May 2nd is the start of Air Quality Awareness Week in 2016. Linn County Public Health (LCPH) is recognizing the positive downward trends in Air Pollution that has been monitored in Linn County. Throughout the week we also recognize the local voluntary programs that residents and guests may see in 2016 to sustain this trend.
Linn County is one of only two counties in Iowa that measure the air pollutants in the air we breathe. While the LCPH staff continuously analyzes the air for numerous pollutants, two that have our greatest attention are Ozone and Particulate Matter.
After several years of decline, Linn County Ozone values began rising again in 2010. However, after 2012, Linn County Ozone value again began declining where in 2015 they have reached a historic low.
Linn County particulate pollution peaked in 2010 before beginning a steady decline. For the last three years, particulate pollution has leveled off to a value that is about one-third below the EPA nation health standard.
Air Quality Data is available online at https://monitoring.linncleanair.org/. All data is updated hourly.
According to EPA 57.3 million people live in an area where air quality does not fully meet all EPA health standards, 43 million people live in an area that does not meet the ozone health standard and 32.2 million who live in an area that does not meet the particulate matter health standard. (U.S. EPA, 2016)
“There often is a misperception that because Linn County has larger population and more industrialized, our air pollution is worse than other Iowa counties,” says the Linn County Public Health Director. “However, when reviewing the ambient air monitoring data from across the state, that assumption turns out to be false.” The 2015 Iowa Department of Natural Resource, “Iowa Ambient Air Quality Annual Report: 2015” shows that Linn County has some of the lowest monitored ozone levels in Iowa and is in the middle when it comes to fine particulate matter. (Iowa Department of Natural Resources, 2015)
A variety of factors affect the concentration of air pollutants in the atmosphere including emissions from power, industrial, residential, transportation and residential sources. Some of these emissions are generated locally but most are generated elsewhere and transported into Linn County. EPA reports that emissions of fine particulate matter across the country have decreased 33% since 2000. Nitrogen Oxides (NOx) and Volatile Organic Compounds (VOCs) combine in the presence of sunlight to form Ozone. NOx emissions have reduced by 41% since 2000 and VOC emissions have reduced by 16% according to that same EPA report. (U.S. EPA, 2016) Weather, plays a role, too. Greater more intense hot days can generate higher levels of pollution and certain weather events can either sweep out or bottle up pollutants in a geographic area.
Iowa Department of Natural Resources. (2015). Iowa Ambient Air Quality Annual Report. Iowa Department of Natural Resources.
U.S. EPA. (2016, February 16). Air Quality Trends. Retrieved April 28, 2016, from United States Environmental Protection Ageny: https://www3.epa.gov/airtrends/aqtrends.html