Journal cover Journal topic
Atmospheric Measurement Techniques An interactive open-access journal of the European Geosciences Union

Journal metrics

  • IF value: 3.089 IF 3.089
  • IF 5-year<br/> value: 3.700 IF 5-year
    3.700
  • CiteScore<br/> value: 3.59 CiteScore
    3.59
  • SNIP value: 1.273 SNIP 1.273
  • SJR value: 2.026 SJR 2.026
  • IPP value: 3.082 IPP 3.082
  • h5-index value: 45 h5-index 45
Atmos. Meas. Tech., 10, 1-14, 2017
http://www.atmos-meas-tech.net/10/1/2017/
doi:10.5194/amt-10-1-2017
© Author(s) 2017. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
02 Jan 2017
Remote sensing of volcanic CO2, HF, HCl, SO2, and BrO in the downwind plume of Mt. Etna
André Butz1,5,6, Anna Solvejg Dinger2, Nicole Bobrowski2,3, Julian Kostinek1, Lukas Fieber2, Constanze Fischerkeller1, Giovanni Bruno Giuffrida4, Frank Hase1, Friedrich Klappenbach1, Jonas Kuhn2, Peter Lübcke2, Lukas Tirpitz2, and Qiansi Tu1 1IMK-ASF, Karlsruhe Institute of Technology (KIT), Leopoldshafen, Germany
2Institute for Environmental Physics, Heidelberg University, Germany
3Institute of Geosciences, Johannes Gutenberg University Mainz, Germany
4Istituto Nazionale di Geofisica e Vulcanologia, Palermo, Italy
5Institut für Physik der Atmosphäre, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen, Germany
6Meteorologisches Institut, Ludwig-Maximilians-Universität (LMU), München, Germany
Abstract. Remote sensing of the gaseous composition of non-eruptive, passively degassing volcanic plumes can be a tool to gain insight into volcano interior processes. Here, we report on a field study in September 2015 that demonstrates the feasibility of remotely measuring the volcanic enhancements of carbon dioxide (CO2), hydrogen fluoride (HF), hydrogen chloride (HCl), sulfur dioxide (SO2), and bromine monoxide (BrO) in the downwind plume of Mt. Etna using portable and rugged spectroscopic instrumentation. To this end, we operated the Fourier transform spectrometer EM27/SUN for the shortwave-infrared (SWIR) spectral range together with a co-mounted UV spectrometer on a mobile platform in direct-sun view at 5 to 10 km distance from the summit craters. The 3 days reported here cover several plume traverses and a sunrise measurement. For all days, intra-plume HF, HCl, SO2, and BrO vertical column densities (VCDs) were reliably measured exceeding 5  × 1016, 2  × 1017, 5  × 1017, and 1  × 1014 molec cm−2, with an estimated precision of 2.2  × 1015, 1.3  × 1016, 3.6  × 1016, and 1.3  × 1013 molec cm−2, respectively. Given that CO2, unlike the other measured gases, has a large and well-mixed atmospheric background, derivation of volcanic CO2 VCD enhancements (ΔCO2) required compensating for changes in altitude of the observing platform and for background concentration variability. The first challenge was met by simultaneously measuring the overhead oxygen (O2) columns and assuming covariation of O2 and CO2 with altitude. The atmospheric CO2 background was found by identifying background soundings via the co-emitted volcanic gases. The inferred ΔCO2 occasionally exceeded 2  ×  1019 molec cm−2 with an estimated precision of 3.7  ×  1018 molec cm−2 given typical atmospheric background VCDs of 7 to 8  ×  1021 molec cm−2. While the correlations of ΔCO2 with the other measured volcanic gases confirm the detection of volcanic CO2 enhancements, correlations were found of variable significance (R2 ranging between 0.88 and 0.00). The intra-plume VCD ratios ΔCO2 ∕ SO2, SO2 ∕ HF, SO2 ∕ HCl, and SO2 ∕ BrO were in the range 7.1 to 35.4, 5.02 to 21.2, 1.54 to 3.43, and 2.9  ×  103 to 12.5  ×  103, respectively, showing pronounced day-to-day and intra-day variability.

Citation: Butz, A., Dinger, A. S., Bobrowski, N., Kostinek, J., Fieber, L., Fischerkeller, C., Giuffrida, G. B., Hase, F., Klappenbach, F., Kuhn, J., Lübcke, P., Tirpitz, L., and Tu, Q.: Remote sensing of volcanic CO2, HF, HCl, SO2, and BrO in the downwind plume of Mt. Etna, Atmos. Meas. Tech., 10, 1-14, doi:10.5194/amt-10-1-2017, 2017.
Publications Copernicus
Download
Short summary
Remote sensing of the gaseous composition of non-eruptive, passively degassing volcanic plumes can be a tool for volcano monitoring. Here, we report on a field study that demonstrates the feasibility of remotely measuring the volcanic enhancements of carbon dioxide, hydrogen fluoride, hydrogen chloride, sulfur dioxide, and bromine monoxide in the plume of Mt. Etna using portable spectroscopic instrumentation sampling the plume several kilometers downwind of the source.
Remote sensing of the gaseous composition of non-eruptive, passively degassing volcanic plumes...
Share