Performance estimation of space-borne high-spectral-resolution lidar for cloud and aerosol optical properties at 532 nm.

Cloud and aerosol contribute with great uncertainty in Earth's radiative budget. There is an urgent need for global 3-D observation of these atmospheric constituents. High-spectral-resolution Lidar (HSRL) can obtain vertical atmosphere profile with high accuracy, hence several space-borne HSRLs are planned to launch in few years. However, as far as we know, the performance evaluation of space-borne HSRL has not been reported yet. In this paper, we present the characteristics of a new designed space-borne HSRL for aerosol and cloud optical property profiling (ACHSRL), which is part of the Aerosol & Carbon Detection Lidar (ACDL) developed in China. The ACHSRL is essentially similar to the famous Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), which is on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). Moreover, the ACHSRL employs an iodine absorption filter as the spectral discriminator. The atmospheric optical properties data observed by CALIOP is used to estimate the performance of ACHSRL. We chose the level 2 profile data (version 4.10) in South Japan in June 2015 to compare the detection uncertainty of ACHSRL and CALIOP. The simulation calculates the uncertainties of ACHSRL and makes a statistic analysis. The analysis result demonstrates that 73.63% of the backscatter coefficient uncertainties are below 40% for ACHSRL. By contrast, the number is 30.72% for CALIOP. As for absolute extinction coefficient errors, the statistics shows that 76.01% of the extinction coefficient uncertainties are lower than 0.2 km for ACHSRL, while that for CALIOP are 56.97%. The assessment shows that ACHSRL could measure the particulate optical properties with better accuracy and compared with CALIOP. The estimation in this study reveals that the next generation space-borne HSRLs have a promising future.