Runoff Coefficient Regional Estimate Lookup
Pool observed runoff over matched rain-volume exposure. Ratios above one are preserved rather than clamped because stored water or other inflows may contribute. Requires independently matched catchment windows; not a fixed regional coefficient or forecast.
Description
An observed runoff coefficient compares matched runoff and rainfall volumes.
An observed runoff coefficient compares matched runoff and rainfall volumes.1
Pooled volume ratios differ from equal-weight averages of event ratios and need a consistent catchment scope. Use Runoff Coefficient Regional Estimate Lookup to evaluate the supplied inputs under the model explained below.
When to use Runoff Coefficient Regional Estimate Lookup
Use Runoff Coefficient Regional Estimate Lookup to evaluate the supplied inputs under the model explained below. Establish the units, measurement scope and model assumptions before entering values.
How to use Runoff Coefficient Regional Estimate Lookup and understand its results
- Establish the units, measurement scope and model assumptions before entering values.
- Enter Observed matched runoff volumes m3, Observed matched rain volumes m3 using the field table and validation rules below, then run the tool.
- Read Pooled observed runoff coefficient; interpret the units, signs, ordering and unknown-value placeholders described below.
- Correct reported input errors and rerun. Apply successful results according to their specific meanings and check the assumptions before using them in a decision.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedMatchedRunoffVolumesM3 | Observed matched runoff volumes m3 | array of number | Required; constraints below |
| observedMatchedRainVolumesM3 | Observed matched rain volumes m3 | array of number | Required; constraints below |
Enter aligned nonempty nonnegative runoff volumes and strictly positive matched rain volumes in m³. Divide total runoff by total rain to return a dimensionless pooled coefficient. The tool does not constrain this ratio to 1, so inconsistent or differently scoped observations can return larger values. No regional coefficient table or catchment simulation is supplied.
pooledCoefficient = ΣrunoffM3/ΣrainM3 Use the field order, units and branch conditions described above.
| Output field | Meaning | Value type |
|---|---|---|
| pooledObservedRunoffCoefficient | Pooled observed runoff coefficient | number |
{
"input": {
"observedMatchedRunoffVolumesM3": [
2,
3
],
"observedMatchedRainVolumesM3": [
10,
20
]
},
"output": {
"pooledObservedRunoffCoefficient": 0.16666666666666666
}
}Limitations and assumptions
Pooled volume ratios differ from equal-weight averages of event ratios and need a consistent catchment scope. Apply the exact scope and assumptions explained above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are explained above; extremely large inputs or outputs can also be rejected. Input errors differ from successful false results, empty match lists and unknown-evidence placeholders.
Alternative or Complementary methods
Use Backfill Volume With Compaction Calculator for a related task: Compacted fill volume and loose supply volume use different material states.
Use Turc Irrigation Need Calculator for a related task: A Turc-style reference evapotranspiration estimate combines temperature, radiation and humidity.
References
Similar or alternative tools
- Backfill Volume With Compaction Calculator
Compacted fill volume and loose supply volume use different material states.
- Turc Irrigation Need Calculator
A Turc-style reference evapotranspiration estimate combines temperature, radiation and humidity.