Evaluation of a coherent 2-µm differential absorption lidar for water vapor and radial wind velocity measurements
Hironori Iwai, Makoto Aoki
Abstract
The performance of a coherent 2-µm differential absorption lidar (DIAL) for simultaneously measuring water vapor (H 2 O) and radial wind velocity was evaluated. For measuring H 2 O, a wavelength locking technique was applied to the H 2 O-DIAL system. The H 2 O-DIAL system was evaluated under summer daytime conditions in Tokyo, Japan. H 2 O-DIAL measurements were compared with measurements from radiosondes. The H 2 O-DIAL-derived volumetric humidity values agreed with the radiosonde-derived values over the range from 11 to 20 g/m 3 with a correlation coefficient of 0.81 and a root-mean-square difference of 1.46 g/m 3 . Comparisons between the H 2 O-DIAL and the in-situ surface meteorological sensors demonstrated the simultaneous measurement of H 2 O and radial wind velocity.