Air Quality Monitoring Data
Anchorage Particulate Matter 2.5 (PM2.5)
The interactive charts below show historical data from PM2.5 monitoring at Anchorage monitoring sites. The Alaska Air Monitoring Plan contains more information about these sites and Realtime Air Quality Data is available for the public.
Note: The vertical axes of these charts extend from -10 µg/m3 to 100 µg/m3. Negative PM2.5 concentrations are included based on EPA reporting guidelines and are within the noise levels of the instrument when the ambient PM2.5 concentration is near zero. The PM2.5 concentrations represent the concentration at local conditions and have not been corrected for local temperature and pressure.
The following graphs show the 24-hour averaged PM2.5 concentrations measured at Anchorage Air Quality Monitoring Sites from 2023 through 2000.
- 2020
- 2019
- 2018
- 2017
- 2016
- 2015
- 2014
- 2013
- 2012
- 2011
- 2010
- 2009
- 2008
- 2007
- 2006
- 2005
- 2004
- 2003
- 2002
- 2001
- 2000
2020
The 2020 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. The 98th percentile concentration was 22.2 µg/m3
2019
The 2019 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3 except for nine days due to summertime wildfire smoke pollution. DEC will not file for an Exceptional Event with EPA until the dates become regulatory significant. The 98th percentile concentration was 42.2 µg/m3
2018
The 2018 PM2.5 24-hour concentrations were all below the 24-hour NAAQS of 35 µg/m3. No data were flagged as exceptional events this year. The 98th percentile concentration was 17.7 µg/m3
2017
The 2017 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3 with the exception of one day in January. No data were flagged as exceptional events this year. The 98th percentile concentration was 26.9 µg/m3
2016
The 2016 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as exceptional events this year. The 98th percentile concentration was 16.1 µg/m3
2015
The 2015 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as exceptional events this year. The 98th percentile concentration was 18.4 µg/m3
2014
The 2014 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3 with the exception of one day. The exceedance measured in May was caused by wildfire smoke. The 98th percentile concentration was 19.2 µg/m3.
2013
The 2013 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 15.7 µg/m3.
2012
The 2012 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentrations were 28.4 µg/m3 at the Garden site and 16.7 µg/m3 at the DHHS site.
2011
The 2011 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentrations were 17.3 µg/m3 at the Garden site and 11.6 µg/m3 at the DHHS site.
2010
The 2010 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentrations were 23.9 µg/m3 at the Garden site and 17.2 µg/m3 at the DHHS site.
2009
NOTE: In January 2009, the primary PM2.5 sampler changed from a filter based sampler operating on a 1-in-3 day schedule to a continuous monitor, leading to an increase in the quantity of data.
The 2009 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentrations were 24.6 µg/m3 at the Garden site and 15.3 µg/m3 at the DHHS site.
2008
The 2008 PM2.5 24-hour concentrations were below the 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 17.3 µg/m3.
2007
The 2007 PM2.5 24-hour concentrations were below the 2006 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 14.5 µg/m3.
2006
NOTE: In 2006 EPA strengthened the National Ambient Air Quality Standard by lowering the concentration to 35 µg/m3.
The 2006 PM2.5 24-hour concentrations measured were below the new 24-hour NAAQS of 35 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 26.9 µg/m3.
2005
The 2005 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 17.9 µg/m3.
2004
The 2004 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 31.9 µg/m3.
2003
The 2003 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 16.0 µg/m3.
2002
The 2002 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 15.8 µg/m3 at the Garden site and 18.2 µg/m3 at the Tudor site.
2001
The 2001 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 20.0 µg/m3 at the Garden site and 16.3 µg/m3 at the Tudor site.
2000
The 2000 PM2.5 24-hour concentrations were below the 1997 24-hour NAAQS of 65 µg/m3. No data were flagged as Exceptional Events this year. The 98th percentile concentration was 12.2 µg/m3 at the Garden site and 20.2 µg/m3 at the Tudor site.
Glossary
- NAAQS
- National Ambient Air Quality Standard - A health-based air quality standard set by EPA based on a review of available scientific information. NAAQS exist for criteria pollutants including Particulate Matter (PM2.5 and PM10), Carbon Monoxide (CO), Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), Ozone(O3), and Lead(Pb).
- EPA's NAAQS Webpage
- Concentration, µg/m3
- The amount of PM2.5 suspended in the air with units of micrograms(one-millionth of a gram) per cubic meter
- Exceedance
- A day when the 24-hour measured concentration of PM2.5 exceeds the NAAQS.
- 98th Percentile
- The daily value out of a year of PM2.5 monitoring data below which 98 percent of all daily values fall. 40 CFR 50 Appendix N - see section 4.5(a)
- 24-hour Design Value (DV)
- A three-year average of the 98th percentile value. An area is in violation of the NAAQS when the Design Values is greater than the 24-hour NAAQS for PM2.5, which is currently set at 35 µg/m340 CFR 50 Appendix N - see section 4.5(b)
- Clean Data Year
- A year when the 98th percentile value is less than the NAAQS.
- Exceptional Events
- Unusual or naturally occurring events that can affect air quality but are not reasonably controllable.
- EPA's Exceptional Events Webpage
- DEC's Exceptional Events Webpage
- Compliance with PM2.5 NAAQS
- 24-Hour: 98th percentile, averaged over 3 years, must be below the standardAnnual: Annual arithmetic mean, averaged over 3 years, must be below the standard. 40 CFR 50 Appendix N - see sections 4.1 and 4.2
| Standard | 1997 - 2006 | 2006 - 2012 | 2012 - 2024 | 2024 - current |
|---|---|---|---|---|
| 24-hour | 65 µg/m3 | 35 µg/m3 | 35 µg/m3 | 35 µg/m3 |
| Annual | 15 µg/m3 | 15 µg/m3 | 12 µg/m3 | 9 µg/m3 |