Canadian wildfire smoke has returned to the northeast, triggering New York and New Jersey to issue an air quality advisory for parts of the region.
As of midday Wednesday, the haze is worse in western portions of New Jersey and in western and central New York. Health officials have warned individuals in sensitive groups to avoid the outdoors as research shows wildfire smoke has a significant impact not just on the respiratory system, but on cardiovascular health as well.
The Environmental Protection Agency’s AirNow.gov site tracks air quality across the country and you can check out the map below:
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What do Air Quality Index numbers mean?
Simply put, the numbers show how clean or polluted the air is, or how many pollutants are present, according to the New York State Department of Environmental Conservation. While the numbers don't directly represent the number of pollutants in the air (for example, an AQI of 300 doesn't mean there are 300 pollutants in the air), the number is more of a yardstick to show pollution levels.
An overview published last year in the American Heart Association journal Circulation described wildfire smoke as "a rapidly growing threat to global cardiovascular health" and said that even short-term exposure can lead to heart attacks, strokes or cardiovascular-related deaths.
Much of the wildfire smoke is carried in the wind flow aloft, several thousand feet up. However, as temperatures climb during the day, the atmosphere becomes unstable. Pockets of warm, buoyant surface air begin to lift through the atmosphere – much like a hot air balloon rises. To fill the void, colder air aloft mixes down to the surface and takes its place, making the smoke worse in the afternoon.
A vertical circulation develops which is a very common phenomenon, but when there’s smoke lingering above, it gets mixed down to ground level, too.
To end the smoky haze over the tri-state area, one of two things needs to happen. Either the fires get put out, or the wind patterns shift and blow the smoke away from us.
Tri-State wildfire smoke forecast
