[Brystephor]

How big was the 2011 tsunami? Is 3m bigger or smaller?

[decimalenough]

It's complicated. Tsunami forecasting is a very inexact science and "3m" means "very large".

The average actual height in eastern Japan (Tohoku) was 4-6m, but there were peaks up to 20m in places like Ofunato where the local geography funneled all the water upwards.

https://en.wikipedia.org/wiki/2011_T%C5%8Dhoku_earthquake_an...

[timr]

For perspective, the tsunami that topped the seawall at Fukushima Dai-ichi had a peak height of ~14m.

The seawall was 5.7m.

[hsbauauvhabzb]

Is height the only thing that matters? Presumably 1x 2m wave is less impactful than 10 x 1m waves spread 20 seconds apart?