Abstract

In this paper we present high spatial resolution lidar wind measurements with the edge technique using a ground based lidar system we have recently developed. The edge technique [1],[2] allows measurement of small frequency shifts such as the Doppler shift of an atmospheric backscattered signal from a pulsed laser. This yields a direct measurement of the wind along the line of sight of the laser beam. The edge technique can be used for high spatial resolution, high accuracy ground and airborne wind measurement as well as high accuracy spaceborne wind measurement. We show that line of sight wind profiles with a vertical resolution of 22 m have a standard deviation of 0.4 m/s for a 10 shot average. Validation data using independent rawinsonde and optical theodolite measurements show good agreement with the lidar wind measurements at the 1 m/s level. The instrument noise level for the lidar data is 0.11 m/s. This is a unique capability and provides valuable information for studies of turbulent processes in the lower atmosphere. This capability could also be used for high sensitivity detection of wind shear and microbursts in the vicinity of airports. Simulations show the edge technique can be used from satellites to obtain global wind measurements with an accuracy of the order of 1 m/s and a vertical resolution of 1 km through the troposphere. Such a system could make eyesafe wind measurements using well developed diode pumped solid state laser technology at 1.06 µm. Multi-pulse averaging would provide a spatially representative wind measurement. In addition, at ultraviolet wavelengths the Rayleigh backscatter could be used and would provide a large signal but with reduced measurement sensitivity.

© 1997 Optical Society of America