The shock wave at sea, which does not displace water, moves at 500mph. Water starts moving when the shock wave can no longer start transmitting energy due to the sea bottom shallowing and sloping up gradually. The waves then move at speeds from 20-60mph.
The shock wave at sea, which does not displace water, moves at 500mph
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IOW, the water molecules do not move across the 1000s of miles of ocean. What reaches land is like the last ball in the desk toy of suspended silver balls swinging out when the first ball is made to hit the second ball. Balls 2,3,4,5 and 6 remain immobile. But ball #7 (the end one) swings high, since there is no ball #8 to take the transfer of energy.
Even the waves in these photos, that people are saying do not appear high, have not reached their max height as there is still a lot of water under the sea level.
Our brains can not really compute a picture for which we have no reference, so we assume that these waves are the 6-10ft high ones that we know from our beach experiences.
Believe me those yachties on that beach knew that they were looking at something they had never seen before. - One solid wave from horizon to horizon. Hardly anyone has ever seen that.