Water-vapor mixing-ratio measurements in the solar-blind region

It is shown that, under clear sky conditions, water-vapor mixing-ratio meas urements by solar-blind Raman lidars can be improved if the differential tr ansmissivity is calculated by use of a single Raman signal instead of the u sual Raman differential absorption lidar method, which allows one to exploi t the large absorption cross section of ozone in this spectral region. We p resent a discussion of statistical and systematic errors in both methods an d show the results of a numerical simulation. (C) 2000 Optical Society of A merica.