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Comment by alphonsegaston | Hacker News Reader

There are three to six hundred year old stones that dot the northern coastline of Japan, telling people not to build below a certain point because of tsunamis. This wasn't a once in a millennium event.

https://mobile.nytimes.com/2011/04/21/world/asia/21stones.ht...

Unfortunately, humanity no longer seems wise enough to extend this same concern for future generations.

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You misunderstand what a 1 in x event means it is a probability not a clock.

We had 2 1/250 year floods in my village within 5 years - exacerbated by the land owners not maintain the waterways on their property

This is not one event 600 years ago, this is several events over 600+ years where people marked safe areas. 26,000 died in this one but even with a smaller population in 1896 one killed 22,000 people. These are 1:100 year events not 1:1,000 year events and people are really bad about things that happen less frequently than 1:50 years or so.

I didn't misunderstand anything about probability. Japan is among the most seismically active regions in the world and tsunamis and large earthquakes are(in historical terms) a regular occurrence.

https://en.m.wikipedia.org/wiki/List_of_historical_tsunamis

https://en.m.wikipedia.org/wiki/List_of_historical_earthquak...

They don't hem to this probability no matter how you try and frame it.

The term is misleading and leads to poor decision-making

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