Development of a Multiple-Field-of-View Multiple-Scattering Polarization Lidar System at 355nm for Cloud Measurements

¹ National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506, Japan,
² Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasugakoen, Kasuga 816-8580, Japan
³ National Institute of Information and Communication Technology, 4-2-1 Nukiikitamachi, Koganei, 184-8795, Japan

^* Email: nisizawa@nies.go.jp

Published online: 7 July 2020

Abstract

We developed a multiple-filed-of view multiple-scattering polarization lidar (MFMSPL) at 355nm to study microphysics of optically thick clouds and understand multiple scattering effects on space lidar measurements (e.g., EarthCARE). This system is based on depolarization Mie lidar technique; it uses a compact receiver module including a small telescope, polarizer, and detectors to measure co-polar and cross-polar backscatter signals, separately. The MFMSPL system has all the 10 measurement channels. The MFMSPL uses the five receiver modules with FOV of 10mrad tilted with different zenith angles (θ); it measures on-beam signals (θ=0mrad) as well as four off-beam signals (θ=10,20,30,40mrad). This MFMSPL system was based on previously developed 532nm MFMSPL system, however, we made the system more stable, robust, and compact by integrating co-polar and cross-polar channels in the receiver module than the previous system. In addition, we improved the dynamic range of the measurement in nighttime by synergy use of analog and photon counting measurements. In the conference, we present the MFMSPL system, data analysis method including calibration method, and observation results.