On this page you will find:
1. Meridional structures of the Hough functions for the realistic background state of the mean zonal wind and for the background state at rest,
2. Horizontal structures of the Hough harmonics (Kelvin wave, mixed Rossby-gravity wave, Rossby and inertia-gravity waves) for different equivalent depths.
(1) Kelvin Waves
(2) Mixed Rossby-gravity Waves
(3) Eastward-propagating Inertia-gravity Waves
(4) Rossby Waves
(5) Westward-propagating Inertia-gravity Waves
The Effect of the Background Flow on the Meridional Structure of the Hough Functions
Meridional structures of the Hough functions for the zonal wavenumber k=1 and equivalent depth 10 km. The comparison is between the case of the background state at rest and the background flow derived from ERA5 reanalysis data for level 500 hPa and MAM season.
These results reproduce ones from Kasahara, A., 1981: Corrigendum, J. Atmos. Sci. 38, 2284-2285. The original article is Kasahara, A., 1980: Effect of Zonal Flows on the Free Oscillations of a Barotropic Atmosphere, J. Atmos. Sci. 37, 917-929.
These and further Hough harmonics are available for two projections:
Feel free to use them. Please acknowledge the MODES project webpage.
Mixed Rossby-gravity Waves
Eastward-propagating Inertia-gravity Waves
Westward-propagating Inertia-gravity Waves