scostep 2010 (stp12) - Leibniz-Institut für Atmosphärenphysik an der ...

STP12 Abstracts
Berlin, 12 - 16 July 2010
SCOSTEP Symposium 2010
Diagnosis of zonal asymmetries in stratospheric ozone and water vapor and their
influence on circulation from tropo- to mesosphere
Gabriel Axel 1 , Peters Dieter 1 , Kirchner Ingo 2 , Graf Hans-F. 3
1 Leibniz-Institut für Atmosphärenphysik der Universität Rostock e.V., 2 Meteorologisches Institut,
Freie Universität Berlin, 3 Centre Atmospheric Science, University Cambridge, UK
We present a diagnosis of zonally asymmetric components in stratospheric ozone and water vapor and
their long-term changes based on both assimilated data (ERA-40, ERA-Interim) and satellite data
(SAGE, GOME, ODIN). Zonal asymmetries in strato- and mesospheric tracers are related to ultra-long
quasi-stationary planetary waves, which increase during autumn, maintain during winter and decay
during spring. For northern and southern hemisphere winter, we found pronounced wave one
structures in both ozone and water vapor with maximum amplitudes up to about 20% of zonal mean
values. Long-term changes include a nearly linear trend in amplitude and some pronounced variations
which may partly be due to the 11-year cycle in solar radiation activity. Based on model simulations
we investigate the influence of the related radiation perturbations and possible feedback processes
between the planetary wave patterns in temperature, dynamics and chemistry. Sensitivity studies with
the GCM MAECHAM5 and prescribed zonally asymmetric ozone show a significant increase in
amplitude and a shift in phase of wave one structure in temperature and geopotential, accompanied by
a longitudinal shift of up- and eastward directed quasi-stationary wave trains. Long-term equilibrium
simulations with the CCM HAMMONIA show that the 11-year solar radiation cycle can lead to
significant changes in the ultra-long planetary wave patterns in dynamics and chemistry. The results
suggest that zonal asymmetries in ozone, water vapor and other absorbers may be an important factor
in understanding observed long-term changes in dynamics and chemistry.