Estimates of aerosol radiative forcing would benefit from new techniques for measuring light extinction and scattering by atmospheric aerosols. Of particular interest is the ratio between aerosol scattering coefficient and extinction coefficient, known as the aerosol single scatter albedo. In this work, a new instrument for the determination of aerosol albedo at 532 nm will be designed, constructed, and tested. The method employs a cavity ring-down based extinction measurement inside an integrating sphere. Light that is scattered from the ring-down beam by aerosols will be collected by the sphere in order to measure the aerosol scattering coefficient. Work will be undertaken to characterize the performance of the instrument, understand its limitations, and demonstrate its utility for monitoring aerosol extinction coefficient, scattering coefficient and albedo. Throughout the effort, undergraduate students will work with the PI to design the instrument, and collect and analyze the resultant data. This research will provide students with a background in optical measurements, electronics, lasers, and atmospheric aerosols. The students will be encouraged to present their research results at national conferences. As such, the experience will supplement the students' normal coursework and significantly broaden their undergraduate experience. Broader impacts also include enhancement of research infrastructure at the PI's institution.
