Crown Closure Percentage Calculator
Audit actual solid-angle sky closure with weighted assessed/unassessed hemispherical samples, not projected canopy ground area or gap fraction alone. Caller independently verifies units, applicability and matching conditions; no operational recipe, safety certification, causal efficacy or legal/resource classification is inferred.
Description
Crown closure uses independently annotated sky obstruction under a sampling design.
Crown closure uses independently annotated sky obstruction under a sampling design.1
Weighting known observations retains missing coverage without treating unobserved points as open sky. Use this tool to calculate crown closure percentage from the supplied measurements and assumptions.
When to use Crown Closure Percentage Calculator
Use this tool to calculate crown closure percentage 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 Crown Closure Percentage Calculator and understand its results
- Establish the species/site, survey protocol, units, sampled area or exposure, and the independently chosen reference or model.
- Enter observedSkyOccludedFlags, observedSolidAngleWeights, knownSkyAssessmentFlags, using the field meanings and rules below, then run the tool.
- Read knownSolidAngleCrownClosureFraction, unassessedSolidAngleFraction. 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 |
|---|---|---|---|
| observedSkyOccludedFlags | Observed sky occluded flags; binary 0/1 under the definitions below | list of number | Required |
| observedSolidAngleWeights | Observed solid angle weights | list of number | Required |
| knownSkyAssessmentFlags | Known sky assessment flags; binary 1=known, 0=unknown, in the order described below | list of number | Required |
Enter nonempty aligned nonnegative observation weights and binary canopy-occluded and known flags. Require positive total weight and positive known weight. Divide known occluded weight by known weight and report unknown weight/total weight. Return fractions rather than percentages; unknown observations are not counted as clear sky.
closureFraction=Σweight×occluded×known/Σweight×known; unknownFraction=Σweight×(1−known)/Σweight Use the exact units, boundary rules, ordering and missing-evidence conventions above.
| Output field | Meaning | Value type |
|---|---|---|
| knownSolidAngleCrownClosureFraction | Known Solid Angle Crown Closure Fraction; follow the units, sign, ordering and evidence convention stated above | number |
| unassessedSolidAngleFraction | Unassessed Solid Angle Fraction; follow the units, sign, ordering and evidence convention stated above | number |
{
"input": {
"observedSkyOccludedFlags": [
1,
0,
1
],
"observedSolidAngleWeights": [
1,
2,
1
],
"knownSkyAssessmentFlags": [
1,
1,
0
]
},
"output": {
"knownSolidAngleCrownClosureFraction": 0.3333333333333333,
"unassessedSolidAngleFraction": 0.25
}
}Limitations and assumptions
Weighting known observations retains missing coverage without treating unobserved points as open sky. 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 Foliage Height Diversity Index Calculator for this related task: Vertical foliage diversity summarizes how measured foliage is distributed among chosen height bins.
Use Silvopasture Shade Percent Heat Stress Relief when its separate inputs and assumptions fit the question: A shade-temperature mixture weights shaded and sun-exposed temperatures by the observed shaded fraction.
References
-
Crown Closure Percentage Calculator — tool.io
Similar or alternative tools
- Foliage Height Diversity Index Calculator
Vertical foliage diversity summarizes how measured foliage is distributed among chosen height bins.
- Silvopasture Shade Percent Heat Stress Relief
A shade-temperature mixture weights shaded and sun-exposed temperatures by the observed shaded fraction.