Analyzing Satellite Data and Surface-Based Measurements for Dust Events in Central California

The San Joaquin Valley in California experiences some of the worst air quality conditions in the United States, resulting in high levels of particulate matter (PM2.5 and PM10). Particulate matter is expected to increase over the next few decades due to more frequent wildfires and dust events, which will result in more negative impacts on human health, air quality, and visibility. Satellite imagery from the VIIRS instrument on the Suomi NPP satellite and surface-based measurements from the Environmental Protection Agency-Air Quality System (EPA-AQS) were analyzed over the span of 2013-2021 throughout central California to assess trends and seasonal variability. Dust events occurring between October 15, 2019 to November 30, 2019 in Fresno, CA and Madera, CA were selected for further analysis. The coarse particulate matter was calculated from surface based measurements and was compared to the Aerosol Optical Depth (AOD) and the Angstrom Exponent (AE) from the satellites. The dust events during this time period often corresponded to an increase in AOD and a decrease in AE when the concentration of coarse PM was high. This initial investigation further supports the use of satellite data for identifying dust events.