Great Lapse Rate / Adiabatic Cooling mechanism

Model scope

The dry approximation is standard and suitable for a simple educational or hiking/aviation tool when units and sign convention are explicit. The moist mode requires an exact nominal rate or additional atmospheric inputs before outputs can be considered uniquely correct. The existing honest label correctly acknowledges variability but does not resolve the computational ambiguity.

• The governing equation and sign convention are not explicitly stated; the standard constant-lapse approximation should be T_final = T_start - lapse_rate × altitude_change, with positive altitude_change meaning ascent.
• The dry value of 9.8 °C/km is a valid near-surface approximation to the dry-adiabatic lapse rate, but an exact dry-adiabatic temperature change requires pressure information and the relation T2 = T1 × (p2/p1)^(Rd/cp).
• The moist rate is specified only as a range of approximately 5–6 °C/km, so the instrument has no deterministic output unless it defines a specific nominal value or obtains temperature/pressure/humidity data.
• A constant moist lapse rate is not generally the standard physical calculation; the moist-adiabatic rate varies with temperature, pressure, and moisture content.

Units and conventions

• Starting temperature and resulting temperature are in °C; temperature differences in °C and K are numerically equivalent.
• Altitude change must be converted to kilometres before multiplication by the lapse rate; 1 km = 1000 m.
• Positive altitude change means ascent and cooling; negative altitude change means descent and warming.
• The test vectors use 9.8 K/km for dry air and, solely to make the ambiguous moist mode testable, a nominal 5.5 K/km moist rate.
• The lapse-rate approximation is assumed valid over the stated altitude interval.

Inspectable vector

One of 4 source-bound review vectors:

{
  "inputs": {
    "starting_temp_C": 12,
    "altitude_change": 1500,
    "altitude_unit": "m",
    "mode": "dry"
  },
  "expected_outputs": {
    "resulting_temp_C": -2.7
  },
  "working": "Convert altitude: 1500 m ÷ 1000 = 1.5 km. Cooling = 9.8 °C/km × 1.5 km = 14.7 °C. Resulting temperature = 12 °C − 14.7 °C = −2.7 °C."
}

Failure boundary

BREAK_CLAIMED · SELF_FLAGGED

The extreme altitude input produces -Infinity through JavaScript floating-point overflow instead of a rejected or physically meaningful temperature. The signed-altitude probe also exposes a potentially severe convention-dependent result.

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche5/tranche5-results.json
• BOUNDARY_HAZARD_CATALOG.json