VOLCANIC VORTEX RINGS -
GEOGRAPHY
News: A Sicilian volcano is blowing
smoke rings in the sky. What are volcanic vortex rings?
What's in the news?
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Since last week, Mount Etna, the largest volcano in
Europe, and among the world’s most active and iconic volcanoes, has been
sending up almost perfect rings of smoke into the air.
Key takeaways:
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The rings are a rare phenomenon that scientists refer to as volcanic vortex rings,
which are produced roughly in the same way as the smoke rings that some
cigarette smokers are able to blow out of their mouths.
Volcanic Vortex Rings:
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Vortex rings are generated when gas which is
predominantly water vapour, is released
rapidly through a vent in the crater.
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This phenomenon was first observed at Etna and
Vesuvius in Italy in 1724.
Features:
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They are made from a mix of smoke, steam and other gases released from volcanic vents at
high speeds.
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The rings can remain in the air for up to 10
minutes but tend to disintegrate quickly if conditions are windy and turbulent.
Recent Occurrences:
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Redoubt in Alaska
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Tungurahua in Ecuador
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Pacaya in Guatemala
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Eyjafjallajökull and Hekla in Iceland
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Stromboli in Italy
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Aso and Sakurajima in Japan
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Yasur in Vanuatu
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Whakaari in New Zealand
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Momotombo in Nicaragua
Vortex Rings at Mt.Etna:
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The vent that has opened up in Etna’s crater is
almost perfectly circular, so the
rings that have been seen above the mountain since recently are also circular.
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The rings are produced by the explosion of gas
bubbles within a narrow conduit, which shoots
the gas at high speed toward the surface.
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Attrition along the conduit walls slows the
movement of the gas jet, relative to the center of the conduit.
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They can linger in the air for up to 10 minutes but
may disintegrate quickly in windy conditions.
Does Producing Volcano
Rings mean Etna is about to Erupt Very Soon?
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Volcanologists do not believe so. As per them, this
event signifies that the activity from
the new vent was slowing down.
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They claim that this can stop because the
properties of the conduit that allowed for the formation of these volcanic
vortex rings can change, maybe with obstructions.