosion in the development of low-cost PM sensors. These systems are used for building ventilation (filtration) control, monitoring PM in urban areas, workplace hazard and exposure identification, and engine emissions monitoring. However, low-cost PM sensor technology is still in its infancy and sensor developers are using indirect measurement techniques to measure the mass of the particles. Thus, a system is necessary to calibrate or characterization these sensors. This proposal investigates two methods for calibrating these sensors. ii) Mixing state and optical properties of coated soot - One large source of uncertainty in climate models is due to organic material coating soot in the atmosphere. Coatings on soot create two competing effects on soot optical properties. The coating may cause a `lensing' effect due to enhanced refraction (enhancing climate warming) and/or may cause the soot to `collapse' due to surface tension (decreasing warming). This proposal uses novel instrumentation to measure and understand the magnitude of these effects and understand the relative importance of these effects in the atmosphere.