 |
| Titel |
Determination and analysis of in situ spectral aerosol optical properties by a multi-instrumental approach |
| VerfasserIn |
S. Segura, V. Estellés, G. Titos, H. Lyamani, M. P. Utrillas, P. Zotter, A. S. H. Prévôt, G. Mocnik, L. Alados-Arboledas, J. A. Martínez-Lozano |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1867-1381
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Measurement Techniques ; 7, no. 8 ; Nr. 7, no. 8 (2014-08-06), S.2373-2387 |
| Datensatznummer |
250115863
|
| Publikation (Nr.) |
 copernicus.org/amt-7-2373-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| Continuous in situ measurements of aerosol optical properties were conducted
from 29 June to 29 July 2012 in Granada (Spain) with a seven-wavelength
Aethalometer, a Multi-Angle Absorption Photometer, and a three-wavelength
integrating nephelometer. The aim of this work is to describe a methodology
to obtain the absorption coefficients (babs) for the different
Aethalometer wavelengths. In this way, data have been compensated using
algorithms which best estimate the compensation factors needed. Two
empirical factors are used to infer the absorption coefficients from the
Aethalometer measurements: C – the parameter describing the enhancement of
absorption by particles in the filter matrix due to multiple scattering of
light in the filter matrix – and f, the parameter compensating for
non-linear loading effects in the filter matrix. Spectral dependence of f
found in this study is not very strong. Values for the campaign lie in the
range from 1.15 at 370 nm to 1.11 at 950 nm. Wavelength dependence in C proves to be more important, and also more difficult to calculate. The
values obtained span from 3.42 at 370 nm to 4.59 at 950 nm. Furthermore, the
temporal evolution of the Ångström exponent of absorption (αabs)
and the single-scattering albedo (ω0) is presented.
On average αabs is around 1.1 ± 0.3, and ω0
is 0.78 ± 0.08 and 0.74 ± 0.09 at 370 and 950 nm,
respectively. These are typical values for sites with a predominance of
absorbing particles, and the urban measurement site in this study is such.
The babs average values are of 16 ± 10 Mm−1 (at 370 nm) and
5 ± 3 Mm−1 (at 950 nm), respectively. Finally, differences
between workdays and Sundays have been further analysed, obtaining
higher babs and lower ω0 during the workdays
than on Sundays as a consequence of the diesel traffic influence. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|