Residents near Alaska's Mount Redoubt volcano are preparing for an eruption as two new holes spewing smoke appeared in the snow on the volcano, created by hot gases.

An analysis of the gases confirmed the presence of carbon dioxide, hydrogen sulfide, and sulfur dioxide, which indicates that a magma chamber is climbing upward, a geologist with the Alaska Volcano Observatory said.

Geologists conducted tests on materials collected during a survey flight over the volcano. The volcano is ranked as the ninth most dangerous in the U.S.

The National Geographis is reporting that one of the two new holes, melted through the snow and ice on Mount Redoubt, is the size of a football field.

Alaska residents remember the last time the volcano blew, which was in 1989. That eruption covered nearby areas with a layer of ash, which is ground rock and stays in people's lungs once they inhale the ash.

Residents are stocking up on paper masks to wear, along with fresh air filters for their vehicle air intake valves.