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State of California California Air Resources Board
January - July 22nd
Years 1998 - 2001 Year-to-Date Ozone Summary
for Selected California Monitoring Sites and Regions

The tables below include ozone summary statistics for 2001 through the date given above. For comparison, the 1998, 1999, and 2000 summary statistics are for the year-to-date. To view the 1998, 1999, and 2000 summary statistics for the full year, click on Full Year.

   

Previous Ozone Summaries

Greater Sacramento Planning Area
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Sacramento Folsom-
50 Natoma Street
1998 7 1 6 0.15 0.14
1999 13 3 10 0.15 0.13
2000 3 1 2 0.13 0.10
2001** 21 3 17 0.14 0.11

Sacramento Sacramento-
Del Paso Manor
1998 3 1 2 0.15 0.13
1999 5 1 3 0.13 0.11
2000 4 0 3 0.12 0.10
2001** 11 1 8 0.14 0.11

Sacramento Sloughhouse 1998 4 1 4 0.15 0.11
1999 8 2 4 0.13 0.11
2000 7 2 6 0.14 0.10
2001** 19 0 18 0.12 0.10
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Greater Sacramento Planning Area
Summary
1998 12 1 10 0.15 0.14
1999 21 4 17 0.15 0.13
2000 16 5 12 0.14 0.11
2001** 27 3 26 0.14 0.11
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Diego Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Diego Alpine-
Victoria Drive
1998 11 1 8 0.16 0.14
1999 11 0 7 0.12 0.10
2000 9 0 8 0.12 0.11
2001** 12 1 8 0.14 0.12

San Diego Escondido-
Valley Parkway
1998 1 0 1 0.11 0.09
1999 0 0 0 0.09 0.08
2000 4 0 2 0.12 0.09
2001** 2 0 0 0.11 0.08

San Diego Otay Mesa-
Paseo International
1998 0 0 0 0.09 0.08
1999 0 0 0 0.09 0.07
2000 0 0 0 0.08 0.06
2001** 0 0 0 0.08 0.07
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Diego Air Basin Summary 1998 13 1 9 0.16 0.14
1999 14 0 8 0.12 0.10
2000 13 0 11 0.12 0.11
2001** 16 1 8 0.14 0.12
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Francisco Bay Area Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Alameda Livermore-
Rincon¹
1998 4 1 2 0.15 0.11
1999 5 2 3 0.15 0.12
2000 1 1 1 0.15 0.11
2001** 7 0 2 0.11 0.09

Contra Costa Concord-
2975 Treat Blvd
1998 2 0 1 0.12 0.10
1999 2 2 2 0.16 0.12
2000 1 1 1 0.14 0.09
2001** 6 1 1 0.13 0.09

Santa Clara San Jose-
935 Piedmont Road
1998 1 1 0 0.13 0.08
1999 2 0 0 0.12 0.08
2000 1 0 0 0.10 0.07
2001** 0 0 0 0.09 0.06
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Francisco Bay Area Air Basin
Summary
1998 6 1 2 0.15 0.11
1999 6 2 3 0.16 0.12
2000 5 2 3 0.15 0.11
2001** 12 1 6 0.13 0.10
¹ The new Livermore-Rincon site, which is a replacement for the Livermore-Old 1st Street site, started operating at the begining of 2000.
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Joaquin Valley Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Fresno Clovis-
N Villa Avenue
1998 23 8 23 0.16 0.12
1999 21 1 21 0.14 0.12
2000 19 2 17 0.13 0.11
2001** 24 3 20 0.13 0.10

Fresno Fresno-
1st Street
1998 15 4 15 0.15 0.12
1999 19 2 23 0.14 0.12
2000 19 2 18 0.14 0.11
2001** 27 2 21 0.13 0.11

Fresno Parlier 1998 23 5 20 0.15 0.11
1999 27 4 26 0.16 0.11
2000 39 5 33 0.14 0.11
2001** 35 4 26 0.13 0.11

Kern Arvin-
Bear Mountain Blvd
1998 25 1 23 0.13 0.12
1999 32 1 28 0.13 0.11
2000 39 3 34 0.14 0.11
2001** 33 5 29 0.13 0.11

Kern Edison 1998 25 4 22 0.17 0.14
1999 23 0 19 0.12 0.10
2000 31 1 28 0.13 0.11
2001** 21 2 20 0.13 0.11
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Joaquin Valley Air Basin Summary 1998 36 11 32 0.17 0.14
1999 46 8 48 0.16 0.12
2000 53 8 48 0.14 0.12
2001** 49 12 46 0.13 0.12
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
South Coast Air Quality Management District
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Los Angeles Glendora-
Laurel
1998 21 7 15 0.22 0.17
1999 11 1 1 0.14 0.09
2000 15 6 11 0.17 0.15
2001** 30 6 18 0.18 0.14

Riverside Riverside-
Rubidoux
1998 26 8 20 0.19 0.17
1999 20 2 15 0.14 0.11
2000 19 1 12 0.14 0.11
2001** 24 2 20 0.13 0.12

San Bernardino Crestline 1998 44 24 39 0.24 0.21
1999 55 17 48 0.17 0.14
2000 52 11 38 0.18 0.15
2001** 50 13 45 0.17 0.13

San Bernardino Rim High School¹ 1998 48 21 47 0.24 0.21
1999 56 15 59 0.17 0.15
2000 58 14 51 0.19 0.16
2001** 40 11 40 0.16 0.13

San Bernardino San Bernardino-
4th Street
1998 28 15 16 0.21 0.18
1999 24 8 15 0.16 0.13
2000 21 3 10 0.15 0.13
2001** 27 6 22 0.15 0.13
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
South Coast Air Quality Management District Summary 1998 47 25 41 0.24 0.21
1999 59 22 53 0.17 0.14
2000 63 16 52 0.18 0.15
2001** 66 17 56 0.18 0.14
¹ The Rim High School site is a Children Health Study site, and not a South Coast SLAMS or NAMS site.
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
 
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aqdweb@cleanair.arb.ca.gov
 
This page last revised on July 23, 2001
 
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