Surf Similarity Iribarren Number
Calculate deep-water surf similarity and caller regime bands, with upper band including equality; not a beach safety classification or universal breaker threshold.
Description
Surf similarity compares beach slope with deep-water wave steepness.
Surf similarity compares beach slope with deep-water wave steepness. Regime boundaries depend on the selected convention.
Calculate deep-water surf similarity and caller regime bands, with upper band including equality; not a beach safety classification or universal breaker threshold.
When to use Surf Similarity Iribarren Number
Use this tool to calculate deep-water surf similarity and caller regime bands, with upper band including equality; not a beach safety classification or universal breaker threshold.
Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.
How to use Surf Similarity Iribarren Number and understand its results
- Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.
- Enter beachSlopeTangent, deepWaterWaveHeightM, wavePeriodSeconds, gravityMPerSecondSquared, callerTransitionBounds using the field table and calculation rules, then run the tool.
- Read iribarrenNumber, callerRegimeCode. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| beachSlopeTangent | Beach slope tangent | number | Required |
| deepWaterWaveHeightM | Deep water wave height m | number | Required |
| wavePeriodSeconds | Wave period seconds | number | Required |
| gravityMPerSecondSquared | Gravity m per second squared | number | Required |
| callerTransitionBounds | Caller transition bounds | list of number | Required |
Use positive height, period and gravity, nonnegative slope and two increasing positive thresholds. Compute wavelength gT²/(2π); codes 0,1,2 use lower-inclusive and upper-inclusive entry into the next band.1
Iribarren = slope tangent/sqrt(wave height/deep-water wavelength) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| iribarrenNumber | Iribarren number | number |
| callerRegimeCode | Caller regime code | number |
{
"input": {
"beachSlopeTangent": 0.1,
"deepWaterWaveHeightM": 1,
"wavePeriodSeconds": 6.283185307179586,
"gravityMPerSecondSquared": 1,
"callerTransitionBounds": [
0.1,
1
]
},
"output": {
"iribarrenNumber": 0.25066282746310004,
"callerRegimeCode": 1
}
}Limitations and assumptions
Caller regimes do not certify beach safety or universal breaker type.
Numbers and computed results must be finite; overflow produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Runup Stockdon Total: Evaluate the empirical Stockdon 2006 general-beach R2 formulation and add supplied still water; not a dune overtopping probability, tsunami model or guaranteed maximum. For a complementary task, use Wave Dispersion Relation Root Solver: Solve finite-depth linear dispersion omega²=g k tanh(kh) by bounded dimensionless bisection, returning phase/group speeds without deep/shallow aliases.
References
-
Surf Similarity Iribarren Number — tool.io
Similar or alternative tools
- Runup Stockdon Total
Evaluate the empirical Stockdon 2006 general-beach R2 formulation and add supplied still water; not a dune overtopping probability, tsunami model or guaranteed maximum.
- Wave Dispersion Relation Root Solver
Solve finite-depth linear dispersion omega²=g k tanh(kh) by bounded dimensionless bisection, returning phase/group speeds without deep/shallow aliases.