Studies of Volcanic Plumes with Remote Spectroscopic Sensing Techniques -DOAS and FTIR measurements on volcanoes of the Network for Observation of Volcanic and Atmospheric Change-
Doktorsavhandling, 2014

Volcanism is a rich geodynamical process, closely linked to the origin and ongoing evolution of the lithosphere, atmosphere, hydrosphere and biosphere. Humans have benefited from the resources provided by volcanoes but also been threatened by the dangers of volcanic eruptions, which accurate prediction remains elusive. This is partly due to the inherent complexity of volcanic systems and partly because of the difficulty of conducting key observations to characterize them. In particular, since the segregation and escape of magmatic volatiles are essential mechanisms behind volcanic eruptions, monitoring the intensity and composition of the resulting emissions in the atmosphere is essential to characterize the state of volcanic activity; however, their direct measurement is not always feasible. Remote spectroscopic sensing, whereby gas species can be quantified by their spectral signatures in electromagnetic radiation gathered at a prudent distance from the plume, offers the possibility to conduct reliable and sustainable monitoring of volcanic emissions. To expand the remote sensing capabilities of volcanological observatories the Network for Observation of Volcanic and Atmospheric Change (NOVAC) was established in 2005. The central theme of this thesis is the acquisition, analysis and interpretation of measurements of volcanic gas emissions on volcanoes of NOVAC. Measurements of the mass flow rate of SO2 and the molar ratios of SO2 against BrO and HCl were obtained by scanning-Differential Optical Absorption Spectroscopy (DOAS) of scattered solar ultraviolet radiation and by Fourier-Transform Spectroscopy (FTIR) of direct solar infrared radiation. The uncertainty of the measurements is characterized and methods for combining observations from different sensors implemented. Statistical and physical models of degassing are proposed for selected volcanoes of the network. The resulting time-series of emission on 16 volcanoes is one of the more detailed compilations of volcanic degassing in the last decade, particularly from passive emissions which are difficult to detect from satellite platforms. This work aims at advancing our knowledge of volcanic eruptions for a better mitigation of their risks.

FTIR

Remote Sensing

DOAS

NOVAC

Volcanic gas emissions

ED-salen, Hörsalsvägen 11, Chalmers tekniska högskola, Göteborg
Opponent: Dr. rer. nat. Konradin Weber, University of Applied Sciences i Düsseldorf, Tyskland

Författare

Santiago Arellano

Chalmers, Rymd- och geovetenskap, Optisk fjärranalys

Network for Observation of Volcanic and Atmospheric Change (NOVAC)-A global network for volcanic gas monitoring: Network layout and instrument description

Journal of Geophysical Research,; Vol. 115(2010)p. Art. no. D05304-

Artikel i vetenskaplig tidskrift

Degassing patterns of Tungurahua volcano (Ecuador) during the 1999–2006 eruptive period, inferred from remote spectroscopic measurements of SO2 emissions

Journal of Volcanology and Geothermal Research,; Vol. 176(2008)p. 151-162

Artikel i vetenskaplig tidskrift

Ämneskategorier

Fjärranalysteknik

Analytisk kemi

Atom- och molekylfysik och optik

Geofysik

Geokemi

Miljövetenskap

Multidisciplinär geovetenskap

Fundament

Grundläggande vetenskaper

ISBN

978-91-7597-070-7

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 3751

ED-salen, Hörsalsvägen 11, Chalmers tekniska högskola, Göteborg

Opponent: Dr. rer. nat. Konradin Weber, University of Applied Sciences i Düsseldorf, Tyskland