Observation of clouds, aerosols, and precipitation by multiple-field-of-view multiple-scattering polarization lidar at 355 nm

We developed a multiple-field-of-view multiple-scattering polarization lidar at 355 nm (MFMSPL-355) to study the microphysics of clouds and aerosols, and understand the multiple scattering effects on space lidar measurements. The MFMSPL-355 is used to simulate and interpret multiple scattering signals by the 355 nm lidar installed on the Earth Clouds, Aerosol and Radiation Explorer satellite. This is the first multiple scattering lidar developed at 355 nm in the world. The system has five receiver modules and can observe both parallel and perpendicular attenuated backscatter coefficients for the on-beam direction and four off-beam directions with different tilting angles. Thus, the MFMSPL-355 can measure the single scattering signal and multiple scattering signal independently; accordingly, it can provide microphysical properties, such as the effective radius, of clouds and aerosols. We demonstrated that the MFMSPL-355 could observe multiple scattering signals for water clouds, ice clouds, aerosols, and drizzle. The observed features of the water clouds and drizzle were consistent with those observed by a previously developed 532-nm MFMSPL. Furthermore, we found that aerosol signals and their multiple scattering contributions were generally more pronounced at 355 nm, which is the advantage of performing measurements at 355 nm. Off-beam channels can offer a unique opportunity to study aerosol microphysics.