Airborne pollen / allergen forecast — six pollen types (alder, birch, grass, mugwort, olive,
ragweed) in grains/m³, each with a plain-English severity band (low / moderate / high / very
high), for a hay-fever / asthma / rhinitis audience. Returns the current hour's reading plus the
NEXT-DAY peak per type, an overall worst-case level, and a summary naming the dominant allergens.
`location` = city name or preset; EU presets carry real data (london [default], paris, berlin,
madrid, rome, amsterdam, vienna, warsaw, athens, dublin), AU/world presets (brisbane, sydney,
melbourne, perth, new york, tokyo) are convenience but normally report `coverage` =
out_of_region. Or pass explicit `lat` + `lon`. COVERAGE IS EUROPE-ONLY: the CAMS pollen model
covers Europe (~4-day forecast in season); outside Europe — including all of Australia, the
Americas, Asia, Africa — there is NO pollen model and the response says so honestly
(`coverage` = out_of_region) instead of guessing. DISTINCT from `air_quality` /
`air_quality_fusion` (those serve POLLUTANTS — PM2.5/ozone/AQI; this serves BIOLOGICAL pollen).
Source: Open-Meteo Air Quality API / Copernicus Atmosphere Monitoring Service (CAMS) European
ensemble — CC BY 4.0 under Open-Meteo's paid commercial plan (keyless to you); attribution to
Open-Meteo + CAMS carried in provenance. Informational only, not medical advice.
Every value is returned in an Ed25519-signed, provenance-stamped envelope (source and observation time) you can verify offline against /.well-known/keys, no account required.
