Sorry, you need to enable JavaScript to visit this website.

Airborne and ground-based measurements using a high-performance raman lidar

TitoloAirborne and ground-based measurements using a high-performance raman lidar
Tipo di pubblicazioneArticolo su Rivista peer-reviewed
Anno di Pubblicazione2010
AutoriWhiteman, D.N., Rush K., Rabenhorst S., Welch W., Cadirola M., McIntire G., Russo Felicita, Adam M., Venable D., Connell R., Veselovskii I., Forno R., Mielke B., Stein B., Leblanc T., McDermid S., and Vömel H.
RivistaJournal of Atmospheric and Oceanic Technology
Parole chiaveaerosol, Aerosol extinction, Aerosol instrument, Aerosol parameters, airborne sensing, Atmospheric aerosols, Atmospheric humidity, Atmospheric lidars, Atmospherics, California, Cloud droplet radii, Cloud liquid waters, Computer simulation, Design considerations, Differential absorption lidars, Diode pumped lasers, Experiments, Field campaign, Flight altitudes, Ground based, Ground based measurement, ground-based measurement, High spectral resolution lidars, Inter-agency collaboration, Interference filters, Internal combustion engines, Jet Propulsion Laboratory, Landforms, laser method, Laser performance, Laser power, lidar, Light extinction, Lower stratosphere, Measurements, Meteorological instruments, Number density, Numerical simulation, Optical radar, Performance characteristics, Pumping (laser), Raman lidar, Research aircraft, South Africa, Southern California, spatial resolution, stratosphere, Subaperture, Table Mountain, Temporal resolution, United States, Water absorption, Water vapor, Water vapor mixing ratio, Western Cape

A 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 ground-based 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 the MOHAVE-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 the WAVES_2007 campaign was a misaligned interference filter. With full laser power and a properly tuned interference filter, RASL is shown to be capable of measuring the main 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 demonstratea level of versatility in Raman lidar that may be impossible to duplicate with any other single lidar technique. © 2010 American Meteorological Society.


cited By 24

Citation KeyWhiteman20101781