Integration of Satellite Observations with Low-Cost Air Quality Monitors

PM_2.5, or fine particulate matter, is a category of air pollutant consisting of particles with effective aerodynamic diameter equal to or less than 2.5 micrometers. These particles have been linked to human health impacts as well as regional haze, visibility, and climate change issues. Due to cost and space restrictions, the standard monitoring network remains spatially sparse. To increase the spatial resolution of monitoring, previous studies have used satellite data to estimate ground-level PM concentrations, despite these estimates being associated with moderate to large uncertainties when relating a column measure of aerosol (aerosol optical depth or AOD) with surface measurements. Here, we discuss the role of low-cost air-quality monitor (LCAQM) and satellite observations in monitoring air quality. We will evaluate the LCAQM measurements with those obtained from standard measurements under low, moderate and high pollution conditions. We will also present a frame work to integrate LCAQM data with NASA satellite observations for real time air quality monitoring. We will also present an application of LCAQM and satellite data for quantifying the impact of wildfires in CA during October 2017. The impacts of fires on PM_2.5 concentration at varying temporal (hourly, daily, weekly) and spatial (local to regional) scales have been evaluated. Finally, we will highlight lessons learnt and challenges associated with both LCAQM and satellite-based PM_2.5 measurements around the globe.