In the summer, local weather forecasts often
include information about dangerous ozone levels.
But scientists are learning more and more about
another type of pollution that can reach harmful
levels even in the winter months. And as the Great
Lakes Radio Consortium’s Sarah Hulett reports… we
might be hearing more about this type of pollution in
our daily weather reports:
In the summer, local weather forecasts often include information about dangerous ozone levels. But scientists are learning more and more about another type of pollution that can reach harmful levels even in the winter months. And as the Great Lakes Radio Consortium’s Sarah Hulett reports, we might be hearing more about this type of pollution in our daily weather reports:
Parts of the region recently reached “code red” for poor air quality. And
that had some people perplexed. Warnings about dangerous levels of ozone are
frequent on hot summer days, especially in urban areas. But this was the
middle of winter.
The warnings were for high levels of tiny particles that federal regulators
only recently began monitoring. They’re spewn from diesel engines,
factories, power plants, and fireplaces. Air monitors in Michigan,
Minnesota, Pennsylvania, and Indiana recently registered unhealthy levels of
these particles – some of them for a few days straight.
Jim Haywood says the problem was an unusual weather event for this time of
year. Haywood is a meteorologist with the Michigan Department of
Environmental Quality. He says a high pressure system moved very slowly over
the Great Lakes region for several days. When you get high pressure, the air
below sinks, generating a layer of warm air that acts like a lid.
“So that warm air that was sinking effectively stops at a few hundred feet
from the surface of the ground. It acts like a cap. It does not let any of
the pollutants that are released at the surface pop up through that cap.”
So all the pollutants that would have gotten picked up and diluted by the
wind instead just hung out for days – building up, and reflecting sunlight
to create haze.
Eventually, a cold front pushed the high pressure system out of the way, and
took the pollution with it. But what about those few days when the Environmental Protection Agency was warning about unhealthy levels of particulate pollution? For people with
heart or lung disease, agency health officials say short-term episodes can
lead to asthma attacks or even heart attacks. And they say healthy children
and adults can experience throat and lung irritation.
Susan Stone is an environmental health scientist with EPA. She says
particle pollution warnings could soon become a staple of the daily weather
report – much like the familiar summer ozone warnings.
“With ozone, we have the network in place to be able to deliver those
forcasts, people are used to hearing that on TV, and we are working to
provide that same level of coverage for particle pollution.”
Stone says EPA is rolling out a new program called Enviro-Flash
nationwide. It sends real-time air quality information to people’s email
accounts or pagers. EPA is offering the service through state
environmental agencies. And beginning in 2010, areas that register
unacceptable levels of particle pollution will be required to clean up their
For the Great Lakes Radio Consortium, I’m Sarah Hulett.