Observation of Asian Dust Aerosols with Depolarization Lidar Using a Coherent White Light Continuum

We performed a lidar observation of Asian dust aerosols for the first time using a white light lidar system. The lidar used in the observation utilized a coherent white light continuum generated in Kr gas as a light source and was used as a three-wavelength Mie-scattering lidar having a depolarization measurement capability at 450, 550, and 800 nm. Lidar depolarization ratios of 0.30?0.70 at 800 nm were measured. These data reveal a higher depolarization ratio than usual (normally almost zero) in the lower troposphere. Thus, the white light lidar can identify Asian dust particles that pose a threat to cross-border pollution in Japan.