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Eruptive and diffuse emissions of CO2 from Mount Etna

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Abstract

MOUNT Etna, in Sicily, is one of the world's most actively degassing volcanoes1. Here we use data collected from 1975 to 1987 to estimate carbon dioxide emissions from the summit craters and the upper flanks of the volcano. By combining measurements of the SO2 flux in the plume (refs 1–6 and this paper) with measurements of the CO2/SO2 ratio of the plume gases, we find that the average output of CO2 from summit crater degassing is 13±3 Tg yr−1. This is an order of magnitude higher than the annual CO2 output from Kilauea7,8, Hawaii, and representative arc volcanoes9,10. Furthermore, we find that diffuse emissions of CO2 from the upper flanks of Etna are magma-derived and are of a similar magnitude to those emitted from the crater plume. This observation, as well as others11–14, verifies the idea15 that extensive diffuse release of magmatic CO2 may occur in volcanically active regions—a process that needs to be taken into account when evaluating the volatile budget of subaerial volcanism. Such degassing may be of use for monitoring volcanic activity, could provide a means for radiocarbon dating of eruptions, and may be a mechanism by which CO2 is injected into crater lakes.
© 1991Nature Publishing Group
© 1991Nature Publishing Group
© 1991Nature Publishing Group
© 1991Nature Publishing Group
© 1991Nature Publishing Group
... El hecho de que los gases disueltos en el magma son los que proporcionan la fuerza motriz de las erupciones volcánicas, ha permitido que en la actualidad el estudio y seguimiento de la composición química e isotópica de los gases volcánicos así como de sus emisiones a la atmósfera sean un instrumento muy útil para la monitorización y vigilancia de la actividad volcánica (Matsuo, 1960;Matsuo et al., 1975;Casadevall et al., 1983;Hirabayashi et al., 1986;Sato, 1988;Symonds et al., 1990;Sano et al., 1991;Casadevall et al., 1994;Giggenbach, 1996;Chiodini et al., 1998;McGee & Gerlach, 1998;Hernández et al., 2001a;Carapezza et al., 2004;Pérez et al., 2006;Gurrieri et al., 2008;Rizzo et al., 2009). Durante las dos últimas décadas, los estudios de emisión difusa de CO 2 por los volcanes han sido numerosos, poniendo de manifiesto la importancia de esta metodología para evaluar la dinámica de desgasificación de los volcanes y su relación con la actividad volcánica (Carbonelle et al., 1985;Allard et al., 1987Allard et al., , 1991Baubron et al., 1990Baubron et al., , 1991Pérez, 1992;Farrar et al., 1995;Giammanco et al., 1995;Chiodini et al., 1996;Pérez et al., 1996Pérez et al., , 2004Pérez et al., , 2006Hernández et al., 1998Hernández et al., , 2001bSalazar et al., 2001Salazar et al., , 2003Melián et al., 2004;Granieri et al., 2006;Lecinsky et al., 2007;Padrón et al., 2008;Rizzo et al., 2009). ...
... La mayoría de los estudios realizados en el ámbito de desgasificación difusa hacen referencia al CO 2 por ser la segunda especie mayoritaria de los gases volcánicos después del vapor de agua y por su baja solubilidad en fundidos silicatados (Gerlach & Graeber, 1985) así como por la facilidad para ser medido in situ (Allard et al., 1987(Allard et al., , 1991Baubron et al., 1991;Pérez, 1992;Farrar et al., 1995;Giammanco et al., 1995;Pérez et al., 1996Pérez et al., , 2004Pérez et al., , 2006Hernández et al., 1998Hernández et al., , 2001aHernández et al., , 2001bHernández et al., , 2003Hernández et al., , 2006Salazar et al., 2001Salazar et al., , 2003Cardellini et al, 2003;Frondini et al., 2004;Melián et al., 2004;Notsu et al., 2005;Padrón et al., 2008). ...
... Los valores obtenidos de flujo de CO 2 mediante el estudio de desgasificación difusa fueron superiores a los obtenidos en las emisiones visibles del Poás (423 ± 54 t d -1 y 542 ± 63 t d -1 para 2001 y 2003, respectivamente). En otros sistemas volcánicos como Masaya, Nicaragua (Pérez et al., 2000), Vulcano, Italia (Baubron et al., 1990;Chiodini et al., 1998;Italiano et al., 1998) o Etna, Italia, (Allard et al., 1991) se han realizado comparaciones entre las emisiones visibles y difusas de CO 2 . Pérez et al. (2000) encontró que la relación desgasificación difusa/pluma para las emisiones de CO 2 en el volcán Masaya, Nicaragua, es del orden de 9. El estudio realizado en Vulcano, Italia, puso de manifiesto la importante cantidad de CO 2 emitida por este sistema volcánico de forma difusa y que se estima tres veces superior a la emisión del cráter en forma visible (Baubron et al., 1990;Chiodini et al., 1998;Italiano et al., 1998). ...
... Most studies focused on the environmental and climatic impacts and the associated risks of large eruptions (e.g. Robock, 1981;Kelly and Sear, 1984;Allard et al., 1991;Hansen et al., 1992;Self et al., 1993;McCormick et al., 1995;Robock, 2000;Oppenheimer, 2003;Textor et al., 2003;Robock, 2004;Self et al., 2004;Self, 2005;Horwell and Baxter, 2006;Self, 2006;von Glasow et al., 2009;Gerlach, 2011;Raible et al., 2016), whereas little is known about the fate of gases emitted during the long-lasting non-eruptive periods and hydrothermal activity. Recent studies have shown that volcanoes emit to the atmosphere a huge amount of volatiles even during quiescent periods (Baubron et al., 1990;Allard et al., 1991;Delmelle et al., 2002;Mӧrner and Etiope, 2002). ...
