Tunable diode laser measurements of hydrothermal/volcanic CO 2 and implications for the global CO 2 budget

Quantifying the CO 2 flux sustained by low-temperature fumarolic fields in hydrothermal/volcanic environments has remained a challenge, to date. Here, we explored the potential of a commercial infrared tunable laser unit for quantifying such fumarolic volcanic/hydrothermal CO 2 fluxes. Our field tes...

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Bibliographic Details
Published in:Solid Earth
Main Authors: M. Pedone, A. Aiuppa, G. Giudice, F. Grassa, V. Francofonte, B. Bergsson, E. Ilyinskaya
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2014
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Online Access:https://doi.org/10.5194/se-5-1209-2014
https://doaj.org/article/1e242d6148ec41f58abbc04beb44ef80
Description
Summary:Quantifying the CO 2 flux sustained by low-temperature fumarolic fields in hydrothermal/volcanic environments has remained a challenge, to date. Here, we explored the potential of a commercial infrared tunable laser unit for quantifying such fumarolic volcanic/hydrothermal CO 2 fluxes. Our field tests were conducted between April 2013 and March 2014 at Nea Kameni (Santorini, Greece), Hekla and Krýsuvík (Iceland) and Vulcano (Aeolian Islands, Italy). At these sites, the tunable laser was used to measure the path-integrated CO 2 mixing ratios along cross sections of the fumaroles' atmospheric plumes. By using a tomographic post-processing routine, we then obtained, for each manifestation, the contour maps of CO 2 mixing ratios in the plumes and, from their integration, the CO 2 fluxes. The calculated CO 2 fluxes range from low (5.7 ± 0.9 t d −1 Krýsuvík) to moderate (524 ± 108 t d −1 La Fossa crater, Vulcano). Overall, we suggest that the cumulative CO 2 contribution from weakly degassing volcanoes in the hydrothermal stage of activity may be significant at the global scale.