Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

Although atmospheric particles are of crucial importance to both human health and global climate, their detailed chemistry in the atmosphere is not well characterized. In particular, once particles are formed, they are subject to atmospheric oxidative processes that may alter their composition and chemical properties. To place climate and air quality models on a firm fundamental foundation, the chemistry of these processes needs to be understood. And so, it is proposed to conduct a suite of novel laboratory experiments to provide a more complete view of the mechanisms of atmospheric aerosol oxidation and the potential impacts on the atmosphere.

Specific projects will assess: i) the rates and mechanisms by which the coloured components of aerosol (i.e. “brown carbon”) will be chemically altered in aerosol particles and clouds, ii) the role that oxidation plays in affecting the ability of particulates to act as the sites for ice cloud nucleation, iii) the formation rates of reactive oxygenated species in the particle, and iv) the rate of uptake of reactive radicals from the gas phase to the aerosol particle. This chemistry will have impacts on the composition, hygroscopicity, optical properties, and toxicity of ambient atmospheric aerosol. State of the art instrumentation will be used in this research program, in particular the use of both novel on-line and off-line mass spectrometric approaches. Along with collaborative opportunities, this will provide trainees with a background in advanced analytical methods.

The overall impact of this research program will be to further develop our fundamental understanding of how anthropogenic activities are impacting our natural environment.