Determination of the distribution of halocarbons in the tropical upper troposphere and stratosphere [Elektronische Ressource] / vorgelegt von Johannes Christian Laube

Jlaube

Informations

• Publié par: goethe_universitat_frankfurt_am_main
• Publié le: 01 janvier 2008
• Nombre de lectures: 20
• Langue: English
• Poids de l'ouvrage: 3 Mo

Extrait

Determination of the distribution of halocarbons in the tropical
upper troposphere and stratosphere




Dissertation
zur Erlangung des Doktorgrades
der Naturwissenschaften






vorgelegt beim Fachbereich 14
der Johann Wolfgang Goethe – Universität
in Frankfurt am Main






vorgelegt von
Johannes Christian Laube
aus Jena






Frankfurt (2008)







I










vom Fachbereich 14 der



Johann Wolfgang Goethe – Universität als Dissertation angenommen.























Dekan : Prof. Dr. H. Schwalbe



Gutachter : Prof. Bernd O. Kolbesen, PD Dr. Andreas Engel



Datum der Disputation : 20.10.2008
II Table of contents

0 Introduction....................................................................................................................... 1

1 Scientific background..................................................................................................... 3
1.1 Halocarbons in the atmosphere .................................................................................... 3
1.1.1 Atmospheric composition and quantities .................................................................. 3
1.1.2 Atmospheric regions - troposphere and stratosphere ................................................ 4
1.1.3 Substance classification............................................................................................. 7
1.1.4 Ozone depletion and fractional release factors ......................................................... 8
1.1.5 Tracer-tracer-correlations and the concept of age of air ......................................... 10
1.2 Analytical methods....................................................................................................... 12
1.2.1 Air sampling techniques.......................................................................................... 12
1.2.2 Gas Chromatography with Electron Capture Detection.......................................... 13
1.2.3 Mass Spectrometry.................................................................................................. 14

2 Analytical system and data analysis........................................................................ 16
2.1 Configuration of the GC-ECD-MS............................................................................. 16
2.1.1 Pre-concentration system ........................................................................................ 16
2.1.2 Chromatography and detector details...................................................................... 18
2.2 Identification of substances ......................................................................................... 19
2.2.1 Identification via synthetic EI-Scan ........................................................................ 19
2.2.2 Identification and confirmation via EI-SIM and EI-Scan ....................................... 22
2.2.3 Confirmation via NICI ............................................................................................ 22
2.3 Data analysis ................................................................................................................. 26
2.4 Peak integration............................................................................................................ 28
2.5 Linearity of the quantification method ...................................................................... 35
2.6 Conclusions ................................................................................................................... 38

3 Quality assurance........................................................................................................... 39
3.1 Stability of substances in calibration and sample containers................................... 40
3.1.1 Calibration container evaluation ............................................................................. 41
3.1.2 Sample container evaluation ................................................................................... 44
3.1.3 Dilution series evaluation........................................................................................ 47
3.2 Internal detector comparison...................................................................................... 49
3.2.1 ECD evaluation regarding coeluents....................................................................... 50
3.2.2 Comparison of different ECD nonlinearity corrections .......................................... 51
3.2.3 Systematic comparison of stratospheric detector results......................................... 54
3.3 Calibrations and cross-comparisons........................................................................... 55
3.3.1 Calibration of substances ........................................................................................ 55
3.3.2 Cross-comparison with the University of East Anglia............................................ 56
3.3.3 Cross-comparison with the Max-Planck-Institute for Chemistry ........................... 56
3.4 Conclusions ................................................................................................................... 58





III 4 Tracer-tracer-correlations and fractional release factors of long-lived
halogenated substances in the tropical stratosphere ............................................ 60
4.1 Introduction .................................................................................................................. 60
4.2 Tracer-tracer correlations........................................................................................... 62
4.3 Calculation of fractional release factors..................................................................... 67
4.4 Results and comparisons of fractional release factors.............................................. 71
4.5 Conclusions ................................................................................................................... 77

5 Contribution of very short-lived organic substances to stratospheric
chlorine and bromine in the tropics – a case study............................................... 79
5.1 Introduction and air sample origin............................................................................. 79
5.2 Analytical procedure.................................................................................................... 80
5.3 Corrections, comparisons and air mass origin .......................................................... 82
5.3.1 Concentration drift correction ................................................................................. 82
5.3.2 Intercomparison with ground-based observations................................................... 83
5.3.3 Air mass origin ........................................................................................................ 84
5.4 Organic chlorine and bromine .................................................................................... 86
5.5 Inorganic chlorine and bromine ................................................................................. 92
5.6 Conclusions ................................................................................................................... 97

6 First atmospheric observations of three chlorofluorocarbons ...................... 98
6.1 Introduction .................................................................................................................. 98
6.2 Analytical Procedure.................................................................................................... 99
6.3 Identification of the substances in a plume................................................................ 99
6.4 Mixing ratio estimates, calibration and air mass origin ......................................... 105
6.5 Subsequent observations............................................................................................ 107
6.6 Conclusions ................................................................................................................. 109

7 Summary and outlook................................................................................................ 110

Publications ....................................................................................................................... 114

References .......................................................................................................................... 115

List of Figures................................................................................................................... 130

List of Tables..................................................................................................................... 135

Acknowledgements ......................................................................................................... 137

Zusammenfassung und Ausblick................