Grant: Research Tools and Instruments - Category 1 (<$150,000)

The World Health Organization estimates that exposure to fine particulate matter (PM2.5) is the leading environmentally-related cause of premature mortality worldwide. Ground-based observations have insufficient coverage at the global scale to assess long-term human exposure to PM2.5. Satellite remote sensing offers promising prospects for providing information on exposure to PM2.5 at regional-to-global scales, but there are limitations and outstanding questions about the accuracy and precision with which ground-level aerosol mass concentrations can be inferred from satellite remote sensing. A key source of uncertainty is the global distribution of the relationship of annual average PM2.5 with columnar aerosol optical depth at specific overpass times during cloud-free conditions. We propose instrumentation for ground-level monitoring stations designed to evaluate and enhance satellite remote sensing estimates for application in health effects research and risk assessment. The proposed instrumentation would measure hourly PM2.5 primarily in highly populated regions in close proximity to existing ground-based sun photometers that measure aerosol optical depth. As a result, this instrumentation would enable critical measurements to evaluate and improve global estimates of PM2.5 exposure.