Description
Calculate a supplied depth-weighted water-column mean.
Aquatic measurements depend on depth datums, effective sampling area, layer weights and concentration definitions. Secchi pair averages differ from a full optical model, and particulate-by-difference values depend on comparable total/dissolved measurements. A nominal rectangular sampling volume does not establish actual filtered effort or detection.
Calculate a supplied depth-weighted water-column mean.
When to use this tool
Use Water Column Layer Average when you already have values, layerThicknesses and need to calculate a supplied depth-weighted water-column mean.
How to use the tool and how it works
- Enter values, layerThicknesses. Follow any array-alignment requirements below. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read depthWeightedAverage, totalDepth. Use the output convention below.
Require nonempty aligned arrays, nonnegative thicknesses and a positive finite thickness sum; sum value*(thickness/totalDepth) and return totalDepth.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| values | Values | Required. Array of finite number; maximum items 256. |
| layerThicknesses | Nonnegative layer weights aligned with values; zero-thickness layers contribute zero and finite total depth must be positive. | Required. Array of finite number; maximum items 256. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| depthWeightedAverage | Depth Weighted Average | Required. Finite number. |
| totalDepth | Total Depth | Required. Finite number. |
{
"input": {
"values": [
10,
20
],
"layerThicknesses": [
2,
3
]
},
"output": {
"depthWeightedAverage": 16,
"totalDepth": 5
}
}Limitations and assumptions
- Zero-thickness layers contribute zero. The values must represent comparable layer means; no profile interpolation, uncertainty or observed water-column state is inferred.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Review original field and laboratory records with the complete survey or process model. Include calibration, temporal coverage, sampling efficiency and uncertainty when local rates, depth shifts or labels cannot establish the aquatic quantity of interest.
References
Similar or alternative tools
- Secchi Pair Midpoint
Average supplied Secchi disappearance and reappearance depths.
- Lake Thermal Interface Depth Gap
Compare supplied lower and upper interface depths.