Advanced Tsunami Travel Time Calculator
Estimate tsunami speed from distance, depth, and route inputs. Review scenarios using practical science tools. Get clear arrival insights for coastal readiness planning today.
This calculator estimates tsunami travel time using long-wave physics, average ocean depth, and route adjustments. It is useful for first-pass planning, scenario testing, and educational modeling.
Tsunami Travel Time Calculator
Plotly Graph
This chart shows how estimated travel time changes when average depth changes while other selected assumptions stay fixed.
Formula Used
c = √(g × h)deff = d × pcadj = c × (1 - s/100)t = deff / cadjt × (1 ± u/100)Here, g is gravity, h is average ocean depth, d is source-to-target distance, p is the path multiplier, s is the slowdown percentage, and u is uncertainty.
This is a simplified physics model for first-pass travel-time estimation. It does not replace detailed hazard mapping, local bathymetry analysis, or inundation studies.
How to Use This Calculator
- Enter the travel distance between tsunami source and target coast.
- Select the correct distance unit.
- Enter a representative average ocean depth along the wave path.
- Keep gravity at 9.81 m/s² unless you need a custom value.
- Use the path multiplier to reflect curved or indirect routes.
- Use coastal slowdown to approximate shoaling-related speed reduction.
- Add an uncertainty percentage for quick scenario bands.
- Enter warning delay to estimate usable lead time.
- Press calculate to show results above the form.
- Download the results as CSV or PDF if needed.
Example Data Table
| Scenario | Distance | Depth | Path Multiplier | Slowdown | Estimated Speed | Estimated Travel Time |
|---|---|---|---|---|---|---|
| Open ocean route | 900 km | 4000 m | 1.08 | 6% | 186.20 m/s | 1 hr 27 min |
| Longer basin route | 1500 km | 4500 m | 1.12 | 8% | 193.44 m/s | 2 hr 25 min |
| Shorter regional route | 350 km | 3200 m | 1.04 | 5% | 168.24 m/s | 36 min |
1. What does this calculator estimate?
It estimates how long a tsunami wave may take to travel from a source region to a target coastline using average depth and long-wave speed assumptions.
2. Why is ocean depth important?
In the long-wave model, wave speed depends on the square root of gravity times water depth. Deeper water usually means faster travel.
3. What is the path multiplier for?
It lets you increase straight-line distance when the likely travel route bends around basins, trenches, islands, or continental margins.
4. What does coastal slowdown represent?
It approximates reduced propagation speed as waves enter shallower regions near land. It is a practical adjustment, not a full shoaling simulation.
5. Is this suitable for official warning operations?
No. It is best for education, planning exercises, and rough scenario checks. Official warning systems use real-time seismic, buoy, and bathymetric data.
6. Why include an uncertainty band?
Tsunami paths and real ocean conditions vary. The uncertainty band gives a quick early-and-late arrival window for planning discussions.
7. What is warning window time?
It subtracts your warning issuance delay from the estimated arrival time, showing how much practical lead time may remain.
8. Can I use miles or feet?
Yes. The calculator converts common distance and depth units into metric values internally before computing speed and travel time.