One figure, five measured signals
Per zone (a k-anonymised grid cell or named region) the index folds five sub-indices, each in 0–100, by published weights. The overall index is the session-weighted mean across released zones. Sub-indices that lack data are renormalised out — never silently zeroed — and the methodology block records which were present.
| Sub-index | Weight | What it measures |
|---|---|---|
| Carbon-neutral share | 0.35 | Neutral ÷ (neutral + carbon-positive) sessions. Measured, not modelled. |
| Electrification | 0.20 | Electric ÷ (electric + combustion) equipment; falls back to neutral share when absent. |
| Seasonal spread | 0.15 | 1 − concentration (Herfindahl over months) — rewards year-round, low-pressure use. |
| Protected-area pressure | 0.15 | Inverse of MPA-proximate session density vs a capacity reference (PostGIS). |
| Consent coverage | 0.15 | Research-eligible ÷ total sessions — transparency of the underlying cohort. |
How it is computed
The numbers are recomputed from the audit log; a runs table is a snapshot + publish ledger, not the source of truth. Zones below k ≥ 10 distinct contributors are suppressed. Each published run carries a versioned methodology block (weights, per-sub formulas, k-threshold, present sub-indices).
Publishing is always a manual ops action — a human signs off the public figure. Every artifact carries a reproducible provenance block: a SHA-256 cohort hash, N, distinct-contributor count, data lag and the methodology version.
What is measured vs modelled
Carbon-neutral vs carbon-positive session counts, electric-vs-combustion mix, seasonal intensity, protected-area density, consent coverage. Counts of real sessions — no model, no calibration needed.
The suitability scores and any energy proxy derive from expert-set, not-yet-calibrated curves. Every artifact carries a maturity banner; no "verified" wording until the data earns it.
Sold to operators, given to regulators
Compliance pack (sold)
A framework-mapped export (CSRD / GRI / GSTC / Travelife / Blue Flag) from the same aggregates, per-tenant or platform-wide. Plan-gated to Pro and above.
Annual index (given)
The latest published platform figure is free, CC BY 4.0, citable — the credibility moat. Openness is the point.