The impact of transport across the polar vortex edge on Match ozone loss estimates J.-U. Grooß1, R. Müller1, P. Konopka1, H.-M. Steinhorst1, A. Engel2, T. Möbius2, and C. M. Volk2 1Forschungszentrum Jülich, Institut für Chemie und Dynamik der Geosphäre, ICG-1: Stratosphäre, Germany 2Johann Wolfgang Goethe-Universität, Frankfurt, Institut für Atmosphäre und Umwelt, Germany
Abstract. The Match method for the quantification of polar chemical ozone loss
is investigated mainly with respect to the impact of the transport
of air masses across the vortex edge.
For the winter 2002/03, we show that significant transport across
the vortex edge occurred and was simulated by the Chemical
Lagrangian Model of the Stratosphere. In-situ observations of inert
tracers and ozone from HAGAR on the Geophysica aircraft and
balloon-borne sondes, and remote observations from MIPAS on the
ENVISAT satellite were reproduced well by CLaMS. The model even
reproduced a small vortex remnant that remained a distinct feature
until June 2003 and was also observed in-situ by a balloon-borne
whole air sampler.
We use this CLaMS simulation to quantify the impact of transport
across the vortex edge on ozone loss estimates from the Match method.
We show that a time integration of the determined vortex average
ozone loss rates, as performed in Match, results in a larger ozone loss
than the polar vortex average ozone loss in CLaMS.
The determination of the Match ozone loss rates is also influenced
by the transport of air across the vortex edge. We use the model
to investigate how the sampling of the ozone sondes on which Match
is based represents the vortex average ozone loss rate.
Both the time integration of ozone loss and the determination of
ozone loss rates for Match are evaluated using the winter 2002/2003
CLaMS simulation. These impacts can explain the majority of the
differences between CLaMS and Match column ozone loss.
While the investigated effects somewhat reduce the apparent
discrepancy in January ozone loss rates reported earlier, a distinct
discrepancy between simulations and Match remains. However, its
contribution to the accumulated ozone loss over the winter is not
Citation: Grooß, J.-U., Müller, R., Konopka, P., Steinhorst, H.-M., Engel, A., Möbius, T., and Volk, C. M.: The impact of transport across the polar vortex edge on Match ozone loss estimates, Atmos. Chem. Phys., 8, 565-578, doi:10.5194/acp-8-565-2008, 2008.