Beaufort-to-Wave-Height Sea State

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Earth & Space (astronomy, orbital mechanics, meteorology, geology, geodesy, oceanography)

Tranche

tranche-7

Evidence ID

t7-117

Ledger rows

1

No ledger note is attached.

Review findings

The honest-label warning is appropriate but should be strengthened: this is a wind-to-typical-sea-state estimate, not a deterministic wave-height measurement. The specification needs an explicit, authoritative Beaufort-to-wave-height convention, a stated WMO table edition or source, the meaning of wave height, and exact wind-speed boundary rules before it can receive PASS. The fourth vector demonstrates that rounded km/h Beaufort tables and exact knot-converted thresholds disagree at 20 km/h; this ambiguity must be resolved in the implementation.

Formula and scope findings

• The WMO sea-state code table is indexed by observed sea-state code 0–9, not directly by Beaufort force 0–12; the specification does not define the required Beaufort-to-sea-state mapping.
• A one-to-one mapping of Beaufort number to WMO sea-state code is not a standard physical relationship. Beaufort force describes wind, whereas sea state depends strongly on fetch, wind duration, swell, and local conditions.
• The claimed output should identify the wave-height quantity as a typical significant wave-height range, if that is the intended WMO convention; individual wave heights can be substantially different.
• Beaufort-force conversion from wind speed needs a specified convention, including wind measurement height, averaging interval, and unit thresholds.
• The table has no defined behavior for Beaufort forces 10–12 if the implementation assumes a WMO sea-state-code index, because WMO sea-state codes stop at 9.

Unit assumptions

• Wave-height ranges are in metres and are interpreted as typical significant wave-height ranges.
• Wind speed, when supplied in knots or km/h, is assumed to be a 10 m wind averaged over the standard Beaufort observation interval; this convention is not stated in the specification.
• For the test vectors below, Beaufort thresholds use the widely tabulated standard Beaufort scale: force 0 is 0–1 kt, force 3 is 7–10 kt, and force 4 is 11–16 kt.
• The test vectors explicitly use the provisional implementation assumption that Beaufort force N maps to WMO sea-state code N for N=0–9. This is a lookup convention for testing, not a generally valid oceanographic law.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

The lookup has an undefined out-of-domain input at Beaufort 13, which must be rejected, and an unlabeled wind-speed value such as 10 produces materially different results depending on whether it means m/s or km/h.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "beaufort_number": 0
  },
  "expected_outputs": {
    "wave_height_range_m": {
      "minimum": 0,
      "maximum": 0
    },
    "sea_state_description": "Calm (glassy)",
    "wmo_sea_state_code": 0
  },
  "reference_data": {
    "wmo_sea_state_code": 0,
    "wave_height_range_m": [
      0,
      0
    ],
    "description": "Calm (glassy)",
    "source_convention": "WMO standard sea-state code table, widely tabulated standard value",
    "beaufort_to_sea_state_assumption": "Beaufort 0 -> WMO sea-state code 0; provisional identity mapping"
  },
  "working": "1. Read Beaufort number: B=0.\n2. Apply the stated test convention: sea-state code = B = 0.\n3. WMO code 0 gives wave-height range 0.0–0.0 m.\n4. Therefore the expected output is 0.0–0.0 m, Calm (glassy)."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

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

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche7/tranche7-results.json
• BOUNDARY_HAZARD_CATALOG.json