Evaluation of a coherent 2-µm differential absorption lidar for water vapor and radial wind velocity measurements.

Abstract

The performance of a coherent 2-µm differential absorption lidar (DIAL) for simultaneously measuring water vapor (H2O) and radial wind velocity was evaluated. For measuring H2O, a wavelength locking technique was applied to the H2O-DIAL system. The H2O-DIAL system was evaluated under summer daytime conditions in Tokyo, Japan. H2O-DIAL measurements were compared with measurements from radiosondes. The H2O-DIAL-derived volumetric humidity values agreed with the radiosonde-derived values over the range from 11 to 20 g/m3 with a correlation coefficient of 0.81 and a root-mean-square difference of 1.46 g/m3. Comparisons between the H2O-DIAL and the in-situ surface meteorological sensors demonstrated the simultaneous measurement of H2O and radial wind velocity.