... Robock, 1981;Kelly and Sear, 1984;Allard et al., 1991;Hansen et al., 1992;Self et al., 1993;McCormick et al., 1995;Robock, 2000;Oppenheimer, 2003;Textor et al., 2003;Robock, 2004;Self et al., 2004;Self, 2005;Horwell and Baxter, 2006;Self, 2006;von Glasow et al., 2009;Gerlach, 2011;Raible et al., 2016), whereas little is known about the fate of gases emitted during the long-lasting non-eruptive periods and hydrothermal activity. Recent studies have shown that volcanoes emit to the atmosphere a huge amount of volatiles even during quiescent periods (Baubron et al., 1990;Allard et al., 1991;Delmelle et al., 2002;Mӧrner and Etiope, 2002). For instance, Mount Etna (Sicily, South Italy) emits about 21 × 10 9 g day − 1 of TV (Total Volatile) (Aiuppa et al., 2008); Stromboli Island (Aeolian Islands, South Italy) 6-12 × 10 9 g day − 1 (Allard et al., 1994) and the volcano Masaya (Nicaragua) 14-16 × 10 9 g day − 1 (Burton et al., 2000;Martin et al., 2010;Girona et al., 2014). ...
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Volcanoes are currently to be regarded as natural sources of air pollutants. Climatic and environmental forcing of large volcanic eruptions are well known, although gases emitted through passive degassing during periods of quiescence or hydrothermal activity can also be highly dangerous for the environment and public health. Based on compositional and isotopic data, a survey on the spatial distribution in air of the main volatile compounds of carbon (CO2 and CH4) and sulfur (H2S and SO2) emitted from the fumarolic field of Pisciarelli (Campi Flegrei, Pozzuoli, Naples), a hydrothermal area where degassing activity has visibly increased since 2009, was carried out. The main goals of this study were (i) to evaluate the impact on air quality of these natural manifestations and (ii) inquire into the behavior of the selected chemical species once released in air, and their possible use as tracers to distinguish natural and anthropogenic sources. Keeling plot analysis of CO2 and CH4 isotopes revealed that the hydrothermal area acts as a net source of CO2 in air, whilst CH4 originated mainly from anthropogenic sources. Approaching the urban area, anthropogenic sources of CO2 increased and, at distances greater than 800 m from the Pisciarelli field, they prevailed over the hydrothermal signal. While hydrothermal CO2 simply mixed with that in the atmospheric background, H2S was possibly affected by oxidation processes. Therefore, SO2 measured in the air near the hydrothermal emissions had a secondary origin, i.e. generated by oxidation of hydrothermal H2S. Anthropogenic SO2 was recognized only in the furthest measurement site from Pisciarelli. Finally, in the proximity of a geothermal well, whose drilling was in progress during our field campaign, the H2S concentrations have reached values up to 3 orders of magnitude higher than the urban background, claiming the attention of the local authorities.
... The process of diffuse soil degassing from tectonic zones is anomalous and occurs over a long period of time. The amount of CO 2 emitted from the volcanoes depends on the volcanic activity (Allard et al., 1991;Badalamenti et al., 1991;Andres et al., 1991;Valenza, 1994;Capasso et al., 1999;Wallace, 2001;Shimoike et al., 2002;Aiuppa et al., 2007Aiuppa et al., , 2019Shinohara, 2008;Granieri et al., 2009;Viveiros et al., 2010;Camarda et al., 2012Camarda et al., , 2019Di Martino et al., 2013, 2021De Gregorio and Camarda, 2016;Fischer et al., 2019). The monitoring of CO 2 flux served as tools to achieve volcanic risk mitigation. ...
... The monitoring of CO 2 flux served as tools to achieve volcanic risk mitigation. It is a challenge for the scientific community to understand the impact of Earth's outgassing process on atmospheric chemistry (Allard et al., 1991;Hernández et al., 2001;Frondini et al., 2004;Caliro et al., 2005;Werner et al., 2008Werner et al., , 2014Bennati et al., 2011;Carapezza et al., 2011;Di Martino et al., 2013, 2016a, 2016b, 2021Granieri et al., 2014Granieri et al., , 2016bZhang et al., 2017;Camarda et al., 2019;Inguaggiato et al., 2020). ...
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... Les mesures réalisées sur le terrain présentent de nombreuses limites mal prises en compte dans les modèles prédictifs, telles que : (i) les différences de biomes et de sols entre les différentes régions où se trouve le permafrost , (ii) la faible couverture tant spatiale que temporelle des mesures de flux de gaz à la surface du permafrost qui rend incertaines les extrapolations réalisées à partir de ces mesures (Masyagina et Menyailo, 2020). De plus, il est difficile de déterminer si les augmentations de flux sont dues à l'augmentation de la température, à la stimulation de l'activité microbienne (Schuur et al., 2015 ;Adamczyk et al., 2019) ou à des variations de teneur en eau dans les sols en raison de la fonte de la glace (Masyagina et Menyailo, 2020 (Allard et al., 1991). ...
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... Les mesures réalisées sur le terrain présentent de nombreuses limites mal prises en compte dans les modèles prédictifs, telles que : (i) les différences de biomes et de sols entre les différentes régions où se trouve le permafrost , (ii) la faible couverture tant spatiale que temporelle des mesures de flux de gaz à la surface du permafrost qui rend incertaines les extrapolations réalisées à partir de ces mesures (Masyagina et Menyailo, 2020). De plus, il est difficile de déterminer si les augmentations de flux sont dues à l'augmentation de la température, à la stimulation de l'activité microbienne (Schuur et al., 2015 ;Adamczyk et al., 2019) ou à des variations de teneur en eau dans les sols en raison de la fonte de la glace (Masyagina et Menyailo, 2020 (Allard et al., 1991). ...
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