Volcanic Emissions, Plume Dispersion and Downwind Radiative Impacts following Mount Etna Series of Eruptions of 21-26 February 2021

Abstract. Excessive numerical diffusion is one of the major limitations in the representation of long-range transport by chemistry transport models. In the present study, we focus on excessive diffusion in the vertical direction, which has been shown to be a major issue, and we explore three possible ways of addressing this problem: increasing the vertical resolution, using an advection scheme with anti-diffusive properties and more accurately representing the vertical wind. This study was carried out using the CHIMERE chemistry transport model for the 18 March 2012 eruption of Mount Etna, which released about 3 kt of sulfur dioxide into the atmosphere in a plume that was observed by satellite instruments (the Infrared Atmospheric Sounding Interferometer instrument, IASI, and the Ozone Monitoring Instrument, OMI) for several days. The change from the classical Van Leer (1977) scheme to the Després and Lagoutière (1999) anti-diffusive scheme in the vertical direction was shown to provide the largest improvement to model outputs in terms of preserving the thin plume emitted by the volcano. To a lesser extent, the improved representation of the vertical wind field was also shown to reduce plume dispersion. Both of these changes helped to reduce vertical diffusion in the model as much as a brute-force approach (increasing vertical resolution).

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Near crater observations of gas and aerosols variability at Mount Etna during the EPL-RADIO and EPL-REFLECT measurement campaigns.

10.5194/egusphere-egu21-5684 ◽

2021 ◽

Author(s):

Suzanne Crumeyrolle ◽

Marion Ranaivombola ◽

Tjarda Roberts ◽

Chiara Giorio ◽

Giusseppe Salerno ◽

...

Keyword(s):

Low Cost ◽

Health Hazard ◽

Regional Climate ◽

Chemical Properties ◽

Inorganic Ions ◽

Mount Etna ◽

Volcanic Plume ◽

Local Health ◽

Volcanic Emissions ◽

Short Period

During the EPL (Etna Plume Lab) campaigns occurring in 2017 (EPL-RADIO) and 2019 (EPL-REFLECT),&#160; gas&#160; and aerosol measurements were performed&#160; at Mount Etna (Sicily, Italy) to better assess the role of volcanic aerosols on both regional climate system and local health hazard. Gas related to volcanic emissions (such as SO2, H2S and others) were measured with low cost sensors (Alphasense) and HCl/SO2 ratio was validated in comparison to FTIR measurements. Aerosol physical and chemical properties were measured using low-cost Optical Particle Counters (OPCN2 from Alphasense) and filter measurements dedicated to organic acids, inorganic ions, soluble metals and total metals. During the EPL-REFLECT campaign, in-situ measurements were performed during: 1) the hike up, 2) a 2-hours period in the close vicinity of the Bocca Nuova crater, 3) the hike down and 4) in Milo (city on the flank of the Etna). Moreover, few OPCs were left unattended at the Bocca Nuova crater for two full days.&#160;&#160;Gas abundances at the crater-rim ranged from a few to 10&#8217;s ppmv SO2, with correlation to PM. The analysis of the 2 days measurements highlights a clear diurnal variation of aerosol size distributions. Indeed, at sunrise the total number and mass concentration is rapidly increasing from 15mg/m3 to 125mg/m3 in less than 2 hours. The variation of PM1/PM10 ratio shows a constant trend throughout the day except during a short period of time associated with high wind speeds. These results suggest that most aerosols are emitted through degassing and conversion of precursor gases to particles.Moreover, analysis of aerosol samples collected on filters showed a change in metal solubility from the samples collected at the crater and the samples collected after atmospheric transport in Milo. This may indicate that the volcanic plume underwent processing in the aqueous phase during transport.

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Three-dimensional distribution of Mount Etna’s emissions during the EPL-REFLECT campaign in July 2019

10.5194/egusphere-egu21-10664 ◽

2021 ◽

Author(s):

Alessia Sannino ◽

Antonella Boselli ◽

Giuseppe Leto ◽

Simona Scollo ◽

Ricardo Zanmar Sanchez ◽

...

