Smoke produced by hundreds of wildfires burning across Canada has drifted thousands of miles and nearly circled the entire globe, with hazy skies now seen across parts of North America, Europe and even parts of Russia.

As Canada grapples with one of its worst wildfire seasons on record, smoke from the blazes have prompted air quality alerts across the U.S.

Most of the air quality alerts pertain to "sensitive groups," including people with heart or lung disease and asthma. However, air quality in parts of northern Minnesota, Wisconsin and the Upper Peninsula of Michigan is expected to be "unhealthy" for all individuals.