Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
Journal Home About Issues in Progress Current Issue All Issues Feature Issues

UV polarization lidar for remote sensing new particles formation in the atmosphere

Grégory David, Benjamin Thomas, Yoan Dupart, Barbara D’Anna, Christian George, Alain Miffre, and Patrick Rairoux

Open Access Open Access

Abstract

Understanding new particles formation in the free troposphere is key for air quality and climate change, but requires accurate observation tools. Here, we discuss on the optical requirements ensuring a backscattering device, such as a lidar, to remotely observe nucleation events promoted by nonspherical desert dust or volcanic ash particles. By applying the Mie theory and the T-matrix code, we numerically simulated the backscattering coefficient of spherical freshly nucleated particles and nonspherical particles. We hence showed that, to remotely observe such nucleation events with an elastic lidar device, it should operate in the UV spectral range and be polarization-resolved. Two atmospheric case studies are proposed, on nucleation events promoted by desert dust, or volcanic ash particles. This optical pathway might be useful for climate, geophysical and fundamental purposes, by providing a range-resolved remote observation of nucleation events.

© 2014 Optical Society of America

Full Article  |  PDF Article
More Like This
Lidar remote sensing of laser-induced incandescence on light absorbing particles in the atmosphere

Alain Miffre, Christophe Anselmo, Sylvain Geffroy, Emeric Fréjafon, and Patrick Rairoux
Opt. Express 23(3) 2347-2360 (2015)

Extinction-to-backscatter ratio of Asian dust observed with high-spectral-resolution lidar and Raman lidar

Zhaoyan Liu, Nobuo Sugimoto, and Toshiyuki Murayama
Appl. Opt. 41(15) 2760-2767 (2002)

Small lidar ratio of dust aerosol observed by Raman-polarization lidar near desert sources

Zhongwei Huang, Meishi Li, Jianrong Bi, Xingtai Shen, Shuang Zhang, and Qiantao Liu
Opt. Express 31(10) 16909-16919 (2023)

View More...

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)
Fig. 1
Fig. 1 Panel (a): Observation of the size and time evolution of the particles number concentration during a typical dust-NPF event, taken from a field campaign [18] on 2009 March 13th. Local time is used (UTC + 8h, Asian field campaign). The observed behavior between 9:00 and 12:00, then 18:00 to 19:00, is a clear signature of a NPF-event, while in the meantime, coarser dust particles, for diameters above 800 nm, are in low number concentrations. Panel (b): Numerical simulation of the backscattering coefficient βNPF obtained by applying the Mie theory at λ = 355 nm (blue), 532 nm (green), 1064 nm (red). The dust particles backscattering coefficient βdust, derived from T-matrix numerical simulation, is plotted at λ = 355 nm in light blue.

Download Full Size | PDF

Fig. 2
Fig. 2 (a) Size and wavelength dependence of the NPF-backscattering integrand (dσ/dΩ)NPF × nNPF during the NPF-event (at t = 10h45), as implied by Eq. (1). (b) Spectral dependence of the backscattering coefficient βNPF obtained by integrating graph (a) over the particles size distribution for spherical particles (diameters below 800 nm).

Download Full Size | PDF

Fig. 3
Fig. 3 Spectral dependence of molecular backscattering cross-section at λ = 355 nm numerically simulated for a standard atmosphere, for co-(black) and cross- (grey) polarized polarization components. Ro-vibrational molecular spectra appears spectrally smoothed due to the finite spectral linewidth of the laser emission (1 GHz), whose Doppler broadening is also included.

Download Full Size | PDF

Fig. 4
Fig. 4 Time-altitude maps of the lidar-retrieved backscattering coefficients {βp,//, βp,⊥}-coefficients, then {βs, βns}-backscattering coefficients measured at Lyon at λ = 355 nm in July 2010 during a Saharan dust outbreak. To put light on the achieved sensitivity, a different color code has been used for each map.

Download Full Size | PDF

Fig. 5
Fig. 5 Spherical (grey) and nonspherical (brown, dust) particles backscattering coefficient βs and βns as a function of altitude during a Saharan dust outbreak (Lyon, July 2010, 5h), together with the corresponding βp,// and βp,⊥-profiles. To ease the reading, the graph is limited to altitudes above the PBL where the dust cloud is present.

Download Full Size | PDF

Fig. 6
Fig. 6 Spherical (grey) and nonspherical (brown, ash) particles backscattering coefficient βs and βns as a function of altitude during a volcanic ash episode (Lyon, April 17th 2010, 12h), together with the corresponding βp,// and βp,⊥-profiles. To ease the reading, the graph is limited to altitudes above the PBL.

Download Full Size | PDF

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

β p ( λ ) = ∫ 0 D p , max ( d σ d Ω ) p ( D p , λ )   ×   n p ( D p ) d D p
β s = β s,// = β p,// − β ns,// = β p,// − β p,⊥ / δ ns
β ns = β ns,// + β ns,⊥ = β p,⊥ (1+1/ δ ns )
β p,// =( R // −1) β m, // and β p,⊥ =( R // δ− δ m ) β m,//
Select as filters
Select Topics Cancel
Top
       
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.
Privacy | Terms of Use