Optical and microphysical characterization of aerosol layers over South Africa by means of multi-wavelength depolarization and Raman lidar measurements
Optical and microphysical properties of different aerosol types over South Africa measured with a multi-wavelength polarization Raman lidar are presented. This study could assist in bridging existing gaps relating to aerosol properties over South Africa, since limited long-term data of this type...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2016-07-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/16/8109/2016/acp-16-8109-2016.pdf |
| _version_ | 1811201069109215232 |
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| author | E. Giannakaki E. Giannakaki P. G. van Zyl D. Müller D. Balis M. Komppula |
| author_facet | E. Giannakaki E. Giannakaki P. G. van Zyl D. Müller D. Balis M. Komppula |
| author_sort | E. Giannakaki |
| collection | DOAJ |
| description | Optical and microphysical properties of different aerosol types
over South Africa measured with a multi-wavelength polarization Raman lidar
are presented. This study could assist in bridging existing gaps relating to
aerosol properties over South Africa, since limited long-term data of this
type are available for this region. The observations were performed under the
framework of the EUCAARI campaign in Elandsfontein. The multi-wavelength
Polly<sup>XT</sup> Raman lidar system was used to determine vertical profiles of
the aerosol optical properties, i.e. extinction and backscatter coefficients,
Ångström exponents, lidar ratio and depolarization ratio. The mean
microphysical aerosol properties, i.e. effective radius and single-scattering
albedo, were retrieved with an advanced inversion algorithm. Clear differences
were observed for the intensive optical properties of atmospheric layers of
biomass burning and urban/industrial aerosols. Our results reveal a wide
range of optical and microphysical parameters for biomass burning aerosols.
This indicates probable mixing of biomass burning aerosols with desert dust
particles, as well as the possible continuous influence of urban/industrial
aerosol load in the region. The lidar ratio at 355 nm, the lidar ratio at 532 nm, the linear particle depolarization ratio at 355 nm and the
extinction-related Ångström exponent from 355 to 532 nm were 52 ± 7 sr, 41 ± 13 sr, 0.9 ± 0.4 % and 2.3 ± 0.5,
respectively, for urban/industrial aerosols, while these values were 92 ± 10 sr, 75 ± 14 sr, 3.2 ± 1.3 % and
1.7 ± 0.3,
respectively, for biomass burning aerosol layers. Biomass burning particles
are larger and slightly less absorbing compared to urban/industrial
aerosols. The particle effective radius were found to be 0.10 ± 0.03, 0.17 ± 0.04 and 0.13 ± 0.03 µm for
urban/industrial, biomass burning, and mixed aerosols, respectively, while
the single-scattering albedo at 532 nm was 0.87 ± 0.06, 0.90 ± 0.06, and 0.88 ± 0.07 (at 532 nm), respectively, for these three types
of aerosols. Our results were within the same range of previously reported
values. |
| first_indexed | 2024-04-12T02:14:42Z |
| format | Article |
| id | doaj.art-9362b3571774453987dc95a241781f21 |
| institution | Directory Open Access Journal |
| issn | 1680-7316 1680-7324 |
| language | English |
| last_indexed | 2024-04-12T02:14:42Z |
| publishDate | 2016-07-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Chemistry and Physics |
| spelling | doaj.art-9362b3571774453987dc95a241781f212022-12-22T03:52:17ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242016-07-01168109812310.5194/acp-16-8109-2016Optical and microphysical characterization of aerosol layers over South Africa by means of multi-wavelength depolarization and Raman lidar measurementsE. Giannakaki0E. Giannakaki1P. G. van Zyl2D. Müller3D. Balis4M. Komppula5Finnish Meteorological Institute, P.O. Box 1627, 70211, Kuopio, Finlandon leave from: Department of Environmental Physics and Meteorology, Faculty of Physics, University of Athens, Athens, GreeceUnit for Environmental Sciences and Management, North-West University, Potchefstroom, South AfricaSchool of Physics, Astronomy and Mathematics, University of Hertfordshire, Hatfield, UKLaboratory of Atmospheric Physics, Thessaloniki, GreeceFinnish Meteorological Institute, P.O. Box 1627, 70211, Kuopio, FinlandOptical and microphysical properties of different aerosol types over South Africa measured with a multi-wavelength polarization Raman lidar are presented. This study could assist in bridging existing gaps relating to aerosol properties over South Africa, since limited long-term data of this type are available for this region. The observations were performed under the framework of the EUCAARI campaign in Elandsfontein. The multi-wavelength Polly<sup>XT</sup> Raman lidar system was used to determine vertical profiles of the aerosol optical properties, i.e. extinction and backscatter coefficients, Ångström exponents, lidar ratio and depolarization ratio. The mean microphysical aerosol properties, i.e. effective radius and single-scattering albedo, were retrieved with an advanced inversion algorithm. Clear differences were observed for the intensive optical properties of atmospheric layers of biomass burning and urban/industrial aerosols. Our results reveal a wide range of optical and microphysical parameters for biomass burning aerosols. This indicates probable mixing of biomass burning aerosols with desert dust particles, as well as the possible continuous influence of urban/industrial aerosol load in the region. The lidar ratio at 355 nm, the lidar ratio at 532 nm, the linear particle depolarization ratio at 355 nm and the extinction-related Ångström exponent from 355 to 532 nm were 52 ± 7 sr, 41 ± 13 sr, 0.9 ± 0.4 % and 2.3 ± 0.5, respectively, for urban/industrial aerosols, while these values were 92 ± 10 sr, 75 ± 14 sr, 3.2 ± 1.3 % and 1.7 ± 0.3, respectively, for biomass burning aerosol layers. Biomass burning particles are larger and slightly less absorbing compared to urban/industrial aerosols. The particle effective radius were found to be 0.10 ± 0.03, 0.17 ± 0.04 and 0.13 ± 0.03 µm for urban/industrial, biomass burning, and mixed aerosols, respectively, while the single-scattering albedo at 532 nm was 0.87 ± 0.06, 0.90 ± 0.06, and 0.88 ± 0.07 (at 532 nm), respectively, for these three types of aerosols. Our results were within the same range of previously reported values.https://www.atmos-chem-phys.net/16/8109/2016/acp-16-8109-2016.pdf |
| spellingShingle | E. Giannakaki E. Giannakaki P. G. van Zyl D. Müller D. Balis M. Komppula Optical and microphysical characterization of aerosol layers over South Africa by means of multi-wavelength depolarization and Raman lidar measurements Atmospheric Chemistry and Physics |
| title | Optical and microphysical characterization of aerosol layers over South
Africa by means of multi-wavelength depolarization and Raman lidar
measurements |
| title_full | Optical and microphysical characterization of aerosol layers over South
Africa by means of multi-wavelength depolarization and Raman lidar
measurements |
| title_fullStr | Optical and microphysical characterization of aerosol layers over South
Africa by means of multi-wavelength depolarization and Raman lidar
measurements |
| title_full_unstemmed | Optical and microphysical characterization of aerosol layers over South
Africa by means of multi-wavelength depolarization and Raman lidar
measurements |
| title_short | Optical and microphysical characterization of aerosol layers over South
Africa by means of multi-wavelength depolarization and Raman lidar
measurements |
| title_sort | optical and microphysical characterization of aerosol layers over south africa by means of multi wavelength depolarization and raman lidar measurements |
| url | https://www.atmos-chem-phys.net/16/8109/2016/acp-16-8109-2016.pdf |
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