A Low-Cost Atmospheric Aerosol Monitoring System for Boundary Layer Air Quality, Visibility, Cloud Ceiling Height and Aerosol Properties

This proposal addresses subtopic 9.6.01, Low-cost Oceanic and Atmospheric Sensors and Observing Systems. It is proposed that two instruments for measuring atmospheric aerosols be commercialized to operate automatically and routinely. Both instruments have been used in research settings for many years and share several aspects of technology. They could both be commercialized with significant advantages in cost and performance over currently available instruments. The first is the CLidar which measures aerosol profiles and also operates as a star-photometer to measure aerosol optical depth (AOD). Visibility and cloud ceiling are directly calculated from the data collected. The CLidar is currently limited to twilight and nighttime conditions but use of an infrared camera and laser may allow daytime operation. The second instrument is an imaging polar nephelometer (IPN) that has been patented by the principle investigator. The IPN gives a detailed in-situ measurement, day and night, of scattered light from aerosols. The IPN measures the angular dependence of the scattered light. There are many commercial integrating nephelometers available but much information is lost when only the total scattered light is measured. The IPN has an excellent potential for measuring detailed aerosol properties relating to the aerosol size distribution, composition and shape.