Publication Date:
2021-12-22
Description:
Volcanic emissions are a well-known hazard that can have serious impacts on local
populations and aviation operations. Whereas several remote sensing observations detect
high-intensity explosive eruptions, few studies focus on low intensity and long-lasting volcanic
emissions. In this work, we have managed to fully characterize those events by analyzing the volcanic
plume produced on the last day of the 2018 Christmas eruption at Mt. Etna, in Italy. We combined
data from a visible calibrated camera, a multi-wavelength elastic/Raman Lidar system, from SEVIRI
(EUMETSAT-MSG) and MODIS (NASA-Terra/Aqua) satellites and, for the first time, data from an
automatic sun-photometer of the aerosol robotic network (AERONET). Results show that the volcanic
plume height, ranging between 4.5 and 6 km at the source, decreased by about 0.5 km after 25 km.
Moreover, the volcanic plume was detectable by the satellites up to a distance of about 400 km and
contained very fine particles with a mean e ective radius of about 7 m. In some time intervals,
volcanic ash mass concentration values were around the aviation safety thresholds of 2 103 g m3.
Of note, Lidar observations show two main stratifications of about 0.25 km, which were not observed
at the volcanic source. The presence of the double stratification could have important implications
on satellite retrievals, which usually consider only one plume layer. This work gives new details
on the main features of volcanic plumes produced during low intensity and long-lasting volcanic
plume emissions.
Description:
Published
Description:
3866
Description:
5V. Processi eruttivi e post-eruttivi
Description:
JCR Journal
Keywords:
04.08. Volcanology
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Permalink