The two most active volcanoes in Alaska (in recent years) — Pavlof Volcano and Cleveland Volcano — are now both erupting. As of now, the activity is at relatively low levels, but the potential is there for larger eruptions, or a general intensification of activity.
Mount Pavlof (Pavlof volcano) is situated near the western end of the Alaska Peninsula. It’s one of the most regularly active volcanoes in all of the Aleutian arc, it’s experienced over 40 eruptions since modern observations began during the late 18th century.
“Pavlof has been erupting since May 13, 2013, with relatively low-energy lava fountaining and minor emissions of ash, steam, and gas. So far, volcanic ash from this eruption has reached as high as 22,000 feet above sea level. The ash plume has interfered with regional airlines and resulted in trace amounts of ash fall on nearby communities. 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.”
Mount Cleveland (Cleveland Volcano), calls Chuginadak Island in the Aleutian Islands its home. Like Pavlof, Cleveland is one of the most persistently active of Alaska’s volcanoes, in recent years anyways. It’s been showing signs of growing unrest since the early 1980’s. there have been at least 19 eruptive events there since then.
“The current episode of eruptive activity at Cleveland has been characterized by single, discrete explosions, minor ash emissions, and small flows of lava and debris on the upper flanks of the volcano. On several occasions, ash-producing explosions have occurred reaching as high as 35,000 feet. A small lava dome formed in the summit crater of Cleveland volcano in late January, 2013. At that time, the dome was about 300 feet in diameter and remained that size until a brief eruption on May 4 explosively removed a portion of the dome. The presence of a lava dome increases the possibility of an explosive eruption, but it does not necessarily indicate that one will occur.”
The USGS is currently monitoring both eruptions, looking out for signs that may indicate future intensification of activity. Volcanic eruptions can last a long time — anywhere from a couple of weeks to a couple of years.
Alaska is home to over 31% of all the active volcanoes in the US — 52 of which are known to have been erupted within the past 10,000 or so years, and will likely erupt again. As of right now, only 28 of these are being monitored with ground-based instrumentation, the rest are only monitored via 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 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.”
“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 engines to shut down in flight.”
As there haven’t been any major volcanic eruptions in the past hundred or so years, it’s easy to be complacent about volcanoes. But make no mistake, the destruction that they are capable of causing (and the secondary effects caused by them) can completely eclipse nearly any other type of natural disaster.