Relative Thermal Resistance Mixing Calculator

Compute caller RTRM density contrast normalized to explicit reference contrast, retaining unstable sign; reference may reflect caller 4–5°C convention, not work/Schmidt stability or a universal mixing threshold.

Description

Relative thermal resistance normalizes a density contrast by a declared reference contrast.

Relative thermal resistance normalizes a density contrast by a declared reference contrast. Its sign retains stable versus reversed ordering.^[1]

Enter positive upper/lower densities and positive caller reference. Return signed ratio and inclusive lower≥upper ordering flag.

When to use Relative Thermal Resistance Mixing Calculator

Use Relative Thermal Resistance Mixing Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No work of mixing, Schmidt stability or universal mixing threshold is calculated.

Prepare the observed lake or sample measurements and explicit calibration, reference values or thresholds requested. Keep depth coverage, units, dates and sampling conditions consistent.

How to use Relative Thermal Resistance Mixing Calculator and understand its results

Prepare the observed lake or sample measurements and explicit calibration, reference values or thresholds requested. Keep depth coverage, units, dates and sampling conditions consistent.
Enter upperLayerDensityKgM3, lowerLayerDensityKgM3, callerReferenceDensityContrastKgM3 using the field table and calculation rules, then run the tool.
Read signedRelativeThermalResistance, stableDensityOrdering. 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
upperLayerDensityKgM3	Upper layer density kg m3	number	Required
lowerLayerDensityKgM3	Lower layer density kg m3	number	Required
callerReferenceDensityContrastKgM3	Caller reference density contrast kg m3	number	Required

Enter positive upper/lower densities and positive caller reference. Return signed ratio and inclusive lower≥upper ordering flag.

RTRM=(lowerDensity−upperDensity)/referenceContrast

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

Output field	Meaning	Value type
signedRelativeThermalResistance	Signed relative thermal resistance	number
stableDensityOrdering	Stable density ordering	boolean

json

{
  "input": {
    "upperLayerDensityKgM3": 999,
    "lowerLayerDensityKgM3": 1000,
    "callerReferenceDensityContrastKgM3": 0.2
  },
  "output": {
    "signedRelativeThermalResistance": 5,
    "stableDensityOrdering": true
  }
}

Limitations and assumptions

No work of mixing, Schmidt stability or universal mixing threshold is calculated.

Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.

Alternative or Complementary methods

Use Inverse Stratification Under Ice Checker: Under-ice inverse temperature evidence requires sampled warming with depth within 0–4°C. Measurement tolerance determines resolved change. For a complementary task, use Spring Turnover Trigger Temperature Checker: Near-isothermal temperature evidence can identify a spring-turnover candidate. Ice status and sampled reference proximity are additional gates.

References

Relative Thermal Resistance Mixing Calculator — tool.io

Similar or alternative tools

Inverse Stratification Under Ice Checker
Under-ice inverse temperature evidence requires sampled warming with depth within 0–4°C. Measurement tolerance determines resolved change.
Spring Turnover Trigger Temperature Checker
Near-isothermal temperature evidence can identify a spring-turnover candidate. Ice status and sampled reference proximity are additional gates.