Some experimental constraints for spectral parameters used in the Warner and McIntyre gravity wave parameterization scheme M. Ern1, P. Preusse1, and C. D. Warner2 1Institute for Stratospheric Research (ICG-I), Forschungszentrum Juelich, Juelich, Germany 2Centre for Atmospheric Science, University of Cambridge, Cambridge, UK
Abstract. In order to incorporate the effect of gravity waves (GWs) on the atmospheric
most global circulation models (GCMs) employ gravity wave parameterization
To date, GW parameterization schemes in GCMs are used without experimental
validation of the set of global parameters assumed for the GW launch spectrum.
This paper focuses on the Warner and McIntyre GW parameterization scheme.
Ranges of parameters
compatible with absolute values of gravity wave momentum flux (GW-MF)
derived from CRISTA-1 and CRISTA-2 satellite measurements
are deduced for several of the parameters and the limitations of both
model and measurements are discussed.
The findings presented in this paper show that the initial guess
of spectral parameters provided by by Warner and McIntyre (2001) are some kind of compromise with respect to agreement of
absolute values and agreement of the horizontal structures found in both
measurements and model results.
Better agreement can be achieved by using a vertical wavenumber
launch spectrum with a wider saturated spectral range and reduced
spectral power in the unsaturated part.
However, even with this optimized set of global launch parameters not all
features of the measurements are matched. This indicates that for further
improvement spatial and seasonal variations of the launch parameters should
be included in GW parameterization schemes.
Citation: Ern, M., Preusse, P., and Warner, C. D.: Some experimental constraints for spectral parameters used in the Warner and McIntyre gravity wave parameterization scheme, Atmos. Chem. Phys., 6, 4361-4381, doi:10.5194/acp-6-4361-2006, 2006.