Keyword(s):

Source Parameters ◽

Three Dimensional ◽

Mount Etna ◽

Atmospheric Composition ◽

Laser Source ◽

Plume Dispersion ◽

Essential Point ◽

Field Campaign ◽

Radiative Balance ◽

Volcanic Aerosols

Mount Etna (Italy) is the most high-impact volcanoes on Mediterranean scale mainly due to its eruptive activity and continuous passive degassing, and the inherent large amount of effluents released into the atmosphere. Mount Etna&#8217;s emission mainly originate from the summit craters at an altitude of about 3300&#160;m, feeding frequently volcanic gases and aerosols into the free troposphere. Consequently, their effects on the atmosphere and regional climate system span over relatively long spatiotemporal scales.In order to better understand the role that Mount Etna&#8217;s emissions play on the atmospheric composition and radiative balance in the Mediterranean area, multidisciplinary and multi-scale studies have been carried out since a few years within the different phases of the EtnaPlumeLab (EPL) research cluster. A part of the EPL effort is based on dedicated field campaigns, that aim at the characterization of volcanic sources emissions and nears-source plume dispersion and evolution.In this work, we investigate the three-dimensional (3D) distribution of the volcanic aerosols from Mount Etna observed during the most recent EPL field campaign, named EPL-REFLECT (near-source estimations of Radiative EFfects of voLcanic aErosols for Climate and air quality sTudies) carried out within the Transnational Access component of the EUROVOLC project. This field campaign completes the previous EPL-RADIO (Radioactive Aerosols and other source parameters for better atmospheric Dispersion and Impact estimatiOns) campaign. Here we discuss the observations of a multiparametric LiDAR system AMPLE. The LiDAR is equipped with a fast scanning, double depolarization (at 532 and 355 nm) and high repetition laser source (1kHz), which is an essential point to derive time series of 3D-resolved aerosol properties near Etna. During the 8-12th of July 2019 period, day/night LiDAR measurements were performed by AMPLE from the astronomical observatory of the INAF-Catania in the location of Serra la Nave at 1725 m a.s.l., pointing towards the summit of Mount Etna. In particular, on the July 11th, the scan was performed with time-steps of 15 minutes at different angles from the top of the volcano to the zenith. These acquisitions highlight the atmospheric evolution of two layers related to two distinct degassing episodes. A comparative analysis with wind speed information and the integration with complementary photometric ground measurements have further constrained this 3D characterization and the evolution of these layers, including those outside the LiDAR field of view.

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The multi oxygen isotope analyses on black crust from Sicily highlight the volcanic emission influence from Mount Etna on urban areas

10.5194/egusphere-egu2020-20136 ◽

2020 ◽

Author(s):

Adeline Aroskay ◽

Erwan Martin ◽

Slimane Bekki ◽

Giuseppe Montana ◽

Luciana Randazzo ◽

...

Keyword(s):

Oxygen Isotopes ◽

Urban Areas ◽

Ice Cores ◽

Mount Etna ◽

Black Crust ◽

Volcanic Emissions ◽

Average Value ◽

Black Crusts ◽

Sulphate Aerosols ◽

Isotope Analyses

This study reports on measurements of &#916;17O (derived from the triple oxygen isotopes) in sulphate from black crust sampled in Sicily. Atmospheric oxidants, such as O3, H2O2, OH and O2 carry specific 17O-anomalies, which are partly transferred to the sulphate during sulphur gas (e.g. SO2) oxidation. Hence, the &#916;17O in sulphate can be used as a tracer of sulphur oxidation pathways. So far, this method has been mostly applied on sulphate from aerosols, rainwaters, volcanic deposits and ice cores. Here we propose a new approach, that aims to investigate the dominant oxidants of gaseous sulphur precursors into sulphate extracted from black crust material. Black crusts are mostly found on building/monument/sculpture and are the result of the reaction between sulphur compounds (SO2, H2SO4) and carbonate (CaCO3) from the substrate, which leads to the formation of gypsum (CaSO4, 2H2O). Sicilian black crust from sites under different emission influences (anthropogenic, marine and volcanic) were collected. Multi oxygen and sulphur isotope analyses were performed to better assess the origins of black crust sulphate in these different environments. This is crucial for both a better understanding of the sulphur cycle and the preservation of historical monument.Multi sulphur isotopes show mostly negative values ranging from -0.4 &#8240; to 0.02 &#8240; &#177; 0.01 and from -0.59 &#8240; to 0.41&#8240; &#177; 0.3 for &#916;33S and &#916;36S respectively. This is unique for natural samples and different from sulphate aerosols measured around the world (&#916;33S > 0&#8240;). This tends to indicate that sulphate from black crust is not generated by the same processes as sulphate aerosols in the atmosphere. Instead of SO2 oxidation in the atmosphere, dry deposition of SO2 and its oxidation on the substratum is preferred. The multi oxygen isotopes show a clear dependence with the geographical repartition of the samples. Indeed, black crusts from Palermo (the biggest Sicilian city) show small 17O-anomalies ranging between -0.16 &#8240; to 1.02 &#8240; with an average value of 0.45 &#8240; &#177; 0.26 (n=12; 2&#963;). This is consistent with &#916;17O values measured in black crust from the Parisian Basin (Genot et al., 2020), which are also formed in an environment influenced by anthropogenic and marine emissions. On the other hand, samples from the eastern part of the Mount Etna region, which are downwind of the volcanic emissions, show the highest 17O-anomalies ranging from 0.48 &#8240; to 3.87 &#8240; with an average value of 2.7 &#8240; &#177; 0.6 (n=11; 2&#963;).These results indicate that volcanic emissions influence the oxygen isotopic signature of black crust sulphate. In standard urban areas, SO2 deposited on the substratum is mostly oxidised by O2-TMI and H2O2 to generate the black crust. Yet, under the influence of volcanic emissions, O3 may play the main role in the SO2 oxidation.

