TY  - JOUR
AU  - Fröhlich, K.
AU  - Schmidt, T.
AU  - Ern, M.
AU  - Preusse, P.
AU  - de la Torre, A.
AU  - Wickert, J.
AU  - Jacobi, Ch.
TI  - The global distribution of gravity wave energy in the lower stratosphere derived from GPS data and gravity wave modelling: Attempt and challenges
JO  - Journal of atmospheric and solar-terrestrial physics
VL  - 69
SN  - 1364-6826
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - PreJuSER-57885
SP  - 2238 - 2248
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - Five years of global temperatures retrieved from radio occultations measured by Champ (Challenging Minisatellite Payload) and SAC-C (Satelite de Aplicaciones Cientificas-C) are analyzed for gravity waves (GWs). In order to separate GWs from other atmospheric variations, a high-pass filter was applied on the vertical profile. Resulting temperature fluctuations correspond to vertical wavelengths between 400 in (instrumental resolution) and 10 km (limit of the high-pass filter). The temperature fluctuations can be converted into GW potential energy, but for comparison with parameterization schemes GW momentum flux is required. We therefore used representative values for the vertical and horizontal wavelength to infer GW momentum flux from the GPS measurements. The vertical wavelength value is determined by high-pass filtering, the horizontal wavelength is adopted from a latitude-dependent climatology. The obtained momentum flux distributions agree well, both in global distribution and in absolute values, with simulations using the Warner and McIntyre parameterization (WM) scheme. However, discrepancies are found in the annual cycle. Online simulations, implementing the WM scheme in the mechanistic COMMA-LIM (Cologne Model of the Middle Atmosphere-Leipzig Institute for Meteorology) general circulation model (GCM), do not converge, demonstrating that a good representation of GWs in a GCM requires both a realistic launch distribution and an adequate representation of GW breaking and momentum transfer. (c) 2007 Elsevier Ltd. All rights reserved.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000251841800009
DO  - DOI:10.1016/j.jastp.2007.07.005
UR  - https://juser.fz-juelich.de/record/57885
ER  -