1 Emission and Air Quality Trends Review California July 2013

2 Project Objective  To develop and present publicly available information on trends in emissions and ambient air quality in the U.S. since 1999 in easy to understand visual and tabular formats

3 Emission Trends  Study Team collected and processed U.S. EPA emission inventories for years within the study period of interest ( )  By pollutant and source category electric utility coal fuel combustion mobile sources industrial fuel combustion & industrial processes all other

4 Emissions Data Summary  Data Obtained from EPA National Emission Inventory (NEI) and Trends Websites EPA’s Trends reports and emission comparisons include interpolations of all categories between key years (1999, 2002, 2005, 2008, 2011) at county-pollutant level Represented Pollutants: VOC, NOx, SO 2, and PM 2.5  Project Improvement The Study Team augmented above data with year specific CEM emissions (2002 through 2011)

5 Emission Changes  The following slides also include the tonnage-based emissions change from 1999 to 2011 for each pollutant  Negative values indicate decrease in emissions, positive values indicate an increase

6 California Emission Trends (VOC) Annual Emissions (Tons) Source Category Electric Utility Coal Fuel Combustion Mobile Sources740,112608,531501,217475,530455,075434,621414,767388,499362,231378,723 Industrial Fuel Combustion & Processes543,555546,012462,952461,266458,358455,789453,111449,838446,924293,398 All Others3,3325,17545,73645,48545,84046,18546,50546,75046,99342,941 Total1,286,9991,159,7181,009,910982,283959,275936,596914,384885,088856,149715,066 Annual Emissions Change (Percent since 1999) Source Category Electric Utility Coal Fuel Combustion0%10%1870%970%820%665%510%360%205%2185% Mobile Sources0%-18%-32%-36%-39%-41%-44%-48%-51%-49% Industrial Fuel Combustion & Processes0% -15% -16% -17% -18%-46% All Others0%55%1273%1265%1276%1286%1296%1303%1310%1189% Total0%-10%-22%-24%-25%-27%-29%-31%-33%-44%

7 California Emission Trends (VOC)

8 California Emission Trends (NOx) Annual Emissions (Tons) Source Category Electric Utility Coal Fuel Combustion ,001 Mobile Sources1,066,364969,1771,104,9041,093,3921,049,2311,005,070965,557903,022840,486675,605 Industrial Fuel Combustion & Processes245,636247,300205,136199,553197,636195,806193,994192,032190,123115,512 All Others25,17230,07714,31315,16216,56417,86214,01113,35712,2636,891 Total1,337,6421,247,0561,324,7921,308,2981,263,5951,218,8741,173,6721,108,4931,042,926799,008 Annual Emissions Change (Percent since 1999) Source Category Electric Utility Coal Fuel Combustion0%7%-7%-59%-65%-71%-77%-83%-88%113% Mobile Sources0%-9%4%3%-2%-6%-9%-15%-21%-37% Industrial Fuel Combustion & Processes0%1%-16%-19%-20% -21%-22%-23%-53% All Others0%19%-43%-40%-34%-29%-44%-47%-51%-73% Total0%-7%-1%-2%-6%-9%-12%-17%-22%-40%

9 California Emission Trends (NOx)

10 California Emission Trends (SO 2 ) Annual Emissions (Tons) Source Category Electric Utility Coal Fuel Combustion Mobile Sources64,32614,52666,64746,44543,09539,74434,65431,45928,26310,588 Industrial Fuel Combustion & Processes50,75051,850115,630109,534108,080106,632105,172103,719102,26524,279 All Others9512,7161,2971,4531,5191,4791,4041,4071,2651,166 Total116,65869,766183,862157,499152,751147,904141,270136,614131,81336,699 Annual Emissions Change (Percent since 1999) Source Category Electric Utility Coal Fuel Combustion0%7%-54%-89%-91%-92%-94%-95%-97%5% Mobile Sources0%-77%4%-28%-33%-38%-46%-51%-56%-84% Industrial Fuel Combustion & Processes0%2%128%116%113%110%107%104%102%-52% All Others0%186%36%53%60%55%48% 33%23% Total0%-40%58%35%31%27%21%17%13%-69%

11 California Emission Trends (SO 2 )

12 California Emission Trends (PM 2.5 ) Annual Emissions (Tons) Source Category Electric Utility Coal Fuel Combustion Mobile Sources37,21832,47931,42545,35944,39343,42742,62540,84839,07035,566 Industrial Fuel Combustion & Processes151,011101,94782,24884,18683,65783,18882,70782,11581,58894,582 All Others116,947139,86550,05649,35249,36149,36349,38249,36749,35775,282 Total305,184274,300163,801178,914177,426175,991174,724172,337170,020205,454 Annual Emissions Change (Percent since 1999) Source Category Electric Utility Coal Fuel Combustion0%7%790%106%77%47%18%-12%-41%195% Mobile Sources0%-13%-16%22%19%17%15%10%5%-4% Industrial Fuel Combustion & Processes0%-32%-46%-44%-45% -46% -37% All Others0%20%-57%-58% -36% Total0%-10%-46%-41%-42% -43%-44% -33%

13 California Emission Trends (PM 2.5 )

14 Emission Trends Summary  All pollutants have decreased since 1999 in aggregate across California  Onroad emission step increase seen between 2004 and 2005 is the result of EPA’s method change and MOVES model integration for estimating onroad mobile source emissions

15 Air Quality Design Values  Ozone Annual 4 th highest daily maximum 8-hour average averaged over three consecutive years Current standard = ppm  PM 2.5 Annual Annual arithmetic mean of quarterly means averaged over three consecutive years Current standard = 12 ug/m 3  PM Hour Annual 98 th percentile of daily averages averaged over three consecutive years Current standard = 35 ug/m 3

