We have presented a numerical model of non-migrating tides assuming a differential heating local-ized only on land caused by upward heat flux in the planetary boundary layer. The amplitude of the diurnal temperature oscillation corresponding to the heat source is assumed to be 3K at the ground at the equator, and to decay exponentially with a scale height of 1km. Horizontal and vertical structures of non-migrating tides are solved by using classical tidal theory, in which a land-sea distribution is expanded into a complex Fourier series at each latitude with longitudinal wavenumbers ranging from -20 to 20, and further expressed by about 40 Hough modes for each zonal wavenumber. We have found that the horizontal distribution of the heat source has more significant effects on the behavior of non-migrating tides than the vertical distribution.
The model pressure variations of non-migrating tides correlate well with the land-sea distribution at the ground, and agree excellently with observations. They are confined to a region equatorward of 30° latitude, while they spread longitudinally with increasing altitude, which is attributed to the imbalance between the westward and eastward propagating components. Horizontal wind velocities of non-migrating tides are about 2 to 3m/s near 20km altitude, and have vertical wavelengths as short as 2 to 5km, which is fairly consistent with ground-based radar observations.