Evaluating the Consistency of Atmospheric Aerosol Measurements from Ground-based and Space-based Optical Instruments

Aerosols are small floating particles which influence a wide variety of atmospheric phenomenon, from air quality to cloud formation. Their detection and monitoring form a vital part of the study of the atmosphere and climate. Aerosol Optical Depth (AOD) is one parameter that provides information on the atmospheric aerosol burden. This study combines ground-based and space-based observations to assess consistency between AOD measurment methods. Lidar is an often used and reliable instrument which can give insight on vertical aerosol structure, but the costs and mobile inflexibility of traditional lidar systems can limit measurements in certain situations. Camera Lidar (CLidar) provides an inexpensive supplement for measuring certain tropospheric aerosol properties in its place. For nighttime aerosol scattering, our novel experimental setup utilizes an astronomical CCD camera that captures the signal of a 532 nm 5 W laser. We then apply an aerosol scattering phase function to the signal to produce vertically resolved aerosol extinction, then integrat through the height of the atmosphere to derive AOD. We compare our AOD calculations to daytime measurements from solar radiometers, which measure the optical depth in the entire vertical column of the atmosphere without altitude resolution. We also compare findings with satellite data over the experimental region. Results show consistency between the various methods, supporting future implementation of Camera Lidar as an aerosol detection method.