Active Crown Fire Spotting Distance Calculator
Audit already observed crown-fire ember segment residence/wind advection against independent spot distance; no plume rise, ember launch, maximum safe distance or tactical forecast. Caller independently verifies units, applicability and matching conditions; no operational recipe, safety certification, causal efficacy or legal/resource classification is inferred.
Description
Integrating horizontal wind over an independently sampled ember flight time gives a conditional advection displacement.
Integrating horizontal wind over an independently sampled ember flight time gives a conditional advection displacement.1
A signed coordinate convention matters, and wind-only displacement does not model lofting, turbulence or viable spotting. Use this tool to calculate active crown fire spotting distance from the supplied measurements and assumptions.
When to use Active Crown Fire Spotting Distance Calculator
Use this tool to calculate active crown fire spotting distance from the supplied measurements and assumptions. Establish the species/site, survey protocol, units, sampled area or exposure, and the independently chosen reference or model.
How to use Active Crown Fire Spotting Distance Calculator and understand its results
- Establish the species/site, survey protocol, units, sampled area or exposure, and the independently chosen reference or model.
- Enter observedEmberFlightSegmentSeconds, observedMatchedHorizontalWindMSecond, observedIndependentSpotDistanceM, using the field meanings and rules below, then run the tool.
- Read observedAdvectiveSpotDistanceM, signedSpotMinusAdvectionM. Interpret the fields using their units, signs and evidence conventions below.
- If input validation fails, correct the reported field and run again. Before applying the result, check reference scope, model assumptions and any missing evidence or placeholder values.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedEmberFlightSegmentSeconds | Observed ember flight segment seconds | list of number | Required |
| observedMatchedHorizontalWindMSecond | Observed matched horizontal wind m second | list of number | Required |
| observedIndependentSpotDistanceM | Observed independent spot distance m | number | Required |
Enter nonempty aligned positive flight-interval seconds and finite signed horizontal wind speeds, with nonnegative observed spotting distance in meters. Sum time×wind for signed conditional displacement and subtract it from observed distance. Negative advection is retained under the declared axis; no ember trajectory or ignition outcome is modeled.
advectionM=Σseconds_i×windMPerSecond_i; residualM=observedSpottingM−advectionM Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| observedAdvectiveSpotDistanceM | Observed Advective Spot Distance M; follow the units, sign, ordering and evidence convention stated above | number |
| signedSpotMinusAdvectionM | Signed Spot Minus Advection M; follow the units, sign, ordering and evidence convention stated above | number |
{
"input": {
"observedEmberFlightSegmentSeconds": [
2,
3
],
"observedMatchedHorizontalWindMSecond": [
1,
2
],
"observedIndependentSpotDistanceM": 10
},
"output": {
"observedAdvectiveSpotDistanceM": 8,
"signedSpotMinusAdvectionM": 2
}
}Limitations and assumptions
A signed coordinate convention matters, and wind-only displacement does not model lofting, turbulence or viable spotting. Interpretation depends on the units, sampling scope and exact model described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse evidence arrays fail validation; the specific bounds and alignment requirements are stated above. Extremely large inputs or outputs can also be rejected. An input error is distinct from a successful result reporting false, no matches or missing evidence.
Alternative or Complementary methods
Use Slope Factor Rate of Spread Cosine Calculator for this related task: Along-slope distance and horizontal distance differ by the cosine of slope angle.
Use Rothermel Surface Rate of Spread Calculator when its separate inputs and assumptions fit the question: A Rothermel-style spread relation balances reaction intensity and propagation factors against the energy needed to heat fuel.
References
Similar or alternative tools
- Slope Factor Rate of Spread Cosine Calculator
Along-slope distance and horizontal distance differ by the cosine of slope angle.
- Rothermel Surface Rate of Spread Calculator
A Rothermel-style spread relation balances reaction intensity and propagation factors against the energy needed to heat fuel.