Fast Five: EGLE's Air Quality forecasts provide important information to Michigan residents

Date:  May 04, 2020  
Time: All Day Event

Clean Air Action Forecasting photo slide

(During Air Quality Awareness Week in Michigan (May 4 to 8), EGLE meteorologists Jim Haywood and Stephanie Hengesbach look at the importance of EGLE's air quality forecasts in this Fast Five edition of MI Environment.)

How long has EGLE provided air quality forecasts?

EGLE started providing air quality forecasts back in 1994. At that time, the forecasting program was only for ozone and forecasts were done in the spring and summer months.

What do the forecasts track?

We are tasked with determining air quality levels across the state of Michigan. The two pollutants we forecast are fine particulate (PM2.5) which is forecast year-round, and ozone which is prevalent during the spring and summer months. If we feel either PM2.5 or ozone will reach or exceed the Unhealthy for Sensitive Groups (USG) range, we will issue a Clean Air Action Day. This Action Day notifies the public of the threat for increased pollution. In our Action Day message, we highlight steps individuals can take to protect their health, and steps they can take to help decrease pollution on those given days.

How can the forecasts help people?

The purpose of our air quality forecasts, including Clean Air Action Days, is to inform the public on current and expected air quality conditions. This knowledge is helpful, especially to those susceptible to higher levels of pollution including the elderly, immune-compromised and those with asthma or other respiratory conditions

We are moving into our busiest time of the year regarding air quality forecasting, the ozone season. The ozone forecast season typically runs from late spring through the summer months. Ozone in the upper atmosphere is a good thing, helping to protect us from the sun's rays. However, ozone in the air we breathe can be harmful for many people, especially those with asthma, children, older adults, and people who are active outdoors. Ozone at ground level develops when a chemical reaction occurs between heat from the sun's rays and pollution that exists near or just above the ground (precursors).

Issuing Clean Air Action Days is our way to notify the public on the threat for increased pollution so they can take steps to protect their health, and steps they can take to help decrease pollution levels where they live.

For individual health, that means limiting prolonged outdoor exertion on Action Days.

For reducing pollution levels, here are some tips:

  • High ozone days:
    • Refuel cars and trucks after dusk, when emissions are less likely to produce ozone
    • Delay using gasoline-powered lawn and garden equipment until air quality is healthy again
    • Delay using household, workshop, and garden chemicals until air quality is healthy again
  • High PM2.5 days:
    • Reduce the number of trips you take in your car
    • Reduce or eliminate fireplace and wood stove use
    • Avoid using gas-powered lawn and garden equipment
    • Avoid burning leaves, trash and other materials

Individuals can sign up to receive advanced notice about environmental issues via automated e-mail and text messages on the EnviroFlash website. It's a free service.

Have you noticed changes in the frequency of "moderate" or worse forecasts over the years? If so, to what do you attribute that?

Overall, the frequency in moderate air pollution levels has increased. However, the reason for this is not because the air is becoming "dirtier." In fact, the air we breathe has become cleaner over the years. The increase in frequency instead is attributed to the lowering of the thresholds for both ozone and fine particulate.

In past years when thresholds were higher, we issued several Action Day advisories, per year, for levels higher than moderate. Today, even with the lowered thresholds, we are issuing fewer Action Day advisories, per year, which is a testament to improving air quality.

Do you use your meteorology background in creating these forecasts?

Yes, we use our meteorology background when creating air quality forecasts. Pollutant levels are driven by weather conditions; therefore, when making our air quality forecasts, we start by evaluating weather forecast maps to determine the current and expected weather conditions. We take current air quality trends and then determine how the trends will change based on the weather forecast. With this information, we make our air quality forecast for the state.

More information on air quality levels and forecasts can be found on the EGLE MIair Air Quality Index website and EGLE's MI EnviroMINUTE Clean Air Action Days video.


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