Local grades from the State of the Air report

8/2/2019 Local grades from the State of the Air report

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Southern California Region

Counties: Los Angeles, Orange, Riverside, San Bernardino

SummarySouthern California is home to approximately half of all Californians. Coupled with the largepopulation, significant challenges due to weather and geography make improving airquality more difficult in the region. Sunny weather and other conditions in the basin allowsmog to form more easily. Surrounded by mountains on three sides, pollutants are alsoeasily trapped as stagnant air lingers in the basin. The worst air quality in the region tendsto occur in San Bernardino and the eastern parts of the basin due to smog transportpatterns from coastal areas. The South Coast Air Basin also transports pollution to the

Coachella Valley, Mojave Desert and San Diego areas.

2012 SOTA Grades (2008-2010 Air Quality Data)Ozone Pollution

Despite its lowest ever number of high ozone pollution days, the Los Angeles-LongBeach-Riverside metropolitan area is rated as the most ozone polluted area of theUnited States. The region has been ranked first for 12 out of 13 SOTA reports going backto SOTA 2000.

Individual counties in the region also dominate the national rankings of most polluted byozone: San Bernardino (1), Riverside (2), Los Angeles and (5). Orange County also earnedan F, but had 75 fewer annual bad ozone days recorded than other parts of the region.

Particulate PollutionShort Term-Particulates

The Los Angeles-Long Beach-Riverside area again ranked in the top five nationally forshort-term PM (4 th ). Each individual county earned an F grade and Riverside (4 th ), LosAngeles (8 th ) and San Bernardino (25 th ) are ranked among the most polluted counties inthe nation for short-term particulate pollution days. While there were small upticks inPM days in some parts of the region, San Bernardino County saw its annual averagenumber of PM days drop from 17.7 to 6.3 since last years report.

Annual Particulates The Los Angeles metro area is ranked 2 nd in the nation for annual particulate

concentrations, due to levels recorded in Riverside County. All other counties haveearned a PASS grade in SOTA 2012, including Los Angeles and San Bernardino whichpreviously failed.


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Grades

CountyOzoneDays

OzoneGrade

PMDays

PMGrade

AnnualPM

Value

AnnualPM

GradeLos Angeles 86.2 F 20.3 F 14.4 PassOrange 10.7 F 6.2 F 11.9 PassRiverside 111.3 F 28.8 F 17.0 FailSan Bernardino 127.8 F 6.3 F 14.5 Pass

Number of Days reported equals the weighted annual average of unhealthy days recorded over the

three-year period of 2008-2010.

Key Pollution Sources Mobile sources, including on- and off-road diesel fueled-vehicles, cars, trucks buses and

locomotives, ships and aircraft contribute approximately 90 percent of pollution in theregion

Ports and goods movement (contributes to regional pollution and generates significanttoxic diesel particulate matter hot spots near the Ports of Los Angeles and Long Beach)

Stationary sources including oil refineries and power plants

Area sources, including residential wood burning


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Clean Air ProgressOngoing, steady progress in reducing air pollution in Southern California is paying off, withgreat successes in reducing ozone and particularly PM pollution.

Ozone Pollution The areas average nu mber of high ozone days dropped by 33 percent, from 189.5 days

per year in the initial 2000 SOTA report (1996-1998 data) to 126.2 days in this yearsreport (2008-2010), a reduction of more than two months worth of unhealthy days peryear.

Particulate PollutionShort Term Particulates

Southern California has made significant progress in reducing the numbers of unhealthyparticulate pollution days. Since SOTA 2007 (2003-2005 data), the Los Angeles metro

area has seen a 53 percent reduction in short-term PM.

Annual Particulates Annual concentrations of particulates have dropped by over 40 percent throughout the

region, with all but Riverside County in attainment of federal standards for annual PMpollution and each earning a PASS grade in SOTA 2012 . Both Los Angeles and SanBernardino County improve d from a FAIL to a PASS since the last SOTA report.

It is important to note that pollution levels measured in this report were affected byfluctuations in weather conditions and the addition of new particulate monitoring stations.


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Trend Charts Unhealthy air days shown in charts below represent a 3-year weighted average number

of days recorded from 2008-2010. Days above the red line (3.3 annual average) earnthe location an F grade.

Documents

Local grades from the State of the Air report