LIDAR IN-SPACE TECHNOLOGY EXPERIMENT MEASUREMENTS OF SEA-SURFACE DIRECTIONAL REFLECTANCE AND THE LINK TO SURFACE WIND-SPEED

The dependence of sea surface directional reflectance on surface wind stress suggests a method for deriving surface wind speed from space-ba sed lidar measurements of sea surface backscatter. In particular, lida r measurements in the nadir angle range from 10 degrees to 30 degrees appear to be most sensitive to surface wind-speed variability in the r egime below 10 m/s. The Lidar In-space Technology Experiment (LITE) sh uttle Lidar mission of September 1994 provided a unique opportunity to measure directional backscatter at selected locations by use of the l andmark track maneuver and to measure fixed-angle backscatter from the ocean surfaces on a global scale. During the landmark track maneuver the shuttle orbiter orientation and roll axis are adjusted continuousl y to maintain the lidar footprint at a fixed location for a duration o f similar to 1 min. Several data sets were converted to calibrated ref lectance units and compared with a surface reflectance model to deduce surface wind speeds. Comparisons were made with ERS-1 scatterometer d ata and surface measurements. (C) 1998 Optical Society of America.