UPDATE: The Aviation Color Code has been reduced to ORANGE and the Volcano Alert Level to WATCH for Pavlof Volcano. Although the eruption of Pavlof continues, seismic tremor has deceased over the past 12 hours and has remained relatively steady throughout the day at a much lower level than that of yesterday. There are no reports of ash falling in nearby communities.
Hazardous conditions still exist on some parts of the volcano due to continued pyroclastic and lahar activity. Ash in the vicinity of the volcano remains a hazard to local air traffic.
Conditions are likely to continue to change. Check back here for updated reports on Pavlof’s conditions.
One of Alaska’s most active volcanoes—Pavlof—is currently erupting. At the time of this post, its low-level eruption that began late on Friday, May 30, has escalated, and the volcano is now producing a relatively continuous steam and ash plume that has reached up to 24,000 feet above sea level. Recent satellite images show a plume extending over 80 km southeast of the volcano. The Aviation Color Code has been raised to RED and Volcano Alert Level has been raised to WARNING.
An Aviation Color Code of RED indicates that an eruption is imminent with significant emission of volcanic ash into the atmosphere likely or that an eruption is underway or suspected with significant emission of volcanic ash into the atmosphere.
Located in a remote and sparsely populated section of the Aleutian Range close to the southwestern end of the Alaska Peninsula, Pavlof is one of the most active volcanoes in the Aleutian arc, having erupted more than 40 times since the early 1800’s.
Pavlof’s most recent eruption took place between May and July of 2013. Typical eruptions of Pavlof are characterized by relatively low-energy lava fountaining and minor emissions of ash, steam, and gas. So far in 2014, volcanic ash has reached as high as 22,000 feet above sea level on the afternoon of June 2. The ash plume has interfered with regional airlines and trace amounts of ash fall may be expected on nearby communities depending on wind direction and strength. The ash plume is currently too low to impact commercial airliners that fly between North America and Asia at altitudes generally above 30,000 feet.
Elevated surface temperatures at the volcano summit have been observed in satellite images since May 30, indicating lava at the surface. On the night of June 2 , strong incandescence at the summit indicative of lava fountaining was observed in web camera images from a site located in Cold Bay, about 35 miles southwest of the volcano Local seismometers are detecting seismic tremor and occasional water and sediment flows (lahars) that are being produced by mixing of hot volcanic rock and snow and ice on the north flank of the volcano.
The U.S. Geological Survey (USGS) is responsible for monitoring and issuing timely warnings of potential volcano activity. The USGS and its partners operate five volcano observatories, and monitoring of this volcano is coordinated through the Alaska Volcano Observatory (AVO).
AVO is a joint program of the USGS, University of Alaska Fairbanks Geophysical Institute, and the State of Alaska Division of Geological and Geophysical Surveys.
Scientists at AVO were able to detect unrest at Pavlof volcano that confirmed eruptive activity was occurring. AVO immediately sent notifications out to emergency-management authorities and those potentially affected.
Volcanic eruptions can last weeks to months, and sometime years, so the exact timing is unknown for when Pavlof will rest. AVO will continue to monitor Pavlof and provide updates in the event of future activity. Past eruptions of Pavlof have lasted as little as two days and as long as 850 days (2 years, 3 months, 28 days)
Signs that the volcano was becoming restless were determined through a combination of monitoring data.
At Pavlof, a strong thermal signal was observed in satellite data at the summit that coincided with elevated seismic levels. As the activity intensified, regional infrasound arrays began to detect airwaves produced by the eruption. A low-level steam plume was visible in satellite imagery and in the FAA web camera located in Cold Bay. Pilots, mariners and other observers provide valuable information about volcanic activity at Pavlof and so far AVO has received a number of photographs and observations from people in the area.
AVO’s analysis of the eruption, including the amount of ash and the duration of the explosive phases, are key inputs into the forecasts by National Oceanic and Atmospheric Administration’s National Weather Service (NWS) of where the ash cloud will drift and what areas may be affected by ash fall. These forecasts by NWS are used by the aviation industry to avoid flying into the ash.
The USGS has developed a new ash cloud dispersal and fallout tool—a computer model known as Ash3d—that is being employed by AVO. This numerical model provides information about where, when, and the amount of ash fall that is expected to occur for a specified set of eruption source conditions. This information helps guide decisions on whether planes can safely land or depart, health warnings, potential impacts to infrastructure, and even when ash will stop falling and cleanup can begin.
Pavlof is monitored with on-the-ground seismic stations, satellite remote sensing, and web cameras operated by the Federal Aviation Administration (FAA). Also, a regional infrasound network operated by the University of Alaska-Fairbanks Geophysical Institute has helped detect explosions from Pavlof.
Visit the AVO website for updated alerts and activity reports on Pavlof volcano. Near real-time views of the volcano are available on the FAA webcam located in Cold Bay about 37 miles southwest of Pavlof.
Alaska’s volcanoes make up about 31% of all active volcanoes in the United States. There are 52 that have been active within the last 300 years and can be expected to erupt again. At present, 28 are monitored with ground-based instrumentation, and all are monitored daily using satellite remote sensing.
Although most of the volcanoes in Alaska are remote and not close to populated areas, millions of dollars of air freight and 20,000-30,000 people fly over active Alaskan volcanoes daily traveling between North America and Asia. In fact, the Ted Stevens Anchorage International Airport is ranked the fifth busiest air cargo hub in the world based on tonnage. In addition to the threat that volcanic ash poses for aviation safety, the economic impacts due to disruption of air traffic can be substantial. One study estimated costs of five billion dollars from the week-long closure of European airspace caused by the eruption of Iceland’s Eyjafjallajökull volcano in 2010.
USGS science is helping keep what are natural events from turning into major disasters.
The United States has approximately 169 active volcanoes, and more than half of them could erupt explosively. When the violent energy of a volcano is unleashed, the results can be catastrophic. Lava flows, debris avalanches, and explosive blasts have devastated communities. Noxious volcanic gas emissions have caused widespread lung problems. Airborne ash clouds from explosive eruptions have caused millions of dollars damage, including causing airplane engines to shut down in flight.
To keep communities safe, it is essential to monitor volcanoes so that the public knows when unrest begins and what hazards can be expected. USGS efforts have improved global understanding of how volcanoes work and how to live safely with volcanic eruptions.
The USGS Volcano Hazards Program operates a total of five volcano observatories in cooperation with universities and state agencies. They are the Cascades Volcano Observatory, Yellowstone Volcano Observatory, California Volcano Observatory, Hawaiian Volcano Observatory, and Alaska Volcano Observatory. USGS also monitors and reports on volcanoes in the northern Marianas Islands.
In April, 2013, AVO celebrated 25 years of monitoring and studying Alaska volcanoes.
Find out about the National Volcano Early Warning System (NVEWS), which is a proposed national-scale plan to ensure that volcanoes are monitored at appropriate levels given their associated threats.
Watch a video about USGS science on volcano hazards.
Images of Pavlof may be found here.