Tsunami

An undersea earthquake heaves the sea floor and the water above it. The shallow-water equations then carry that disturbance across the ocean at c = √(g·h) and onto a coast with a bay and an island.

Map click tool

Click the deep ocean to place the earthquake epicentre.

Magnitude 9.0 Fault orientation 0° Time speed 3 min/s Colour range ±2.0 m

Show Wave height Bathymetry contours Inundation Tide gauges Wavefront lines Travel-time rings Nonlinear terms Place labels

Tide gauges

Pick the “Tide gauge” tool, then click water (up to 4). Click a gauge again to remove it.

What is happening

Solver: staggered-grid nonlinear shallow-water equations (200×150 cells of 4 km, Δt = 6 s) with Manning friction and a wet/dry front for run-up. Edges of the ocean absorb waves. Resolution is coarse, so coastal heights are indicative, not forecasts.