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| Titel |
Aircraft in situ and remote sensing measurements of emissions from Etna volcano, Sicily |
| VerfasserIn |
A. Vogel, K. Weber, C. Fischer, A. J. Prata, A. J. Durant |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250070491
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| Zusammenfassung |
| Volcanoes emit particles (silicates and sulphate aerosol) and gases (e.g., water and sulphur
dioxide) which influence the radiative balance of the atmosphere. The rate at which
sulphur dioxide oxidises to sulphate aerosol is poorly constrained and measurements
of downwind abundance are required to quantify the rate at which this process
occurs.
During July and November 2011, a series of measurements were performed in emissions
from Etna Volcano, Sicily, using the University of Applied Sciences (Dusseldorf) research
aircraft. Both in situ and remote sensing instrumentation was simultaneously deployed to
quantify the down-wind characteristics of gases and particles in the plume emitted by the
volcano. In situ particle characteristics were measured using a Grimm 1.109 optical particle
counter (microparticles 0.25-32 microns) and Grimm 1320 diffusion electrometer
(nanoparticles 25-300 nanometers). Column abundance of sulphur dioxide was
measured using a vertically-pointing differential optical absorption spectrometer
(DOAS). These measurements were compared to horizontal pathlength-integrated
measurements of sulphur dioxide from the Airborne Volcanic Imaging Object Detector
(AVOID).
Down-wind plume dispersion was discriminated through a series of aircraft transects
below and through the volcanic plume. The emissions contained large amounts of
nanoparticles relative to microparticles, which reflects gas-phase nucleation of sulphate
aerosol. The AVOID system discriminated horizontal layering of volcanic aerosol at altitudes
of up to 12,000 ft from a detection range of >50 km. Plume boundaries were discriminated
using a combination of the in situ and DOAS measurements in order to compare to the
pathlength-integrated measurements from AVOID. |
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