Heavily damaging tsunami hits New York

[flay]

http://tsunami-maps....=0&hgt=6&rng=50

 

Actually this is just a link for my new web site "tsunami-maps.com". It uses the google maps elevation service, the flood fill algorithm and lots of JavaScript to simulate tsunamis on your local beach.

 

Its not 100% scientifically accurate but maybe entertain some people for 5 mins. Actually if someone has some ideas/links on how to improve the site's accuracy let me know (tsunami.maps@gmail.com).

[CaptainPanic]

Meh,

 

The simulator does not seem to take sea walls or other defense against high water into account. It just maps a blue color over the average height of the land, which is completely inaccurate especially for low countries like the Netherlands.

 

It predicts that a 2 meter high wave would swamp the Netherlands up to 50 km inland... but we regularly survive storms (albeit not tsunamis) which raise the water by way more than 2 meters... and not a single drop of water floods into the country. We have proper protection against high sea levels. In fact, the primary sea defense should be so sturdy that even the heaviest storms of the millenium should not be able to flood the country.

 

The primary sea defense is about 12 meters high. Secondary dikes that are built inland can still be 2-3 meters high. The entire country is divided into areas which are surrounded by dikes and canals. Land around rivers is also protected by dikes and the entire country is full of secondary, ternary, etc. dikes. We can even close off the port of Rotterdam completely. The result is that your simulation is very inaccurate - or, I could also say that the result is that it's really difficult to model flooding in the Netherlands...

 

Sorry to be so harsh.

[flay]

Meh,

 

The simulator does not seem to take sea walls or other defense against high water into account. It just maps a blue color over the average height of the land, which is completely inaccurate especially for low countries like the Netherlands.

 

It predicts that a 2 meter high wave would swamp the Netherlands up to 50 km inland... but we regularly survive storms (albeit not tsunamis) which raise the water by way more than 2 meters... and not a single drop of water floods into the country. We have proper protection against high sea levels. In fact, the primary sea defense should be so sturdy that even the heaviest storms of the millenium should not be able to flood the country.

 

The primary sea defense is about 12 meters high. Secondary dikes that are built inland can still be 2-3 meters high. The entire country is divided into areas which are surrounded by dikes and canals. Land around rivers is also protected by dikes and the entire country is full of secondary, ternary, etc. dikes. We can even close off the port of Rotterdam completely. The result is that your simulation is very inaccurate - or, I could also say that the result is that it's really difficult to model flooding in the Netherlands...

 

Sorry to be so harsh.

 

Hi - a little bit of background...

 

It is a work in progress and the aim of this application is not to be a 100% reliable scientific simulation, but more a general guide to see which areas are most likely to be affected by a tsunami. Some places don't have the budget to run a big study on the local effects of tsunamis (much less the budget to build 15m walls!) and one of my goals here is to give a cheap way to start. Plus some people find is entertaining for 10 mins Accurate tsunami threat modelling requires a super computer, very detailed topo information and knowledge of the terrain, and (as you say) knowledge of walls etc built to keep big waves out. which is not really going to be practical on a site like this.

 

However, if someone really wanted to really be harsh, my main limitation here is lack of a energy model. That is the current model just uses elevation vs wave height, range and the flood fill algorithm (ref: http://en.wikipedia.org/wiki/Flood_fill) to determine inundation. This is simple but gets the current limited results. In reality a low wave with high energy could rise several meters above its original height whereas a low energy but high wave may only go a short distance inland after losing its energy to the terrain or just running out of volume.

 

Maybe someone in this group can suggest a simple but accurate way to do this? The algorithm has access to the topo information over a grid, we can prompt the users for any number of parameters (speed, volume etc.) and I'm looking for a simple computation model to determine inundation from this.