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Recommendations and Protocols for the Use of the Isotope Ratio Infrared Spectrometer (Delta Ray) to Measure Stable Isotopes from CO2: An Application to Volcanic Emissions at Mount Etna and Stromboli (Sicily, Italy)

Geofluids ◽

10.1155/2020/4598190 ◽

2020 ◽

Vol 2020 ◽

pp. 1-21

Author(s):

G. Boudoire ◽

F. Grassa ◽

G. Giuffrida ◽

M. Liuzzo

Keyword(s):

Calibration Procedure ◽

Isotopic Signature ◽

Mount Etna ◽

Volcanic Emissions ◽

Gaseous Species ◽

Internal Calibration ◽

Important Target ◽

Infrared Spectrometer ◽

Isotope Measurements

Among major volatiles released from the Earth’s interior, CO2 is an important target for the international community. The interest is keenly motivated by the contribution of CO2 in the Earth’s carbon budget and its role on past, current, and future climate dynamics. In particular, the isotopic signature of CO2 is fundamental to characterize the source of this gas and its evolution up to the atmosphere. The recent development of new laser-based techniques has marked an important milestone for the scientific community by favoring both high-frequency and in situ stable isotope measurements. Among them, the Delta Ray IRIS (Thermo Scientific Inc., Waltham, USA) is one of the most promising instruments thanks to its high precision, its limited interferences with other gaseous species (such as H2S and/or SO2), and its internal calibration procedure. These characteristics and the relative easiness to transport the Delta Ray IRIS have encouraged its use on the field to analyze volcanic CO2 emissions in recent years but often with distinct customized protocols of measurements. In this study, various tests in the laboratory and on the field have been performed to study the dependence of CO2 isotope measurements on analytical, instrumental, and environmental conditions. We emphasize the exceptional ability of the Delta Ray IRIS to perform isotope measurements for a large range of CO2 concentration (200 ppm–100%) thanks to a dilution system and to get a reliable estimation of the real CO2 content from the diluted one. These tests lead to point out major recommendations on the use of Delta Ray IRIS and allow the development of adapted protocols to analyze CO2 emissions like in volcanic environments.

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New strategies for vertical transport in chemistry-transport models: application to the case of the Mount Etna eruption on March 18, 2012 with CHIMERE v2017r4

10.5194/gmd-2020-62 ◽

2020 ◽

Author(s):

Mathieu Lachatre ◽

Sylvain Mailler ◽

Laurent Menut ◽

Solène Turquety ◽

Pasquale Sellitto ◽

...

Keyword(s):

Transport Model ◽

Vertical Direction ◽

Vertical Wind ◽

Mount Etna ◽

Plume Dispersion ◽

Vertical Resolution ◽

Vertical Diffusion ◽

Transport Models ◽

Range Transport ◽

Brute Force Approach

Abstract. Excessive numerical diffusion is one of the major limitations in the representation of long-range transport by chemistry-transport models. In the present study, we focus on excessive diffusion in the vertical direction, which has been shown to be a major issue, and we explore three possible ways to address this problem: increase vertical resolution, use an advection scheme with antidiffusive properties, and represent more accurately the vertical wind. This study is done with the CHIMERE chemistry-transport model, for the March 18, 2012 eruption of Mount Etna, which has released about 3 kt of sulphur dioxide in the atmosphere into a plume that has been observed by satellite instruments (IASI and OMI) for several days. The change from the classical Van Leer et al., (1977) scheme to the Després and Lagoutière (1999) antidiffusive scheme in the vertical direction has been shown to bring the largest improvement to model outputs in terms of preserving the thin plume emitted by the volcano. To a lesser extent, improved representation of the vertical wind field has also been shown to reduce plume dispersion. Both these changes help reducing vertical diffusion in the model as much as a brute-force approach (increasing vertical resolution).

