¥When
wave packets propagate upward, according to the wave capture theory,
¥Horizontal
wave number increases to infinity and align with the local dilatation axis.
¥Intrinsic
group velocity vanishes and wave packets are advected by the mean wind.
¥Intrinsic
frequency decrease near inertial frequency.
¥Consider
the temporal and spatial variations of the background wind from the dipole simulation.
¥With
four dimensional ray tracing model (GROGRAT), we initialize rays at different locations by specifying horizontal
wave vectors, phase speed and frequency.
¥Initial
horizontal wavelength of 100 ~ 500km and phase speed of -8 ~ 8 m/s. Pickup rays that can be actually observed.
E.g., discard rays that propagate above 5km since no gravity waves observed
above that level after 270 hour for the surface dipole case.