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Mount Cleveland (also known as Cleveland Volcano) is a nearly symmetrical stratovolcano on the western end of Chuginadak Island, which is part of the Islands of Four Mountains just west of Umnak Island in the Fox Islands of the Aleutian Islands of Alaska.
Mt. Cleveland is 1,730 m high, and one of the most active of the 75 or more volcanoes in the larger Aleutian Arc. Aleutian natives named the island after their fire goddess, Chuginadak, who they believed inhabited the volcano.
In 1894 a team from the United States Coast and Geodetic Survey visited the island and gave Mount Cleveland its current name, after then-president Grover Cleveland.
One of the most active volcanoes in the Aleutian Arc, Cleveland has erupted at least 22 times in the last 230 years. A VEI 3 eruption in 1944 produced the arc's only known volcanic fatality. Most recently Mount Cleveland has erupted three times in 2009, twice in 2010, once in 2011 and in 2016 and 2017.
The volcano's remoteness limits opportunities for its study, and the Alaska Volcano Observatory relies heavily on satellites for monitoring. The volcano is primarily hazardous to aircraft; many of the flights over the north Pacific approach the vicinity of the volcano, and volcanic ash released from eruptions can damage sensitive electronic equipment and sensors.
Mount Cleveland is located 490 km from the western end of the Aleutian Arc, a long volcanic chain extending off the coast of Alaska.
Containing over 75 volcanoes, this volcanic arc occurs above the subduction zone where the Pacific Plate plunges under the North American plate. As the plate moves deeper into the earth, the increasing pressure results in the loss of volatiles, certain elements and compounds with low boiling points, from various hydrous minerals. One of these compounds is water; its addition to the mantle wedge formed between the subducting and overriding plates lowers the melting point enough to allow magma to form. The melted material then rises to the surface and forms a volcano -in this case, the Aleutian Arc.
The native Aleut name for Mount Cleveland is Chuginadak (the name currently given to the island as a whole), referring to the Aleut fire goddess, thought to reside in the volcano. The volcano's name is a reference to its constant activity, and shows that it was likely highly active even in the distant past.
Aleut oral tradition states that, at one time, the western and eastern halves of Chuginadak were separate islands, and that the isthmus joining them was created by volcanic activity sometime in prehistory.
The Islands of Four Mountains name, the geographic group name for Cleveland and its neighbours, was given to the islands by Russian cartographers in the 19th century. Its current name, Mount Cleveland, was given to it by a United States Coast and Geodetic Survey expedition in 1894, when it was originally observed by the USS Concord. Like the other volcanoes in the Four Islands group, which were named after prominent American politicians at the time, Mount Cleveland was named after then-president Grover Cleveland.
Mount Cleveland erupted more recently in 1951, 1953, 1954 (possibly), 1975 (possibly), 1984 through 1987, 1989, 1994, and 1997. The volcano has received more focused attention in recent times due to its increased activity: it erupted in 2001, 2005, three times in 2006, 2007, three times in 2009, and twice in 2010. Of these, the most significant eruption was the 2001 eruption, which produced a 12 km high ash plume. This plume dispersed 120 to 150 km across Alaska, an unusual distance that allowed detailed satellite observations to be made. Nikolski and the surrounding region was the site of several hours of ashfall, represented in satellite imagery as areas of discolored snow. This eruption significantly disrupted air traffic in the area.
More information: Alaska Volcano Observatory
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