Narrowband sodium lidar for the measurements of mesopause region temperature and wind

Abstract

We report here a narrowband high-spectral resolution sodium temperature/wind lidar recently developed at the University of Science and Technology of China (USTC) in Hefei, China (31.5 °N, 117 °E). Patterned after the Colorado State University (CSU) narrowband sodium lidar with a dye laser-based transmitter, the USTC sodium temperature/wind lidar was deployed with a number of technical improvements that facilitate automation and ease of operation; these include a home constructed pulsed dye amplifier (PDA), a beam-steering system, a star-tracking program, and an electronic timing control. With the averaged power of ∼1.2 W output from PDA and the receiving telescope diameter of 0.76 m, our lidar system has a power aperture product of ∼0.55 Wm(2) and is comparable to the CSU and the University of Illinois at Urbana-Champaign (UIUC) sodium lidar systems. The uncertainties of typical measurements induced by photon noise and laser locking fluctuation for the temperature and wind with a 2 km vertical and 15 min temporal resolutions under the nighttime clear sky condition are estimated to be ∼1.0 K and ∼1.5 m/s, respectively, at the sodium peak (e.g., 91 km), and 8 K and 10 m/s, respectively, at both sodium layer edges (e.g., 81 km and 105 km). The USTC narrowband sodium lidar has been operated regularly during the night since November 2011. Using the initial data collected, we demonstrate the reliability and suitability of these high resolution and precision datasets for studying the wave perturbations in the mesopause region.