RAMAN LIDAR PROFILING OF ATMOSPHERIC WATER-VAPOR - SIMULTANEOUS MEASUREMENTS WITH 2 COLLOCATED SYSTEMS

Raman lidar is a leading candidate for providing the detailed space- a nd time-resolved measurements of water vapor needed by a variety of at mospheric studies. Simultaneous measurements of atmospheric water vapo r are described using two collocated Raman lidar systems. These lidar systems, developed at the NASA/Goddard Space Flight Center and Sandia National Laboratories, acquired approximately 12 hours of simultaneous water vapor data during three nights in November 1992 while the syste ms were collocated at the Goddard Space Flight Center. Although these lidar systems differ substantially in their design, measured water vap or profiles agreed within 0.15 g kg-1 between altitudes of 1 and 5 km. Comparisons with coincident radiosondes showed all instruments agreed within 0.2 g kg-1 in this same altitude range. Both lidars also clear ly showed the advection of water vapor in the middle troposphere and t he pronounced increase in water vapor in the nocturnal boundary layer that occurred during one night.