High-resolution Doppler lidar for boundary layer and cloud research

The high-resolution Doppler lidar (HRDL) was developed to provide higher sp atial, temporal, and velocity resolution and more reliable performance than was previously obtainable with CO2-laser-based technology. The improved pe rformance is needed to support continued advancement of boundary layer simu lation models and to facilitate high-resolution turbulent flux measurements . HRDL combines a unique, eye-safe, near-IR-wavelength, solid-state laser t ransmitter with advanced signal processing and a high-speed scanner to achi eve 30-m range resolution and a velocity precision of similar to 10 cm s(-1 ) under a variety of marine and continental boundary layer conditions, depe nding on atmospheric and operating conditions. An attitude-compensating sca nner has been developed to facilitate shipboard marine boundary layer obser vations. Vertical velocities, fine details of the wind profile near the sur face, turbulence kinetic energy profiles, and momentum flux are measurable with HRDL. The system is also useful for cloud studies. The HRDL technology , capabilities, and field performance are discussed.