Steric Sea Level Expansion Contribution

Compute exact mass-conserving layer stretching from paired density states; includes combined density effects, unlike first-order thermal-only anomaly, and excludes mass loading.

Description

Fixed-mass layers stretch when density decreases and contract when it increases.

Fixed-mass layers stretch when density decreases and contract when it increases. This density-ratio calculation includes all supplied density effects.

Compute exact mass-conserving layer stretching from paired density states; includes combined density effects, unlike first-order thermal-only anomaly, and excludes mass loading.

When to use Steric Sea Level Expansion Contribution

Use this tool to compute exact mass-conserving layer stretching from paired density states; includes combined density effects, unlike first-order thermal-only anomaly, and excludes mass loading.

Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.

How to use Steric Sea Level Expansion Contribution and understand its results

Gather the water, wave, current or profile observations and any supplied calibration constants. Confirm units and the stated coordinate and pressure conventions.
Enter referenceLayerThicknessesM, referenceDensitiesKgPerM3, observedDensitiesKgPerM3 using the field table and calculation rules, then run the tool.
Read layerStericChangesM, totalStericSeaLevelChangeM. 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
referenceLayerThicknessesM	Reference layer thicknesses m	list of number	Required
referenceDensitiesKgPerM3	Reference densities kg per m3	list of number	Required
observedDensitiesKgPerM3	Observed densities kg per m3	list of number	Required

Align nonnegative reference thicknesses with positive reference and observed densities. Return signed local changes and their sum.^[1]

Paired lists must be nonempty and have equal lengths.

layer change = reference thickness × (reference density/observed density − 1)

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

Output field	Meaning	Value type
layerStericChangesM	Layer steric changes m	list of number
totalStericSeaLevelChangeM	Total steric sea level change m	number

json

{
  "input": {
    "referenceLayerThicknessesM": [
      10,
      20
    ],
    "referenceDensitiesKgPerM3": [
      1000,
      1000
    ],
    "observedDensitiesKgPerM3": [
      990,
      1010
    ]
  },
  "output": {
    "layerStericChangesM": [
      0.10101010101010101,
      -0.19801980198019803
    ],
    "totalStericSeaLevelChangeM": -0.09700970097009702
  }
}

Limitations and assumptions

Mass loading is excluded; density effects need not be thermal alone.

Numbers and computed results must be finite; overflow produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Thermosteric Anomaly Component: Integrate signed small-anomaly thermal expansion over caller layers; holds salinity/mass fixed and differs from exact density-ratio steric stretching. For a complementary task, use Haline Contraction Beta Seawater: Infer signed haline contraction from a supplied density/salinity regression at fixed temperature/pressure; thermal expansion uses a different fixed-property bracket experiment.

References

Steric Sea Level Expansion Contribution — tool.io

Similar or alternative tools

Thermosteric Anomaly Component
Integrate signed small-anomaly thermal expansion over caller layers; holds salinity/mass fixed and differs from exact density-ratio steric stretching.
Haline Contraction Beta Seawater
Infer signed haline contraction from a supplied density/salinity regression at fixed temperature/pressure; thermal expansion uses a different fixed-property bracket experiment.