Air Quality Monitoring Data
Anchorage Carbon Monoxide (CO)
The Anchorage Garden site is located in the Anchorage CO maintenance area. The charts below show historical data from this monitor. The CO season is in winter, although in 2020, DEC started year-round monitoring. The Alaska Air Monitoring Plan contains more information about this monitor.
Note: The vertical axis of these charts extends to 10 ppm.
The following graphs show the maximum daily 8-hour average CO concentrations measured at the Anchorage Garden site 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
2019
2018
2017
2016
2015
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
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 |