Pollutants, weather pattern combine to create air issues
When it came to air quality last week, western Wisconsin was seeing orange.
An air quality advisory for particle pollution (orange level) was issued for five consecutive days for much of Wisconsin by the Wisconsin Department of Natural Resources.
The advisory went into effect on Sunday and ran all the way through Thursday for many counties, including St. Croix, Pierce, Polk, Barron, Eau Claire and Pepin, even though the DNR's monitor in Somerset never ended up exceeding hazardous levels on those days.
The advisories are issued based on forecasts issued by state meteorologists.
While the extended poor air is unusual, according to Bart Sponseller, chief of air monitoring for the Wisconsin Department of Natural Resources, it doesn't mean that people should panic about the situation.
"You can factually say that the air quality in Wisconsin is getting better," Sponseller said. "But there are times, especially in the wintertime, when we get episodes of two or three days."
It's rare that much of Wisconsin suffers through poor air quality for four or five days in a row, he admitted, but the recent extended episode was due to weather patterns that held pollutants in the region for a long time.
Warm air sitting atop a cold snow pack creates an inversion, Sponseller said. When that happens, fine particle pollution hangs close to the ground and bothers people with lung issues. An advisory is issued by the DNR because elevated levels of fine particles in the air can be unhealthy for people in sensitive groups.
Fine particle pollution is composed of microscopic dust, soot, liquid droplets and smoke particles that are 2.5 microns or smaller. These fine particles come primarily from combustion sources, such as power plants, factories and other industrial sources, vehicle exhaust and wood burning.
Last week, thanks to a stalled high-pressure air mass in Wisconsin, the dirty air refused to move out. Things improved over the weekend and the air quality concerns eventually dissipated.
The last time such a bad air scenario played out was in the winter of 2005, Sponseller said.
"So it's not like it's an unheard of event," he noted.
It only seems like pollution issues are on the rise during winter months, Sponseller said, because the state has only been testing for particulate pollution for less than a decade, due to a lack of necessary measurement technology previously.
The DNR has been keeping track of ozone pollution for much longer and those episodes usually occur in the heat of the summer, Sponseller said, leading some to believe that the pollution issues were limited to those months.
"The fine particle pollution is highest in the winter," he said. "It's somewhat new in terms of measuring, so it's a surprise to people."
Still, an average winter in St. Croix County sees six state-issued advisories for particulate pollution (using data from 2005-09). There have been nine advisory days already this year.
While poor air quality can be a bother for healthy people, those with heart or lung disease and asthma, along with older adults and children, can feel the impact even more.
Health officials suggest that, when an air quality advisory is issued, people in those groups reschedule or cut back on strenuous activities during the alert period.
People with lung diseases such as asthma and bronchitis and heart disease should pay attention to cardiac symptoms like chest pain and shortness of breath or respiratory symptoms like coughing, wheezing and discomfort when taking a breath, and consult with their physician if they have concerns or are experiencing symptoms. Fine particle pollution deposits itself deep into the lungs and cannot easily be exhaled. People who are at risk are particularly vulnerable after several days of high particle pollution exposure.
While state officials downplayed the seriousness of the air quality episode, some environmental organizations were suggesting that it's time for the state to work toward even cleaner air.
"It is alarming that the frequency of these alerts is on the rise in Wisconsin," said Katie Nekola, energy program director for Clean Wisconsin. "Instead of restricting Wisconsin's most vulnerable citizens, we should be cleaning up our air by taking the biggest polluters - old, dirty coal plants - offline."
According to Nekola, Wisconsin's 41 coal units emit thousands of tons of soot, or fine particles, into the air every day.
"We can afford to shut down some of these old dirty coal plants," Nekola said. "Wisconsin has an oversupply of electric generation for the foreseeable future, yet we allow these coal plants keep on running, polluting our air and endangering our health."
Nekola said southeastern Wisconsin has been the hardest hit by air quality problems in the past, but every year it seems to spread further across the state.
For more information on pollution issues, call the Daily Air Quality Hotline at (866) 324-5924 (1-866-DAILY AIR).