Evaluation of transport and ozone loss in the Antarctic polar vortex by using tracer-based coordinates

• Main Author: Ivanova, Ekaterina
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2008
• Subjects: ddc:550; Antarctic; The Antarctic; Antarc*
• Online Access: http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/3590; https://nbn-resolving.org/urn:nbn:de:hebis:30-53927; http://publikationen.ub.uni-frankfurt.de/files/3590/E._Ivanova_PhD_Thesis_Evaluation_of_Transport_and_Ozone_Loss_in_the_Antarctic_Polar_Vortex_by.pdf

The thesis is devoted to the study of the Antarctic polar vortex, mainly by analyzing data collected during APE-GAIA (1999) and ASHOE (1994) campaigns and recorded by the ADEOS satellite (1996-1997), and to improvement of the chromato-graphic processing schemes. A general introduction and overview of the campaigns and instruments relevant to the present work are given in Chapters 1 and 2. A relatively large part of the thesis (Chapters 3-5) is on improvement of the analysis of raw chromatographic data recorded during in-flight measurements of the trace gases. A Gaussian non-straight-base-line method, i.e. the Gaussian processing scheme (Chapter 3), is developed for better evaluation of the chromatographic peak size. Furthermore, a statistical cross-correlation method (Chapter 5) based on statistical behaviour of the whole chromatogram series fNchrg recorded, e.g., during a research flight or laboratory calibration, is developed and applied to measure the low-concentration trace gases. As demonstrated for HAGAR's chromatograms (HAGAR - High Altitude Gas Analyzer), the combination of the Gaussian fitting scheme for individual chromatograms and the statistical cross-correlation method for a series of subsequent chromatograms considerably improves and stabilizes quantitative analysis of in-flight chromatographic data. In this case, the detection accuracy of weak and noisy chromatographic signals can be improved by up to 40 %. A particular attention is paid to the in-flight two-standard calibration method. For this method, a special procedure, that allows to evaluate and effectively remove a weak background chromatographic signal associated with residual molecules in the carrier gas N2, is proposed and coded (Chapter 4). The developed approaches and methods are completely automized and, therefore, can be used for processing of in-flight chromatograms of recent and future field campaigns. The main part of the thesis (Chapters 6-8) deals with a two-dimensional quasi-Lagrangian coordinate system . , based on a ...