The stationarity of the internal tides generated in a global eddy-resolving ocean circulation model is explored using 5 years of model output. The simulated internal tide is first compared with estimates obtained from altimetric sea-surface heights. Both the model and observations show strong generation of internal tides at a limited number of “hot spot” regions with propagation of beams of energy for thousands of kilometers away from the sources. The model tidal amplitudes compare well with observations near these energetic tidal regions. Averaged over these regions, the model and observation amplitude estimates agree to approximately 15% for the 4 largest semi-diurnal constituents and 23% for the 4 largest diurnal constituents. Overall the RMS variability in the M2 tidal amplitude is approximately .2 cm or larger over most of the Pacific and Indian Ocean. The RMS variability of the M2 tidal amplitude can approach the mean amplitude in weaker tidal areas such as the tropical Pacific and eastern Indian Ocean, but it is small in relation to the mean amplitude over the hot spot regions. This suggests that the simulated internal tide is largely stationary over the hot spot regions.
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