Measurement of Physicochemical Properties of Black Carbon and Brown Carbon and the Impacts of Canada Record-Breaking Wildfires in Summer 2023

Wildfires have become more prevalent in recent years because of climate change. Meanwhile wildfires, as a major type of biomass burning, could emit a large amount of black carbon (BC) and brown carbon (BrC) to the atmosphere. Since BC and BrC play important roles in climate change, air pollution and human health issues, it is necessary to research their physicochemical properties to evaluate their impacts on urban areas. Here we present BC mass concentration and absorption coefficients measured by aethalometer (AE43), combing with the chemical constitutions acquired by GC-MS, during the record-breaking 2023 wildfire season in Canada. The back-trajectory analysis indicated that the smoke mainly came from north Quebec where the wildfires took place. We demonstrated how BC and BrC emitted by wildfires could affect urban regions after long-range transport.