Researchers at the Max-Planck-Institut für Meteorologie are developing a ground-based differential absorption lidar technique to remotely monitor water vapor and take wind measurements. A frequency-doubled Nd:YVO laser pumps a continuous-wave single-frequency Ti:sapphire ring laser. The major advantage of the system is its ability to provide water vapor profiles with high resolution during the day.The system exhibits less than a 5 percent margin of error in the absolute humidity for the water vapor measurements. V. Wulfmeyer of the institute presented the team's findings at the Conference on Lasers and Electro-Optics in Baltimore, saying that the technique will be useful for weather forecasting in aerospace applications.