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State of California California Air Resources Board
January - August 5th
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 13 5 12 0.15 0.14
1999 13 3 10 0.15 0.13
2000 5 1 4 0.13 0.10
2001** 21 3 17 0.14 0.11

Sacramento Sacramento-
Del Paso Manor
1998 7 4 4 0.16 0.13
1999 5 1 3 0.13 0.11
2000 9 0 6 0.12 0.10
2001** 11 1 8 0.14 0.11

Sacramento Sloughhouse 1998 12 3 10 0.15 0.11
1999 8 2 4 0.13 0.11
2000 15 3 12 0.14 0.11
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 22 5 17 0.16 0.14
1999 21 4 18 0.15 0.13
2000 27 6 22 0.14 0.11
2001** 33 3 30 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 20 5 15 0.16 0.14
1999 12 0 7 0.12 0.10
2000 13 0 9 0.12 0.11
2001** 15 1 9 0.14 0.12

San Diego Escondido-
Valley Parkway
1998 4 0 3 0.12 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 22 5 16 0.16 0.14
1999 15 0 8 0.12 0.10
2000 17 0 12 0.12 0.11
2001** 19 1 9 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 10 2 4 0.15 0.11
1999 5 2 3 0.15 0.12
2000 4 1 2 0.15 0.11
2001** 7 0 2 0.11 0.09

Contra Costa Concord-
2975 Treat Blvd
1998 4 0 2 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 3 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 13 3 5 0.15 0.11
1999 6 2 3 0.16 0.12
2000 8 3 4 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 34 15 34 0.16 0.12
1999 22 1 22 0.14 0.12
2000 29 2 26 0.13 0.11
2001** 30 4 25 0.15 0.11

Fresno Fresno-
1st Street
1998 23 8 23 0.15 0.12
1999 20 2 24 0.14 0.12
2000 29 2 27 0.14 0.11
2001** 29 3 24 0.13 0.11

Fresno Parlier 1998 34 6 31 0.16 0.12
1999 31 4 28 0.16 0.11
2000 51 8 43 0.14 0.11
2001** 43 4 32 0.13 0.11

Kern Arvin-
Bear Mountain Blvd
1998 37 3 35 0.13 0.12
1999 42 1 35 0.13 0.11
2000 46 4 41 0.14 0.11
2001** 41 6 36 0.13 0.11

Kern Edison 1998 36 9 33 0.17 0.14
1999 28 0 23 0.12 0.10
2000 43 4 38 0.15 0.11
2001** 26 2 24 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 49 18 45 0.17 0.14
1999 57 8 57 0.16 0.12
2000 67 14 62 0.15 0.12
2001** 58 14 54 0.15 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 30 15 24 0.22 0.17
1999 15 1 1 0.14 0.09
2000 23 7 14 0.17 0.15
2001** 37 10 22 0.18 0.14

Riverside Riverside-
Rubidoux
1998 35 17 29 0.19 0.17
1999 25 2 16 0.14 0.11
2000 28 1 16 0.14 0.11
2001** 28 3 24 0.14 0.12

San Bernardino Crestline 1998 57 34 52 0.24 0.21
1999 68 24 60 0.17 0.14
2000 65 16 48 0.18 0.15
2001** 59 19 54 0.17 0.14

San Bernardino Rim High School¹ 1998 62 31 60 0.24 0.21
1999 69 22 72 0.17 0.15
2000 72 20 65 0.19 0.16
2001** 49 15 49 0.16 0.13

San Bernardino San Bernardino-
4th Street
1998 37 24 25 0.21 0.18
1999 32 9 20 0.16 0.13
2000 32 5 15 0.15 0.13
2001** 33 10 27 0.16 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 60 35 54 0.24 0.21
1999 72 30 65 0.17 0.14
2000 77 24 66 0.18 0.15
2001** 76 23 66 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 August 6, 2001
 
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