[KC Burke]

I think what happens Laz is that the wave height varies from event tot event and place to place. As this one reaches shollower water, it increases in height exponentially. At Diego Garcia, the ocean base is so steep just off shore that the wave passes by as a small event.

The record of the century was 1700 ft tall in an Alaska Bay directly accross from a earthquake induced mountain collapse. It scoured the opposite side of the bay to that height removing a forest, so they know its actual height.

The well known one at Hilo came ashore as 30 feet high as I recall the stories.

Each is different based on the volume of water displaced and the sea-bed rise where it comes ashore.

[Travis McGee]

You are correct about the waves having a very different appearance and effect due to offshore and onshore slope etc. I read that the "back" side of Sri Lanka was hit worse than the "front" or eastern side. This is because the waves wrapped around from both north and south, and came in from many directions at once, creating superwave "nodes" and super trough "antinodes" resulting in amazing miles wide whirl pools and eddies and so on. This was worse than "just" getting 6-10 waves straight on in an "orderly" fashion.

[oldcomputerguy]

"1700 ft tall in an Alaska Bay directly across from a earthquake induced mountain collapse."

This was purportedly caused by a landslide event i.e. a slosh. Undersea events cannot cause waves this high.

[SuziQ]

The well known one at Hilo came ashore as 30 feet high as I recall the stories.

That's how we knew about the receding water phenomenon just before a tsunami. There was a show on the History Channel or the Discovery Channel about it.