Jan. 30: This image provided by the Alaska Volcano Observatory/U.S. Geological Survey shows the Redoubt Volcano near Anchorage, Alaska. Scientists with the Alaska Volcano Observatory on Friday flew close to Drift Glacier and saw vigorous steaming emitted from a football-size area on the north side of the mountain. By Saturday, they had confirmed the area was a fumarole, an opening in the earth that emits gases and steam, and that it had doubled overnight.

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