Abstract

In this paper we present a technique for estimating optical backscatter and extinction profiles using lidar, which exploits the difference between the observed linear volume depolarization ratio at 355 nm and the corresponding expected aerosol-only depolarization ratio. The technique is specific to situations where a single strongly depolarizing species is present and the associated linear particulate depolarization ratio may be presumed to be known to within a reasonable degree of accuracy (on the order of 10%). The basic principle of the technique is extended to deal with situations where a depolarizing fraction is mixed with nondepolarizing aerosol. In general, since the relative depolarization interchannel calibration is much more stable than the absolute system calibration, the depolarization-based technique is easier to implement than conventional techniques that require a profile-by-profile calibration or, equivalently, an identification of aerosol-free altitude intervals. This in particular allows for unattended data analysis and makes the technique well-suited to be part of a broader (volcanic ash) surveillance system. The technique is demonstrated by applying it to the analysis of aerosol layers resulting from the 2010 eruptions of the Eyjafjallajökull volcano in Iceland. The measurements were made at the Cabauw remote-sensing site in the central Netherlands. By comparing the results of the depolarization-based inversion with a more conventional manual inversion procedure as well as Raman lidar results, it is demonstrated that the technique can be successfully applied to the particular case of 355 nm depolarization lidar volcanic ash soundings, including cases in which the ash is mixed with nondepolarizing aerosol.

© 2013 Optical Society of America

Practical depolarization-ratio-based inversion procedure: lidar measurements of the Eyjafjallajökull ash cloud over the Netherlands: erratum

D. P. Donovan and A. Apituley
Appl. Opt. 52(17) 4062-4062 (2013)

Aerosol lidar intercomparison in the framework of the EARLINET project. 3. Raman lidar algorithm for aerosol extinction, backscatter, and lidar ratio

Gelsomina Pappalardo, Aldo Amodeo, Marco Pandolfi, Ulla Wandinger, Albert Ansmann, Jens Bösenberg, Volker Matthias, Vassilis Amiridis, Ferdinando De Tomasi, Max Frioud, Marco Iarlori, Leonce Komguem, Alexandros Papayannis, Francesc Rocadenbosch, and Xuan Wang
Appl. Opt. 43(28) 5370-5385 (2004)

Vertical profiles of pure dust and mixed smoke–dust plumes inferred from inversion of multiwavelength Raman/polarization lidar data and comparison to AERONET retrievals and in situ observations

Detlef Müller, Igor Veselovskii, Alexei Kolgotin, Matthias Tesche, Albert Ansmann, and Oleg Dubovik
Appl. Opt. 52(14) 3178-3202 (2013)

Inversion of water cloud lidar signals based on accumulated depolarization ratio

Gilles Roy and Xiaoying Cao
Appl. Opt. 49(9) 1630-1635 (2010)

Feasibility study of integral property retrieval for tropospheric aerosol from Raman lidar data using principal component analysis

Martin de Graaf, Arnoud Apituley, and David P. Donovan
Appl. Opt. 52(10) 2173-2186 (2013)