Why is Illinois’ air quality so bad today? Here’s what’s going on – NBC Chicago

Why is air quality in Chicago and parts of Illinois expected to be so bad on Monday that the Environmental Protection Agency issued an alert?

According to the National Weather Service, an air quality warning is in effect for parts of the Chicago area until midnight Tuesday after the EPA in Illinois declared an “air pollution action day” for some counties due to “elevated ground-level ozone levels.”

But what caused the change in air quality and where will it be worst?

What you should know:

Where was an air quality warning issued?

The day of action includes Cook, DuPage, Kane, Kendall, Grundy, Lake, McHenry and Will counties, the IEPA said, and will remain in effect until midnight.

What is an action day against air pollution?

According to the NWS, “an Air Pollution Action Day is declared when weather conditions are such that ozone and/or particulate matter levels meet or exceed the Air Quality Index Unhealthy Category for Sensitive Populations for a number of days on a widespread basis.”

In Illinois, an Air Pollution Action Day is declared when air quality is forecast to reach or exceed the Orange or Unhealthy/Sensitive Groups category for two or more consecutive days.

In Monday’s warning, authorities urged “vulnerable children and adults, especially those with lung or respiratory diseases such as asthma,” to limit their outdoor activities.

Why is the air quality so bad?

There are two main factors that can affect the air quality in an area: ground-level ozone and fine particulate matter, also known as PM2.5.

Monday’s World Quality Index found that ozone levels were expected to be the biggest problem for the region on Monday, although PM2.5 was the worst pollutant reported at 9:30 a.m.

However, this is not unexpected.

“Even if the weather forecast is orange (unhealthy for sensitive groups), there may be times during the day when air quality is OK for outdoor activities,” notes AirNow.gov. “Ozone levels are often lower in the morning.”

According to the U.S. Environmental Protection Agency (EPA), fine particulate matter, also called particle pollution, is a “mixture of solid particles and liquid droplets in the air.”

“Some particles, such as dust, dirt, soot or smoke, are large or dark enough to be seen with the naked eye. Others are so small that they can only be seen with an electron microscope,” the EPA explains.

PM2.5 and ground-level ozone are among the five major air pollutants regulated by the Clean Air Act, which also includes carbon monoxide, sulfur dioxide and nitrogen dioxide.

Even though there appears to be no connection, weather can have a significant impact on ozone and particulate matter pollution.

With dangerously hot temperatures and sunny weather in the Chicago area, it’s likely that the weather will impact air quality on Monday.

The reason for this, according to the NWS, is that “sunshine can trigger chemical reactions in some pollutants that lead to the formation of smog” and “higher air temperatures can accelerate chemical reactions in the air.”

The EPA stated that “ground-level ozone is formed as a result of chemical reactions between nitrogen oxides and
volatile organic compounds,” which means that “emissions from vehicles, power plants and industrial sources react chemically with sunlight.”

How bad is the air quality?

According to AirNow, the Chicago-area air quality index was at “Moderate” as of 6 a.m. Monday, which is level two on a six-level scale. Later in the day, the AQI is expected to reach level three, “Unhealthy for Sensitive Groups.”

The AQI is measured by five major air pollutants, including ground-level ozone, particle pollution and others. Ozone levels tend to be elevated during hot spells, and when residents use air conditioning in their homes and businesses, higher levels of particle pollution are created, according to officials.

People with lung diseases and other risk factors such as asthma, children and adolescents, older adults and people who regularly spend six or more hours outdoors a day should reduce their time outdoors during the alert level, according to the authorities.

Anyone who fears they may be affected should look out for the following symptoms: wheezing, coughing, rapid
Heart palpitations, fatigue, chest pain, and shortness of breath. If symptoms worsen, call your doctor or 911.

According to the EPA, people are encouraged to take the following steps, especially on action days, to reduce their contribution to air pollution.

• Limit driving – combine errands, walking or biking when possible.
• Avoid idling while driving, running errands, and keeping your vehicle and other engines
  correctly coordinated.
• Save energy to reduce energy consumption.
• Use environmentally friendly household and cleaning products.
• Avoid using gasoline-powered equipment such as lawn mowers and leaf blowers.
• Notify colleagues, friends and family to help protect their health and encourage them to take appropriate action.

How to check the air quality in your area

Click here to check the current air quality in your area.

At what level does air quality become unhealthy?

AirNow stated that its Air Quality Index determines the level of air pollution and related health concerns.

“When the AQI value is above 100, the air quality is unhealthy: first for certain sensitive groups of people, then for everyone if the AQI values ​​continue to rise,” the website says.

As soon as the values ​​are above 300, the highest level, which is described as “dangerous”, is reached.

There are six categories in total: green or good; yellow or average; orange or unhealthy for sensitive groups; red or unhealthy; purple or very unhealthy and maroon or dangerous.

Weather in Chicago today: Temperatures will feel like 100 degrees

In addition to the air quality warning, Monday is expected to be a muggy and hot day, continuing a long streak of temperatures above 90 degrees and even higher heat indices, NBC 5’s storm team said.

MORE: Chicago’s public pools will open for the season on Monday – with one big change

“Every single day this week will bring temperatures in the 80s and high humidity,” said NBC 5 meteorologist Alicia Roman.

Highs of 95 degrees Fahrenheit (35.4 degrees Celsius) are forecast for the Chicago area on Monday, which could break the Chicago area record set in 1957, Roman said.

“No cooling off on the lakeshore today,” Roman stressed.

In addition, humidity on Monday will range between “humid” and “extreme,” Roman added, pointing to dew point temperatures between 15 and 21 degrees Celsius.

“Hydrate, hydrate, hydrate,” Roman warned.

MORE: How to protect yourself from heat-related illnesses when temperatures rise

There could also be isolated thunderstorms during the day on Monday, Roman said.

“With the heat of the day, there is a small chance of a storm,” Roman said. “Not everyone will see it.”

In places where storms occur, there could be short, heavy rains, Roman said.

Temperatures around 30 degrees and the likelihood of isolated storms will persist for the rest of the week, Roman said. Relief will only come at the weekend when a cold front passes through.

More showers and thunderstorms are expected at this time, Roman said, and temperatures will drop back to around 30 degrees on Sunday.