This ozone season, MARC issued 45 yellow SkyCasts and four orange Ozone Alerts for the Kansas City region’s air quality maintenance area. The cool, wet spring and late arrival of summer weather provided a welcome relief from high ozone levels seen over the last two years and contributed to the significantly lower number of yellow and orange SkyCasts.
The SkyCast is issued daily during ozone season (April 1–Oct. 31) and corresponds with the Air Quality Index (AQI), a public information tool that associates colors and health messages with ranges of air pollutant concentrations. This season, only two days exceeded the eight-hour ozone concentration standard of 75 parts-per-billion (ppb) set by the U.S. Environmental Protection Agency to protect public health.
Over the last five years, with the exception of 2010, the maximum ozone values in the Kansas City region hovered just above the 75 ppb standard (see graph). The next required review of the ozone standard is set for 2013. When the EPA completes its review, the region’s air quality status will likely be reassessed based on data collected during the three most recent ozone seasons — 2011, 2012 and 2013.
Another factor in the reassessment is that the EPA is expected to lower the ozone concentration standard from 75 ppb to somewhere between 60 and 70 ppb. Because of this, we expect our region may soon be designated as “nonattainment,” triggering changes to future regulatory requirements. In anticipation of these changes, the region has updated its award-winning Clean Air Action Plan (CAAP) annually and has signed on to the EPA’s Ozone Advance program. These proactive steps will give the region some ability to leverage the CAAP’s voluntary strategies to reduce ozone-forming and greenhouse gas emissions in the Kansas City region and may reduce the need for imposed regulations.