Professor, Chemistry Department
Allan Bertram received his BSc from the University of Prince Edward Island and PhD from the University of Waterloo, where he studied the freezing behaviour of polar stratospheric clouds. Following an NSERC Postdoctoral fellowship at the Massachusetts Institute of Technology, he joined the Department of Chemistry at the University of British Columbia (UBC) in 2001. He was a Tier II Canada Research Chair in Environmental and Atmospheric Chemistry from 2001-2011, and in 2012 he became a full professor at UBC. Recently he was awarded an NSERC Discovery Accelerator Supplement Award (2008-2011), the Chemical Institute of Canada Environment Division Research & Development Dima Award (2015), and the UBC Killam Faculty Research Prize (2017). He is also the former director of an interdisciplinary atmospheric aerosol program funded through the NSERC CREATE program. Currently, he serves as Co-editor of the journal Atmospheric Chemistry and Physics (2013 – present). The research in his group focuses on the chemistry and physics of atmospheric aerosols and the role these aerosols play in urban air pollution, climate change and atmospheric chemistry.
Current Group Members
Viscosity and diffusion influence the speed at which reactions take place in the atmosphere. Adrian is interested in the effect of low temperature on the viscosity and diffusion coefficients relating to aerosols. Adrian uses fluorescence microscopy to measure the diffusion coefficients of organics in aerosol samples at different temperatures.
To correctly predict the effects of atmospheric aerosol particles on cloud formation, climate, and air quality, the chemical and physical properties of aerosol particles must be accurately constrained in global atmospheric models. One such physical property is the diffusion of molecules within aerosol particles. Erin uses fluorescence microscopy to measure the diffusion of molecules in proxies for aerosol particles. The results are used to improve the equations which calculate diffusion of molecules within aerosol particles in global atmospheric models.
The freezing of supercooled water droplets in the atmosphere can be promoted by the presence of ice nucleating substances (INSs). Ice nucleation (IN) is an important process for Earth’s climates by affecting the properties of clouds, while the sources and mechanisms of IN remain uncertain. Yu’s work focuses on the role that marine biological materials play as INSs.
Secondary organic aerosols (SOA) are abundant in the troposphere. Knowledge of the diffusion rate of organics within SOA is needed to predict their impact on climate, air quality, and visibility. The temperature in the troposphere can vary by about 100 K, and as a result, measurements of diffusion in SOA at different temperatures are needed. Kris uses fluorescence microscopy to measure diffusion of organics in SOA and proxies of SOA as a function of temperature.
Ice nucleation in the natural environment usually takes place in aqueous solutions rather than pure water, however the mechanisms underlying this process at the molecular scale is still unclear. The nucleation is termed heterogeneous when it is facilitated by the presence of foreign particles or surfaces. Yi’s research utilizes Molecular Dynamics modeling to investigate possible salt effects on heterogeneous ice nucleation.
Ice particles play an important role in the atmosphere by influencing physical processes and subsequently the overall climate. Atmospheric ice particle formation is encouraged by ice nucleating particles (INPs), which provide energetically favorable conditions for ice formation of aerosol liquid droplets. There are still many questions regarding the abundance, identities, and overall climate impact of atmospheric INPs. Soleil’s research is focused on the quantification and characterization of ice nucleating particles in field samples.