Mother Earth · Weather Control

Overall European AQI · Top 20: the Open-Meteo hourly formula, using the EEA bands revised in 2024, is applied to PM2.5, PM10, NO₂, O₃ and SO₂ in this common global model snapshot. Each sub-index is interpolated between its concentration thresholds; above the last threshold, the final segment is extrapolated. The largest of the five is the cell’s overall index. A country is ranked by its highest cell with all five inputs available; missing components are excluded, not replaced with zero. Equal values retain grid order. The main driver identifies the highest sub-index. This dimensionless index has no concentration unit, additive country share or chemical composition. The local comparison uses hourly point-API values and can show a different valid time or interpolation between native global timesteps, so its value can differ. Index formula and thresholds ↗.

What is ranked: the eight concentration fields PM2.5, PM10, ozone, nitrogen dioxide, sulphur dioxide, carbon monoxide, mineral dust and formaldehyde. All 900 × 451 global grid cells are evaluated from one completed CAMS run, using the latest common three-hour pollutant timestep at or before the present. The ten displayed countries have the highest country peaks, descending. Every country has one entry per agent, even if it contains several distant hotspots. Raw-value ties use grid index. These are model estimates, not city monitoring stations.

Country groups: each grid cell is assigned once by its centre to the existing Natural Earth 1:110m country polygons. All available cells assigned to a country form its group. This country grouping replaces the earlier 200 km circles. The simplified map represents 176 countries and territories on this 0.4° grid; small islands, borders and coasts are approximate, and some countries have no represented cell. Antarctica, ocean and unmapped cells do not receive country ranks, but their available readings remain in the Earth-wide denominator. Country shares describe mapped cells, not precise national inventories.

Hottest spot: coordinates identify the country’s highest available model grid cell. Natural Earth 1:10m populated places provides the nearest named city or town within the same mapped country, with the great-circle distance shown. The name is a geographic reference; the peak may be in a remote area, away from that town. Where no named place is available, exact coordinates remain visible. Choosing a row opens the peak coordinates in the local comparison alongside Costa Teguise. Hover or focus for the area-weighted country mean and available cell count. CSV exports include country identity, peak, nearest place, distance, coordinates, country mean, mapped coverage and country shares.

Consistent model for global rankings: all eight widgets use the 45 km CAMS composition grid. The Open-Meteo point service used by the local comparison combines that grid with the 11 km CAMS greenhouse-gas model for carbon monoxide and methane, so its CO values can differ from the global widget. Methane remains available in the existing local chart and watchers; it is not one of these eight global widgets. See the Open-Meteo model configuration ↗.

Percentage denominator: for each agent separately, country share = 100 × Σ(Cᵢ × Aᵢ for available cells assigned to this country) / Σ(Cⱼ × Aⱼ for all available Earth cells). C is modelled surface concentration and A is spherical grid-cell area in km², using latitude strip boundaries and half-height polar rows. The denominator includes all available land and ocean cells, not just the ten countries. It is a surface concentration integral (μg/m³ × km²), not atmospheric mass or emissions. Country mean = its integral / its available mapped area. A † percentage uses only the covered grid; missing-cell count and Earth area coverage are shown, and the CSV includes each country’s mapped coverage. PM2.5 overlaps PM10, and dust overlaps particulate matter; do not add shares across agents.

Data quality: the reader verifies grid dimensions, coordinate reference system, units and both run/valid timestamps before accepting data. Negative or infinite concentrations are rejected; missing values remain missing. A partial grid is clearly labelled: its covered-grid shares are available, while its complete worldwide total, worldwide shares and definitive country top 10 remain unavailable. The CSV distinguishes worldwide and covered-grid percentages. All eight fields update together, so the widgets never mix timestamps. Ranks use unrounded concentrations; tied values retain grid order. Percentages use four decimal places. Zero totals have no defined percentage.

Refresh: checks follow the 5–60 minute setting and Pause control above while this tab is visible. Global data loads when this section approaches the screen. A repeated snapshot is reused; the grid is downloaded again only when its run or valid time changes. CAMS model runs arrive about every 12 hours. Global results use native three-hour timesteps, independent of the local chart’s range and interpolated 15-minute display. Global timestamps are UTC. Snapshots over six hours old are marked outdated. A failed refresh preserves the last validated snapshot and its original timestamps.

References: Open-Meteo open-data distribution ↗ · Copernicus CAMS global forecasts ↗ · Live run metadata ↗ · Natural Earth country boundaries ↗ · Named places ↗ · Reader licence & source.