Abstract
Background: Wildfire smoke is a leading driver of acute exposure to PM2.5 in the American West and a significant contributor to chronic pollution exposure in immediately impacted and further downwind areas. Exposure to wildfire smoke is linked to acute respiratory morbidity and all-cause mortality, yet little is known about chronic effects of repeated, elevated exposures. Inclusion of wildfire smoke in air quality models for health effects research is important for improving accuracy of the overall models and understanding the specific and independent effects of wildfire smoke relative to the entire pollution mixture. However, the nature of smoke, including high spatial variability and the three-dimensional structure of smoke plumes, presents challenges for the accurate representation of wildfire smoke in health research applications. In this presentation, we will discuss exposure and health research applications that use explicit representations of wildfire smoke to improve exposure estimates. Methods:We used dispersion modeling of wildfire smoke to predict ground-level concentrations and support a deep learning ensemble model of PM2.5 over California for 2008-2017. Smoke emissions were modeled using satellite detections of wildfires and a database of emissions related to fire radiative energy. Emissions were dispersed using a fine-scale meteorological data set. We assessed the ability of the model to reproduce spatial and temporal patterns of wildfire smoke using visual satellite imagery of smoke and correlations with ground-based monitoring, respectively. Results: Our results show that the inclusion of smoke dispersion surfaces produces accurate predictions of PM2.5 concentrations in wildfire smoke conditions. Conclusions: This work highlights the importance of incorporating wildfire smoke data sources into exposure assessments, and it indicates new directions for use of wildfire smoke data in health research. The extension of our smoke modeling through the high-smoke years between 2018 and 2021 will support important additional research on wildfire smoke exposure health impacts. Keywords: Wildfire