Chemical Ozone Loss in the Arctic Polar Stratosphere : an analysis of twelve years of satellite observations

• Main Author: Tilmes, Simone
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag 2004
• Subjects: info:eu-repo/classification/ddc/333.7; Arctic; Ilas
• Online Access: https://juser.fz-juelich.de/record/36697; https://juser.fz-juelich.de/search?p=id:%22PreJuSER-36697%22

In this thesis, the chemical ozone loss in the Arctic stratosphere was investigated for twelve years between 1991-92 and 2002-03. The accumulated local ozone loss and the column ozone loss were consistently derived using the ozone-tracer correlation (TRAC) technique. This technique considers the relation between ozone and a long-lived tracer during the lifetime of the polar vortex. Results are presented on the basis of observations obtained from two solar occultation satellite instruments: ILAS (Improved Limb Atmospheric Spectrometer) aboard the ADEOS satellite (Advanced Earth Observing Satellite) and HALDE (Halogen Occultation Experiment) aboard the UARS satellite (Upper Atmosphere Research Satellite). The HALDE observations used in the present work have been available since October 1991. The instrument made measurements during a period of a few days every two or three months in high northern latitudes during the entire period between 1991 and 2003. The ILAS instrument performed mear surements continuously from November 1996 to June 1997 in the high latitude region of both hemispheres. In the present work, the TRAC method was confirmed against criticism raised in the past. The improved and extended method permits both a reduction and a better quantification of uncertainties. New procedures implemented in the method allow the ozone loss for the winter to be calculated, in case where no results could have been derived in the past. Therefore, a consistent analysis is possible for the twelve winters. An intensive analysis of chemical ozone loss is performed considering as an example the winter 1996-97, for which measurements from both HALDE and ILAS are available. The ILAS observations allow a detailed analysis of the temporal evolution of the ozone-tracer correlation inside the polar vortex for the first time and in particular of the development of the early vortex. Especially the influence of mixing between vortex air and air from outside the vortex is discussed. The evolution of significant PSC-related chemical ...