California Air Resources Board
California Air Quality Data
California Ozone Monitoring Data

The ARB and local air pollution agencies collect and report ozone data from air pollution monitoring sites throughout California.   These data are used to measure air pollution levels and assist in determining appropriate regulatory actions.  Ozone data summaries are presented in this web site and are grouped by the following geographical areas.  To view these summaries, start by selecting the broad general area of interest to you.

California Map California Basin Map California District Map California County Map California Monitoring Site Map
Statewide Air Basin District   County   Monitoring Site  

Acknowledgement:  The local air pollution control agencies, i.e., Air Quality Management Districts (AQMDs) and Air Pollution Control Districts (APCDs), throughout the State have contributed significantly to the collection and reporting of the data contained in these pages.

Directory of Data Summaries
Statewide  Ozone Summary Graphs (Through 1995)
 Ozone Data Summaries (1980-1998)
Air Basin  Ozone Data Summaries for California Air Basins (1980-1998)
 Basin by Basin Comparison of Ozone Levels for Selected Years
 Ozone Data Summaries for Counties within each Air Basin (1980-1998)
 Ozone Data Summaries for Monitoring Sites within each Air Basin
District  Ozone Data Summaries for Air Quality Districts
 Ozone Data Summaries for Monitoring Sites within each District
County  Ozone Data Summaries for California Counties
 Ozone Data Summaries for Monitoring Sites within the County (1995-1998)
Monitoring Site  Ozone Data Summaries for Monitoring Sites (1995-1998)

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This page last revised on March 31, 1999
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