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Airborne and Ground-Based Measurements Using a High-Performance Raman LidarA high-performance Raman lidar operating in the UV portion of the spectrum has been used to acquire, for the first time using a single lidar, simultaneous airborne profiles of the water vapor mixing ratio, aerosol backscatter, aerosol extinction, aerosol depolarization and research mode measurements of cloud liquid water, cloud droplet radius, and number density. The Raman Airborne Spectroscopic Lidar (RASL) system was installed in a Beechcraft King Air B200 aircraft and was flown over the mid-Atlantic United States during July August 2007 at altitudes ranging between 5 and 8 km. During these flights, despite suboptimal laser performance and subaperture use of the telescope, all RASL measurement expectations were met, except that of aerosol extinction. Following the Water Vapor Validation Experiment Satellite/Sondes (WAVES_2007) field campaign in the summer of 2007, RASL was installed in a mobile trailer for groundbased use during the Measurements of Humidity and Validation Experiment (MOHAVE-II) field campaign held during October 2007 at the Jet Propulsion Laboratory s Table Mountain Facility in southern California. This ground-based configuration of the lidar hardware is called Atmospheric Lidar for Validation, Interagency Collaboration and Education (ALVICE). During theMOHAVE-II field campaign, during which only nighttime measurements were made, ALVICE demonstrated significant sensitivity to lower-stratospheric water vapor. Numerical simulation and comparisons with a cryogenic frost-point hygrometer are used to demonstrate that a system with the performance characteristics of RASL ALVICE should indeed be able to quantify water vapor well into the lower stratosphere with extended averaging from an elevated location like Table Mountain. The same design considerations that optimize Raman lidar for airborne use on a small research aircraft are, therefore, shown to yield significant dividends in the quantification of lower-stratospheric water vapor. The MOHAVE-II measurements, along with numerical simulation, were used to determine that the likely reason for the suboptimal airborne aerosol extinction performance during theWAVES_2007 campaign was amisaligned interference filter. With full laser power and a properly tuned interference filter,RASL is shown to be capable ofmeasuring themain water vapor and aerosol parameters with temporal resolutions of between 2 and 45 s and spatial resolutions ranging from 30 to 330 m from a flight altitude of 8 km with precision of generally less than 10%, providing performance that is competitive with some airborne Differential Absorption Lidar (DIAL) water vapor and High Spectral Resolution Lidar (HSRL) aerosol instruments. The use of diode-pumped laser technology would improve the performance of an airborne Raman lidar and permit additional instrumentation to be carried on board a small research aircraft. The combined airborne and ground-based measurements presented here demonstrate a level of versatility in Raman lidar that may be impossible to duplicate with any other single lidar technique.
Document ID
20110016137
Document Type
Reprint (Version printed in journal)
Authors
Whiteman, David N. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Rush, Kurt (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Rabenhorst, Scott (Maryland Univ. College Park, MD, United States)
Welch, Wayne (Welch Mechanical Designs Belcamp, MD, United States)
Cadirola, Martin (Ecotronics, LLC Clarksburg, MD, United States)
McIntire, Gerry (SGT, Inc. Lanham , MD, United States)
Russo, Felicita (Consiglio Nazionale delle Ricerche Potenza, Italy)
Adam, Mariana (Joint Research Centre of the European Communities Ispra, Italy)
Venable, Demetrius (Howard Univ. Washington, DC, United States)
Connell, Rasheen (Howard Univ. Washington, DC, United States)
Veselovskii, Igor (Maryland Univ. Baltimore County Baltimore, MD, United States)
Forno, Ricardo (Universidad Mayor de San Andres La Paz, Bolivia)
Mielke, Bernd (Licel Berlin, Germany)
Stein, Bernhard (Licel Berlin, Germany)
Leblanc, Thierry (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
McDermid, Stuart (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Voemel, Holger (Lindenberg Observatory Lindenberg, Germany)
Date Acquired
August 25, 2013
Publication Date
November 1, 2010
Publication Information
Publication: Journal of Atmospheric and Oceanic Technology
Volume: 27
Issue: 11
ISSN: 0739-0572
Subject Category
Meteorology and Climatology
Distribution Limits
Public
Copyright
Other