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Sunday was first day ozone reached unhealhy level locally in three years

DEP says ozone could reach unhealthy level on Monday

By Stephen Betts | Jun 06, 2021
Photo by: Stephen Betts The ozone reporting station at the Marshall Point Lighthouse in Port Clyde.

Port Clyde — Ground-level ozone locally reached an unhealthy level Sunday afternoon, the first time in more than three years.

The Maine Department of Environmental Protection has issued warning for Monday as levels are expected to rise.

"Ground-level ozone concentrations will be climbing in Maine on Monday June 7 and are expected to reach unhealthy levels," the DEP stated in a Sunday afternoon, June 6 announcement.

"Ozone levels have been high upwind since June 2.  High levels began around Lake Michigan and have been slowly migrating eastward.  By Saturday June 5 southern New England had very high levels of ozone even reaching into the unhealthy category.  Transport winds are expected to direct the higher values to Maine on Monday.  The unhealthy levels of ozone are possible along the entire coastline," the DEP stated

Ozone is created when emissions from smokestacks and motor vehicles interact with sunlight. Much of the pollution is generated south and west of Maine and blown into the state on warm summer days.

Ozone can pose health problems for the elderly and people with heart or respiratory problems, At high levels, healthy people can feel shortness of breath.

Ozone is considered at an unhealthy level when it reaches 70 parts per billion or greater for an eight hour period.

The Maine Department of Environmental Protection has ozone monitors at locations across the state. The nearest one for the Midcoast is at the Marshall Point Lighthouse in Port Clyde.

On Sunday, June 6, ozone exceeded 70 for eight hours -- 4 p.m. to 11 p..m -- with the peak being 81.9 reached at 7 p.m. at the Port Clyde station.

The last time that ozone reached an unhealthy level at the Port Clyde station was May 2, 2018 when the eight-hour average was 74.

The worst summer for ozone was in 2005 when statewide there were 21 days when at least one station reached unhealthy levels. That year, there were five days when unhealthy levels were reached at Port Clyde.

On unhealthy days, the elderly, infants, and people with respiratory and heart problems are urged to remain inside while healthy people are urged to avoid outdoor exercise.

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Comments (1)
Posted by: Kimberley Heilig | Jun 07, 2021 07:09

Perhaps this is why my senior pups were having a hard time yesterday.

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