16 State-Wide Design Value (DV) Trends  Trends in state-wide maximum DV and average DV Max DV: Maximum DVs over all valid trend monitoring sites in the state in each overlapping three year period Average DV: Average of DVs over all valid trend monitoring sites in the state in each overlapping three year period  Compute linear trend via least-squares regression

17 Data Handling Procedures  O 3 design value (DV) for each overlapping three- year period starting with and ending with DV calculated using annual 4 th highest daily max 8-hr averages and percent of valid observations, based on EPA data handling conventions Data associated with exceptional events that have received EPA concurrence are omitted Selection of trend sites require valid DV in 9 out of 11 three-year periods between 1999 and 2011 Identification of nonattainment areas is with respect to the hour standard only

18 Data Handling Procedures  Annual PM 2.5 DV and 24-hr PM 2.5 DV for each overlapping three-year period starting with and ending with DV calculations based on EPA data handling conventions Data extracted from monitors that have a non- regulatory monitoring type are omitted Selection of trend sites require valid DV in 9 out of 11 three-year periods between 1999 and 2011

19 Trend Calculation  Trends based on linear least squares fit to rolling three year design values (DVs)  Negative trend indicates improving air quality  DVs based on each 3-year period: , , …  Notes On plots, DVs are for three year period ending in year shown (i.e., DV plotted as 2011 value) Ozone trend values expressed as ppb/year (1,000 ppb = 1 ppm); DVs are plotted as ppm Scale in units of ppm Trend in units of ppb/year

20 Max/Ave O 3 DVs and Trend

21 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Alameda, CA Alameda, CAN/A Amador, CA Butte, CA Calaveras, CA Contra Costa, CA Contra Costa, CA El Dorado, CA El Dorado, CA Fresno, CA Fresno, CA Fresno, CA Fresno, CA Fresno, CA Imperial, CA

22 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Imperial, CA Imperial, CA Inyo, CA Kern, CA Kern, CA Kern, CAN/A Kern, CA Kern, CA Kern, CA Kern, CAN/A Kern, CA Lake, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA

23 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Los Angeles, CA Madera, CA Marin, CA Mariposa, CA Mariposa, CA Merced, CA Monterey, CA Monterey, CA Napa, CA Nevada, CA Nevada, CA

24 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Orange, CAN/A Orange, CAN/A Placer, CA Placer, CA Placer, CA Riverside, CA Riverside, CA Riverside, CA Riverside, CA Riverside, CA Riverside, CA Sacramento, CA Sacramento, CA Sacramento, CAN/A Sacramento, CA

25 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Sacramento, CA Sacramento, CA San Benito, CA San Benito, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA San Bernardino, CA

26 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] San Diego, CA San Diego, CA San Diego, CA San Diego, CA San Diego, CA San Diego, CA San Diego, CA San Diego, CA San Francisco, CA San Mateo, CAN/A Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA

27 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Barbara, CA Santa Clara, CA Santa Clara, CA Santa Clara, CA Santa Cruz, CAN/A Santa Cruz, CA Shasta, CA Shasta, CA Solano, CA Sonoma, CA

28 Ozone Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed Monitoring SitesCounty DV [ppm] Trend [ppm/yr] Stanislaus, CAN/A Stanislaus, CA Sutter, CAN/A Tehama, CA Tulare, CA Tulare, CA Tulare, CA Tuolumne, CAN/A Ventura, CA Ventura, CA Ventura, CA Ventura, CA Ventura, CAN/A Ventura, CA Yolo, CA

29 Max/Ave PM 2.5 Annual DVs and Trend

30 Max/Ave PM Hour DVs and Trend

31 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV Alameda AlamedaN/A Butte Calaveras Colusa Contra Costa Fresno Fresno Fresno ImperialN/A38N/A Imperial7.4N/A-0.26N/A

32 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV Inyo7.3N/A0.19N/A KernN/A Kern Kern KingsN/A Lake Los AngelesN/A36N/A Los Angeles Los Angeles Los AngelesN/A28N/A-2.61

33 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV Los Angeles Los AngelesN/A Los Angeles Mendocino MercedN/A39N/A Monterey Nevada OrangeN/A29N/A Orange Placer

34 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV Riverside Riverside Riverside SacramentoN/A35N/A Sacramento SacramentoN/A35N/A San Bernardino San BernardinoN/A San Bernardino San BernardinoN/A29N/A0.27

35 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV San Bernardino12.1N/A San Diego San Diego San Diego San Diego San Francisco San Joaquin San Luis Obispo San Luis Obispo San MateoN/A -2.17

36 PM 2.5 Trends by Site in California Note: Only monitoring sites meeting data completeness criteria listed DV [ug/m 3 ] Trend [ug/m 3 per year] Monitoring SiteCountyAnnual24-HrAnnual DV24-Hr DV Shasta Solano Sonoma StanislausN/A Sutter Tulare Ventura Ventura Ventura Yolo

37 Air Quality Trends Summary  Average O 3 and PM 2.5 design values have decreased since 1999 in California  O 3 and PM 2.5 design values have decreased since 1999 in all currently designated O 3 and PM 2.5 non-attainment areas in California in which monitoring data met the 1999–2011 trends completeness criteria. Additional O 3 or PM 2.5 nonattainment areas in California in which monitoring data did not meet the 1999–2011 trends completeness criteria include: San Luis Obispo County (Eastern part), CA (ozone)