Sodium Resonance Wind-Temperature Lidar at PFRR: Initial Observations and Performance

Abstract

A narrowband sodium resonance wind-temperature lidar (SRWTL) has been deployed at Poker Flat Research Range, Chatanika, Alaska (PFRR, 65° N, 147° W). Based on the Weber narrowband SRWTL, the PFRR SRWTL transmitter was upgraded with a state-of-the-art solid-state tunable diode laser as the seed laser. The PFRR SRWTL currently makes simultaneous measurements in the zenith and 20° off-zenith towards the north with two transmitted beams and two telescopes. Initial results for both nighttime and daytime measurements are presented. We review the performance of the PFRR SRWTL in terms of seven previous and currently operating SRWTLs. The transmitted power from the pulsed dye amplifier (PDA) is comparable with other SRWTL systems (900 mW). However, while the efficiency of the seeding and frequency shifting is comparable to other SRWTLs the efficiency of the pumping is lower. The uncertainties of temperature and wind measurements induced by photon noise at the peak of the layer with a 5 min, 1 km resolution are estimated to be ~1 K and 2 m/s for nighttime conditions, and 10 K and 6 m/s for daytime conditions. The relative efficiency of the zenith receiver is comparable to other SRWTLs (90–97%), while the efficiency of the north off-zenith receiver needs further optimization. An upgrade of the PFRR SRWTL to a full three-beam system with zenith, northward and eastward measurements is in progress.

Cloud Formation From a Localized Water Release in the Upper Mesosphere: Indication of Rapid Cooling

“…An SRWTL was deployed and upgraded to support the Super Soaker experiment (Li et al., 2020). The SRWTL used the three‐frequency technique to measure wind and temperature in the mesospheric sodium layer (∼80–100 km; Bills et al., 1991; Krueger et al., 2015; She et al., 1990).…”

Lidar Observations of Instability and Estimates of Vertical Eddy Diffusivity Induced by Gravity Wave Breaking in the Arctic Mesosphere

“…To characterize gravity-wave activity in the stratosphere and mesosphere, we choose a higher temporal resolution and calculate density profiles over 30 min intervals at 5 min steps in order to include higher frequencies of the GW spectrum. the measurements in 2018 were made with a narrowband sodium resonance wind-temperature lidar (Li et al, 2020).…”

“…The Sodium Resonance Wind‐Temperature Lidar (SRWTL) was installed at PFRR in 2017 and ongoing measurements of the sodium number density, temperature and meridional wind in the MLT (∼70–120 km) have been acquired since then (Li et al, 2020). A zonal wind channel was added in 2019 after the observations presented in this paper.…”

“…We use measurements from different sodium resonance lidar systems in this study. The measurements in 2009 and 2015 were made with a broadband sodium density resonance lidar (Triplett et al., 2018), while the measurements in 2018 were made with a narrowband sodium resonance wind‐temperature lidar (Li et al., 2020).…”

On the relationship between the mesospheric sodium layer and the meteoric input function

“…The sodium layer is usually studied via observations carried out by resonance lidars, satellites, and through Na D-line emission at 589.0nm and 589.6nm (Plane, 2010;Plane et al, 2012;Hedin and Gumbel, 2011;Langowski et al, 2017;Andrioli et al, 2019;Li et al, 2020a). The sodium vertical profiles retrieved by lidars have been commonly used as a tracer to study atmospheric dynamics, e.g., gravity waves, wind shear, etc.…”