Bathymetric Penetration
Calculate bathymetric optical penetration depth from attenuation and detection threshold.
Description
An exponential attenuation model converts a minimum detectable transmission to an optical path length.
An exponential attenuation model converts a minimum detectable transmission to an optical path length. A reflection measurement consumes that path on outgoing and returning legs.1
Calculate bathymetric optical penetration depth from attenuation and detection threshold.
When to use Bathymetric Penetration
Use this tool to calculate bathymetric optical penetration depth from attenuation and detection threshold.
Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
How to use Bathymetric Penetration and understand its results
- Prepare the optical measurements, geometry, fitted coefficients or caller-selected thresholds requested. Confirm wavelength, radius/diameter, pulse-width, angle and unit conventions before running the calculation.
- Enter attenuationPerMeter, minimumTransmissionFraction using the field table and calculation rules, then run the tool.
- Read maximumOneWayDepthMeters, maximumRoundTripDepthMeters. 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 |
|---|---|---|---|
| attenuationPerMeter | Water attenuation coefficient (1/m) | number; minimum: 0 | Required |
| minimumTransmissionFraction | Minimum detectable transmission | number; minimum: 0; maximum: 1 | Required |
Enter positive attenuation and transmission fraction in (0,1]. Return one-way-path depth and round-trip-measurement depth in meters. Unity transmission yields zero.
path=−ln(minimumTransmission)/attenuation; reflectionDepth=path/2 Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| maximumOneWayDepthMeters | Maximum one-way depth (m) | number; minimum: 0 |
| maximumRoundTripDepthMeters | Maximum round-trip depth (m) | number; minimum: 0 |
{
"input": {
"attenuationPerMeter": 1,
"minimumTransmissionFraction": 0.1353352832366127
},
"output": {
"maximumOneWayDepthMeters": 2,
"maximumRoundTripDepthMeters": 1
}
}Limitations and assumptions
No backscatter, interface loss, water composition or detector response is inferred.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Audience Safe Distance: Estimate projector distance needed to meet a caller-supplied irradiance limit. For a complementary task, use Underwater Optical Mode Comparison: Compare Beer–Lambert transmission for two underwater optical bands.
References
-
Bathymetric Penetration — tool.io
Similar or alternative tools
- Audience Safe Distance
Estimate projector distance needed to meet a caller-supplied irradiance limit.
- Underwater Optical Mode Comparison
Compare Beer–Lambert transmission for two underwater optical bands.