Reference

Glossary

Plain-language definitions for every metric, abbreviation, and scoring term used across the Department Explorer and per-department pages.

Climate

Sunshine sun: Annual sunshine hours derived from the Copernicus E-OBS gridded radiation variable (QQ) using the Angström-Prescott formula (FAO-56 defaults). Population-weighted average over the department polygon. Source: E-OBS v31 + ERA5-Land, 2015–2025 window. Unit: h/yr.
Rain Comfort rain_comfort: Inverted annual count of rainy days (days with precipitation ≥ 1 mm), population-weighted. A higher score means fewer rainy days. Source: E-OBS v31 + ERA5-Land, 2015–2025 window. Unit: days/yr (raw), scored by quantile rank vs 96 departments.
Heatwaves heat_stress also: heatwave days: Days per year that fall inside a run of at least 3 consecutive days where Tmax ≥ 30 °C and Tmin ≥ 20 °C (hot day + tropical night). Equivalent to the xclim heat_wave_total_length index. Scored on an absolute scale: 0 days → 10, 12 days → 1. Neighbor-blended (70% own, 30% border-weighted neighbour average). Source: E-OBS v31 + ERA5-Land, 2015–2025 window.
Winter Mildness winter_mild: January mean daily minimum temperature (°C), population-weighted. A higher score means warmer January nights. Scored by quantile rank; neighbor-blended. Source: E-OBS TN variable, 2015–2025 window.
Mugginess muggy also: muggy days: Days per year with daily mean temperature ≥ 22 °C and relative humidity ≥ 70 % — a proxy for a humidex of roughly 30 °C or above. Scored on an absolute scale: 0 days → 10, 25 days → 1. Neighbor-blended. Note: French RH station coverage in E-OBS is thinner than for temperature or precipitation, so values carry wider uncertainty in inland areas. Source: E-OBS TG + HU, 2015–2025 window.

Lifestyle

Real Estate real_estate: Affordability score derived from the median residential price per m² in the department. Lower prices score higher. Scored on absolute thresholds. Source: DVF (Demandes de Valeurs Foncières), 2023–2025.
Tourism tourism: Annual paid lodging stays per department (hotels + campings + résidences de tourisme), in thousands of stays per year. Scored by quantile rank. A high score indicates a strong tourism ecosystem — relevant for lifestyle and potential rental income. Source: INSEE, 2024.
Pop Trend pop_trend: Inter-census annualised population growth rate (% per year) for the department, 2015–2024. A positive rate indicates net in-migration or natural growth; negative indicates decline. Scored on absolute thresholds. Source: INSEE Recensement.
Landscape landscape: Scenic and natural quality of the department. A genuine 30% editorial + 70% data composite (landscape_score field). The data 70% blends three measured components: land cover (CORINE Land Cover — share of natural land minus an artificialisation penalty, weight 0.45), relief (per-commune IGN altitudes — peak elevation + relief amplitude, weight 0.30), and protected areas (share of the department covered by IGN BDTOPO parks & nature reserves, plus a heritage bonus for Grands Sites de France and UNESCO World Heritage, weight 0.25). The editorial 30% is preserved in the landscape_editorial field so re-runs keep the curator's base. Sources: editorial + SDES CORINE Land Cover + IGN relief + IGN BDTOPO WFS protected areas.
Télétravail share teletravail: Percentage of employed residents who work without commuting (INSEE TRANS code 1, RP 2022). Caveat: this category conflates remote/WFH workers with people who work at home-premises (farmers, artisans). Rural communes legitimately read high for non-remote reasons. Displayed as context only — not a scored criterion or a filter. Source: INSEE Mobilités professionnelles RP 2022.
Self-containment self_containment: Percentage of employed residents whose workplace is in the same commune as their home. A high value suggests a self-sufficient local economy or limited commuting needs. Displayed as context only — not scored. Source: INSEE Mobilités professionnelles RP 2022.

Infrastructure

Healthcare healthcare metric: APL: Scored from the DREES APL (Accessibilité Potentielle Localisée) index, which estimates the number of general-practitioner consultations available per inhabitant per year, accounting for travel time and GP capacity. Scored on absolute thresholds; neighbor-blended. Source: DREES, 2023. Unit: consultations/inhabitant/yr.
APL: Accessibilité Potentielle Localisée. A DREES composite index measuring how accessible GPs are for a given population, factoring in the number of practising GPs within reachable distance and their appointment capacity relative to the local population's demand. Higher = better access to primary healthcare.
Schools schools metric: brevet pass rate: Scored from the brevet (Diplôme National du Brevet) pass rate — the percentage of collège students who pass the national end-of-middle-school diploma in the department. Scored on absolute thresholds. Source: DEPP (Direction de l'Évaluation, de la Prospective et de la Performance), session 2025.
Brevet: Diplôme National du Brevet (DNB). France's national collège (middle school) diploma, typically awarded at age 15. The departmental pass rate is used as a proxy for overall school quality. Source: DEPP.
Fiber fiber also: FTTH, FttH: Percentage of residential addresses in the department that are connectable to fibre-to-the-home (FTTH/FttH) broadband. Scored on absolute thresholds; neighbor-blended. Source: ARCEP (Autorité de Régulation des Communications Électroniques et des Postes) quarterly observatory, Q4 2025.
FTTH / FttH: Fibre to the Home. A broadband connection type where an optical fibre cable runs directly to the household, enabling very high speeds (typically 300 Mbit/s – 8 Gbit/s). Tracked by ARCEP in its quarterly fibre observatory.
BPE: Base Permanente des Équipements. INSEE's annual census of public and private services and amenities (schools, doctors, shops, sports facilities, …) at the commune level. Used to derive amenity scores for individual communes.
Elevation communeElevation: Mean, minimum, and maximum altitude (metres) of each commune, derived from the IGN altimetry dataset. Displayed as context on commune cards — not a scored criterion. Source: data.gouv.fr "Communes et villes de France" (Ville de Rêve / IGN), 2025 millésime.

