Features
Real Physics Simulation
Solves the shallow water equations — the same mathematical framework used by real tsunami warning centers — with an HLL Riemann solver for accurate wave propagation.
GPU Accelerated
The entire simulation runs on your GPU via Apple Metal compute shaders, enabling real-time wave propagation across thousands of grid cells simultaneously.
Global Coverage
Real bathymetry data ensures waves accelerate in deep ocean (~720 km/h) and slow down in shallow coastal waters — just like real tsunamis. Waves cross the International Date Line seamlessly.
11,000+ Cities
See which cities would be impacted with Modified Mercalli Intensity estimates based on hypocentral distance, magnitude, and earthquake depth.
Well-Balanced Numerics
Hydrostatic reconstruction (Audusse et al. 2004) ensures a calm ocean stays calm — no fake ripples from bathymetry steps or shoreline boundaries.
Educational
Understand why shallow earthquakes are more dangerous, how ocean depth affects wave speed, and why some coastlines are more vulnerable to tsunamis.
How It Works
Tap the Map
Select any location in the ocean to simulate an earthquake epicenter.
Set Magnitude & Depth
Choose earthquake magnitude (1–10) and focal depth (1–700 km). Only shallow quakes under 70 km generate tsunamis — just like in reality.
Watch Simulation
Observe waves propagate in real-time, reflect off coastlines, and flood coastal areas.
The Science Behind the Simulation
Shallow Water Equations
Solves mass conservation and momentum equations in 2D conservative form — computing wave height and velocity at every grid point, every timestep.
HLL Riemann Solver
A proven numerical method for computing wave propagation across cell interfaces. Accurately captures shock waves, rarefaction fans, and wave interactions.
Hydrostatic Reconstruction
State-of-the-art technique (Audusse et al. 2004) that prevents spurious numerical waves at coastlines. Ensures physically accurate behavior at every shoreline.
Real Bathymetry
Uses actual ocean floor elevation data from Natural Earth. Wave speed depends on water depth — waves travel ~720 km/h in deep ocean and slow dramatically near coasts.
Realistic Wave Physics
CFL-stable adaptive timestep, Manning friction for seafloor interaction, sponge layer boundaries to absorb outgoing waves, and periodic longitude wrapping for global tsunamis.
Seismological Accuracy
Earthquake depth affects surface intensity via hypocentral distance. Only shallow quakes (<70 km) generate tsunamis. Damage estimates use the Modified Mercalli Intensity scale.
Requirements
- iOS 18.0 or later
- iPadOS 18.0 or later
- macOS 15.0 or later
- Metal GPU support
Support
Contact
Questions or feedback? Email us at walter.tengler@gmail.com
FAQ
Terramoto uses GPU-accelerated physics to simulate wave propagation. The simulation is simplified for educational purposes and should not be used for emergency planning.