First observations of tidal oscillations by an MF radar over Kunming (25.6°N, 103.8°E)

Abstract

One year's data of an MF (medium frequency) radar installed at Kunming (25.6°N, 103.8°E) station, China, are used to study the tidal structure over Kunming. The tidal parameters including amplitudes and phases are analyzed, which show a strong diurnal tide and weak semidiurnal tide for both zonal and meridional components. The maxima diurnal and semidiurnal amplitudes are approximately 40 and 20m/s, respectively. The diurnal phases and amplitudes show strong seasonal variability. Maximum amplitudes occur in March, and subsidiary maxima are attained in August and October, while the phase indicates an annual cycle. Semidiurnal amplitudes vary not so evidently. The vertical structures of the tidal parameters are compared with the Global Scale Wave Model (GSWM-09) values. The observed amplitudes of diurnal tide are smaller than the model values, but reversed for the semidiurnal tide. The observed phases of the diurnal tide show similar variations to GSWM-09 values. The agreement between the observed semidiurnal phase and model values is not so good.