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| Titel |
Simulation of non-hydrostatic gravity wave propagation in the upper atmosphere |
| VerfasserIn |
Y. Deng, A. J. Ridley |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
0992-7689
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| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 32, no. 4 ; Nr. 32, no. 4 (2014-04-24), S.443-447 |
| Datensatznummer |
250121052
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| Publikation (Nr.) |
 copernicus.org/angeo-32-443-2014.pdf |
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| Zusammenfassung |
| The high-frequency and small horizontal scale gravity waves may be reflected
and ducted in non-hydrostatic simulations, but usually propagate vertically
in hydrostatic models. To examine gravity wave propagation, a preliminary
study has been conducted with a global ionosphere–thermosphere model (GITM),
which is a non-hydrostatic general circulation model for the upper
atmosphere. GITM has been run regionally with a horizontal resolution of
0.2° long × 0.2° lat to resolve the gravity wave
with wavelength of 250 km. A cosine wave oscillation with amplitude of
30 m s−1 has been applied to the zonal wind at the low boundary, and
both high-frequency and low-frequency waves have been tested. In the
high-frequency case, the gravity wave stays below 200 km, which indicates
that the wave is reflected or ducted in propagation. The results are
consistent with the theoretical analysis from the dispersion relationship
when the wavelength is larger than the cutoff wavelength for the
non-hydrostatic situation. However, the low-frequency wave propagates to the
high altitudes during the whole simulation period, and the amplitude
increases with height. This study shows that the non-hydrostatic model
successfully reproduces the high-frequency gravity wave dissipation. |
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