Table 7-7: Air Pollution in the 50 Largest Metropolitan Areas: 2009–2014
Monday, November 9, 2015
(Number of days with AQI value greater than 100)
| Metropolitan area | AQI days > 100 | |||||
|---|---|---|---|---|---|---|
| 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | |
| Atlanta-Sandy Springs-Marietta, GA | 18 | 29 | 46 | 19 | 3 | 10 |
| Austin-Round Rock, TX | 5 | 3 | 7 | 4 | 1 | 0 |
| Baltimore-Towson, MD | 15 | 36 | 25 | 20 | 5 | 4 |
| Birmingham-Hoover, AL | 5 | 15 | 23 | 10 | 1 | 3 |
| Boston-Cambridge-Quincy, MA-NH | 5 | 5 | 3 | 6 | 5 | 0 |
| Buffalo-Niagara Falls, NY | 2 | 3 | 2 | 8 | 1 | 0 |
| Charlotte-Concord-Gastonia, NC-SC | 4 | 15 | 18 | 11 | 0 | 0 |
| Chicago-Naperville-Joliet, IL-IN-WI | 34 | 38 | 27 | 47 | 12 | 16 |
| Cincinnati-Middletown, OH-KY-IN | 11 | 30 | 47 | 43 | 11 | 10 |
| Cleveland-Elyria-Mentor, OH | 63 | 74 | 75 | 59 | 13 | 15 |
| Columbus, OH | 1 | 8 | 11 | 14 | 2 | 1 |
| Dallas-Fort Worth-Arlington, TX | 34 | 18 | 40 | 36 | 33 | 14 |
| Denver-Aurora, CO | 8 | 17 | 21 | 26 | 23 | 11 |
| Detroit-Warren-Livonia, MI | 12 | 27 | 20 | 38 | 7 | 12 |
| Hartford-West Hartford-East Hartford, CT | 3 | 9 | 8 | 16 | 11 | 8 |
| Houston-Sugar Land-Baytown, TX | 31 | 35 | 38 | 34 | 19 | 7 |
| Indianapolis-Carmel, IN | 20 | 20 | 31 | 29 | 11 | 30 |
| Jacksonville, FL | 4 | 18 | 19 | 5 | 2 | 3 |
| Kansas City, MO-KS | 46 | 25 | 53 | 72 | 42 | 53 |
| Las Vegas-Paradise, NV | 8 | 11 | 25 | 29 | 16 | 7 |
| Los Angeles-Long Beach-Anaheim, CA | 112 | 85 | 105 | 106 | 80 | 90 |
| Louisville/Jefferson County, KY-IN | 35 | 55 | 36 | 45 | 18 | 31 |
| Memphis, TN-MS-AR | 4 | 14 | 22 | 20 | 2 | 2 |
| Miami-Fort Lauderdale-Pompano Beach, FL | 2 | 4 | 9 | 2 | 3 | 3 |
| Milwaukee-Waukesha-West Allis, WI | 7 | 9 | 5 | 26 | 0 | 3 |
| Minneapolis-St. Paul-Bloomington, MN-WI | 8 | 9 | 2 | 5 | 2 | 1 |
| Nashville-Davidson--Murfreesboro--Franklin, TN | 1 | 10 | 13 | 23 | 1 | 2 |
| New Orleans-Metairie-Kenner, LA | 95 | 68 | 89 | 44 | 25 | 11 |
| New York-Northern New Jersey-Long Island, NY-NJ-PA | 26 | 41 | 29 | 22 | 15 | 11 |
| Oklahoma City, OK | 5 | 3 | 27 | 23 | 3 | 0 |
| Orlando-Kissimmee, FL | 1 | 2 | 8 | 1 | 0 | 1 |
| Philadelphia-Camden-Wilmington, PA-NJ-DE-MD | 15 | 38 | 20 | 27 | 11 | 15 |
| Phoenix-Mesa-Scottsdale, AZ | 67 | 44 | 121 | 94 | 87 | 107 |
| Pittsburgh, PA | 69 | 82 | 54 | 59 | 18 | 18 |
| Portland-Vancouver-Beaverton, OR-WA | 15 | 2 | 17 | 2 | 16 | 1 |
| Providence-New Bedford-Fall River, RI-MA | 2 | 16 | 11 | 14 | 9 | 1 |
| Raleigh-Cary, NC | 0 | 3 | 7 | 5 | 0 | 0 |
| Richmond, VA | 1 | 11 | 12 | 12 | 1 | 1 |
| Riverside-San Bernardino-Ontario, CA | 145 | 139 | 151 | 153 | 130 | 140 |
| Sacramento--Roseville--Arden-Arcade, CA | 46 | 24 | 60 | 51 | 35 | 35 |
| Salt Lake City, UT | 30 | 21 | 22 | 11 | 45 | 17 |
| San Antonio-New Braunfels, TX | 3 | 4 | 12 | 8 | 10 | 3 |
| San Diego-Carlsbad-San Marcos, CA | 30 | 19 | 13 | 22 | 19 | 18 |
| San Francisco-Oakland-Hayward, CA | 14 | 10 | 8 | 5 | 7 | 7 |
| San Jose-Sunnyvale-Santa Clara, CA | 9 | 10 | 4 | 4 | 8 | 5 |
| Seattle-Tacoma-Bellevue, WA | 21 | 1 | 13 | 9 | 8 | 6 |
| St. Louis, MO-IL | 93 | 87 | 78 | 97 | 35 | 9 |
| Tampa-St. Petersburg-Clearwater, FL | 18 | 12 | 14 | 13 | 3 | 1 |
| Virginia Beach-Norfolk-Newport News, VA-NC | 0 | 8 | 11 | 4 | 0 | 0 |
| Washington-Arlington-Alexandria, DC-VA-MD-WV | 7 | 34 | 21 | 24 | 5 | 4 |
KEY: AQI = Air Quality Index
NOTES: Historical data are reviesd. Air Quality Index (AQI) is an indicator of overall air quality and takes into account all of the criteria air pollutants measured within a geographic area. Although AQI includes all available pollutant measurements, areas may have monitoring stations for some, but not all, pollutants. An AQI value greater than 100 is considered unhealthy. Metropolitan area rank is based on 2010 U.S. Census population.
SOURCE: U.S. Environmental Protection Agency, AirData, available at www.epa.gov/airquality/airdata as of July 2015.