title: Spectroscopic Measurements of Atmospheric Trace Gases on Long-Distance Flights
creator: Dix, Barbara
subject: ddc-530
subject: 530 Physics
description: In this thesis results of spectroscopic measurements of atmospheric trace gases on long-distance flights are presented. Nitrogen dioxide (NO2), bromine oxide (BrO), ozone (O3), formaldehyde (HCHO) and nitrous acid (HONO) are detected in scattered light spectra by means of Differential Optical Absorption Spectroscopy (DOAS). The underlying scientific scope is to gain information on global trace gas distributions, e.g. of BrO, which plays an important role in ozone chemistry or of HONO, which affects the oxidation capacity of the atmosphere. Within the framework of the CARIBIC project (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) a DOAS instrument has been developed. Since May 2005, regular measurement flights are performed once a month onboard a Lufthansa passenger aircraft. During flights to South America and South-East Asia, the DOAS instrument records spectra of UV-visible scattered light from three different viewing directions to derive information on the spatial distribution of trace gases.  HONO mixing ratios in the order of 60 ppt were detected in deep convection clouds, suggesting a lightning induced HONO formation. BrO and NO2 were observed in the upper troposphere in an area charcterized by tropopause folds and strong variations of the tropopause height. These measurements provide insights into troposphere-stratosphere exchange processes. Boundary layer profiles of NO2 and HCHO were derived from descent measurements in Guangzhou/China, yielding mixing ratios of 4.1 ppb for NO2 and 8.2 ppb for HCHO. A discussion of the information content of the CARIBIC DOAS measurements and possible fields of further studies are included.
date: 2007
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/8118/1/Barbara_DIX_Dissertation_Physik_19_12_2007.pdf
identifier: DOI:10.11588/heidok.00008118
identifier: urn:nbn:de:bsz:16-opus-81183
identifier:   Dix, Barbara  (2007) Spectroscopic Measurements of Atmospheric Trace Gases on Long-Distance Flights.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/8118/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng