The global distribution of gravity wave energy in the lower stratosphere derived from GPS data and gravity wave modelling: attempt and challenges

K. FRÖHLICH, T. SCHMIDT, M. ERN, P. PREUSSE, A. DE LA TORRE, J. WICKERT, CH. JACOBI

JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS

Elsevier

Lugar: Edinburgo; Año: 2007 vol. 69 p. 2238 - 2248

1364-6826

Two gravity wave (GW) parameterization schemes have alternatively been implemented into a middle atmosphere circulation model in order to study GW processes. However, still there remain several unknown parameters to be tuned in the GW parameterizations. One important factor is the initial value of gravity wave momentum flux and its latitudinal and longitudinal distribution. There already exist global estimates of gravity wave potential energy in the troposphere and lower stratosphere. These data are retrieved from radio occultations made by CHAMP (Challenging Minisatellite Payload) and SAC-C (Satelite de Aplicaciones Cientificas-C) and comprise more than 5 years. This GPS data set is used to deduce the global characteristics of gravity wave activity. At this stage it is not possible to transfer the information of GPS data straightforward to the model since several limitations have to be taken into account as, for instance, the restricted satellite visibility and the missing information about horizontal wavelengths. Therefore, the global allocated GW energy will be analyzed and compared to the GW flux in the model and the input parameters of the parameterization scheme will be adapted towards a more realistic distribution.