Transport

Transport transport: A composite connectivity score that gives primary weight to whether the department has a TGV station, then blends Paris proximity: (7 if TGV else 2) + 3 × (1 − min(paris, 6.5) / 6.5), clamped to 1–10. A department with a TGV station scores 7–10 regardless of Paris distance; one without scores 2–5. Not neighbor-blended. Source: SNCF timetables 2025 + editorial.
TGV: Train à Grande Vitesse. France's high-speed rail network, operated by SNCF. Whether a department has at least one TGV station is used as a primary connectivity signal in the transport score, and also as an optional binary filter on the scorecard ("TGV only"). Source: SNCF editorial / manual station list.
Paris travel time paris: Shortest SNCF rail itinerary from the department's main TGV/Intercités station to Paris (Gare de Lyon or equivalent), in hours. Used as a component of the transport score. Source: SNCF Voyages timetables, 2025 (manual sample).

Risk & Safety

Natural Risk nat_risk: Average of the flood-risk score and the fire-risk score: round(avg(flood_risk, fire_risk)). Not neighbor-blended. A low score means high risk. Sources: BRGM Géorisques GASPAR (flood) + Copernicus CEMS Fire Weather Index (fire).
Flood risk flood_risk: Breadth of flood exposure: the share of the department's communes flagged for flooding in the BRGM Géorisques GASPAR registry — the union of the risq risk register, PPRN flood plans, and AZI flood atlases. Scored by inverted quantile across the 96 departments, so the most-exposed departments score lowest. Exposure breadth, not severity. Source: BRGM Géorisques GASPAR.
Fire risk fire_risk: Fire-WEATHER danger: the fire-season (Jun–Sep) mean of the Copernicus CEMS Fire Weather Index (FWI, ERA5 reanalysis), area-weighted over the department. It scores how favourable the weather is to fire start, spread and sustainability — not observed burns or fuel load — and covers all of France uniformly. Scored by inverted quantile across the 96 departments, so the highest-FWI Mediterranean departments score lowest (least safe). Source: Copernicus CEMS Fire Weather Index.
Safety safety: Inverted reported-crime index (offences per 1 000 inhabitants, composite of multiple offence categories). A higher safety score means lower recorded crime. Scored on absolute thresholds. Source: Ministère de l'Intérieur statistics, 2022–2023.
PPRi / PPRN: Plan de Prévention des Risques (naturels / inondation). Official French risk-zoning plans produced by the state for areas exposed to natural hazards such as flooding (PPRi) or other natural risks (PPRN). Communes included in these plans are subject to building restrictions. Sourced from BRGM Géorisques.

Data terms

DVF: Demandes de Valeurs Foncières. Open database of French real-estate transactions published by the DGFiP (Direction Générale des Finances Publiques). Contains sale prices, addresses, and property characteristics for residential and commercial transactions. Used to derive department-level median prices. License: Etalab 2.0. Vintage: 2023–2025.
EPCI: Établissement Public de Coopération Intercommunale. A grouping of neighbouring communes that pool certain services and planning powers. There are ~1,250 EPCIs in metropolitan France. The Communes Explorer uses EPCIs as its choropleth unit (currently ~200 EPCIs covered). EPCIs are an internal navigation level — they are not surfaced as a user-selectable filter in the main scoring interface.
E-OBS: Copernicus Climate Change Service (C3S) daily gridded observational dataset for Europe, produced by KNMI and partners. Provides daily temperature (mean TG, min TN, max TX), precipitation (RR), radiation (QQ), wind (FG), and relative humidity (HU) at 0.1° resolution. Version 31, supplemented with ERA5-Land for the 2025 extension. Used for all climate scores. License: CC-BY 4.0.
ARCEP: Autorité de Régulation des Communications Électroniques et des Postes. France's telecoms and postal regulator. Publishes a quarterly fibre-optic observatory with FTTH coverage at commune level — the source for the fiber/FTTH score.
DREES: Direction de la Recherche, des Études, de l'Évaluation et des Statistiques. The French ministry's statistical arm for health and social affairs. Publishes the APL healthcare accessibility index.
DEPP: Direction de l'Évaluation, de la Prospective et de la Performance. The statistical arm of the French Education Ministry. Publishes brevet (DNB) pass rates by department and the directory of accredited schools.
INSEE: Institut National de la Statistique et des Études Économiques. France's national statistics institute. Provides census data (population trends), the BPE amenities database, tourism stays, and the commute/mobility surveys (RP navettes domicile-travail) used for télétravail and self-containment figures.
Neighbor blending: Several scores are smoothed by blending a department's own value (70%) with a border-length-weighted average of its neighbours (30%). This avoids sharp cliff-edges at borders where climate or infrastructure transitions gradually. Applied to: sunshine, rain comfort, heat stress, winter mildness, mugginess, healthcare (APL), fiber. NOT applied to transport or natural risk.
100-point weight budget: The 16 scoring criteria are each assigned a weight that sums to 100 points by default. Users can redistribute those points freely on the scorecard. Default allocation: Climate 30, Lifestyle 30, Infrastructure 13, Transport 12, Risk/Safety 15.
GHSL / GHS-POP: JRC Global Human Settlement Layer population grid (R2023A, epoch 2020, 30 arcsec resolution). Used to population-weight climate metrics over each department polygon, so that dense cities dominate the department average rather than sparsely populated mountain or coastal cells.