the summit crater near the vent area of the 1989-90 eruption." March 15 Seismic activity at Redoubt increased beginning about 13:01 ATZ. An AVO observation flight reported that a steam and ash plume rose as high as above sea level and produced minor ash fall on the upper south flank of Redoubt. Later reports were that the plume was then mainly steam. On the basis of this change in activity, AVO increased the level of concern and alert level to ORANGE/WATCH. Emissions The material ejected from the volcano mainly consisted of water vapor, along with smaller amounts of carbon dioxide and sulfur dioxide. Further study by airborne monitors suggests that the materials were not oxidized much, and little of the concentration contained sulfates, less than 20%. Large scale eruptions begin Mount Redoubt erupted explosively late in the evening of March 22, 2009. AVO has recorded numerous volcanic eruptions and/or explosions at Redoubt volcano. See also List of mountain peaks of North America List of mountain peaks of the United States List of mountain peaks of Alaska List of Ultras of the United States List of volcanoes in the United States References External links and resources Alaska Volcano Observatory (to follow 2009 volcanic activity by geologists reports) Live updates from the AVO Twitter page Webcams: Redoubt Volcano Webcam, USGS (intermittently available). View of north flank of Redoubt from AVO's Redoubt Hut, approximately from Redoubt's summit crater. Redoubt-CI webcam, Chevron via Alaska Volcano Observatory. View of northeast face from Oil Platform Anna in Gompertz Channel of Cook Inlet at , approximately NE of mountain. Daily Time-lapse animation of the Mount Redoubt Hut Web Cam Mount Redoubt Seismic Webicorders (near-real time seismic record from station near peak) Satellite imagery of the 23, 24, and 26 March 2009 eruptions (CIMSS Satellite Blog) Time lapse video and photos of the March 27, 2009, eruption, taken from Ninilchik BBC page with footage and links to other pages on the volcano Large-format photo essay of the Mount Redoubt eruption from "The Big Picture" blog on Boston.com. Volcanoes of Kenai Peninsula Borough, Alaska Mountains of Kenai Peninsula Borough, Alaska Stratovolcanoes of the United States Active volcanoes Volcanoes of Alaska Mountains of Alaska Highest points of United States national parks Lake Clark National Park and Preserve Aleutian Range 20th-century volcanic events North American 3000 m summits National Natural Landmarks in Alaska VEI-3 volcanoes Pleistocene stratovolcanoes Holocene stratovolcanoes