Lidar-Measured Winds from Space: A Key Component for Weather and Climate Prediction

Abstract

The deployment of a space-based Doppler lidar would provide information that is fundamental to advancing the understanding and prediction of weather and climate. This paper reviews the concepts of wind measurement by Doppler lidar, highlights the results of some observing system simulation experiments with lidar winds, and discusses the important advances in earth system science anticipated with lidar winds. Observing system simulation experiments, conducted using two different general circulation models, have shown 1) that there is a significant improvement in the forecast accuracy over the Southern Hemisphere and tropical oceans resulting from the assimilation of simulated satellite wind data, and 2) that wind data are significantly more effective than temperature or moisture data in controlling analysis error. Because accurate wind observations are currently almost entirely unavailable for the vast majority of tropical cyclones worldwide, lidar winds have the potential to substantially improve tropical cyclone forecasts. Similarly, to improve water vapor flux divergence calculations, a direct measure of the ageostrophic wind is needed since the present level of uncertainty cannot be reduced with better temperature and moisture soundings alone.

Estimate of Boundary-Layer Depth Over Beijing, China, Using Doppler Lidar Data During SURF-2015

“…Satellite-based lidar has the potential to provide wind measurements in regions not sampled by radiosondes or tracking of clouds or other features (Baker et al 1995;Devara et al 2015). With improvements in high-energy pulsed lasers, advanced lidars with low-noise detectors and high optical quality telescopes have been evaluated for wind measurements at ranges up to 10 km, and with low aerosol/cloud droplet concentrations (e.g., Frehlich et al 1994;Rhodes and Lundquist 2013;Devara et al 2015).…”

Wind Profiling with an Eye-Safe Coherent Doppler Lidar System: Comparison with Radiosondes and VHF Radar

“…A compact Doppler lidar system can be designed so that it is suitable for use as a mobile system, as an airborne system, and probably as a space-borne system. Several groups have investigated the impact of global winds on numerical weather prediction by using a space-borne Doppler lidar system (Rohaly and Krishinamurti 1993;Baker et al 1995;Atlas 1997). Ground-based coherent and incoherent Doppler lidar systems (e.g., Kavaya et al 1989;Shibata et al 1991;Post and Cupp 1992;Henderson et al 1993;Souprayen et al 1999;Cohn et al 2000;Gentry et al 2000;Flesia et al 2000;Grund et al 2001), and airborne coherent Doppler lidar systems (Bilbro et al 1984;Targ et al 1996;Rothermel et al 1998;Werner et al 2001) have been developed for wind measurements.…”

Jet Stream Winds: Comparisons of Aircraft Observations with Analyses

“…If the problem is due to sparse or inaccurate observational data, the next generation of possible and planned satellite instruments [Atmospheric Infrared Sounder, NASA (1993a); Laser Atmospheric Wind Sounder, Baker et al (1995)] may help, but their input will not be available until the turn of the century. If the problem is intrinsic to the reso-lution of finite grid general circulation models, recent results indicate that increases in horizontal resolution produce decreasing medium-range forecast improvements [A. Hollingsworth, European Centre for Medium-Range Weather Forecasts (ECMWF), 1994, personal communication].…”