Ash Cloud From 109-Year-Old Volcanic Eruption on Its Way Toward Alaskan Island

An ash cloud from a 109-year-old volcanic eruption is on its way toward Alaska's Kodiak Island.

The ash is from the 1912 eruption of Novarupta, a volcano located in Katmai National Park and Preserve on the Alaskan Peninsula that dropped volcanic ash still visible today.

Strong northwesterly winds near the park and preserve and Valley of Ten Thousand Smokes caused the volcanic ash to stir on Wednesday, The Associated Press reported.

"Generally, this time of year, we get these some of these northwestern winds that can come down from the Katmai region and really scour some of the free ash that's deposited from the 1912 eruption and then bring it up to height," Hans Schwaiger, a U.S. Geological Survey research geophysicist at the Alaska Volcano Observatory, told The Associated Press.

Winds were expected to carry the ash around 100 miles, southeast toward Kodiak Island. An aviation alert was issued to aircrafts. The cloud would not go above 7,000 feet, scientists estimated.

A light dusting of ash can fall on nearby communities because of some of these events.

"This particular one looks like it's not as ash rich as some of the other ones so there's probably going to be negligible ash fallout from it," Schwaiger said.

The Novarupta eruption is unique because it produced a lot of pyroclastic flows that came to rest on land, specifically the Valley of Ten Thousand Smokes, according to the National Park Service. It is now one of the most studied eruptions in the world.

For more reporting from the Associated Press, see below.

The three-day Novarupta eruption, one of the world's largest, began June 6, 1912, and sent ash as high as 100,000 feet (30,480 meters) above the Katmai region, located about 250 miles (402 kilometers) southwest of Anchorage. The U.S. Geological Survey estimates 3.6 cubic miles (15 cubic kilometers) of magma erupted, about 30 times what spewed from Mount St. Helens in Washington state 40 years ago.

The Novarupta eruption was the most powerful of the 20th century and ranks among the largest in recorded history.

The ash was deposited in what is now known as the Valley of Ten Thousand Smokes, depositing about 600 feet (183 meters) of ash in places.

High winds and dry, snow-free conditions will produce these ash clouds intermittently, the observatory said in a statement, adding that there is no eruption in place.

The statement said all seven of the volcanos in the Katmai area, including Novarupta, remain at the lowest level of green, or normal.