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Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Allen, Robert J. Browell, Edward V. Grant, William B. Ponsardin, Patrick Higdon, Noah S. Mayo, M. Neale Butler, Carolyn F. Grossman, Benoist E. Ismail, Syed Hueser, Alene W. Carter, Arlen F. Mayor, Shane D. |
| Copyright Year | 1994 |
| Description | An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H2O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and greater than 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H2O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H2O absorption-line parameters were performed to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H2O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H2O radiosondes. The H2O distributions measured with the DIAL system differed by less than 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions. |
| File Size | 1734652 |
| Page Count | 24 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19960028782 |
| Archival Resource Key | ark:/13960/t27993h2z |
| Language | English |
| Publisher Date | 1994-09-20 |
| Access Restriction | Open |
| Subject Keyword | Meteorology And Climatology Differential Absorption Lidar Absorption Spectroscopy Water Alexandrite Dew Point Data Acquisition Signal To Noise Ratios Photomultiplier Tubes Atmospheric Moisture Hygrometers Remote Sensing Airborne Equipment Solid State Lasers Radiosondes Aerosols Absorption Cross Sections Optical Radar Meteorology Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
