Spatial and Temporal Variability of PM2.5 due to Wildfire Outbreaks in California

Wildfires contribute to the concentration of particulate matter in the air causing hazardous air quality, impacting human health and environment, and influencing the climate system. Being exposed to particulate matter less than 2.5 micrometers in diameter (PM_2.5) can cause adverse health effects such as cardiovascular and respiratory diseases. In recent years, California wildfire activity has greatly increased, this is why we are focusing on California for this study. During the wildfire outbreaks, air quality monitors indicate particulate matter surpass the federal daily 24-hr average regulation. The aim of this project was to investigate the correlation between temporal and spatial variability of PM_2.5 with wildfires. Meteorological conditions such as wind, precipitation, and air temperature were explored to examine their influence on wildfires and harmful air quality. A daily distributed PM_2.5 product developed using combination of remote sensing and observations of PM_2.5 was used for this study. The study is performed for wildfire events observed in California within 2006-2016 period. Meteorological or other environmental data was obtained from the North American Land Data Assimilation Systems (NLDAS). The fire detection data were obtained from a Moderate Resolution Imaging Spectroradiometer (MODIS) derived dataset. Our results show, high exceedance probability of PM_2.5 concentration at the locations of the MODIS detections, and it correlates very well with high temperature and high wind speed at the fire locations. Assessing PM_2.5 contributions from wildfires and the influence of meteorological conditions on its variability is critical to continue understanding air pollution in California.