Michigan has been experiencing a PM-2.5 air
pollution episode in the last 24 hours.
The combined effect of usual and ordinary
emissions, some possible photo-chemical activity,
July 4th celebrations and long-range transport
of smoke from Canadian wildfires has caused some
high 1 hr average PM-2.5 concentrations, as well as
24 hour average PM-2.5 concentrations exceeding the
the level of the National Ambient Air Quality Standard (NAAQS) for
PM-2.5 of 35 micrograms/cubic meter (24-hour average).
Michigan Department of Environmental Quality data shows
24 hour concentrations of PM-2.5 detected from yesterday to
today that are over the
level of the PM 2.5 NAAQS at Allen Park, Dearborn,
Flint, Grand Rapids, Kalamazoo, Tecumseh and Ypsilanti.
Grand Rapids had the highest single 1 hour PM-2.5 at
330 micrograms per cubic meter [there isn't any 1 hr NAAQS for PM-2.5].
Grand Rapids has had the highest 24 hour average so far of 76.6
micrograms per cubic meter at 5 PM, followed by Allen Park at 58.1
micrograms per cubic meter at 5 PM. Actual 1 hour numbers at
these sites have been on the wane since about midnight.
http://www.deqmiair.org/...
[See PM-2.5 monitoring data at site.]
Grand Rapids 1 hr data available here:
http://www.deqmiair.org/...
NASA MODIS platform imagery from today shows remnants of
transported smoke plumes from Canada showing over
the state:
http://lance-modis.eosdis.nasa.gov/...
Note also that MDEQ's PM-2.5 air monitoring network geographical
coverage is limited, with many areas of the state that are not monitored
for ambient concentrations of PM-2.5.
Some high PM-2.5 has also been occurring in Illinois and Indiana as well.