A smog-like haze that hung over part of Alaska's Kodiak Island this week was courtesy of a volcanic eruption—100 years ago.
The National Weather Service says strong winds and a lack of snow Tuesday helped stir up ash from the 1912 eruption of Novarupta, the largest volcanic blast of the 20th century.
This week, ash from the volcano drifted to about 4,000 feet (1,219 meters) and across Kodiak Island, prompting an aviation alert. The news was first reported by KMXT radio.
Weather service meteorologist Brian Hagenbuch said the event isn't unheard of, but isn't very common, either.
When Novarupta erupted in June 1912, it spit ash as high as 100,000 feet (30,480 meters) above the sparsely populated Katmai region, covering the remote valley to depths up to 700 feet (213 meters).
The volcanic cloud spread across the U.S. and traveled as far as Algeria in northern Africa in what was one of the five largest volcanic eruptions in recorded history.
Dave Schneider, a geophysicist with the Alaska Volcano Observatory, said it's no surprise a lot of ash remains at Novarupta. He said it will be that way for "many, many more years."
Explore further: A 3-D view of the Greenland Ice Sheet opens window on ice history