@misc{10481/31810,
year = {2012},
url = {http://hdl.handle.net/10481/31810},
abstract = {Lidar and sun-photometer measurements were performed intensively over the Iberian Peninsula (IP) during the eruption of the Eyjafjallajökull volcano (Iceland) in April–May 2010. The volcanic plume reached all the IP stations for the first time on 5 May 2010. A thorough study of the event was conducted for the period 5–8 May. Firstly, the spatial and temporal evolution of the plume was described by means of lidar and sun-photometer measurements supported with backtrajectories. The volcanic aerosol layers observed over the IP were rather thin (<1000 m) with a top height up to 11–12 km. However, in some cases at the beginning of the period the thickness of those layers reached several kilometers in Évora and Madrid. The optical thicknesses associated to those layers were rather low (between 0.013 and 0.020 in average over the whole period), with peak values near 0.10 detected on 7 May. Secondly, the volcanic aerosols were characterized in terms of extinction and backscatter coefficients, lidar ratios, Ångström exponents and linear particle depolarization ratio. Lidar ratios at different sites varied between 30 and 50 sr without a marked spectral dependency. Similar extinction-related Ångström exponents varying between 0.6 and 0.8 were observed at different sites. The temporal evolution of the backscatter-related Ångström exponents points out a possible decrease of the volcanic particle size as the plume moved from west to east. Particle depolarization ratios on the order of 0.06–0.08 confirmed the coexistence of both ash and non-ash particles. Additionally, profiles of mass concentration were obtained with a method using the opposite depolarizing effects of ash particles (strongly depolarizing), non-ash particles (very weakly depolarizing), and sun-photometer observations. In Granada the ash mass concentration was found to be approximately 1.5 times higher than that of non-ash particles, and probably did not exceed the value of 200 μg m−3 during the whole event.},
organization = {This work is supported by the 7th Framework
Programme project Aerosols, Clouds, and Trace Gases Research
Infrastructure Network (ACTRIS) (grant agreement no. 262254);
by the MICINN (Spanish Ministry of Science and Innovation)
and FEDER funds under the project TEC2009-09106/TEC and
UNPC10-4E-442, and the Complementary Actions CGL2010-
09225-E and CGL2011-13580-E/CLI; by the Spanish Ministry of
Education under the project PR2011-0358. It has also been supported
by FCT (Fundac˜ao para a Ciˆencia e a Tecnologia) through
the National Re-equipment Program REDE/1527/RNG/2007.
Jana Preißler was funded by FCT (grant SFRH/BD/47521/2008).
Juan Luis Guerrero-Rascado was partially funded by FCT (grant
SFRH/BPD/63090/2009) and by the Spanish Ministry of Education
(grant EX2009-0700).},
publisher = {Copernicus Publications},
keywords = {Measurements},
keywords = {Raman lidar},
keywords = {Mount Pinatubo},
keywords = {Ash},
keywords = {Eruption},
keywords = {Profiles},
keywords = {Dispersion},
title = {Monitoring of the Eyjafjallajökull volcanic aerosol plume over the Iberian Peninsula by means of four EARLINET lidar stations},
doi = {10.5194/acp-12-3115-2012},
author = {Sicard, M. and Guerrero Rascado, Juan Luis and Navas Guzmán, Francisco and Preißler, Jana and Molero, F. and Tomás, S. and Bravo Aranda, Juan Antonio and Comeron, A. and Rocadenbosch, F. and Wagner, Frank and Pujadas, M. and Alados Arboledas, Lucas},
}