Snout Recession Length Per Decade Calculator

Integrate exact caller decade windows using interpolation only within observed snout positions, reporting actual displacement per decade; no rescaling a short rate to unobserved ten-year periods.

Description

An observed decade recession uses positions at both ends of a complete ten-year window.

An observed decade recession uses positions at both ends of a complete ten-year window. Short-term rates are not rescaled beyond coverage.^[1]

Enter aligned finite positions/at least two strictly increasing years and safe-integer decade starts. Interpolate both endpoints within observed range; return signed m/decade. Empty requested windows are allowed.

When to use Snout Recession Length Per Decade Calculator

Use Snout Recession Length Per Decade Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No extrapolation or unobserved ten-year behavior is inferred.

Prepare the observed ice, snow, water or geometry measurements and explicit calibration parameters requested. Keep coordinates, datum, density and time units consistent.

How to use Snout Recession Length Per Decade Calculator and understand its results

Prepare the observed ice, snow, water or geometry measurements and explicit calibration parameters requested. Keep coordinates, datum, density and time units consistent.
Enter observationYears, outwardSnoutPositionsM, decadeStartYears using the field table and calculation rules, then run the tool.
Read observedInterpolatedRecessionMPerDecade. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
observationYears	Observation years	list of number	Required
outwardSnoutPositionsM	Outward snout positions m	list of number	Required
decadeStartYears	Decade start years	list of number	Required

recession=interpolated outwardPosition(year)−position(year+10)

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
observedInterpolatedRecessionMPerDecade	Observed interpolated recession m per decade	list of number

json

{
  "input": {
    "observationYears": [
      2000,
      2005,
      2010,
      2020
    ],
    "outwardSnoutPositionsM": [
      1000,
      900,
      800,
      500
    ],
    "decadeStartYears": [
      2000,
      2010
    ]
  },
  "output": {
    "observedInterpolatedRecessionMPerDecade": [
      200,
      300
    ]
  }
}

Limitations and assumptions

No extrapolation or unobserved ten-year behavior is inferred.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Surge Front Advance Rate Calculator: A surge-activation front is a tracked threshold location. Its motion differs from the velocity of individual ice particles. For a complementary task, use Moraine Position Recession Rate Calculator: Dated moraine positions can support an interval-average historical recession estimate. Ages before present decrease toward the younger marker.

References

Snout Recession Length Per Decade Calculator — tool.io

Similar or alternative tools

Surge Front Advance Rate Calculator
A surge-activation front is a tracked threshold location. Its motion differs from the velocity of individual ice particles.
Moraine Position Recession Rate Calculator
Dated moraine positions can support an interval-average historical recession estimate. Ages before present decrease toward the younger marker.