title: Optical remote sensing measurements of bromine and  sulphur emissions: Investigating their potential as tracers of  volcanic activity
creator: Lübcke, Peter
subject: ddc-530
subject: 530 Physics
description: The optical remote sensing of volcanic gas emissions has become an established field in recent decades. The total amount of gas emissions (quantified by measuring the SO2  emission rate) as well as the composition of gases, can help researchers to understand volcanic systems. This knowledge is needed to improve forecasts of volcanic eruptions. For this thesis, volcanic gas emissions were investigated with two different techniques  on different time scales. First, high time-resolution (order of 1 s) 2D-SO2 column density images measured by an SO2 camera were used to quantify SO2 emission rates at  Popocatépetl, Mexico, and Stromboli, Italy. The frequency of the flux was investigated with a wavelet analysis. It was verified that calibrating the SO2 camera with help of  a DOAS system leads to more robust results than using calibration cells, especially for a volcanic plume containing ash or aerosols. Second, spectra from the scanning DOAS network NOVAC (with a time resolution of ≈ 5 – 15 minutes) were evaluated for BrO/SO2 ratios. It was shown that data from NOVAC actually has sufficient quality  to evaluate spectra for BrO. An automatic evaluation algorithm was developed and used to create a four-year time series (2009 – 2013) of BrO/SO2 ratios at Nevado del  Ruiz, Colombia. The BrO/SO2 ratio showed variations that are closely correlated to the level of volcanic activity indicating its usefulness as an additional volcanological  parameter. Several possibilities for further improving data quality were investigated. This included temperature effects on the DOAS retrieval, the influence of radiative  transfer and problems arising from reference spectra contaminated with SO2.
date: 2014
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/16879/1/Dissertation_Peter_L%C3%BCbcke.pdf
identifier: DOI:10.11588/heidok.00016879
identifier: urn:nbn:de:bsz:16-heidok-168796
identifier:   Lübcke, Peter  (2014) Optical remote sensing measurements of bromine and sulphur emissions: Investigating their potential as tracers of volcanic activity.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/16879/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng