Flooding Simulation

This page does several things: A crude simulation of a city-wide flood is presented, with some discussion about how it was made. There are also some thoughts about how simulation can be used as a communication tool, rather than as a predictive tool.

Hopefully this might be interesting to other people who enjoy coding simulations, or might want to use them in science journalism or for educational purposes.

Simulations are usually used to try to predict how some complicated system will behave, or did behave. But they also allow the user to play around with parameters, modify the simulation, watch it, and get detailed information about aspects of the science that they might not be able to with a video, diagram or text.Communicating science to a lay audience is normally complicated by the person not being familiar with terminology and perhaps not having a good enough mental models of what's going on to really understand a textual description. A diagram often helps, as would a video, but to actually present the key parts of how something works, something the reader can play with is possibly more useful. If you imagine how much someone can learn about landing a plane from diagrams and text, compared to being given a flight simulator to spend time in, it seems likely that the simulator would be the most efficient, and perhaps most fun way for the student to learn how the plane actually behaves.

The problem with simulations, though, is that they often were not easy to put into an easily communicated form: perhaps needing hardware, or a large installation on the reader's computer.

In the last ten or so years, though, javascript has become fast enough to run far more detailed simulations than used to be possible, and it can be given to the reader as easily as text can: All they need to do is go to a web page, and it runs automatically.

Another difficulty is that simulations do take longer to write than text. But often the slow part is the model validation step, and for communication purposes or education purposes, this might not be necessary.

With that slight justification, let's show the simulation. Later, I'll talk quickly about how it was made.

What this is

This is a very crude simulation of a potential flood of New Orleans. The pattern of flooding doesn't exactly match the 2005 flooding - and the places where the levees fail in this simulation aren't where they failed in 2005.

Copyright notice: the original data is provided by JAXA. The data presented here is modified.© JAXA