Description
Return second-first, subtract signed pinMovement for correctedErosion, and divide by years.
Landform change is often summarized by differences in height, area, volume, or storage over a defined interval. A signed budget preserves gains and losses, but its meaning depends on a common spatial support and reference surface.
Return second-first, subtract signed pinMovement for correctedErosion, and divide by years.
When to use this tool
Use Erosion Pin Reference Exposure Delta when you need a local geomorphic change or storage-budget calculation.
How to use the tool and how it works
- Enter firstExposure, secondExposure, pinMovement, years. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read rawExposureChange, correctedErosion, erosionRate. Use the output convention below.
Require nonnegative first and second exposure and positive years. Return second-first, subtract signed pinMovement for correctedErosion, and divide by years.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstExposure | First Exposure | Required. Finite number; minimum 0. |
| secondExposure | Second Exposure | Required. Finite number; minimum 0. |
| pinMovement | Pin Movement | Required. Finite number. |
| years | Years | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| rawExposureChange | Raw Exposure Change | Required. Finite number. |
| correctedErosion | Corrected Erosion | Required. Finite number. |
| erosionRate | Erosion Rate | Required. Finite number. |
{
"input": {
"firstExposure": 10,
"secondExposure": 15,
"pinMovement": 1,
"years": 2
},
"output": {
"rawExposureChange": 5,
"correctedErosion": 4,
"erosionRate": 2
}
}Limitations and assumptions
- Lengths share units and pin movement follows the supplied exposure-error sign; negative erosion is retained without validating reference stability, actual erosion, or future rates.
- 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
Compare aligned surveys and their uncertainty over the same spatial support. A full mass or volume balance should include omitted fluxes, evolving geometry, and measurement error.
References
Similar or alternative tools
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