---
title: "Air quality: Sentinel-5P satellite observation + CAMS model (Copernicus)"
method: GET
path: "/api/v2/air-quality"
tags: ["Air Quality"]
---

# Air quality: Sentinel-5P satellite observation + CAMS model (Copernicus)

`GET /api/v2/air-quality`

Air composition at any coordinate worldwide from Copernicus, in two layers. OBSERVATION (`products`): the latest Sentinel-5P TROPOMI satellite pass - NO2, O3, CO, CH4 and the UV aerosol index as COLUMN densities (not surface, not an air-quality index), each with its observation time; often null (a polar orbiter sees a place about once a day, clouds aside). MODEL (`model`): CAMS surface concentrations in ug/m3 - a continuous field that fills those gaps - `cams_global` (PM2.5, PM10 worldwide) and `cams_european` (CO, NO2, O3, SO2, PM2.5, PM10 over Europe). Modelled estimates, not measurements. Select observation products with the `products` parameter.

## Query parameters

- `lat` number, required — Latitude, decimal degrees.
- `lon` number, required — Longitude, decimal degrees.
- `products` string, nullable — Comma-separated subset of the OBSERVATION products no2,o3,co,ch4,aer_ai (default: all). The CAMS model layer always returns its full set.

## Response `200`

Successful Response

- EnvelopeAirQualityFeed
  - `data` AirQualityFeed, required
    - `location` AirLocation, required
      - `requested` object, required — The requested lat/lon.
      - `cell` AirCell, required
        - `lat` number, required — Sampled 0.25 degree cell center latitude.
        - `lon` number, required — Sampled 0.25 degree cell center longitude.
    - `products` object, required — OBSERVATION layer - per-product latest Sentinel-5P observation within the 72 h retention window, or null when the cell has no recent quality-passing observation (clouds, night side, polar winter, or the product's coverage share of the download budget). Keys: no2, o3, co, ch4, aer_ai.
    - `model` object, required — MODEL layer - CAMS surface concentrations (ug m-3), modelled estimates not measurements. Sub-layers: `cams_global` (pm2p5, pm10; worldwide, 0.4 deg) and `cams_european` (no2, o3, co, so2, pm2p5, pm10; Europe only, 0.1 deg ensemble). A product is null when its cell has no model value (cams_european is null outside Europe, and either layer is null until ingested).
    - `coverage_note` string, nullable — Set when neither an observation nor a model value is available for this cell.
    - `attribution` object, required — Copernicus Sentinel + CAMS data credit (mandatory).
    - `methodology` string, required — How the observation layer is derived.
    - `model_methodology` string, required — How the CAMS model layer is derived.
    - `disclaimer` string, required — Observation-layer honesty discipline (column, not surface).
    - `model_disclaimer` string, required — Model-layer honesty discipline (modelled, not measured).
  - `meta` SugraMeta, required — Metadata attached to every /api/v1/* response envelope.
    - `endpoint` string, required — Requested endpoint path.
    - `data_time` string, required — ISO 8601 UTC timestamp of the source data, not of the request.
    - `response_time` string, required — ISO 8601 UTC timestamp when this response was produced.
    - `provider` string, required — API name and version.
    - `source` string, nullable — Identifier of the primary upstream source used for this response.
    - `attribution` string, nullable — Human-readable attribution mandated by an upstream source (e.g. a securities regulator or self-regulatory organization). Present only on responses whose source requires the owner and source to be clearly identified. Do not remove or alter it when using the response.
    - `fallback_used` boolean, nullable — True when the primary source failed and a fallback produced the data.
    - `fallback_chain` string[], nullable — Ordered list of sources attempted, in the order they were tried.
    - `cached` boolean, nullable — True when this response was served from the internal cache.
    - `stale` boolean, nullable — True when the cached response was returned after the upstream rate-limited or errored. Clients can use this to detect degraded data.

## Other responses

- `401` — Missing or invalid `x-api-key` header. JSON body with a stable `code` distinguishing `missing_api_key` (no header sent) from `invalid_api_key` (header sent, key not accepted); any other 401 source carries the generic `unauthorized` with its detail as `reason`. Plus `hint`. `plan` is always null on 401 - an unauthenticated request has no plan; quota exhaustion is 429, not 401.
- `422` — Validation Error
- `429` — Daily rate limit exceeded. Check `X-RateLimit-Reset` for the next window.
- `503` — Upstream source is temporarily unavailable. Retry after a short delay.

---

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