ALASKA VOLCANO OBSERVATORY INFORMATION STATEMENT
U.S. Geological Survey
Thursday, October 26, 2023, 2:07 PM AKDT (Thursday, October 26, 2023, 22:07 UTC)
Strong winds blowing to the northwest in the region northwest of Aniakchak and east of Port Heiden have picked up loose volcanic ash and carried it to the northwest today. A cloud of resuspended volcanic ash is visible in satellite data and web camera views from Port Heiden. The National Weather Service has issued a SIGMET for this low-level event and suggests that the maximum cloud height is 3,000 ft (0.9 km) above sea level.
This phenomenon is not the result of volcanic activity and usually occurs seasonally in the spring and fall during times of high winds and dry, snow-free conditions in volcanic areas of Alaska. No eruption is in progress. Aniakchak remains at color code GREEN. Resuspended volcanic ash should be considered hazardous and could be damaging to aircraft and health.
For more information on volcanic ash and human health, visit the following website: http://volcanoes.usgs.gov/ash/
Official warnings about these ash resuspension events are issued by the National Weather Service: https://www.weather.gov/afc/
Forecasts of airborne ash hazard to aircraft: https://www.weather.gov/aawu/
Volcanic Ash Advisories: https://www.weather.gov/vaac/
Forecasts of ashfall: http://www.weather.gov/afc
Air quality hazards and guidance from Alaska Department of Environmental Conservation, Division of Air Quality: http://dec.alaska.gov/Applications/Air/airtoolsweb/Advisories/Index
Aniakchak volcano, located in the central portion of the Alaska Peninsula, consists of a stratovolcano edifice with a 6 mile (10 km) diameter summit caldera. The caldera-forming eruption occurred around 3,500 years ago. Post-caldera eruptions have produced lava domes, tuff cones, and larger spatter and scoria cone structures, including Half-Cone and Vent Mountain, all within the caldera. The most recent eruption occurred in 1931 and created a new vent and lava flows on the western caldera floor while spreading ash over much of southwestern Alaska. Aniakchak volcano is 16 miles (26 km) southeast of the nearest community, Port Heiden, and 416 miles (670 km) southwest of Anchorage, Alaska. It is located in Aniakchak National Monument and Preserve.
Chris Waythomas, Acting Scientist-in-Charge, USGS cwaythomas@usgs.gov (907) 786-7497
Jessica Larsen, Acting Coordinating Scientist, UAFGI jflarsen@alaska.edu (907) 378-5460
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.