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| Titel |
Eruption column height: a comparison between ground and satellite measurements |
| VerfasserIn |
Simona Scollo, Michele Prestifilippo, Emilio Pecora, Stefano Corradini, Luca Merucci, Gaetano Spata, Mauro Coltelli |
| Konferenz |
EGU General Assembly 2014
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250090766
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| Publikation (Nr.) |
 EGU/EGU2014-5022.pdf |
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| Zusammenfassung |
| The eruption column height estimation is an essential parameter to evaluate the total mass
eruption rate, the gas and aerosol plume dispersal and retrievals. The column height may be
estimated using different systems (e.g. satellite, aircraft and ground observations) which may
present marked differences. In this work we use the calibrated images collected by the
video-surveillance system of the Istituto Nazionale di Geofisica e Vulcanologia, Osservatorio
Etneo, from the visible camera located in Catania, 27 km from the vent. The analysis
is carried out on twenty lava fountains from the New South East Crater during
the recent Etna explosive activity. Firstly, we calibrated the camera to estimate its
intrinsic parameters and the full camera model. Furthermore, we selected the images
which recorded the maximum phase of the eruptive activity. Hence, we applied an
appropriate correction to take into account the wind effect. The column height was also
evaluated using SEVIRI and MODIS satellite images collected at the same time of the
video camera measurements. The satellite column height retrievals is realized by
comparing the 11 μm brightness temperature of the most opaque plume pixels with the
atmospheric temperature profile measured at Trapani WMO Meteo station (the
nearest WMO station to the Etnean area). The comparison between satellite and
ground data show a good agreement and the column altitudes ranges between 7.5
and 9 km (upper limit of the camera system). For nine events we evaluated also
the thickness of the volcanic plumes in the umbrella region (near the vent) which
ranges between 2 and 3 km. The proposed approach help to quantitatively evaluate
the column height that may be used by volcanic ash dispersal and sedimentation
models for improving forecasts and reducing risks to aviation during volcanic crisis. |
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