Disclaimer

HazardSim shows the scale of disasters. It does not predict them, and it must never replace an official warning.

Updated 15 September 2026

A model, not a forecast

Every number HazardSim shows comes from a deliberately simple model running on real terrain and population data. It is designed to answer "roughly how big?" — not "what will happen?". Results can be off by a large factor in either direction. The full list of assumptions is on the How it works page.

What the simulator does not know

• Tsunamis: the shape of the seafloor and coastline, the fault that moved, the tide, the direction the wave comes from, sea walls and breakwaters.
• Sea level rise: land subsidence, storm surges, levees and pumping, how fast change actually happens.
• Earthquakes: fault geometry, depth, local soil amplification, landslides, fires and the condition of individual buildings.
• Volcanoes: wind direction and strength on the day, valley topography that channels flows, lahars, gas.
• Meteors: entry angle, exact speed and composition, fragmentation, whether it falls into the ocean.
• People: casualty estimates assume nobody evacuated and that everyone is at home. Real warnings, time of day and preparedness change outcomes enormously.

Data accuracy

Elevation, city boundaries, population and volcano locations come from third parties (Mapbox, OpenStreetMap, Smithsonian GVP). They can be outdated, incomplete or wrong in places, and errors carry into the results.

Articles

Articles describe past events and scientific estimates using published sources, listed at the end of each article. Figures such as death tolls are often uncertain, and sources disagree; we give ranges where they do. Articles are for general education, not professional advice.

Where to get real information

• Tsunami warnings: tsunami.gov (US National and Pacific Tsunami Warning Centers) and your national warning service.
• Earthquakes: USGS Earthquake Hazards Program, EMSC.
• Volcanoes: Smithsonian Global Volcanism Program and your local volcano observatory.
• Asteroids: NASA JPL Center for Near Earth Object Studies, ESA NEO Coordination Centre.
• Sea level: NASA Sea Level Change, NOAA Sea Level Rise Viewer, IPCC.

Real disasters, real people

Many places on the map have lived through the events the simulator imitates. HazardSim exists to make those events understandable, not to trivialise them.