Abstract
Strange huge tidal waves occur sometimes around the coastal area of the Japan Proper, especially on the band region of 30°00.0'-35°42.5'N. This paticular phenomena appear with the period of 11.62-11.75 years. When this sort of long wave beggins to accumulate its enormous amount of energy to run off and sweep away on the continental shelf, special oscillations both in the ocean bed and on the ionosphere are created. These wave periods are analysed as 4.68730-5.71820 hours in the air and 4.89768-6.11242 hours in the water. Their original travelling velocities are 1557.59m/sec and 1525.62m/sec respectively, which correspond to the sonic speed of 1513.00m/sec in the sea water.
