Abstract

The Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR) at Andoya, Norway (69° N. 16°E. von Zahn and Rees, 1994), is a complex multi-instrument facility using lidars, radars and passive IR and Visible-wavelength instruments to study the complex behaviour of the Arctic Stratosphere and Mesosphere (von Cossart et al 1995). ALOMAR has recently been augmented with the commissioning of two large receiving telescopes which can be scanned in azimuth and elevation to permit wind velocity measurements to be obtained by the Doppler Wind and Temperature System (DWTS). The ALOMAR Rayleigh / Raman / Mie lidar uses two powerful Spectra-Physics GCR-6 Nd-YAG lasers. The power lasers are seeded by a LightWavc CW laser which is stabilised against an iodine line generated in an absorption cell. This laser has proved to be extremely stable, with drills of significantly less than lms⁻¹ during periods of 12 hours. Two steerable 1.8 m diameter receiving telescopes recover the atmospheric back-scattered signals, which are fed via libre-optic connections to a complex detection system which includes detectors for the fundamental (1064 nm), frequency-doubled (532 ran), and frequency-tripled (355 nm) laser emissions.

© 1996 IEEE