Sources and method

Below is exactly where the data on these maps comes from, how often it is updated and which choices we make to filter out false reports. That way you can judge for yourself how much weight to give the information.

Sources used

• NASA FIRMS (VIIRS) — thermal detections from the NOAA-20, NOAA-21 and Suomi-NPP satellites, at a resolution of roughly 375 metres per pixel. This is the basis of every dot on the map. firms.modaps.eosdis.nasa.gov
• Copernicus EFFIS — the European Forest Fire Information System. We use it as an independent check: if a detection falls within roughly 2.5 kilometres and 36 hours of an EFFIS report, it gets a green verification marker. forest-fire.emergency.copernicus.eu
• National and regional reports — official statements from fire services and authorities plus reliable local media, used for the news articles and to add context to major fires on the map.
• OpenStreetMap for the map background, Esri World Imagery for the satellite layer and Nominatim for place-name search.

How current the map is

The satellites pass over Europe several times a day. After an overpass it usually takes a few hours before the measurement is available. The maps refresh automatically at regular intervals, and the "Refresh live" button fetches the latest state immediately. The time of the last data fetch is always shown above the map.

How we filter false reports

• Known permanent heat sources — refineries, steel plants, oil fields, gas flares, landfills and large solar farms across Europe — are excluded.
• Isolated single measurements with no nearby detections are flagged as probably false instead of quietly disappearing; you can show or hide them with a toggle.
• You can filter by size yourself, so you only see the larger fires with several detections in the same place.
• Areas that visitors or emergency services report as structurally misrepresented are blocked manually. Such a block expires automatically, so a real fire becomes visible again later.

Limits of the data

Dense smoke and cloud can hide a fire from the satellite. Fires smaller than roughly half a hectare often go unnoticed, and hours can pass between two overpasses. An empty map therefore does not mean there is no fire anywhere. Use this site as a supplement to the official warning systems, never as a replacement.

Reporting errors

Do you see a dot that is not a fire, or is a fire missing? Report it via the contact page. More about the background of the site is on About us.