Title :

Retrievals of aerosol size distribution, spherical fraction, and complex refractive index from airborne in situ angular light scattering and absorption measurements

Author(s) :

Espinosa, W. Reed [Auteur]
Martins, Vanderlei [Auteur]
Remer, Lorraine [Auteur]
Doubovik, Oleg [Auteur]
Laboratoire d’Optique Atmosphérique - UMR 8518 [LOA]
Lapionak, Tatsiana [Auteur]
Laboratoire d'Optique Atmosphérique (LOA) - UMR 8518
Fuertes, David [Auteur]
Université de Lille
Puthukkudy, Anin [Auteur]
Orozco, Daniel [Auteur]
Ziemba, Luke [Auteur]
Thornhill, K. Lee [Auteur]
Levy, Robert [Auteur]

Journal title :

Journal of Geophysical Research: Atmospheres

Abbreviated title :

J. Geophys. Res.-Atmos.

Volume number :

124

Publication date :

2019-07-27

ISSN :

2169-897X

English keyword(s) :

aerosol
phase function
light scattering
light absorption
polar nephelometer
inversion

HAL domain(s) :

Physique [physics]

English abstract : [en]

Aerosol models, composed of size distribution, complex refractive index, and sphericalfraction, are derived from a new synergistic retrieval of airborne in situ angular scattering measurementsmade by the Polarized Imaging ...
Show more >Aerosol models, composed of size distribution, complex refractive index, and sphericalfraction, are derived from a new synergistic retrieval of airborne in situ angular scattering measurementsmade by the Polarized Imaging Nephelometer and absorption measurements from the Particle SootAbsorption Photometer. The data utilized include phase function (F11), degree of polarization (−F12∕F11),and absorption coefficient (��abs) measured at low relative humidities during the Studies of Emissions andAtmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC4RS) and DeepConvection Clouds and Chemistry (DC3) field campaigns. The Generalized Retrieval of Aerosol andSurface Properties (GRASP) is applied to these measurements to obtain summaries of particle propertiesthat are optically consistent with the original measurements. A classification scheme is then used tocategorize the corresponding retrieval results. Inversions performed on the DC3 measurements indicatethe presence of a significant amount of dust-like aerosol in the inflow of storms sampled during thiscampaign, with the quantity of dust present depending strongly on the underlying surface features. In theSEAC4RS data, the retrieved size distributions were found to be remarkably similar among a range ofaerosol types, including urban and industrial, biogenic, and biomass burning (BB) emissions. Theseaerosol types were found to have average fine mode volume median radii0.155≤rvf≤0.163μm andlognormal standard deviations0.32≤��f≤0.36. There were, however, consistent differences between theangular scattering patterns of the BB samples and the other particle types. The GRASP retrievalpredominantly attributed these differences to elevated real and imaginary refractive indices in the BBsamples (m532nm≈1.55+0.007i) relative to the two other categories (m532nm≈1.51+0.004i).Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Collections :

• Laboratoire d'Optique Atmosphérique (LOA) - UMR 8518

Submission date :

2024-01-30T11:45:51Z
2024-02-26T13:23:47Z