EPA Air Quality System (AQS)
The Air Quality System (AQS) is the US Environmental Protection Agency's repository of ambient air-quality monitoring data, assembled to support air quality assessments, area designations, modeling for permit review, and reports to Congress mandated by the Clean Air Act. It holds pollutant measurements from thousands of monitoring stations operated by EPA, state, local, and tribal agencies, along with meteorological data, station location information, and quality-assurance records. AQS data are exposed programmatically through a public REST API that returns JSON. AQS is an upstream data source for the KnowWhereGraph.
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