OpenAQ
OpenAQ is a non-profit platform that gathers publicly available air quality measurements from government monitoring networks, research groups and air-sensor providers into one open API. Through ScholarMuse an agent can give a latitude, a longitude and a date range and get back the nearest stations within 25 km, each with its daily mean, minimum and maximum for the pollutants it measures.
ScholarMuse tools: get_air_quality. Each successful call uses credits.
Ask your agent
What your agent gets back
Every record carries id, source, title, url, license, attribution and retrievedAt. The fields below are the data that comes from OpenAQ.
get_air_quality
One record per station, nearest first, at most three per call. The series sit in measurements: one entry per pollutant sensor, each with its own observations.
- name
- Station name, with locality when OpenAQ has one
- country
- Two-letter country code
- latitude, longitude
- Position of the station
- distanceKm
- Distance from the requested point in km
- provider
- Network or service the data comes through, e.g. London Air Quality Network
- owner
- Owner of the station as OpenAQ lists it
- referenceGrade
- True for a reference-grade monitor, false for an air sensor
- licenses
- Licence names attached to the station; can be empty
- licenseAttribution
- Who to credit under that licence, when given
- firstMeasurement, lastMeasurement
- First and latest reading OpenAQ holds for the station (UTC)
- start, end
- The date range requested
- measurements[].pollutant
- pm25, pm10, no2, o3, so2 or co
- measurements[].units
- Units reported by the sensor, e.g. µg/m³
- measurements[].sensorId
- OpenAQ sensor id
- measurements[].statistic
- Always daily mean
- measurements[].observations
- Rows of date, value (the daily mean), min, max and coveragePercent
What it covers
- Fixed stations that report to OpenAQ. Its API listed 159 countries and 173 data providers on 13 October 2026. Coverage depends on where stations exist: dense in many cities, absent in many rural and remote areas.
- Six pollutants: PM2.5, PM10, NO2, O3, SO2 and CO. Ask for all of them or name the ones you need.
- The three nearest stations that measure a requested pollutant, within a radius you set (25 km by default and at most). Stations that were still reporting in the requested period are preferred.
- Daily means with each day's minimum, maximum and percentage of expected readings, for a date range of up to 366 days. Without dates, the last 7 days are returned.
Limits
- Measured data only. There are no forecasts, no modelled or satellite values, no air quality index and no interpolation between stations: with no station within 25 km, the result is empty.
- Daily means only, not hourly readings. Mobile monitors are left out, and so are the other parameters OpenAQ holds, such as black carbon, PM1, temperature and humidity.
- Values are passed on as the station reported them, without quality control. Reference monitors and low-cost sensors appear side by side (see referenceGrade), and faulty readings such as negative concentrations are not removed. Check coveragePercent before using a day.
- A listed station can come back with no observations for the period, for example when it started later or has a gap.
- Units come from each sensor. Read them with every series instead of assuming one unit per pollutant.
- One point per call. A call makes one upstream request per pollutant sensor, about one per second, so asking for all six pollutants can take 15 seconds or more.
How ScholarMuse reaches OpenAQ
The connector calls the OpenAQ API at api.openaq.org/v3 with ScholarMuse's own API key in the X-API-Key header: /locations to find the stations around the point, then /sensors/{id}/days for each pollutant sensor. Without a configured key the tool is not offered at all.
The station list is cached for up to 6 hours and daily values for up to 1 hour, so the latest day can lag OpenAQ by that long.
API key: the upstream API needs one; ScholarMuse uses its own, so you do not add one.
Licence and attribution
Licence: Varies by data provider (many CC BY 4.0); see each station
Air quality data from OpenAQ (openaq.org) and the original monitoring agencies listed with each station.
Each record carries the licence of its own station (for example the UK Open Government Licence or CC BY 4.0) and an attribution line that names the station’s licence holder or provider, followed by “via OpenAQ (openaq.org)”. The licence above is used when a station lists none. When you cite the data in a paper, follow OpenAQ's own citation guidance.
