|
Titel |
Reconstruction of the gravity wave field from convective plumes via ray tracing |
VerfasserIn |
S. L. Vadas, D. C. Fritts |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
0992-7689
|
Digitales Dokument |
URL |
Erschienen |
In: Annales Geophysicae ; 27, no. 1 ; Nr. 27, no. 1 (2009-01-09), S.147-177 |
Datensatznummer |
250016363
|
Publikation (Nr.) |
copernicus.org/angeo-27-147-2009.pdf |
|
|
|
Zusammenfassung |
We implement gravity wave (GW) phases into our
convective plume and anelastic ray trace models.
This allows us to successfully
reconstruct the GW velocity, temperature, and density
perturbation amplitudes and phases in the Mesosphere-Lower-Thermosphere (MLT)
via ray tracing (in real space) those GWs that are excited
from a deep convective plume.
We find that the ray trace solutions agree very well with the exact, isothermal, zero-wind,
Fourier-Laplace solutions in the Boussinesq limit.
This comparison also allows us to determine the normalization factor which converts the
GW spectral amplitudes to real-space amplitudes in the ray trace model.
This normalization factor can then be used for ray tracing GWs through
varying temperature and wind profiles.
We show that by adding GW reflection off the Earth's surface,
the resulting GW spectrum has more power at larger vertical
and horizontal wavelengths.
We determine the form of the momentum flux and velocity spectra which
allows for easy calculation of GW amplitudes in the MLT and thermosphere.
Finally, we find that the reconstructed (ray traced) solution for
a deep, convective plume with a duration much shorter than
the buoyancy period does not equal the Fourier-Laplace Boussinesq solution;
this is likely due to errors in the Boussinesq dispersion relation
for very high frequency GWs. |
|
|
Teil von |
|
|
|
|
|
|