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| Titel |
Synergetic monitoring of Saharan dust plumes and potential impact on surface: a case study of dust transport from Canary Islands to Iberian Peninsula |
| VerfasserIn |
C. Córdoba-Jabonero, M. Sorribas, J. L. Guerrero-Rascado, J. A. Adame, Y. Hernández, H. Lyamani, V. Cachorro, M. Gil, L. Alados-Arboledas, E. Cuevas, B. Morena |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 7 ; Nr. 11, no. 7 (2011-04-01), S.3067-3091 |
| Datensatznummer |
250009580
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| Publikation (Nr.) |
 copernicus.org/acp-11-3067-2011.pdf |
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| Zusammenfassung |
| The synergetic use of meteorological information, remote sensing both
ground-based active (lidar) and passive (sun-photometry) techniques together
with backtrajectory analysis and in-situ measurements is devoted to the
characterization of dust intrusions. A case study of air masses advected
from the Saharan region to the Canary Islands and the Iberian Peninsula,
located relatively close and far away from the dust sources, respectively,
was considered for this purpose. The observations were performed over three
Spanish geographically strategic stations within the dust-influenced area
along a common dust plume pathway monitored from 11 to 19 of March 2008. A
4-day long dust event (13–16 March) over the Santa Cruz de Tenerife
Observatory (SCO), and a linked short 1-day dust episode (14 March) in the
Southern Iberian Peninsula over the Atmospheric Sounding Station "El
Arenosillo" (ARN) and the Granada station (GRA) were detected.
Meteorological conditions favoured the dust plume transport over the area
under study. Backtrajectory analysis clearly revealed the Saharan region as
the source of the dust intrusion. Under the Saharan air masses influence,
AERONET Aerosol Optical Depth at 500 nm (AOD500) ranged from 0.3 to 0.6
and Ångström Exponent at 440/675 nm wavelength pair (AE440/675)
was lower than 0.5, indicating a high loading and predominance of coarse
particles during those dusty events. Lidar observations characterized their
vertical layering structure, identifying different aerosol contributions
depending on altitude. In particular, the 3-km height dust layer transported
from the Saharan region and observed over SCO site was later on detected at
ARN and GRA stations. No significant differences were found in the lidar
(extinction-to-backscatter) ratio (LR) estimation for that dust plume over
all stations when a suitable aerosol scenario for lidar data retrieval is
selected. Lidar-retrieved LR values of 60–70 sr were obtained during the
main dust episodes. These similar LR values found in all the stations
suggest that dust properties were kept nearly unchanged in the course of its
medium-range transport. In addition, the potential impact on surface of that
Saharan dust intrusion over the Iberian Peninsula was evaluated by means of
ground-level in-situ measurements for particle deposition assessment
together with backtrajectory analysis. However, no connection between those
dust plumes and the particle sedimentation registered at ground level is
found. Differences on particle deposition processes observed in both
Southern Iberian Peninsula sites are due to the particular dust transport
pattern occurred over each station. Discrepancies between
columnar-integrated and ground-level in-situ measurements show a clear
dependence on height of the dust particle size distribution. Then, further
vertical size-resolved observations are needed for evaluation of the impact
on surface of the Saharan dust arrival to the Iberian Peninsula. |
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