Clean Air Markets
2013 Program Progress – Clean Air Interstate Rule, Acid Rain Program, and Former NOₓ Budget Trading Program
This site summarizes annual progress under the Acid Rain Program (ARP), the NOₓ Budget Trading Program (NBP), and the Clean Air Interstate Rule (CAIR). Program data from the Cross-State Air Pollution Rule (CSAPR), which went into effect in 2015, is not currently covered in this report, as the report presents data from years prior to CSAPR implementation.
A cornerstone of effective emission reduction programs is transparency and data availability. This site features data on emissions, compliance, and environmental effects that EPA systematically collects and presents in accessible and interactive formats. The success of these programs is highlighted through substantial reductions in power sector emissions of SO₂ and NOₓ and improvements in air quality and the environment. Additionally, this site provides background through Historical Reports.
2013 ARP and CAIR at a Glance
- CAIR and ARP Annual SO₂ Emissions: 3.2 million tons
(69 percent below 2005)
- CAIR and ARP Annual NOₓ Emissions: 1.7 million tons
(53 percent below 2005)
- CAIR Ozone Season NOₓ Emissions: 470,000 tons
(41 percent below 2005)
- Ambient particulate sulfate concentrations have decreased since the ARP was implemented, with average concentrations decreasing by 60 to 65 percent in observed regions from 1989–1991 to 2011–2013
- The Northeast and Mid-Atlantic have showed the greatest improvement with an overall 64 percent reduction in wet sulfate deposition from 1989–1991 to 2011–2013