A revised linear ozone photochemistry parameterization for use in transport and general circulation models: multi-annual simulations D. Cariolle1,2 and H. Teyssèdre3 1Météo-France, Toulouse, France 2Centre Européen de Recherche et Formation Avancée en Calcul Scientifique, Toulouse, France 3Centre National de Recherches Météorologiques, Météo-France, Toulouse, France
Abstract. This article describes the validation of a linear parameterization of the
ozone photochemistry for use in upper tropospheric and stratospheric studies.
The present work extends a previously developed scheme by improving the 2-D
model used to derive the coefficients of the parameterization. The chemical
reaction rates are updated from a compilation that includes recent laboratory
work. Furthermore, the polar ozone destruction due to heterogeneous reactions
at the surface of the polar stratospheric clouds is taken into account as a
function of the stratospheric temperature and the total chlorine content.
Two versions of the parameterization are tested. The first one only requires
the solution of a continuity equation for the time evolution of the ozone
mixing ratio, the second one uses one additional equation for a cold tracer.
The parameterization has been introduced into the chemical transport model
MOCAGE. The model is integrated with wind and temperature fields from the
ECMWF operational analyses over the period 2000–2004. Overall, the results
from the two versions show a very good agreement between the modelled ozone
distribution and the Total Ozone Mapping Spectrometer (TOMS) satellite data
and the "in-situ" vertical soundings. During the course of the integration
the model does not show any drift and the biases are generally small, of the
order of 10%. The model also reproduces fairly well the polar ozone
variability, notably the formation of "ozone holes" in the Southern
Hemisphere with amplitudes and a seasonal evolution that follow the dynamics
and time evolution of the polar vortex.
The introduction of the cold tracer further improves the model simulation by
allowing additional ozone destruction inside air masses exported from the
high to the mid-latitudes, and by maintaining low ozone content inside the
polar vortex of the Southern Hemisphere over longer periods in spring time.
It is concluded that for the study of climate scenarios or the assimilation
of ozone data, the present parameterization gives a valuable alternative to
the introduction of detailed and computationally costly chemical schemes into
general circulation models.
Citation: Cariolle, D. and Teyssèdre, H.: A revised linear ozone photochemistry parameterization for use in transport and general circulation models: multi-annual simulations, Atmos. Chem. Phys., 7, 2183-2196, doi:10.5194/acp-7-2183-2007, 2007.