Ground-level ozone exceeded healthy levels Tuesday for a tenth day this month – making it the worst year for June smog since 2012, according to records kept by the Mid-America Regional Council. Another ozone alert appeared likely for Wednesday as well.
Ozone has been a problem in Kansas City all month, with a three-day spate of exceedances June 3-7, followed by another day on the 9th and then three more June 14-16, said Doug Norsby, senior environmental planner for MARC.
What prompts an ozone alert?
An exceedance is when ozone levels are higher than 0.07 parts per million in an eight-hour average. An ozone alert is issued when conditions are right for elevated smog levels to exceed that average. Often it comes with an “air quality action day” message asking people not to gas up or do other things that could raise the ozone level.
The last year it was this bad was 2012, when there were nine exceedances in June, “and we’re at that right now,” Norsby said Tuesday morning.
However, those smoggy days in June 2012 happened during the last few days of the month, he said, “certainly not the third through the seventh.”
This year’s conditions more conducive to higher ozone levels have been “abnormally active both in terms of the number of days, the consecutive days and how early in the season it is,” Norsby said. Strings of consecutive ozone days typically happen later in July.
How to stay safe during an ozone alert
So far, all but one ozone day have fallen into the orange category, meaning the Air Quality Index is between 101 and 150. Recommendations are to drive less, avoid refueling, postpone yard work with power equipment and limit prolonged outdoor activity. The orange level is considered unhealthy for sensitive groups, such as people with asthma or breathing problems.
One day, June 6, ranked the ozone in the red zone, which is considered unhealthy for all.
How wildfires in Canada are impacting air quality in KC
Although the Canadian wildfires got a lot of publicity when they made for smoky skies earlier this month, the current smog can’t be blamed on particulates from Canada, Norsby said. Instead, it is due to a combination of the usual summer activities and a weather pattern of high pressure and calm winds.
Ozone is formed when gases given off from burning things, and evaporating gasoline, acetone and similar substances combine in sunlight, he said.
This month’s weather pattern has been especially conducive to that sunlight, he said. Normally June brings a series of spring storms and unstable air with gusty winds. But this year, Kansas City has been under a strong high pressure area with very little wind to clear out the gases, he said.
The wildfires’ contribution is not about smoke and ash particles, but about the nitrogen oxide gases they created that have been creeping this way.
Climate change and rising ocean temperatures also play a role
There are indications that climate change and rising ocean temperatures are also having an effect, he said. This year, climatologists declared an El Nino pattern of ocean currents after three years of La Nina currents. The last time there were three consecutive years of La Nina was in the 1950s, he said.
The ocean currents affect the air currents and weather patterns, including those that make the northern latitudes of Canada warmer and drier, with higher likelihood of fires, he said.
The air quality SkyCast forecast appears daily on the MARC web page, along with health recommendations.
Climate Action KC urged residents to follow the advice. “It’s troubling to see that Kansas City is again experiencing high levels of ozone,” the group said in a statement.
Roxie Hammill is a freelance journalist who reports frequently for the Post and other Kansas City area publications. You can reach her at roxieham@gmail.com.