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Evaluation of the environmental impact of volcanic emissions from the chemistry of rainwater: Mount Etna area (Sicily)

Applied Geochemistry ◽

10.1016/s0883-2927(00)00075-5 ◽

2001 ◽

Vol 16 (7-8) ◽

pp. 985-1000 ◽

Cited By ~ 29

Author(s):

A Aiuppa ◽

P Bonfanti ◽

L Brusca ◽

W D’Alessandro ◽

C Federico ◽

...

Keyword(s):

Environmental Impact ◽

Mount Etna ◽

Volcanic Emissions

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Pillows and hyaloclastites associated to subaerial lavas at the South-West of the base of Mount Etna (Sicily, Italy)

Géologie Méditerranéenne ◽

10.3406/geolm.1975.953 ◽

1975 ◽

Vol 2 (4) ◽

pp. 179-183 ◽

Cited By ~ 5

Author(s):

Guy Kieffer

Keyword(s):

Mount Etna ◽

The South ◽

South West

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On the use of plume models to estimate the flux in volcanic gas plumes

Nature Communications ◽

10.1038/s41467-021-22159-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Julia Woitischek ◽

Nicola Mingotti ◽

Marie Edmonds ◽

Andrew W. Woods

Keyword(s):

Electrochemical Sensors ◽

Measurement Techniques ◽

Flux Measurement ◽

Hydrothermal Systems ◽

Mount Etna ◽

Volcanic Gas ◽

Gas Flux ◽

Convective Structures ◽

Video Images ◽

Villarrica Volcano

AbstractMany of the standard volcanic gas flux measurement approaches involve absorption spectroscopy in combination with wind speed measurements. Here, we present a new method using video images of volcanic plumes to measure the speed of convective structures combined with classical plume theory to estimate volcanic fluxes. We apply the method to a nearly vertical gas plume at Villarrica Volcano, Chile, and a wind-blown gas plume at Mount Etna, Italy. Our estimates of the gas fluxes are consistent in magnitude with previous reported fluxes obtained by spectroscopy and electrochemical sensors for these volcanoes. Compared to conventional gas flux measurement techniques focusing on SO2, our new model also has the potential to be used for sulfur-poor plumes in hydrothermal systems because it estimates the H2O flux.

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The Environmental Effects of the April 2020 Wildfires and the Cs-137 Re-Suspension in the Chernobyl Exclusion Zone: A Multi-Hazard Threat

Atmosphere ◽

10.3390/atmos12040467 ◽

2021 ◽

Vol 12 (4) ◽

pp. 467

Author(s):

Rocío Baró ◽

Christian Maurer ◽

Jerome Brioude ◽

Delia Arnold ◽

Marcus Hirtl

Keyword(s):

Air Quality ◽

Nuclear Power ◽

Transport Model ◽

Atmospheric Transport ◽

Point Of View ◽

Plume Dispersion ◽

Exclusion Zone ◽

Fire Plume ◽

Mean Values ◽

The Impact

This paper demonstrates the environmental impacts of the wildfires occurring at the beginning of April 2020 in and around the highly contaminated Chernobyl Exclusion Zone (CEZ). Due to the critical fire location, concerns arose about secondary radioactive contamination potentially spreading over Europe. The impact of the fire was assessed through the evaluation of fire plume dispersion and re-suspension of the radionuclide Cs-137, whereas, to assess the smoke plume effect, a WRF-Chem simulation was performed and compared to Tropospheric Monitoring Instrument (TROPOMI) satellite columns. The results show agreement of the simulated black carbon and carbon monoxide plumes with the plumes as observed by TROPOMI, where pollutants were also transported to Belarus. From an air quality and health perspective, the wildfires caused extremely bad air quality over Kiev, where the WRF-Chem model simulated mean values of PM2.5 up to 300 µg/m3 (during the first fire outbreak) over CEZ. The re-suspension of Cs-137 was assessed by a Bayesian inverse modelling approach using FLEXPART as the atmospheric transport model and Ukraine observations, yielding a total release of 600 ± 200 GBq. The increase in both smoke and Cs-137 emissions was only well correlated on the 9 April, likely related to a shift of the focus area of the fires. From a radiological point of view even the highest Cs-137 values (average measured or modelled air concentrations and modelled deposition) at the measurement site closest to the Chernobyl Nuclear Power Plant, i.e., Kiev, posed no health risk.

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